diff options
Diffstat (limited to 'kernel/trace')
50 files changed, 25357 insertions, 8403 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 1551f47e766..d4409356f40 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -11,44 +11,67 @@ config NOP_TRACER config HAVE_FTRACE_NMI_ENTER bool + help + See Documentation/trace/ftrace-design.txt config HAVE_FUNCTION_TRACER bool + help + See Documentation/trace/ftrace-design.txt config HAVE_FUNCTION_GRAPH_TRACER bool + help + See Documentation/trace/ftrace-design.txt config HAVE_FUNCTION_GRAPH_FP_TEST bool help - An arch may pass in a unique value (frame pointer) to both the - entering and exiting of a function. On exit, the value is compared - and if it does not match, then it will panic the kernel. + See Documentation/trace/ftrace-design.txt config HAVE_FUNCTION_TRACE_MCOUNT_TEST bool help - This gets selected when the arch tests the function_trace_stop - variable at the mcount call site. Otherwise, this variable - is tested by the called function. + See Documentation/trace/ftrace-design.txt config HAVE_DYNAMIC_FTRACE bool + help + See Documentation/trace/ftrace-design.txt + +config HAVE_DYNAMIC_FTRACE_WITH_REGS + bool config HAVE_FTRACE_MCOUNT_RECORD bool + help + See Documentation/trace/ftrace-design.txt -config HAVE_HW_BRANCH_TRACER +config HAVE_SYSCALL_TRACEPOINTS bool + help + See Documentation/trace/ftrace-design.txt -config HAVE_FTRACE_SYSCALLS +config HAVE_FENTRY bool + help + Arch supports the gcc options -pg with -mfentry + +config HAVE_C_RECORDMCOUNT + bool + help + C version of recordmcount available? config TRACER_MAX_TRACE bool +config TRACE_CLOCK + bool + config RING_BUFFER bool + select TRACE_CLOCK + select IRQ_WORK config FTRACE_NMI_ENTER bool @@ -60,15 +83,20 @@ config EVENT_TRACING bool config CONTEXT_SWITCH_TRACER - select MARKERS bool +config RING_BUFFER_ALLOW_SWAP + bool + help + Allow the use of ring_buffer_swap_cpu. + Adds a very slight overhead to tracing when enabled. + # All tracer options should select GENERIC_TRACER. For those options that are # enabled by all tracers (context switch and event tracer) they select TRACING. # This allows those options to appear when no other tracer is selected. But the # options do not appear when something else selects it. We need the two options # GENERIC_TRACER and TRACING to avoid circular dependencies to accomplish the -# hidding of the automatic options options. +# hiding of the automatic options. config TRACING bool @@ -79,6 +107,7 @@ config TRACING select NOP_TRACER select BINARY_PRINTF select EVENT_TRACING + select TRACE_CLOCK config GENERIC_TRACER bool @@ -104,21 +133,20 @@ menuconfig FTRACE bool "Tracers" default y if DEBUG_KERNEL help - Enable the kernel tracing infrastructure. + Enable the kernel tracing infrastructure. if FTRACE config FUNCTION_TRACER bool "Kernel Function Tracer" depends on HAVE_FUNCTION_TRACER - select FRAME_POINTER select KALLSYMS select GENERIC_TRACER select CONTEXT_SWITCH_TRACER help Enable the kernel to trace every kernel function. This is done by using a compiler feature to insert a small, 5-byte No-Operation - instruction to the beginning of every kernel function, which NOP + instruction at the beginning of every kernel function, which NOP sequence is then dynamically patched into a tracer call when tracing is enabled by the administrator. If it's runtime disabled (the bootup default), then the overhead of the instructions is very @@ -135,7 +163,7 @@ config FUNCTION_GRAPH_TRACER and its entry. Its first purpose is to trace the duration of functions and draw a call graph for each thread with some information like - the return value. This is done by setting the current return + the return value. This is done by setting the current return address on the current task structure into a stack of calls. @@ -143,10 +171,13 @@ config IRQSOFF_TRACER bool "Interrupts-off Latency Tracer" default n depends on TRACE_IRQFLAGS_SUPPORT - depends on GENERIC_TIME + depends on !ARCH_USES_GETTIMEOFFSET select TRACE_IRQFLAGS select GENERIC_TRACER select TRACER_MAX_TRACE + select RING_BUFFER_ALLOW_SWAP + select TRACER_SNAPSHOT + select TRACER_SNAPSHOT_PER_CPU_SWAP help This option measures the time spent in irqs-off critical sections, with microsecond accuracy. @@ -157,19 +188,22 @@ config IRQSOFF_TRACER echo 0 > /sys/kernel/debug/tracing/tracing_max_latency - (Note that kernel size and overhead increases with this option + (Note that kernel size and overhead increase with this option enabled. This option and the preempt-off timing option can be used together or separately.) config PREEMPT_TRACER bool "Preemption-off Latency Tracer" default n - depends on GENERIC_TIME + depends on !ARCH_USES_GETTIMEOFFSET depends on PREEMPT select GENERIC_TRACER select TRACER_MAX_TRACE + select RING_BUFFER_ALLOW_SWAP + select TRACER_SNAPSHOT + select TRACER_SNAPSHOT_PER_CPU_SWAP help - This option measures the time spent in preemption off critical + This option measures the time spent in preemption-off critical sections, with microsecond accuracy. The default measurement method is a maximum search, which is @@ -178,24 +212,16 @@ config PREEMPT_TRACER echo 0 > /sys/kernel/debug/tracing/tracing_max_latency - (Note that kernel size and overhead increases with this option + (Note that kernel size and overhead increase with this option enabled. This option and the irqs-off timing option can be used together or separately.) -config SYSPROF_TRACER - bool "Sysprof Tracer" - depends on X86 - select GENERIC_TRACER - select CONTEXT_SWITCH_TRACER - help - This tracer provides the trace needed by the 'Sysprof' userspace - tool. - config SCHED_TRACER bool "Scheduling Latency Tracer" select GENERIC_TRACER select CONTEXT_SWITCH_TRACER select TRACER_MAX_TRACE + select TRACER_SNAPSHOT help This tracer tracks the latency of the highest priority task to be scheduled in, starting from the point it has woken up. @@ -205,34 +231,48 @@ config ENABLE_DEFAULT_TRACERS depends on !GENERIC_TRACER select TRACING help - This tracer hooks to various trace points in the kernel + This tracer hooks to various trace points in the kernel, allowing the user to pick and choose which trace point they want to trace. It also includes the sched_switch tracer plugin. config FTRACE_SYSCALLS bool "Trace syscalls" - depends on HAVE_FTRACE_SYSCALLS + depends on HAVE_SYSCALL_TRACEPOINTS select GENERIC_TRACER select KALLSYMS help Basic tracer to catch the syscall entry and exit events. -config BOOT_TRACER - bool "Trace boot initcalls" - select GENERIC_TRACER - select CONTEXT_SWITCH_TRACER +config TRACER_SNAPSHOT + bool "Create a snapshot trace buffer" + select TRACER_MAX_TRACE + help + Allow tracing users to take snapshot of the current buffer using the + ftrace interface, e.g.: + + echo 1 > /sys/kernel/debug/tracing/snapshot + cat snapshot + +config TRACER_SNAPSHOT_PER_CPU_SWAP + bool "Allow snapshot to swap per CPU" + depends on TRACER_SNAPSHOT + select RING_BUFFER_ALLOW_SWAP help - This tracer helps developers to optimize boot times: it records - the timings of the initcalls and traces key events and the identity - of tasks that can cause boot delays, such as context-switches. + Allow doing a snapshot of a single CPU buffer instead of a + full swap (all buffers). If this is set, then the following is + allowed: - Its aim is to be parsed by the /scripts/bootgraph.pl tool to - produce pretty graphics about boot inefficiencies, giving a visual - representation of the delays during initcalls - but the raw - /debug/tracing/trace text output is readable too. + echo 1 > /sys/kernel/debug/tracing/per_cpu/cpu2/snapshot - You must pass in ftrace=initcall to the kernel command line - to enable this on bootup. + After which, only the tracing buffer for CPU 2 was swapped with + the main tracing buffer, and the other CPU buffers remain the same. + + When this is enabled, this adds a little more overhead to the + trace recording, as it needs to add some checks to synchronize + recording with swaps. But this does not affect the performance + of the overall system. This is enabled by default when the preempt + or irq latency tracers are enabled, as those need to swap as well + and already adds the overhead (plus a lot more). config TRACE_BRANCH_PROFILING bool @@ -248,30 +288,30 @@ choice The likely/unlikely profiler only looks at the conditions that are annotated with a likely or unlikely macro. - The "all branch" profiler will profile every if statement in the + The "all branch" profiler will profile every if-statement in the kernel. This profiler will also enable the likely/unlikely - profiler as well. + profiler. - Either of the above profilers add a bit of overhead to the system. - If unsure choose "No branch profiling". + Either of the above profilers adds a bit of overhead to the system. + If unsure, choose "No branch profiling". config BRANCH_PROFILE_NONE bool "No branch profiling" help - No branch profiling. Branch profiling adds a bit of overhead. - Only enable it if you want to analyse the branching behavior. - Otherwise keep it disabled. + No branch profiling. Branch profiling adds a bit of overhead. + Only enable it if you want to analyse the branching behavior. + Otherwise keep it disabled. config PROFILE_ANNOTATED_BRANCHES bool "Trace likely/unlikely profiler" select TRACE_BRANCH_PROFILING help - This tracer profiles all the the likely and unlikely macros + This tracer profiles all likely and unlikely macros in the kernel. It will display the results in: - /sys/kernel/debug/tracing/profile_annotated_branch + /sys/kernel/debug/tracing/trace_stat/branch_annotated - Note: this will add a significant overhead, only turn this + Note: this will add a significant overhead; only turn this on if you need to profile the system's use of these macros. config PROFILE_ALL_BRANCHES @@ -282,13 +322,13 @@ config PROFILE_ALL_BRANCHES taken in the kernel is recorded whether it hit or miss. The results will be displayed in: - /sys/kernel/debug/tracing/profile_branch + /sys/kernel/debug/tracing/trace_stat/branch_all This option also enables the likely/unlikely profiler. This configuration, when enabled, will impose a great overhead on the system. This should only be enabled when the system - is to be analyzed + is to be analyzed in much detail. endchoice config TRACING_BRANCHES @@ -313,16 +353,6 @@ config BRANCH_TRACER Say N if unsure. -config POWER_TRACER - bool "Trace power consumption behavior" - depends on X86 - select GENERIC_TRACER - help - This tracer helps developers to analyze and optimize the kernels - power management decisions, specifically the C-state and P-state - behavior. - - config STACK_TRACER bool "Trace max stack" depends on HAVE_FUNCTION_TRACER @@ -347,47 +377,8 @@ config STACK_TRACER Say N if unsure. -config HW_BRANCH_TRACER - depends on HAVE_HW_BRANCH_TRACER - bool "Trace hw branches" - select GENERIC_TRACER - help - This tracer records all branches on the system in a circular - buffer giving access to the last N branches for each cpu. - -config KMEMTRACE - bool "Trace SLAB allocations" - select GENERIC_TRACER - help - kmemtrace provides tracing for slab allocator functions, such as - kmalloc, kfree, kmem_cache_alloc, kmem_cache_free etc.. Collected - data is then fed to the userspace application in order to analyse - allocation hotspots, internal fragmentation and so on, making it - possible to see how well an allocator performs, as well as debug - and profile kernel code. - - This requires an userspace application to use. See - Documentation/trace/kmemtrace.txt for more information. - - Saying Y will make the kernel somewhat larger and slower. However, - if you disable kmemtrace at run-time or boot-time, the performance - impact is minimal (depending on the arch the kernel is built for). - - If unsure, say N. - -config WORKQUEUE_TRACER - bool "Trace workqueues" - select GENERIC_TRACER - help - The workqueue tracer provides some statistical informations - about each cpu workqueue thread such as the number of the - works inserted and executed since their creation. It can help - to evaluate the amount of work each of them have to perform. - For example it can help a developer to decide whether he should - choose a per cpu workqueue instead of a singlethreaded one. - config BLK_DEV_IO_TRACE - bool "Support for tracing block io actions" + bool "Support for tracing block IO actions" depends on SYSFS depends on BLOCK select RELAY @@ -411,38 +402,85 @@ config BLK_DEV_IO_TRACE If unsure, say N. +config KPROBE_EVENT + depends on KPROBES + depends on HAVE_REGS_AND_STACK_ACCESS_API + bool "Enable kprobes-based dynamic events" + select TRACING + select PROBE_EVENTS + default y + help + This allows the user to add tracing events (similar to tracepoints) + on the fly via the ftrace interface. See + Documentation/trace/kprobetrace.txt for more details. + + Those events can be inserted wherever kprobes can probe, and record + various register and memory values. + + This option is also required by perf-probe subcommand of perf tools. + If you want to use perf tools, this option is strongly recommended. + +config UPROBE_EVENT + bool "Enable uprobes-based dynamic events" + depends on ARCH_SUPPORTS_UPROBES + depends on MMU + depends on PERF_EVENTS + select UPROBES + select PROBE_EVENTS + select TRACING + default n + help + This allows the user to add tracing events on top of userspace + dynamic events (similar to tracepoints) on the fly via the trace + events interface. Those events can be inserted wherever uprobes + can probe, and record various registers. + This option is required if you plan to use perf-probe subcommand + of perf tools on user space applications. + +config PROBE_EVENTS + def_bool n + config DYNAMIC_FTRACE - bool "enable/disable ftrace tracepoints dynamically" + bool "enable/disable function tracing dynamically" depends on FUNCTION_TRACER depends on HAVE_DYNAMIC_FTRACE default y help - This option will modify all the calls to ftrace dynamically - (will patch them out of the binary image and replaces them - with a No-Op instruction) as they are called. A table is - created to dynamically enable them again. - - This way a CONFIG_FUNCTION_TRACER kernel is slightly larger, but otherwise - has native performance as long as no tracing is active. - - The changes to the code are done by a kernel thread that - wakes up once a second and checks to see if any ftrace calls - were made. If so, it runs stop_machine (stops all CPUS) - and modifies the code to jump over the call to ftrace. + This option will modify all the calls to function tracing + dynamically (will patch them out of the binary image and + replace them with a No-Op instruction) on boot up. During + compile time, a table is made of all the locations that ftrace + can function trace, and this table is linked into the kernel + image. When this is enabled, functions can be individually + enabled, and the functions not enabled will not affect + performance of the system. + + See the files in /sys/kernel/debug/tracing: + available_filter_functions + set_ftrace_filter + set_ftrace_notrace + + This way a CONFIG_FUNCTION_TRACER kernel is slightly larger, but + otherwise has native performance as long as no tracing is active. + +config DYNAMIC_FTRACE_WITH_REGS + def_bool y + depends on DYNAMIC_FTRACE + depends on HAVE_DYNAMIC_FTRACE_WITH_REGS config FUNCTION_PROFILER bool "Kernel function profiler" depends on FUNCTION_TRACER default n help - This option enables the kernel function profiler. A file is created - in debugfs called function_profile_enabled which defaults to zero. - When a 1 is echoed into this file profiling begins, and when a - zero is entered, profiling stops. A file in the trace_stats - directory called functions, that show the list of functions that - have been hit and their counters. + This option enables the kernel function profiler. A file is created + in debugfs called function_profile_enabled which defaults to zero. + When a 1 is echoed into this file profiling begins, and when a + zero is entered, profiling stops. A "functions" file is created in + the trace_stats directory; this file shows the list of functions that + have been hit and their counters. - If in doubt, say N + If in doubt, say N. config FTRACE_MCOUNT_RECORD def_bool y @@ -462,6 +500,18 @@ config FTRACE_STARTUP_TEST functioning properly. It will do tests on all the configured tracers of ftrace. +config EVENT_TRACE_TEST_SYSCALLS + bool "Run selftest on syscall events" + depends on FTRACE_STARTUP_TEST + help + This option will also enable testing every syscall event. + It only enables the event and disables it and runs various loads + with the event enabled. This adds a bit more time for kernel boot + up since it runs this on every system call defined. + + TBD - enable a way to actually call the syscalls as we test their + events + config MMIOTRACE bool "Memory mapped IO tracing" depends on HAVE_MMIOTRACE_SUPPORT && PCI @@ -485,12 +535,42 @@ config MMIOTRACE_TEST Say N, unless you absolutely know what you are doing. +config TRACEPOINT_BENCHMARK + bool "Add tracepoint that benchmarks tracepoints" + help + This option creates the tracepoint "benchmark:benchmark_event". + When the tracepoint is enabled, it kicks off a kernel thread that + goes into an infinite loop (calling cond_sched() to let other tasks + run), and calls the tracepoint. Each iteration will record the time + it took to write to the tracepoint and the next iteration that + data will be passed to the tracepoint itself. That is, the tracepoint + will report the time it took to do the previous tracepoint. + The string written to the tracepoint is a static string of 128 bytes + to keep the time the same. The initial string is simply a write of + "START". The second string records the cold cache time of the first + write which is not added to the rest of the calculations. + + As it is a tight loop, it benchmarks as hot cache. That's fine because + we care most about hot paths that are probably in cache already. + + An example of the output: + + START + first=3672 [COLD CACHED] + last=632 first=3672 max=632 min=632 avg=316 std=446 std^2=199712 + last=278 first=3672 max=632 min=278 avg=303 std=316 std^2=100337 + last=277 first=3672 max=632 min=277 avg=296 std=258 std^2=67064 + last=273 first=3672 max=632 min=273 avg=292 std=224 std^2=50411 + last=273 first=3672 max=632 min=273 avg=288 std=200 std^2=40389 + last=281 first=3672 max=632 min=273 avg=287 std=183 std^2=33666 + + config RING_BUFFER_BENCHMARK tristate "Ring buffer benchmark stress tester" depends on RING_BUFFER help - This option creates a test to stress the ring buffer and bench mark it. - It creates its own ring buffer such that it will not interfer with + This option creates a test to stress the ring buffer and benchmark it. + It creates its own ring buffer such that it will not interfere with any other users of the ring buffer (such as ftrace). It then creates a producer and consumer that will run for 10 seconds and sleep for 10 seconds. Each interval it will print out the number of events @@ -499,7 +579,30 @@ config RING_BUFFER_BENCHMARK It does not disable interrupts or raise its priority, so it may be affected by processes that are running. - If unsure, say N + If unsure, say N. + +config RING_BUFFER_STARTUP_TEST + bool "Ring buffer startup self test" + depends on RING_BUFFER + help + Run a simple self test on the ring buffer on boot up. Late in the + kernel boot sequence, the test will start that kicks off + a thread per cpu. Each thread will write various size events + into the ring buffer. Another thread is created to send IPIs + to each of the threads, where the IPI handler will also write + to the ring buffer, to test/stress the nesting ability. + If any anomalies are discovered, a warning will be displayed + and all ring buffers will be disabled. + + The test runs for 10 seconds. This will slow your boot time + by at least 10 more seconds. + + At the end of the test, statics and more checks are done. + It will output the stats of each per cpu buffer. What + was written, the sizes, what was read, what was lost, and + other similar details. + + If unsure, say N endif # FTRACE diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index 844164dca90..2611613f14f 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -5,21 +5,22 @@ ifdef CONFIG_FUNCTION_TRACER ORIG_CFLAGS := $(KBUILD_CFLAGS) KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS)) +ifdef CONFIG_FTRACE_SELFTEST # selftest needs instrumentation CFLAGS_trace_selftest_dynamic.o = -pg obj-y += trace_selftest_dynamic.o endif +endif # If unlikely tracing is enabled, do not trace these files ifdef CONFIG_TRACING_BRANCHES KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING endif -# -# Make the trace clocks available generally: it's infrastructure -# relied on by ptrace for example: -# -obj-y += trace_clock.o +CFLAGS_trace_benchmark.o := -I$(src) +CFLAGS_trace_events_filter.o := -I$(src) + +obj-$(CONFIG_TRACE_CLOCK) += trace_clock.o obj-$(CONFIG_FUNCTION_TRACER) += libftrace.o obj-$(CONFIG_RING_BUFFER) += ring_buffer.o @@ -30,7 +31,6 @@ obj-$(CONFIG_TRACING) += trace_output.o obj-$(CONFIG_TRACING) += trace_stat.o obj-$(CONFIG_TRACING) += trace_printk.o obj-$(CONFIG_CONTEXT_SWITCH_TRACER) += trace_sched_switch.o -obj-$(CONFIG_SYSPROF_TRACER) += trace_sysprof.o obj-$(CONFIG_FUNCTION_TRACER) += trace_functions.o obj-$(CONFIG_IRQSOFF_TRACER) += trace_irqsoff.o obj-$(CONFIG_PREEMPT_TRACER) += trace_irqsoff.o @@ -38,13 +38,8 @@ obj-$(CONFIG_SCHED_TRACER) += trace_sched_wakeup.o obj-$(CONFIG_NOP_TRACER) += trace_nop.o obj-$(CONFIG_STACK_TRACER) += trace_stack.o obj-$(CONFIG_MMIOTRACE) += trace_mmiotrace.o -obj-$(CONFIG_BOOT_TRACER) += trace_boot.o obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += trace_functions_graph.o obj-$(CONFIG_TRACE_BRANCH_PROFILING) += trace_branch.o -obj-$(CONFIG_HW_BRANCH_TRACER) += trace_hw_branches.o -obj-$(CONFIG_POWER_TRACER) += trace_power.o -obj-$(CONFIG_KMEMTRACE) += kmemtrace.o -obj-$(CONFIG_WORKQUEUE_TRACER) += trace_workqueue.o obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o ifeq ($(CONFIG_BLOCK),y) obj-$(CONFIG_EVENT_TRACING) += blktrace.o @@ -52,7 +47,22 @@ endif obj-$(CONFIG_EVENT_TRACING) += trace_events.o obj-$(CONFIG_EVENT_TRACING) += trace_export.o obj-$(CONFIG_FTRACE_SYSCALLS) += trace_syscalls.o -obj-$(CONFIG_EVENT_PROFILE) += trace_event_profile.o +ifeq ($(CONFIG_PERF_EVENTS),y) +obj-$(CONFIG_EVENT_TRACING) += trace_event_perf.o +endif obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o +obj-$(CONFIG_EVENT_TRACING) += trace_events_trigger.o +obj-$(CONFIG_KPROBE_EVENT) += trace_kprobe.o +obj-$(CONFIG_TRACEPOINTS) += power-traces.o +ifeq ($(CONFIG_PM_RUNTIME),y) +obj-$(CONFIG_TRACEPOINTS) += rpm-traces.o +endif +ifeq ($(CONFIG_TRACING),y) +obj-$(CONFIG_KGDB_KDB) += trace_kdb.o +endif +obj-$(CONFIG_PROBE_EVENTS) += trace_probe.o +obj-$(CONFIG_UPROBE_EVENT) += trace_uprobe.o + +obj-$(CONFIG_TRACEPOINT_BENCHMARK) += trace_benchmark.o libftrace-y := ftrace.o diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index 39af8af6fc3..c1bd4ada2a0 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -21,9 +21,12 @@ #include <linux/percpu.h> #include <linux/init.h> #include <linux/mutex.h> +#include <linux/slab.h> #include <linux/debugfs.h> +#include <linux/export.h> #include <linux/time.h> #include <linux/uaccess.h> +#include <linux/list.h> #include <trace/events/block.h> @@ -36,6 +39,9 @@ static unsigned int blktrace_seq __read_mostly = 1; static struct trace_array *blk_tr; static bool blk_tracer_enabled __read_mostly; +static LIST_HEAD(running_trace_list); +static __cacheline_aligned_in_smp DEFINE_SPINLOCK(running_trace_lock); + /* Select an alternative, minimalistic output than the original one */ #define TRACE_BLK_OPT_CLASSIC 0x1 @@ -64,13 +70,15 @@ static void trace_note(struct blk_trace *bt, pid_t pid, int action, { struct blk_io_trace *t; struct ring_buffer_event *event = NULL; + struct ring_buffer *buffer = NULL; int pc = 0; int cpu = smp_processor_id(); bool blk_tracer = blk_tracer_enabled; if (blk_tracer) { + buffer = blk_tr->trace_buffer.buffer; pc = preempt_count(); - event = trace_buffer_lock_reserve(blk_tr, TRACE_BLK, + event = trace_buffer_lock_reserve(buffer, TRACE_BLK, sizeof(*t) + len, 0, pc); if (!event) @@ -95,7 +103,7 @@ record_it: memcpy((void *) t + sizeof(*t), data, len); if (blk_tracer) - trace_buffer_unlock_commit(blk_tr, event, 0, pc); + trace_buffer_unlock_commit(buffer, event, 0, pc); } } @@ -103,10 +111,18 @@ record_it: * Send out a notify for this process, if we haven't done so since a trace * started */ -static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk) +static void trace_note_tsk(struct task_struct *tsk) { + unsigned long flags; + struct blk_trace *bt; + tsk->btrace_seq = blktrace_seq; - trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm, sizeof(tsk->comm)); + spin_lock_irqsave(&running_trace_lock, flags); + list_for_each_entry(bt, &running_trace_list, running_list) { + trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm, + sizeof(tsk->comm)); + } + spin_unlock_irqrestore(&running_trace_lock, flags); } static void trace_note_time(struct blk_trace *bt) @@ -135,8 +151,15 @@ void __trace_note_message(struct blk_trace *bt, const char *fmt, ...) !blk_tracer_enabled)) return; + /* + * If the BLK_TC_NOTIFY action mask isn't set, don't send any note + * message to the trace. + */ + if (!(bt->act_mask & BLK_TC_NOTIFY)) + return; + local_irq_save(flags); - buf = per_cpu_ptr(bt->msg_data, smp_processor_id()); + buf = this_cpu_ptr(bt->msg_data); va_start(args, fmt); n = vscnprintf(buf, BLK_TN_MAX_MSG, fmt, args); va_end(args); @@ -165,9 +188,11 @@ static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, static const u32 ddir_act[2] = { BLK_TC_ACT(BLK_TC_READ), BLK_TC_ACT(BLK_TC_WRITE) }; +#define BLK_TC_RAHEAD BLK_TC_AHEAD + /* The ilog2() calls fall out because they're constant */ -#define MASK_TC_BIT(rw, __name) ((rw & (1 << BIO_RW_ ## __name)) << \ - (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - BIO_RW_ ## __name)) +#define MASK_TC_BIT(rw, __name) ((rw & REQ_ ## __name) << \ + (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - __REQ_ ## __name)) /* * The worker for the various blk_add_trace*() types. Fills out a @@ -178,6 +203,7 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, { struct task_struct *tsk = current; struct ring_buffer_event *event = NULL; + struct ring_buffer *buffer = NULL; struct blk_io_trace *t; unsigned long flags = 0; unsigned long *sequence; @@ -189,11 +215,12 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, return; what |= ddir_act[rw & WRITE]; - what |= MASK_TC_BIT(rw, BARRIER); - what |= MASK_TC_BIT(rw, SYNCIO); - what |= MASK_TC_BIT(rw, AHEAD); + what |= MASK_TC_BIT(rw, SYNC); + what |= MASK_TC_BIT(rw, RAHEAD); what |= MASK_TC_BIT(rw, META); what |= MASK_TC_BIT(rw, DISCARD); + what |= MASK_TC_BIT(rw, FLUSH); + what |= MASK_TC_BIT(rw, FUA); pid = tsk->pid; if (act_log_check(bt, what, sector, pid)) @@ -203,8 +230,9 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, if (blk_tracer) { tracing_record_cmdline(current); + buffer = blk_tr->trace_buffer.buffer; pc = preempt_count(); - event = trace_buffer_lock_reserve(blk_tr, TRACE_BLK, + event = trace_buffer_lock_reserve(buffer, TRACE_BLK, sizeof(*t) + pdu_len, 0, pc); if (!event) @@ -213,16 +241,15 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, goto record_it; } + if (unlikely(tsk->btrace_seq != blktrace_seq)) + trace_note_tsk(tsk); + /* * A word about the locking here - we disable interrupts to reserve * some space in the relay per-cpu buffer, to prevent an irq * from coming in and stepping on our toes. */ local_irq_save(flags); - - if (unlikely(tsk->btrace_seq != blktrace_seq)) - trace_note_tsk(bt, tsk); - t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); if (t) { sequence = per_cpu_ptr(bt->sequence, cpu); @@ -251,7 +278,7 @@ record_it: memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); if (blk_tracer) { - trace_buffer_unlock_commit(blk_tr, event, 0, pc); + trace_buffer_unlock_commit(buffer, event, 0, pc); return; } } @@ -266,8 +293,8 @@ static void blk_trace_free(struct blk_trace *bt) { debugfs_remove(bt->msg_file); debugfs_remove(bt->dropped_file); - debugfs_remove(bt->dir); relay_close(bt->rchan); + debugfs_remove(bt->dir); free_percpu(bt->sequence); free_percpu(bt->msg_data); kfree(bt); @@ -295,13 +322,6 @@ int blk_trace_remove(struct request_queue *q) } EXPORT_SYMBOL_GPL(blk_trace_remove); -static int blk_dropped_open(struct inode *inode, struct file *filp) -{ - filp->private_data = inode->i_private; - - return 0; -} - static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, size_t count, loff_t *ppos) { @@ -315,17 +335,11 @@ static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, static const struct file_operations blk_dropped_fops = { .owner = THIS_MODULE, - .open = blk_dropped_open, + .open = simple_open, .read = blk_dropped_read, + .llseek = default_llseek, }; -static int blk_msg_open(struct inode *inode, struct file *filp) -{ - filp->private_data = inode->i_private; - - return 0; -} - static ssize_t blk_msg_write(struct file *filp, const char __user *buffer, size_t count, loff_t *ppos) { @@ -354,8 +368,9 @@ static ssize_t blk_msg_write(struct file *filp, const char __user *buffer, static const struct file_operations blk_msg_fops = { .owner = THIS_MODULE, - .open = blk_msg_open, + .open = simple_open, .write = blk_msg_write, + .llseek = noop_llseek, }; /* @@ -377,24 +392,14 @@ static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, static int blk_remove_buf_file_callback(struct dentry *dentry) { - struct dentry *parent = dentry->d_parent; debugfs_remove(dentry); - /* - * this will fail for all but the last file, but that is ok. what we - * care about is the top level buts->name directory going away, when - * the last trace file is gone. Then we don't have to rmdir() that - * manually on trace stop, so it nicely solves the issue with - * force killing of running traces. - */ - - debugfs_remove(parent); return 0; } static struct dentry *blk_create_buf_file_callback(const char *filename, struct dentry *parent, - int mode, + umode_t mode, struct rchan_buf *buf, int *is_global) { @@ -483,6 +488,7 @@ int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, bt->dir = dir; bt->dev = dev; atomic_set(&bt->dropped, 0); + INIT_LIST_HEAD(&bt->running_list); ret = -EIO; bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, @@ -545,13 +551,48 @@ int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, if (ret) return ret; - if (copy_to_user(arg, &buts, sizeof(buts))) + if (copy_to_user(arg, &buts, sizeof(buts))) { + blk_trace_remove(q); return -EFAULT; - + } return 0; } EXPORT_SYMBOL_GPL(blk_trace_setup); +#if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) +static int compat_blk_trace_setup(struct request_queue *q, char *name, + dev_t dev, struct block_device *bdev, + char __user *arg) +{ + struct blk_user_trace_setup buts; + struct compat_blk_user_trace_setup cbuts; + int ret; + + if (copy_from_user(&cbuts, arg, sizeof(cbuts))) + return -EFAULT; + + buts = (struct blk_user_trace_setup) { + .act_mask = cbuts.act_mask, + .buf_size = cbuts.buf_size, + .buf_nr = cbuts.buf_nr, + .start_lba = cbuts.start_lba, + .end_lba = cbuts.end_lba, + .pid = cbuts.pid, + }; + + ret = do_blk_trace_setup(q, name, dev, bdev, &buts); + if (ret) + return ret; + + if (copy_to_user(arg, &buts.name, ARRAY_SIZE(buts.name))) { + blk_trace_remove(q); + return -EFAULT; + } + + return 0; +} +#endif + int blk_trace_startstop(struct request_queue *q, int start) { int ret; @@ -571,6 +612,9 @@ int blk_trace_startstop(struct request_queue *q, int start) blktrace_seq++; smp_mb(); bt->trace_state = Blktrace_running; + spin_lock_irq(&running_trace_lock); + list_add(&bt->running_list, &running_trace_list); + spin_unlock_irq(&running_trace_lock); trace_note_time(bt); ret = 0; @@ -578,6 +622,9 @@ int blk_trace_startstop(struct request_queue *q, int start) } else { if (bt->trace_state == Blktrace_running) { bt->trace_state = Blktrace_stopped; + spin_lock_irq(&running_trace_lock); + list_del_init(&bt->running_list); + spin_unlock_irq(&running_trace_lock); relay_flush(bt->rchan); ret = 0; } @@ -611,6 +658,12 @@ int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) bdevname(bdev, b); ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); break; +#if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) + case BLKTRACESETUP32: + bdevname(bdev, b); + ret = compat_blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); + break; +#endif case BLKTRACESTART: start = 1; case BLKTRACESTOP: @@ -649,6 +702,7 @@ void blk_trace_shutdown(struct request_queue *q) * blk_add_trace_rq - Add a trace for a request oriented action * @q: queue the io is for * @rq: the source request + * @nr_bytes: number of completed bytes * @what: the action * * Description: @@ -656,53 +710,55 @@ void blk_trace_shutdown(struct request_queue *q) * **/ static void blk_add_trace_rq(struct request_queue *q, struct request *rq, - u32 what) + unsigned int nr_bytes, u32 what) { struct blk_trace *bt = q->blk_trace; - int rw = rq->cmd_flags & 0x03; if (likely(!bt)) return; - if (blk_discard_rq(rq)) - rw |= (1 << BIO_RW_DISCARD); - - if (blk_pc_request(rq)) { + if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { what |= BLK_TC_ACT(BLK_TC_PC); - __blk_add_trace(bt, 0, blk_rq_bytes(rq), rw, + __blk_add_trace(bt, 0, nr_bytes, rq->cmd_flags, what, rq->errors, rq->cmd_len, rq->cmd); } else { what |= BLK_TC_ACT(BLK_TC_FS); - __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), rw, - what, rq->errors, 0, NULL); + __blk_add_trace(bt, blk_rq_pos(rq), nr_bytes, + rq->cmd_flags, what, rq->errors, 0, NULL); } } -static void blk_add_trace_rq_abort(struct request_queue *q, struct request *rq) +static void blk_add_trace_rq_abort(void *ignore, + struct request_queue *q, struct request *rq) { - blk_add_trace_rq(q, rq, BLK_TA_ABORT); + blk_add_trace_rq(q, rq, blk_rq_bytes(rq), BLK_TA_ABORT); } -static void blk_add_trace_rq_insert(struct request_queue *q, struct request *rq) +static void blk_add_trace_rq_insert(void *ignore, + struct request_queue *q, struct request *rq) { - blk_add_trace_rq(q, rq, BLK_TA_INSERT); + blk_add_trace_rq(q, rq, blk_rq_bytes(rq), BLK_TA_INSERT); } -static void blk_add_trace_rq_issue(struct request_queue *q, struct request *rq) +static void blk_add_trace_rq_issue(void *ignore, + struct request_queue *q, struct request *rq) { - blk_add_trace_rq(q, rq, BLK_TA_ISSUE); + blk_add_trace_rq(q, rq, blk_rq_bytes(rq), BLK_TA_ISSUE); } -static void blk_add_trace_rq_requeue(struct request_queue *q, +static void blk_add_trace_rq_requeue(void *ignore, + struct request_queue *q, struct request *rq) { - blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); + blk_add_trace_rq(q, rq, blk_rq_bytes(rq), BLK_TA_REQUEUE); } -static void blk_add_trace_rq_complete(struct request_queue *q, - struct request *rq) +static void blk_add_trace_rq_complete(void *ignore, + struct request_queue *q, + struct request *rq, + unsigned int nr_bytes) { - blk_add_trace_rq(q, rq, BLK_TA_COMPLETE); + blk_add_trace_rq(q, rq, nr_bytes, BLK_TA_COMPLETE); } /** @@ -710,55 +766,68 @@ static void blk_add_trace_rq_complete(struct request_queue *q, * @q: queue the io is for * @bio: the source bio * @what: the action + * @error: error, if any * * Description: * Records an action against a bio. Will log the bio offset + size. * **/ static void blk_add_trace_bio(struct request_queue *q, struct bio *bio, - u32 what) + u32 what, int error) { struct blk_trace *bt = q->blk_trace; if (likely(!bt)) return; - __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, - !bio_flagged(bio, BIO_UPTODATE), 0, NULL); + if (!error && !bio_flagged(bio, BIO_UPTODATE)) + error = EIO; + + __blk_add_trace(bt, bio->bi_iter.bi_sector, bio->bi_iter.bi_size, + bio->bi_rw, what, error, 0, NULL); } -static void blk_add_trace_bio_bounce(struct request_queue *q, struct bio *bio) +static void blk_add_trace_bio_bounce(void *ignore, + struct request_queue *q, struct bio *bio) { - blk_add_trace_bio(q, bio, BLK_TA_BOUNCE); + blk_add_trace_bio(q, bio, BLK_TA_BOUNCE, 0); } -static void blk_add_trace_bio_complete(struct request_queue *q, struct bio *bio) +static void blk_add_trace_bio_complete(void *ignore, + struct request_queue *q, struct bio *bio, + int error) { - blk_add_trace_bio(q, bio, BLK_TA_COMPLETE); + blk_add_trace_bio(q, bio, BLK_TA_COMPLETE, error); } -static void blk_add_trace_bio_backmerge(struct request_queue *q, +static void blk_add_trace_bio_backmerge(void *ignore, + struct request_queue *q, + struct request *rq, struct bio *bio) { - blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); + blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE, 0); } -static void blk_add_trace_bio_frontmerge(struct request_queue *q, +static void blk_add_trace_bio_frontmerge(void *ignore, + struct request_queue *q, + struct request *rq, struct bio *bio) { - blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); + blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE, 0); } -static void blk_add_trace_bio_queue(struct request_queue *q, struct bio *bio) +static void blk_add_trace_bio_queue(void *ignore, + struct request_queue *q, struct bio *bio) { - blk_add_trace_bio(q, bio, BLK_TA_QUEUE); + blk_add_trace_bio(q, bio, BLK_TA_QUEUE, 0); } -static void blk_add_trace_getrq(struct request_queue *q, +static void blk_add_trace_getrq(void *ignore, + struct request_queue *q, struct bio *bio, int rw) { if (bio) - blk_add_trace_bio(q, bio, BLK_TA_GETRQ); + blk_add_trace_bio(q, bio, BLK_TA_GETRQ, 0); else { struct blk_trace *bt = q->blk_trace; @@ -768,11 +837,12 @@ static void blk_add_trace_getrq(struct request_queue *q, } -static void blk_add_trace_sleeprq(struct request_queue *q, +static void blk_add_trace_sleeprq(void *ignore, + struct request_queue *q, struct bio *bio, int rw) { if (bio) - blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ); + blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ, 0); else { struct blk_trace *bt = q->blk_trace; @@ -782,7 +852,7 @@ static void blk_add_trace_sleeprq(struct request_queue *q, } } -static void blk_add_trace_plug(struct request_queue *q) +static void blk_add_trace_plug(void *ignore, struct request_queue *q) { struct blk_trace *bt = q->blk_trace; @@ -790,33 +860,26 @@ static void blk_add_trace_plug(struct request_queue *q) __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); } -static void blk_add_trace_unplug_io(struct request_queue *q) +static void blk_add_trace_unplug(void *ignore, struct request_queue *q, + unsigned int depth, bool explicit) { struct blk_trace *bt = q->blk_trace; if (bt) { - unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; - __be64 rpdu = cpu_to_be64(pdu); - - __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_IO, 0, - sizeof(rpdu), &rpdu); - } -} - -static void blk_add_trace_unplug_timer(struct request_queue *q) -{ - struct blk_trace *bt = q->blk_trace; + __be64 rpdu = cpu_to_be64(depth); + u32 what; - if (bt) { - unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; - __be64 rpdu = cpu_to_be64(pdu); + if (explicit) + what = BLK_TA_UNPLUG_IO; + else + what = BLK_TA_UNPLUG_TIMER; - __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_TIMER, 0, - sizeof(rpdu), &rpdu); + __blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu); } } -static void blk_add_trace_split(struct request_queue *q, struct bio *bio, +static void blk_add_trace_split(void *ignore, + struct request_queue *q, struct bio *bio, unsigned int pdu) { struct blk_trace *bt = q->blk_trace; @@ -824,14 +887,16 @@ static void blk_add_trace_split(struct request_queue *q, struct bio *bio, if (bt) { __be64 rpdu = cpu_to_be64(pdu); - __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, - BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE), + __blk_add_trace(bt, bio->bi_iter.bi_sector, + bio->bi_iter.bi_size, bio->bi_rw, BLK_TA_SPLIT, + !bio_flagged(bio, BIO_UPTODATE), sizeof(rpdu), &rpdu); } } /** - * blk_add_trace_remap - Add a trace for a remap operation + * blk_add_trace_bio_remap - Add a trace for a bio-remap operation + * @ignore: trace callback data parameter (not used) * @q: queue the io is for * @bio: the source bio * @dev: target device @@ -842,8 +907,9 @@ static void blk_add_trace_split(struct request_queue *q, struct bio *bio, * it spans a stripe (or similar). Add a trace for that action. * **/ -static void blk_add_trace_remap(struct request_queue *q, struct bio *bio, - dev_t dev, sector_t from) +static void blk_add_trace_bio_remap(void *ignore, + struct request_queue *q, struct bio *bio, + dev_t dev, sector_t from) { struct blk_trace *bt = q->blk_trace; struct blk_io_trace_remap r; @@ -855,8 +921,41 @@ static void blk_add_trace_remap(struct request_queue *q, struct bio *bio, r.device_to = cpu_to_be32(bio->bi_bdev->bd_dev); r.sector_from = cpu_to_be64(from); - __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, - BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), + __blk_add_trace(bt, bio->bi_iter.bi_sector, bio->bi_iter.bi_size, + bio->bi_rw, BLK_TA_REMAP, + !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r); +} + +/** + * blk_add_trace_rq_remap - Add a trace for a request-remap operation + * @ignore: trace callback data parameter (not used) + * @q: queue the io is for + * @rq: the source request + * @dev: target device + * @from: source sector + * + * Description: + * Device mapper remaps request to other devices. + * Add a trace for that action. + * + **/ +static void blk_add_trace_rq_remap(void *ignore, + struct request_queue *q, + struct request *rq, dev_t dev, + sector_t from) +{ + struct blk_trace *bt = q->blk_trace; + struct blk_io_trace_remap r; + + if (likely(!bt)) + return; + + r.device_from = cpu_to_be32(dev); + r.device_to = cpu_to_be32(disk_devt(rq->rq_disk)); + r.sector_from = cpu_to_be64(from); + + __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), + rq_data_dir(rq), BLK_TA_REMAP, !!rq->errors, sizeof(r), &r); } @@ -880,7 +979,7 @@ void blk_add_driver_data(struct request_queue *q, if (likely(!bt)) return; - if (blk_pc_request(rq)) + if (rq->cmd_type == REQ_TYPE_BLOCK_PC) __blk_add_trace(bt, 0, blk_rq_bytes(rq), 0, BLK_TA_DRV_DATA, rq->errors, len, data); else @@ -893,61 +992,61 @@ static void blk_register_tracepoints(void) { int ret; - ret = register_trace_block_rq_abort(blk_add_trace_rq_abort); + ret = register_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); WARN_ON(ret); - ret = register_trace_block_rq_insert(blk_add_trace_rq_insert); + ret = register_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); WARN_ON(ret); - ret = register_trace_block_rq_issue(blk_add_trace_rq_issue); + ret = register_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); WARN_ON(ret); - ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue); + ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); WARN_ON(ret); - ret = register_trace_block_rq_complete(blk_add_trace_rq_complete); + ret = register_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); WARN_ON(ret); - ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce); + ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); WARN_ON(ret); - ret = register_trace_block_bio_complete(blk_add_trace_bio_complete); + ret = register_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); WARN_ON(ret); - ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge); + ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); WARN_ON(ret); - ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge); + ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); WARN_ON(ret); - ret = register_trace_block_bio_queue(blk_add_trace_bio_queue); + ret = register_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); WARN_ON(ret); - ret = register_trace_block_getrq(blk_add_trace_getrq); + ret = register_trace_block_getrq(blk_add_trace_getrq, NULL); WARN_ON(ret); - ret = register_trace_block_sleeprq(blk_add_trace_sleeprq); + ret = register_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); WARN_ON(ret); - ret = register_trace_block_plug(blk_add_trace_plug); + ret = register_trace_block_plug(blk_add_trace_plug, NULL); WARN_ON(ret); - ret = register_trace_block_unplug_timer(blk_add_trace_unplug_timer); + ret = register_trace_block_unplug(blk_add_trace_unplug, NULL); WARN_ON(ret); - ret = register_trace_block_unplug_io(blk_add_trace_unplug_io); + ret = register_trace_block_split(blk_add_trace_split, NULL); WARN_ON(ret); - ret = register_trace_block_split(blk_add_trace_split); + ret = register_trace_block_bio_remap(blk_add_trace_bio_remap, NULL); WARN_ON(ret); - ret = register_trace_block_remap(blk_add_trace_remap); + ret = register_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); WARN_ON(ret); } static void blk_unregister_tracepoints(void) { - unregister_trace_block_remap(blk_add_trace_remap); - unregister_trace_block_split(blk_add_trace_split); - unregister_trace_block_unplug_io(blk_add_trace_unplug_io); - unregister_trace_block_unplug_timer(blk_add_trace_unplug_timer); - unregister_trace_block_plug(blk_add_trace_plug); - unregister_trace_block_sleeprq(blk_add_trace_sleeprq); - unregister_trace_block_getrq(blk_add_trace_getrq); - unregister_trace_block_bio_queue(blk_add_trace_bio_queue); - unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge); - unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge); - unregister_trace_block_bio_complete(blk_add_trace_bio_complete); - unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce); - unregister_trace_block_rq_complete(blk_add_trace_rq_complete); - unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue); - unregister_trace_block_rq_issue(blk_add_trace_rq_issue); - unregister_trace_block_rq_insert(blk_add_trace_rq_insert); - unregister_trace_block_rq_abort(blk_add_trace_rq_abort); + unregister_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); + unregister_trace_block_bio_remap(blk_add_trace_bio_remap, NULL); + unregister_trace_block_split(blk_add_trace_split, NULL); + unregister_trace_block_unplug(blk_add_trace_unplug, NULL); + unregister_trace_block_plug(blk_add_trace_plug, NULL); + unregister_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); + unregister_trace_block_getrq(blk_add_trace_getrq, NULL); + unregister_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); + unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); + unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); + unregister_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); + unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); + unregister_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); + unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); + unregister_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); + unregister_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); + unregister_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); tracepoint_synchronize_unregister(); } @@ -966,6 +1065,9 @@ static void fill_rwbs(char *rwbs, const struct blk_io_trace *t) goto out; } + if (tc & BLK_TC_FLUSH) + rwbs[i++] = 'F'; + if (tc & BLK_TC_DISCARD) rwbs[i++] = 'D'; else if (tc & BLK_TC_WRITE) @@ -975,10 +1077,10 @@ static void fill_rwbs(char *rwbs, const struct blk_io_trace *t) else rwbs[i++] = 'N'; + if (tc & BLK_TC_FUA) + rwbs[i++] = 'F'; if (tc & BLK_TC_AHEAD) rwbs[i++] = 'A'; - if (tc & BLK_TC_BARRIER) - rwbs[i++] = 'B'; if (tc & BLK_TC_SYNC) rwbs[i++] = 'S'; if (tc & BLK_TC_META) @@ -1044,7 +1146,7 @@ typedef int (blk_log_action_t) (struct trace_iterator *iter, const char *act); static int blk_log_action_classic(struct trace_iterator *iter, const char *act) { - char rwbs[6]; + char rwbs[RWBS_LEN]; unsigned long long ts = iter->ts; unsigned long nsec_rem = do_div(ts, NSEC_PER_SEC); unsigned secs = (unsigned long)ts; @@ -1060,7 +1162,7 @@ static int blk_log_action_classic(struct trace_iterator *iter, const char *act) static int blk_log_action(struct trace_iterator *iter, const char *act) { - char rwbs[6]; + char rwbs[RWBS_LEN]; const struct blk_io_trace *t = te_blk_io_trace(iter->ent); fill_rwbs(rwbs, t); @@ -1290,7 +1392,7 @@ out: } static enum print_line_t blk_trace_event_print(struct trace_iterator *iter, - int flags) + int flags, struct trace_event *event) { return print_one_line(iter, false); } @@ -1312,7 +1414,8 @@ static int blk_trace_synthesize_old_trace(struct trace_iterator *iter) } static enum print_line_t -blk_trace_event_print_binary(struct trace_iterator *iter, int flags) +blk_trace_event_print_binary(struct trace_iterator *iter, int flags, + struct trace_event *event) { return blk_trace_synthesize_old_trace(iter) ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; @@ -1326,7 +1429,8 @@ static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter) return print_one_line(iter, true); } -static int blk_tracer_set_flag(u32 old_flags, u32 bit, int set) +static int +blk_tracer_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) { /* don't output context-info for blk_classic output */ if (bit == TRACE_BLK_OPT_CLASSIC) { @@ -1350,12 +1454,16 @@ static struct tracer blk_tracer __read_mostly = { .set_flag = blk_tracer_set_flag, }; -static struct trace_event trace_blk_event = { - .type = TRACE_BLK, +static struct trace_event_functions trace_blk_event_funcs = { .trace = blk_trace_event_print, .binary = blk_trace_event_print_binary, }; +static struct trace_event trace_blk_event = { + .type = TRACE_BLK, + .funcs = &trace_blk_event_funcs, +}; + static int __init init_blk_tracer(void) { if (!register_ftrace_event(&trace_blk_event)) { @@ -1385,6 +1493,9 @@ static int blk_trace_remove_queue(struct request_queue *q) if (atomic_dec_and_test(&blk_probes_ref)) blk_unregister_tracepoints(); + spin_lock_irq(&running_trace_lock); + list_del(&bt->running_list); + spin_unlock_irq(&running_trace_lock); blk_trace_free(bt); return 0; } @@ -1468,7 +1579,7 @@ static const struct { } mask_maps[] = { { BLK_TC_READ, "read" }, { BLK_TC_WRITE, "write" }, - { BLK_TC_BARRIER, "barrier" }, + { BLK_TC_FLUSH, "flush" }, { BLK_TC_SYNC, "sync" }, { BLK_TC_QUEUE, "queue" }, { BLK_TC_REQUEUE, "requeue" }, @@ -1480,6 +1591,7 @@ static const struct { { BLK_TC_META, "meta" }, { BLK_TC_DISCARD, "discard" }, { BLK_TC_DRV_DATA, "drv_data" }, + { BLK_TC_FUA, "fua" }, }; static int blk_trace_str2mask(const char *str) @@ -1550,10 +1662,9 @@ static ssize_t sysfs_blk_trace_attr_show(struct device *dev, struct block_device *bdev; ssize_t ret = -ENXIO; - lock_kernel(); bdev = bdget(part_devt(p)); if (bdev == NULL) - goto out_unlock_kernel; + goto out; q = blk_trace_get_queue(bdev); if (q == NULL) @@ -1581,8 +1692,7 @@ out_unlock_bdev: mutex_unlock(&bdev->bd_mutex); out_bdput: bdput(bdev); -out_unlock_kernel: - unlock_kernel(); +out: return ret; } @@ -1612,11 +1722,10 @@ static ssize_t sysfs_blk_trace_attr_store(struct device *dev, ret = -ENXIO; - lock_kernel(); p = dev_to_part(dev); bdev = bdget(part_devt(p)); if (bdev == NULL) - goto out_unlock_kernel; + goto out; q = blk_trace_get_queue(bdev); if (q == NULL) @@ -1651,8 +1760,6 @@ out_unlock_bdev: mutex_unlock(&bdev->bd_mutex); out_bdput: bdput(bdev); -out_unlock_kernel: - unlock_kernel(); out: return ret ? ret : count; } @@ -1662,6 +1769,11 @@ int blk_trace_init_sysfs(struct device *dev) return sysfs_create_group(&dev->kobj, &blk_trace_attr_group); } +void blk_trace_remove_sysfs(struct device *dev) +{ + sysfs_remove_group(&dev->kobj, &blk_trace_attr_group); +} + #endif /* CONFIG_BLK_DEV_IO_TRACE */ #ifdef CONFIG_EVENT_TRACING @@ -1672,7 +1784,7 @@ void blk_dump_cmd(char *buf, struct request *rq) int len = rq->cmd_len; unsigned char *cmd = rq->cmd; - if (!blk_pc_request(rq)) { + if (rq->cmd_type != REQ_TYPE_BLOCK_PC) { buf[0] = '\0'; return; } @@ -1695,39 +1807,32 @@ void blk_fill_rwbs(char *rwbs, u32 rw, int bytes) { int i = 0; + if (rw & REQ_FLUSH) + rwbs[i++] = 'F'; + if (rw & WRITE) rwbs[i++] = 'W'; - else if (rw & 1 << BIO_RW_DISCARD) + else if (rw & REQ_DISCARD) rwbs[i++] = 'D'; else if (bytes) rwbs[i++] = 'R'; else rwbs[i++] = 'N'; - if (rw & 1 << BIO_RW_AHEAD) + if (rw & REQ_FUA) + rwbs[i++] = 'F'; + if (rw & REQ_RAHEAD) rwbs[i++] = 'A'; - if (rw & 1 << BIO_RW_BARRIER) - rwbs[i++] = 'B'; - if (rw & 1 << BIO_RW_SYNCIO) + if (rw & REQ_SYNC) rwbs[i++] = 'S'; - if (rw & 1 << BIO_RW_META) + if (rw & REQ_META) rwbs[i++] = 'M'; + if (rw & REQ_SECURE) + rwbs[i++] = 'E'; rwbs[i] = '\0'; } - -void blk_fill_rwbs_rq(char *rwbs, struct request *rq) -{ - int rw = rq->cmd_flags & 0x03; - int bytes; - - if (blk_discard_rq(rq)) - rw |= (1 << BIO_RW_DISCARD); - - bytes = blk_rq_bytes(rq); - - blk_fill_rwbs(rwbs, rw, bytes); -} +EXPORT_SYMBOL_GPL(blk_fill_rwbs); #endif /* CONFIG_EVENT_TRACING */ diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index f3716bf04df..ac9d1dad630 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -10,7 +10,7 @@ * Based on code in the latency_tracer, that is: * * Copyright (C) 2004-2006 Ingo Molnar - * Copyright (C) 2004 William Lee Irwin III + * Copyright (C) 2004 Nadia Yvette Chambers */ #include <linux/stop_machine.h> @@ -22,43 +22,78 @@ #include <linux/hardirq.h> #include <linux/kthread.h> #include <linux/uaccess.h> -#include <linux/kprobes.h> +#include <linux/bsearch.h> +#include <linux/module.h> #include <linux/ftrace.h> #include <linux/sysctl.h> +#include <linux/slab.h> #include <linux/ctype.h> +#include <linux/sort.h> #include <linux/list.h> #include <linux/hash.h> +#include <linux/rcupdate.h> #include <trace/events/sched.h> -#include <asm/ftrace.h> #include <asm/setup.h> #include "trace_output.h" #include "trace_stat.h" #define FTRACE_WARN_ON(cond) \ - do { \ - if (WARN_ON(cond)) \ + ({ \ + int ___r = cond; \ + if (WARN_ON(___r)) \ ftrace_kill(); \ - } while (0) + ___r; \ + }) #define FTRACE_WARN_ON_ONCE(cond) \ - do { \ - if (WARN_ON_ONCE(cond)) \ + ({ \ + int ___r = cond; \ + if (WARN_ON_ONCE(___r)) \ ftrace_kill(); \ - } while (0) + ___r; \ + }) /* hash bits for specific function selection */ #define FTRACE_HASH_BITS 7 #define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS) +#define FTRACE_HASH_DEFAULT_BITS 10 +#define FTRACE_HASH_MAX_BITS 12 + +#define FL_GLOBAL_CONTROL_MASK (FTRACE_OPS_FL_CONTROL) + +#ifdef CONFIG_DYNAMIC_FTRACE +#define INIT_REGEX_LOCK(opsname) \ + .regex_lock = __MUTEX_INITIALIZER(opsname.regex_lock), +#else +#define INIT_REGEX_LOCK(opsname) +#endif + +static struct ftrace_ops ftrace_list_end __read_mostly = { + .func = ftrace_stub, + .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_STUB, +}; /* ftrace_enabled is a method to turn ftrace on or off */ int ftrace_enabled __read_mostly; static int last_ftrace_enabled; /* Quick disabling of function tracer. */ -int function_trace_stop; +int function_trace_stop __read_mostly; + +/* Current function tracing op */ +struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end; +/* What to set function_trace_op to */ +static struct ftrace_ops *set_function_trace_op; + +/* List for set_ftrace_pid's pids. */ +LIST_HEAD(ftrace_pids); +struct ftrace_pid { + struct list_head list; + struct pid *pid; +}; /* * ftrace_disabled is set when an anomaly is discovered. @@ -68,37 +103,80 @@ static int ftrace_disabled __read_mostly; static DEFINE_MUTEX(ftrace_lock); -static struct ftrace_ops ftrace_list_end __read_mostly = -{ - .func = ftrace_stub, -}; - -static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end; +static struct ftrace_ops *ftrace_control_list __read_mostly = &ftrace_list_end; +static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end; ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; -ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub; ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub; +static struct ftrace_ops global_ops; +static struct ftrace_ops control_ops; + +#if ARCH_SUPPORTS_FTRACE_OPS +static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct pt_regs *regs); +#else +/* See comment below, where ftrace_ops_list_func is defined */ +static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip); +#define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops) +#endif + +/* + * Traverse the ftrace_global_list, invoking all entries. The reason that we + * can use rcu_dereference_raw_notrace() is that elements removed from this list + * are simply leaked, so there is no need to interact with a grace-period + * mechanism. The rcu_dereference_raw_notrace() calls are needed to handle + * concurrent insertions into the ftrace_global_list. + * + * Silly Alpha and silly pointer-speculation compiler optimizations! + */ +#define do_for_each_ftrace_op(op, list) \ + op = rcu_dereference_raw_notrace(list); \ + do + +/* + * Optimized for just a single item in the list (as that is the normal case). + */ +#define while_for_each_ftrace_op(op) \ + while (likely(op = rcu_dereference_raw_notrace((op)->next)) && \ + unlikely((op) != &ftrace_list_end)) + +static inline void ftrace_ops_init(struct ftrace_ops *ops) +{ +#ifdef CONFIG_DYNAMIC_FTRACE + if (!(ops->flags & FTRACE_OPS_FL_INITIALIZED)) { + mutex_init(&ops->regex_lock); + ops->flags |= FTRACE_OPS_FL_INITIALIZED; + } +#endif +} -static void ftrace_list_func(unsigned long ip, unsigned long parent_ip) +/** + * ftrace_nr_registered_ops - return number of ops registered + * + * Returns the number of ftrace_ops registered and tracing functions + */ +int ftrace_nr_registered_ops(void) { - struct ftrace_ops *op = ftrace_list; + struct ftrace_ops *ops; + int cnt = 0; + + mutex_lock(&ftrace_lock); + + for (ops = ftrace_ops_list; + ops != &ftrace_list_end; ops = ops->next) + cnt++; - /* in case someone actually ports this to alpha! */ - read_barrier_depends(); + mutex_unlock(&ftrace_lock); - while (op != &ftrace_list_end) { - /* silly alpha */ - read_barrier_depends(); - op->func(ip, parent_ip); - op = op->next; - }; + return cnt; } -static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip) +static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct pt_regs *regs) { if (!test_tsk_trace_trace(current)) return; - ftrace_pid_function(ip, parent_ip); + ftrace_pid_function(ip, parent_ip, op, regs); } static void set_ftrace_pid_function(ftrace_func_t func) @@ -117,65 +195,142 @@ static void set_ftrace_pid_function(ftrace_func_t func) void clear_ftrace_function(void) { ftrace_trace_function = ftrace_stub; - __ftrace_trace_function = ftrace_stub; ftrace_pid_function = ftrace_stub; } -#ifndef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST -/* - * For those archs that do not test ftrace_trace_stop in their - * mcount call site, we need to do it from C. - */ -static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip) +static void control_ops_disable_all(struct ftrace_ops *ops) { - if (function_trace_stop) - return; + int cpu; - __ftrace_trace_function(ip, parent_ip); + for_each_possible_cpu(cpu) + *per_cpu_ptr(ops->disabled, cpu) = 1; } -#endif -static int __register_ftrace_function(struct ftrace_ops *ops) +static int control_ops_alloc(struct ftrace_ops *ops) +{ + int __percpu *disabled; + + disabled = alloc_percpu(int); + if (!disabled) + return -ENOMEM; + + ops->disabled = disabled; + control_ops_disable_all(ops); + return 0; +} + +static void ftrace_sync(struct work_struct *work) { - ops->next = ftrace_list; /* - * We are entering ops into the ftrace_list but another - * CPU might be walking that list. We need to make sure - * the ops->next pointer is valid before another CPU sees - * the ops pointer included into the ftrace_list. + * This function is just a stub to implement a hard force + * of synchronize_sched(). This requires synchronizing + * tasks even in userspace and idle. + * + * Yes, function tracing is rude. */ - smp_wmb(); - ftrace_list = ops; +} - if (ftrace_enabled) { - ftrace_func_t func; +static void ftrace_sync_ipi(void *data) +{ + /* Probably not needed, but do it anyway */ + smp_rmb(); +} - if (ops->next == &ftrace_list_end) - func = ops->func; - else - func = ftrace_list_func; +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +static void update_function_graph_func(void); +#else +static inline void update_function_graph_func(void) { } +#endif - if (ftrace_pid_trace) { - set_ftrace_pid_function(func); - func = ftrace_pid_func; - } +static void update_ftrace_function(void) +{ + ftrace_func_t func; + + /* + * If we are at the end of the list and this ops is + * recursion safe and not dynamic and the arch supports passing ops, + * then have the mcount trampoline call the function directly. + */ + if (ftrace_ops_list == &ftrace_list_end || + (ftrace_ops_list->next == &ftrace_list_end && + !(ftrace_ops_list->flags & FTRACE_OPS_FL_DYNAMIC) && + (ftrace_ops_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) && + !FTRACE_FORCE_LIST_FUNC)) { + /* Set the ftrace_ops that the arch callback uses */ + set_function_trace_op = ftrace_ops_list; + func = ftrace_ops_list->func; + } else { + /* Just use the default ftrace_ops */ + set_function_trace_op = &ftrace_list_end; + func = ftrace_ops_list_func; + } + + update_function_graph_func(); + + /* If there's no change, then do nothing more here */ + if (ftrace_trace_function == func) + return; + /* + * If we are using the list function, it doesn't care + * about the function_trace_ops. + */ + if (func == ftrace_ops_list_func) { + ftrace_trace_function = func; /* - * For one func, simply call it directly. - * For more than one func, call the chain. + * Don't even bother setting function_trace_ops, + * it would be racy to do so anyway. */ -#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST - ftrace_trace_function = func; -#else - __ftrace_trace_function = func; - ftrace_trace_function = ftrace_test_stop_func; -#endif + return; } - return 0; +#ifndef CONFIG_DYNAMIC_FTRACE + /* + * For static tracing, we need to be a bit more careful. + * The function change takes affect immediately. Thus, + * we need to coorditate the setting of the function_trace_ops + * with the setting of the ftrace_trace_function. + * + * Set the function to the list ops, which will call the + * function we want, albeit indirectly, but it handles the + * ftrace_ops and doesn't depend on function_trace_op. + */ + ftrace_trace_function = ftrace_ops_list_func; + /* + * Make sure all CPUs see this. Yes this is slow, but static + * tracing is slow and nasty to have enabled. + */ + schedule_on_each_cpu(ftrace_sync); + /* Now all cpus are using the list ops. */ + function_trace_op = set_function_trace_op; + /* Make sure the function_trace_op is visible on all CPUs */ + smp_wmb(); + /* Nasty way to force a rmb on all cpus */ + smp_call_function(ftrace_sync_ipi, NULL, 1); + /* OK, we are all set to update the ftrace_trace_function now! */ +#endif /* !CONFIG_DYNAMIC_FTRACE */ + + ftrace_trace_function = func; } -static int __unregister_ftrace_function(struct ftrace_ops *ops) +int using_ftrace_ops_list_func(void) +{ + return ftrace_trace_function == ftrace_ops_list_func; +} + +static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) +{ + ops->next = *list; + /* + * We are entering ops into the list but another + * CPU might be walking that list. We need to make sure + * the ops->next pointer is valid before another CPU sees + * the ops pointer included into the list. + */ + rcu_assign_pointer(*list, ops); +} + +static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) { struct ftrace_ops **p; @@ -183,13 +338,12 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) * If we are removing the last function, then simply point * to the ftrace_stub. */ - if (ftrace_list == ops && ops->next == &ftrace_list_end) { - ftrace_trace_function = ftrace_stub; - ftrace_list = &ftrace_list_end; + if (*list == ops && ops->next == &ftrace_list_end) { + *list = &ftrace_list_end; return 0; } - for (p = &ftrace_list; *p != &ftrace_list_end; p = &(*p)->next) + for (p = list; *p != &ftrace_list_end; p = &(*p)->next) if (*p == ops) break; @@ -197,49 +351,96 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) return -1; *p = (*p)->next; + return 0; +} - if (ftrace_enabled) { - /* If we only have one func left, then call that directly */ - if (ftrace_list->next == &ftrace_list_end) { - ftrace_func_t func = ftrace_list->func; +static void add_ftrace_list_ops(struct ftrace_ops **list, + struct ftrace_ops *main_ops, + struct ftrace_ops *ops) +{ + int first = *list == &ftrace_list_end; + add_ftrace_ops(list, ops); + if (first) + add_ftrace_ops(&ftrace_ops_list, main_ops); +} - if (ftrace_pid_trace) { - set_ftrace_pid_function(func); - func = ftrace_pid_func; - } -#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST - ftrace_trace_function = func; -#else - __ftrace_trace_function = func; +static int remove_ftrace_list_ops(struct ftrace_ops **list, + struct ftrace_ops *main_ops, + struct ftrace_ops *ops) +{ + int ret = remove_ftrace_ops(list, ops); + if (!ret && *list == &ftrace_list_end) + ret = remove_ftrace_ops(&ftrace_ops_list, main_ops); + return ret; +} + +static int __register_ftrace_function(struct ftrace_ops *ops) +{ + if (ops->flags & FTRACE_OPS_FL_DELETED) + return -EINVAL; + + if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED)) + return -EBUSY; + +#ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS + /* + * If the ftrace_ops specifies SAVE_REGS, then it only can be used + * if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set. + * Setting SAVE_REGS_IF_SUPPORTED makes SAVE_REGS irrelevant. + */ + if (ops->flags & FTRACE_OPS_FL_SAVE_REGS && + !(ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)) + return -EINVAL; + + if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED) + ops->flags |= FTRACE_OPS_FL_SAVE_REGS; #endif - } - } + + if (!core_kernel_data((unsigned long)ops)) + ops->flags |= FTRACE_OPS_FL_DYNAMIC; + + if (ops->flags & FTRACE_OPS_FL_CONTROL) { + if (control_ops_alloc(ops)) + return -ENOMEM; + add_ftrace_list_ops(&ftrace_control_list, &control_ops, ops); + } else + add_ftrace_ops(&ftrace_ops_list, ops); + + if (ftrace_enabled) + update_ftrace_function(); return 0; } -static void ftrace_update_pid_func(void) +static int __unregister_ftrace_function(struct ftrace_ops *ops) { - ftrace_func_t func; + int ret; - if (ftrace_trace_function == ftrace_stub) - return; + if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) + return -EBUSY; - func = ftrace_trace_function; + if (ops->flags & FTRACE_OPS_FL_CONTROL) { + ret = remove_ftrace_list_ops(&ftrace_control_list, + &control_ops, ops); + } else + ret = remove_ftrace_ops(&ftrace_ops_list, ops); - if (ftrace_pid_trace) { - set_ftrace_pid_function(func); - func = ftrace_pid_func; - } else { - if (func == ftrace_pid_func) - func = ftrace_pid_function; - } + if (ret < 0) + return ret; -#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST - ftrace_trace_function = func; -#else - __ftrace_trace_function = func; -#endif + if (ftrace_enabled) + update_ftrace_function(); + + return 0; +} + +static void ftrace_update_pid_func(void) +{ + /* Only do something if we are tracing something */ + if (ftrace_trace_function == ftrace_stub) + return; + + update_ftrace_function(); } #ifdef CONFIG_FUNCTION_PROFILER @@ -249,6 +450,7 @@ struct ftrace_profile { unsigned long counter; #ifdef CONFIG_FUNCTION_GRAPH_TRACER unsigned long long time; + unsigned long long time_squared; #endif }; @@ -272,7 +474,6 @@ struct ftrace_profile_stat { #define PROFILES_PER_PAGE \ (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) -static int ftrace_profile_bits __read_mostly; static int ftrace_profile_enabled __read_mostly; /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ @@ -280,7 +481,8 @@ static DEFINE_MUTEX(ftrace_profile_lock); static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); -#define FTRACE_PROFILE_HASH_SIZE 1024 /* must be power of 2 */ +#define FTRACE_PROFILE_HASH_BITS 10 +#define FTRACE_PROFILE_HASH_SIZE (1 << FTRACE_PROFILE_HASH_BITS) static void * function_stat_next(void *v, int idx) @@ -351,9 +553,9 @@ static int function_stat_headers(struct seq_file *m) { #ifdef CONFIG_FUNCTION_GRAPH_TRACER seq_printf(m, " Function " - "Hit Time Avg\n" + "Hit Time Avg s^2\n" " -------- " - "--- ---- ---\n"); + "--- ---- --- ---\n"); #else seq_printf(m, " Function Hit\n" " -------- ---\n"); @@ -365,11 +567,19 @@ static int function_stat_show(struct seq_file *m, void *v) { struct ftrace_profile *rec = v; char str[KSYM_SYMBOL_LEN]; + int ret = 0; #ifdef CONFIG_FUNCTION_GRAPH_TRACER - static DEFINE_MUTEX(mutex); static struct trace_seq s; unsigned long long avg; + unsigned long long stddev; #endif + mutex_lock(&ftrace_profile_lock); + + /* we raced with function_profile_reset() */ + if (unlikely(rec->counter == 0)) { + ret = -EBUSY; + goto out; + } kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); seq_printf(m, " %-30.30s %10lu", str, rec->counter); @@ -379,17 +589,37 @@ static int function_stat_show(struct seq_file *m, void *v) avg = rec->time; do_div(avg, rec->counter); - mutex_lock(&mutex); + /* Sample standard deviation (s^2) */ + if (rec->counter <= 1) + stddev = 0; + else { + /* + * Apply Welford's method: + * s^2 = 1 / (n * (n-1)) * (n * \Sum (x_i)^2 - (\Sum x_i)^2) + */ + stddev = rec->counter * rec->time_squared - + rec->time * rec->time; + + /* + * Divide only 1000 for ns^2 -> us^2 conversion. + * trace_print_graph_duration will divide 1000 again. + */ + do_div(stddev, rec->counter * (rec->counter - 1) * 1000); + } + trace_seq_init(&s); trace_print_graph_duration(rec->time, &s); trace_seq_puts(&s, " "); trace_print_graph_duration(avg, &s); + trace_seq_puts(&s, " "); + trace_print_graph_duration(stddev, &s); trace_print_seq(m, &s); - mutex_unlock(&mutex); #endif seq_putc(m, '\n'); +out: + mutex_unlock(&ftrace_profile_lock); - return 0; + return ret; } static void ftrace_profile_reset(struct ftrace_profile_stat *stat) @@ -440,7 +670,7 @@ int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); - for (i = 0; i < pages; i++) { + for (i = 1; i < pages; i++) { pg->next = (void *)get_zeroed_page(GFP_KERNEL); if (!pg->next) goto out_free; @@ -458,7 +688,6 @@ int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) free_page(tmp); } - free_page((unsigned long)stat->pages); stat->pages = NULL; stat->start = NULL; @@ -489,13 +718,6 @@ static int ftrace_profile_init_cpu(int cpu) if (!stat->hash) return -ENOMEM; - if (!ftrace_profile_bits) { - size--; - - for (; size; size >>= 1) - ftrace_profile_bits++; - } - /* Preallocate the function profiling pages */ if (ftrace_profile_pages_init(stat) < 0) { kfree(stat->hash); @@ -511,7 +733,7 @@ static int ftrace_profile_init(void) int cpu; int ret = 0; - for_each_online_cpu(cpu) { + for_each_possible_cpu(cpu) { ret = ftrace_profile_init_cpu(cpu); if (ret) break; @@ -526,16 +748,15 @@ ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) { struct ftrace_profile *rec; struct hlist_head *hhd; - struct hlist_node *n; unsigned long key; - key = hash_long(ip, ftrace_profile_bits); + key = hash_long(ip, FTRACE_PROFILE_HASH_BITS); hhd = &stat->hash[key]; if (hlist_empty(hhd)) return NULL; - hlist_for_each_entry_rcu(rec, n, hhd, node) { + hlist_for_each_entry_rcu_notrace(rec, hhd, node) { if (rec->ip == ip) return rec; } @@ -548,7 +769,7 @@ static void ftrace_add_profile(struct ftrace_profile_stat *stat, { unsigned long key; - key = hash_long(rec->ip, ftrace_profile_bits); + key = hash_long(rec->ip, FTRACE_PROFILE_HASH_BITS); hlist_add_head_rcu(&rec->node, &stat->hash[key]); } @@ -589,7 +810,8 @@ ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) } static void -function_profile_call(unsigned long ip, unsigned long parent_ip) +function_profile_call(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *ops, struct pt_regs *regs) { struct ftrace_profile_stat *stat; struct ftrace_profile *rec; @@ -600,7 +822,7 @@ function_profile_call(unsigned long ip, unsigned long parent_ip) local_irq_save(flags); - stat = &__get_cpu_var(ftrace_profile_stats); + stat = this_cpu_ptr(&ftrace_profile_stats); if (!stat->hash || !ftrace_profile_enabled) goto out; @@ -619,7 +841,7 @@ function_profile_call(unsigned long ip, unsigned long parent_ip) #ifdef CONFIG_FUNCTION_GRAPH_TRACER static int profile_graph_entry(struct ftrace_graph_ent *trace) { - function_profile_call(trace->func, 0); + function_profile_call(trace->func, 0, NULL, NULL); return 1; } @@ -631,10 +853,14 @@ static void profile_graph_return(struct ftrace_graph_ret *trace) unsigned long flags; local_irq_save(flags); - stat = &__get_cpu_var(ftrace_profile_stats); + stat = this_cpu_ptr(&ftrace_profile_stats); if (!stat->hash || !ftrace_profile_enabled) goto out; + /* If the calltime was zero'd ignore it */ + if (!trace->calltime) + goto out; + calltime = trace->rettime - trace->calltime; if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) { @@ -653,8 +879,10 @@ static void profile_graph_return(struct ftrace_graph_ret *trace) } rec = ftrace_find_profiled_func(stat, trace->func); - if (rec) + if (rec) { rec->time += calltime; + rec->time_squared += calltime * calltime; + } out: local_irq_restore(flags); @@ -671,9 +899,10 @@ static void unregister_ftrace_profiler(void) unregister_ftrace_graph(); } #else -static struct ftrace_ops ftrace_profile_ops __read_mostly = -{ +static struct ftrace_ops ftrace_profile_ops __read_mostly = { .func = function_profile_call, + .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, + INIT_REGEX_LOCK(ftrace_profile_ops) }; static int register_ftrace_profiler(void) @@ -692,19 +921,10 @@ ftrace_profile_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { unsigned long val; - char buf[64]; /* big enough to hold a number */ int ret; - if (cnt >= sizeof(buf)) - return -EINVAL; - - if (copy_from_user(&buf, ubuf, cnt)) - return -EFAULT; - - buf[cnt] = 0; - - ret = strict_strtoul(buf, 10, &val); - if (ret < 0) + ret = kstrtoul_from_user(ubuf, cnt, 10, &val); + if (ret) return ret; val = !!val; @@ -736,7 +956,7 @@ ftrace_profile_write(struct file *filp, const char __user *ubuf, out: mutex_unlock(&ftrace_profile_lock); - filp->f_pos += cnt; + *ppos += cnt; return cnt; } @@ -756,6 +976,7 @@ static const struct file_operations ftrace_profile_fops = { .open = tracing_open_generic, .read = ftrace_profile_read, .write = ftrace_profile_write, + .llseek = default_llseek, }; /* used to initialize the real stat files */ @@ -768,7 +989,7 @@ static struct tracer_stat function_stats __initdata = { .stat_show = function_stat_show }; -static void ftrace_profile_debugfs(struct dentry *d_tracer) +static __init void ftrace_profile_debugfs(struct dentry *d_tracer) { struct ftrace_profile_stat *stat; struct dentry *entry; @@ -786,7 +1007,6 @@ static void ftrace_profile_debugfs(struct dentry *d_tracer) * The files created are permanent, if something happens * we still do not free memory. */ - kfree(stat); WARN(1, "Could not allocate stat file for cpu %d\n", cpu); @@ -813,13 +1033,11 @@ static void ftrace_profile_debugfs(struct dentry *d_tracer) } #else /* CONFIG_FUNCTION_PROFILER */ -static void ftrace_profile_debugfs(struct dentry *d_tracer) +static __init void ftrace_profile_debugfs(struct dentry *d_tracer) { } #endif /* CONFIG_FUNCTION_PROFILER */ -/* set when tracing only a pid */ -struct pid *ftrace_pid_trace; static struct pid * const ftrace_swapper_pid = &init_struct_pid; #ifdef CONFIG_DYNAMIC_FTRACE @@ -836,33 +1054,50 @@ struct ftrace_func_probe { unsigned long flags; unsigned long ip; void *data; - struct rcu_head rcu; + struct list_head free_list; }; -enum { - FTRACE_ENABLE_CALLS = (1 << 0), - FTRACE_DISABLE_CALLS = (1 << 1), - FTRACE_UPDATE_TRACE_FUNC = (1 << 2), - FTRACE_ENABLE_MCOUNT = (1 << 3), - FTRACE_DISABLE_MCOUNT = (1 << 4), - FTRACE_START_FUNC_RET = (1 << 5), - FTRACE_STOP_FUNC_RET = (1 << 6), +struct ftrace_func_entry { + struct hlist_node hlist; + unsigned long ip; }; -static int ftrace_filtered; - -static struct dyn_ftrace *ftrace_new_addrs; +struct ftrace_hash { + unsigned long size_bits; + struct hlist_head *buckets; + unsigned long count; + struct rcu_head rcu; +}; -static DEFINE_MUTEX(ftrace_regex_lock); +/* + * We make these constant because no one should touch them, + * but they are used as the default "empty hash", to avoid allocating + * it all the time. These are in a read only section such that if + * anyone does try to modify it, it will cause an exception. + */ +static const struct hlist_head empty_buckets[1]; +static const struct ftrace_hash empty_hash = { + .buckets = (struct hlist_head *)empty_buckets, +}; +#define EMPTY_HASH ((struct ftrace_hash *)&empty_hash) + +static struct ftrace_ops global_ops = { + .func = ftrace_stub, + .notrace_hash = EMPTY_HASH, + .filter_hash = EMPTY_HASH, + .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, + INIT_REGEX_LOCK(global_ops) +}; struct ftrace_page { struct ftrace_page *next; + struct dyn_ftrace *records; int index; - struct dyn_ftrace records[]; + int size; }; -#define ENTRIES_PER_PAGE \ - ((PAGE_SIZE - sizeof(struct ftrace_page)) / sizeof(struct dyn_ftrace)) +#define ENTRY_SIZE sizeof(struct dyn_ftrace) +#define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE) /* estimate from running different kernels */ #define NR_TO_INIT 10000 @@ -870,7 +1105,308 @@ struct ftrace_page { static struct ftrace_page *ftrace_pages_start; static struct ftrace_page *ftrace_pages; -static struct dyn_ftrace *ftrace_free_records; +static bool __always_inline ftrace_hash_empty(struct ftrace_hash *hash) +{ + return !hash || !hash->count; +} + +static struct ftrace_func_entry * +ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) +{ + unsigned long key; + struct ftrace_func_entry *entry; + struct hlist_head *hhd; + + if (ftrace_hash_empty(hash)) + return NULL; + + if (hash->size_bits > 0) + key = hash_long(ip, hash->size_bits); + else + key = 0; + + hhd = &hash->buckets[key]; + + hlist_for_each_entry_rcu_notrace(entry, hhd, hlist) { + if (entry->ip == ip) + return entry; + } + return NULL; +} + +static void __add_hash_entry(struct ftrace_hash *hash, + struct ftrace_func_entry *entry) +{ + struct hlist_head *hhd; + unsigned long key; + + if (hash->size_bits) + key = hash_long(entry->ip, hash->size_bits); + else + key = 0; + + hhd = &hash->buckets[key]; + hlist_add_head(&entry->hlist, hhd); + hash->count++; +} + +static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) +{ + struct ftrace_func_entry *entry; + + entry = kmalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return -ENOMEM; + + entry->ip = ip; + __add_hash_entry(hash, entry); + + return 0; +} + +static void +free_hash_entry(struct ftrace_hash *hash, + struct ftrace_func_entry *entry) +{ + hlist_del(&entry->hlist); + kfree(entry); + hash->count--; +} + +static void +remove_hash_entry(struct ftrace_hash *hash, + struct ftrace_func_entry *entry) +{ + hlist_del(&entry->hlist); + hash->count--; +} + +static void ftrace_hash_clear(struct ftrace_hash *hash) +{ + struct hlist_head *hhd; + struct hlist_node *tn; + struct ftrace_func_entry *entry; + int size = 1 << hash->size_bits; + int i; + + if (!hash->count) + return; + + for (i = 0; i < size; i++) { + hhd = &hash->buckets[i]; + hlist_for_each_entry_safe(entry, tn, hhd, hlist) + free_hash_entry(hash, entry); + } + FTRACE_WARN_ON(hash->count); +} + +static void free_ftrace_hash(struct ftrace_hash *hash) +{ + if (!hash || hash == EMPTY_HASH) + return; + ftrace_hash_clear(hash); + kfree(hash->buckets); + kfree(hash); +} + +static void __free_ftrace_hash_rcu(struct rcu_head *rcu) +{ + struct ftrace_hash *hash; + + hash = container_of(rcu, struct ftrace_hash, rcu); + free_ftrace_hash(hash); +} + +static void free_ftrace_hash_rcu(struct ftrace_hash *hash) +{ + if (!hash || hash == EMPTY_HASH) + return; + call_rcu_sched(&hash->rcu, __free_ftrace_hash_rcu); +} + +void ftrace_free_filter(struct ftrace_ops *ops) +{ + ftrace_ops_init(ops); + free_ftrace_hash(ops->filter_hash); + free_ftrace_hash(ops->notrace_hash); +} + +static struct ftrace_hash *alloc_ftrace_hash(int size_bits) +{ + struct ftrace_hash *hash; + int size; + + hash = kzalloc(sizeof(*hash), GFP_KERNEL); + if (!hash) + return NULL; + + size = 1 << size_bits; + hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL); + + if (!hash->buckets) { + kfree(hash); + return NULL; + } + + hash->size_bits = size_bits; + + return hash; +} + +static struct ftrace_hash * +alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) +{ + struct ftrace_func_entry *entry; + struct ftrace_hash *new_hash; + int size; + int ret; + int i; + + new_hash = alloc_ftrace_hash(size_bits); + if (!new_hash) + return NULL; + + /* Empty hash? */ + if (ftrace_hash_empty(hash)) + return new_hash; + + size = 1 << hash->size_bits; + for (i = 0; i < size; i++) { + hlist_for_each_entry(entry, &hash->buckets[i], hlist) { + ret = add_hash_entry(new_hash, entry->ip); + if (ret < 0) + goto free_hash; + } + } + + FTRACE_WARN_ON(new_hash->count != hash->count); + + return new_hash; + + free_hash: + free_ftrace_hash(new_hash); + return NULL; +} + +static void +ftrace_hash_rec_disable(struct ftrace_ops *ops, int filter_hash); +static void +ftrace_hash_rec_enable(struct ftrace_ops *ops, int filter_hash); + +static int +ftrace_hash_move(struct ftrace_ops *ops, int enable, + struct ftrace_hash **dst, struct ftrace_hash *src) +{ + struct ftrace_func_entry *entry; + struct hlist_node *tn; + struct hlist_head *hhd; + struct ftrace_hash *old_hash; + struct ftrace_hash *new_hash; + int size = src->count; + int bits = 0; + int ret; + int i; + + /* + * Remove the current set, update the hash and add + * them back. + */ + ftrace_hash_rec_disable(ops, enable); + + /* + * If the new source is empty, just free dst and assign it + * the empty_hash. + */ + if (!src->count) { + free_ftrace_hash_rcu(*dst); + rcu_assign_pointer(*dst, EMPTY_HASH); + /* still need to update the function records */ + ret = 0; + goto out; + } + + /* + * Make the hash size about 1/2 the # found + */ + for (size /= 2; size; size >>= 1) + bits++; + + /* Don't allocate too much */ + if (bits > FTRACE_HASH_MAX_BITS) + bits = FTRACE_HASH_MAX_BITS; + + ret = -ENOMEM; + new_hash = alloc_ftrace_hash(bits); + if (!new_hash) + goto out; + + size = 1 << src->size_bits; + for (i = 0; i < size; i++) { + hhd = &src->buckets[i]; + hlist_for_each_entry_safe(entry, tn, hhd, hlist) { + remove_hash_entry(src, entry); + __add_hash_entry(new_hash, entry); + } + } + + old_hash = *dst; + rcu_assign_pointer(*dst, new_hash); + free_ftrace_hash_rcu(old_hash); + + ret = 0; + out: + /* + * Enable regardless of ret: + * On success, we enable the new hash. + * On failure, we re-enable the original hash. + */ + ftrace_hash_rec_enable(ops, enable); + + return ret; +} + +/* + * Test the hashes for this ops to see if we want to call + * the ops->func or not. + * + * It's a match if the ip is in the ops->filter_hash or + * the filter_hash does not exist or is empty, + * AND + * the ip is not in the ops->notrace_hash. + * + * This needs to be called with preemption disabled as + * the hashes are freed with call_rcu_sched(). + */ +static int +ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs) +{ + struct ftrace_hash *filter_hash; + struct ftrace_hash *notrace_hash; + int ret; + +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS + /* + * There's a small race when adding ops that the ftrace handler + * that wants regs, may be called without them. We can not + * allow that handler to be called if regs is NULL. + */ + if (regs == NULL && (ops->flags & FTRACE_OPS_FL_SAVE_REGS)) + return 0; +#endif + + filter_hash = rcu_dereference_raw_notrace(ops->filter_hash); + notrace_hash = rcu_dereference_raw_notrace(ops->notrace_hash); + + if ((ftrace_hash_empty(filter_hash) || + ftrace_lookup_ip(filter_hash, ip)) && + (ftrace_hash_empty(notrace_hash) || + !ftrace_lookup_ip(notrace_hash, ip))) + ret = 1; + else + ret = 0; + + return ret; +} /* * This is a double for. Do not use 'break' to break out of the loop, @@ -886,93 +1422,186 @@ static struct dyn_ftrace *ftrace_free_records; } \ } -#ifdef CONFIG_KPROBES - -static int frozen_record_count; -static inline void freeze_record(struct dyn_ftrace *rec) +static int ftrace_cmp_recs(const void *a, const void *b) { - if (!(rec->flags & FTRACE_FL_FROZEN)) { - rec->flags |= FTRACE_FL_FROZEN; - frozen_record_count++; - } + const struct dyn_ftrace *key = a; + const struct dyn_ftrace *rec = b; + + if (key->flags < rec->ip) + return -1; + if (key->ip >= rec->ip + MCOUNT_INSN_SIZE) + return 1; + return 0; } -static inline void unfreeze_record(struct dyn_ftrace *rec) +static unsigned long ftrace_location_range(unsigned long start, unsigned long end) { - if (rec->flags & FTRACE_FL_FROZEN) { - rec->flags &= ~FTRACE_FL_FROZEN; - frozen_record_count--; + struct ftrace_page *pg; + struct dyn_ftrace *rec; + struct dyn_ftrace key; + + key.ip = start; + key.flags = end; /* overload flags, as it is unsigned long */ + + for (pg = ftrace_pages_start; pg; pg = pg->next) { + if (end < pg->records[0].ip || + start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) + continue; + rec = bsearch(&key, pg->records, pg->index, + sizeof(struct dyn_ftrace), + ftrace_cmp_recs); + if (rec) + return rec->ip; } + + return 0; } -static inline int record_frozen(struct dyn_ftrace *rec) +/** + * ftrace_location - return true if the ip giving is a traced location + * @ip: the instruction pointer to check + * + * Returns rec->ip if @ip given is a pointer to a ftrace location. + * That is, the instruction that is either a NOP or call to + * the function tracer. It checks the ftrace internal tables to + * determine if the address belongs or not. + */ +unsigned long ftrace_location(unsigned long ip) { - return rec->flags & FTRACE_FL_FROZEN; + return ftrace_location_range(ip, ip); } -#else -# define freeze_record(rec) ({ 0; }) -# define unfreeze_record(rec) ({ 0; }) -# define record_frozen(rec) ({ 0; }) -#endif /* CONFIG_KPROBES */ -static void ftrace_free_rec(struct dyn_ftrace *rec) +/** + * ftrace_text_reserved - return true if range contains an ftrace location + * @start: start of range to search + * @end: end of range to search (inclusive). @end points to the last byte to check. + * + * Returns 1 if @start and @end contains a ftrace location. + * That is, the instruction that is either a NOP or call to + * the function tracer. It checks the ftrace internal tables to + * determine if the address belongs or not. + */ +int ftrace_text_reserved(const void *start, const void *end) { - rec->freelist = ftrace_free_records; - ftrace_free_records = rec; - rec->flags |= FTRACE_FL_FREE; + unsigned long ret; + + ret = ftrace_location_range((unsigned long)start, + (unsigned long)end); + + return (int)!!ret; } -static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip) +static void __ftrace_hash_rec_update(struct ftrace_ops *ops, + int filter_hash, + bool inc) { + struct ftrace_hash *hash; + struct ftrace_hash *other_hash; + struct ftrace_page *pg; struct dyn_ftrace *rec; + int count = 0; + int all = 0; - /* First check for freed records */ - if (ftrace_free_records) { - rec = ftrace_free_records; - - if (unlikely(!(rec->flags & FTRACE_FL_FREE))) { - FTRACE_WARN_ON_ONCE(1); - ftrace_free_records = NULL; - return NULL; - } + /* Only update if the ops has been registered */ + if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) + return; - ftrace_free_records = rec->freelist; - memset(rec, 0, sizeof(*rec)); - return rec; + /* + * In the filter_hash case: + * If the count is zero, we update all records. + * Otherwise we just update the items in the hash. + * + * In the notrace_hash case: + * We enable the update in the hash. + * As disabling notrace means enabling the tracing, + * and enabling notrace means disabling, the inc variable + * gets inversed. + */ + if (filter_hash) { + hash = ops->filter_hash; + other_hash = ops->notrace_hash; + if (ftrace_hash_empty(hash)) + all = 1; + } else { + inc = !inc; + hash = ops->notrace_hash; + other_hash = ops->filter_hash; + /* + * If the notrace hash has no items, + * then there's nothing to do. + */ + if (ftrace_hash_empty(hash)) + return; } - if (ftrace_pages->index == ENTRIES_PER_PAGE) { - if (!ftrace_pages->next) { - /* allocate another page */ - ftrace_pages->next = - (void *)get_zeroed_page(GFP_KERNEL); - if (!ftrace_pages->next) - return NULL; + do_for_each_ftrace_rec(pg, rec) { + int in_other_hash = 0; + int in_hash = 0; + int match = 0; + + if (all) { + /* + * Only the filter_hash affects all records. + * Update if the record is not in the notrace hash. + */ + if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip)) + match = 1; + } else { + in_hash = !!ftrace_lookup_ip(hash, rec->ip); + in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip); + + /* + * If filter_hash is set, we want to match all functions + * that are in the hash but not in the other hash. + * + * If filter_hash is not set, then we are decrementing. + * That means we match anything that is in the hash + * and also in the other_hash. That is, we need to turn + * off functions in the other hash because they are disabled + * by this hash. + */ + if (filter_hash && in_hash && !in_other_hash) + match = 1; + else if (!filter_hash && in_hash && + (in_other_hash || ftrace_hash_empty(other_hash))) + match = 1; } - ftrace_pages = ftrace_pages->next; - } + if (!match) + continue; - return &ftrace_pages->records[ftrace_pages->index++]; + if (inc) { + rec->flags++; + if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == FTRACE_REF_MAX)) + return; + /* + * If any ops wants regs saved for this function + * then all ops will get saved regs. + */ + if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) + rec->flags |= FTRACE_FL_REGS; + } else { + if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == 0)) + return; + rec->flags--; + } + count++; + /* Shortcut, if we handled all records, we are done. */ + if (!all && count == hash->count) + return; + } while_for_each_ftrace_rec(); } -static struct dyn_ftrace * -ftrace_record_ip(unsigned long ip) +static void ftrace_hash_rec_disable(struct ftrace_ops *ops, + int filter_hash) { - struct dyn_ftrace *rec; - - if (ftrace_disabled) - return NULL; - - rec = ftrace_alloc_dyn_node(ip); - if (!rec) - return NULL; - - rec->ip = ip; - rec->newlist = ftrace_new_addrs; - ftrace_new_addrs = rec; + __ftrace_hash_rec_update(ops, filter_hash, 0); +} - return rec; +static void ftrace_hash_rec_enable(struct ftrace_ops *ops, + int filter_hash) +{ + __ftrace_hash_rec_update(ops, filter_hash, 1); } static void print_ip_ins(const char *fmt, unsigned char *p) @@ -985,7 +1614,19 @@ static void print_ip_ins(const char *fmt, unsigned char *p) printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); } -static void ftrace_bug(int failed, unsigned long ip) +/** + * ftrace_bug - report and shutdown function tracer + * @failed: The failed type (EFAULT, EINVAL, EPERM) + * @ip: The address that failed + * + * The arch code that enables or disables the function tracing + * can call ftrace_bug() when it has detected a problem in + * modifying the code. @failed should be one of either: + * EFAULT - if the problem happens on reading the @ip address + * EINVAL - if what is read at @ip is not what was expected + * EPERM - if the problem happens on writting to the @ip address + */ +void ftrace_bug(int failed, unsigned long ip) { switch (failed) { case -EFAULT: @@ -1012,117 +1653,262 @@ static void ftrace_bug(int failed, unsigned long ip) } } - -static int -__ftrace_replace_code(struct dyn_ftrace *rec, int enable) +static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update) { - unsigned long ftrace_addr; - unsigned long ip, fl; - - ftrace_addr = (unsigned long)FTRACE_ADDR; - - ip = rec->ip; + unsigned long flag = 0UL; /* - * If this record is not to be traced and - * it is not enabled then do nothing. + * If we are updating calls: + * + * If the record has a ref count, then we need to enable it + * because someone is using it. * - * If this record is not to be traced and - * it is enabled then disable it. + * Otherwise we make sure its disabled. * + * If we are disabling calls, then disable all records that + * are enabled. */ - if (rec->flags & FTRACE_FL_NOTRACE) { - if (rec->flags & FTRACE_FL_ENABLED) - rec->flags &= ~FTRACE_FL_ENABLED; - else - return 0; + if (enable && (rec->flags & ~FTRACE_FL_MASK)) + flag = FTRACE_FL_ENABLED; + + /* + * If enabling and the REGS flag does not match the REGS_EN, then + * do not ignore this record. Set flags to fail the compare against + * ENABLED. + */ + if (flag && + (!(rec->flags & FTRACE_FL_REGS) != !(rec->flags & FTRACE_FL_REGS_EN))) + flag |= FTRACE_FL_REGS; + + /* If the state of this record hasn't changed, then do nothing */ + if ((rec->flags & FTRACE_FL_ENABLED) == flag) + return FTRACE_UPDATE_IGNORE; + + if (flag) { + /* Save off if rec is being enabled (for return value) */ + flag ^= rec->flags & FTRACE_FL_ENABLED; + + if (update) { + rec->flags |= FTRACE_FL_ENABLED; + if (flag & FTRACE_FL_REGS) { + if (rec->flags & FTRACE_FL_REGS) + rec->flags |= FTRACE_FL_REGS_EN; + else + rec->flags &= ~FTRACE_FL_REGS_EN; + } + } - } else if (ftrace_filtered && enable) { /* - * Filtering is on: + * If this record is being updated from a nop, then + * return UPDATE_MAKE_CALL. + * Otherwise, + * return UPDATE_MODIFY_CALL to tell the caller to convert + * from the save regs, to a non-save regs function or + * vice versa. */ + if (flag & FTRACE_FL_ENABLED) + return FTRACE_UPDATE_MAKE_CALL; - fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED); + return FTRACE_UPDATE_MODIFY_CALL; + } - /* Record is filtered and enabled, do nothing */ - if (fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED)) - return 0; + if (update) { + /* If there's no more users, clear all flags */ + if (!(rec->flags & ~FTRACE_FL_MASK)) + rec->flags = 0; + else + /* Just disable the record (keep REGS state) */ + rec->flags &= ~FTRACE_FL_ENABLED; + } - /* Record is not filtered or enabled, do nothing */ - if (!fl) - return 0; + return FTRACE_UPDATE_MAKE_NOP; +} - /* Record is not filtered but enabled, disable it */ - if (fl == FTRACE_FL_ENABLED) - rec->flags &= ~FTRACE_FL_ENABLED; - else - /* Otherwise record is filtered but not enabled, enable it */ - rec->flags |= FTRACE_FL_ENABLED; - } else { - /* Disable or not filtered */ +/** + * ftrace_update_record, set a record that now is tracing or not + * @rec: the record to update + * @enable: set to 1 if the record is tracing, zero to force disable + * + * The records that represent all functions that can be traced need + * to be updated when tracing has been enabled. + */ +int ftrace_update_record(struct dyn_ftrace *rec, int enable) +{ + return ftrace_check_record(rec, enable, 1); +} - if (enable) { - /* if record is enabled, do nothing */ - if (rec->flags & FTRACE_FL_ENABLED) - return 0; +/** + * ftrace_test_record, check if the record has been enabled or not + * @rec: the record to test + * @enable: set to 1 to check if enabled, 0 if it is disabled + * + * The arch code may need to test if a record is already set to + * tracing to determine how to modify the function code that it + * represents. + */ +int ftrace_test_record(struct dyn_ftrace *rec, int enable) +{ + return ftrace_check_record(rec, enable, 0); +} - rec->flags |= FTRACE_FL_ENABLED; +/** + * ftrace_get_addr_new - Get the call address to set to + * @rec: The ftrace record descriptor + * + * If the record has the FTRACE_FL_REGS set, that means that it + * wants to convert to a callback that saves all regs. If FTRACE_FL_REGS + * is not not set, then it wants to convert to the normal callback. + * + * Returns the address of the trampoline to set to + */ +unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec) +{ + if (rec->flags & FTRACE_FL_REGS) + return (unsigned long)FTRACE_REGS_ADDR; + else + return (unsigned long)FTRACE_ADDR; +} - } else { +/** + * ftrace_get_addr_curr - Get the call address that is already there + * @rec: The ftrace record descriptor + * + * The FTRACE_FL_REGS_EN is set when the record already points to + * a function that saves all the regs. Basically the '_EN' version + * represents the current state of the function. + * + * Returns the address of the trampoline that is currently being called + */ +unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec) +{ + if (rec->flags & FTRACE_FL_REGS_EN) + return (unsigned long)FTRACE_REGS_ADDR; + else + return (unsigned long)FTRACE_ADDR; +} - /* if record is not enabled, do nothing */ - if (!(rec->flags & FTRACE_FL_ENABLED)) - return 0; +static int +__ftrace_replace_code(struct dyn_ftrace *rec, int enable) +{ + unsigned long ftrace_old_addr; + unsigned long ftrace_addr; + int ret; - rec->flags &= ~FTRACE_FL_ENABLED; - } - } + ftrace_addr = ftrace_get_addr_new(rec); + + /* This needs to be done before we call ftrace_update_record */ + ftrace_old_addr = ftrace_get_addr_curr(rec); + + ret = ftrace_update_record(rec, enable); - if (rec->flags & FTRACE_FL_ENABLED) + switch (ret) { + case FTRACE_UPDATE_IGNORE: + return 0; + + case FTRACE_UPDATE_MAKE_CALL: return ftrace_make_call(rec, ftrace_addr); - else + + case FTRACE_UPDATE_MAKE_NOP: return ftrace_make_nop(NULL, rec, ftrace_addr); + + case FTRACE_UPDATE_MODIFY_CALL: + return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr); + } + + return -1; /* unknow ftrace bug */ } -static void ftrace_replace_code(int enable) +void __weak ftrace_replace_code(int enable) { struct dyn_ftrace *rec; struct ftrace_page *pg; int failed; - do_for_each_ftrace_rec(pg, rec) { - /* - * Skip over free records, records that have - * failed and not converted. - */ - if (rec->flags & FTRACE_FL_FREE || - rec->flags & FTRACE_FL_FAILED || - !(rec->flags & FTRACE_FL_CONVERTED)) - continue; - - /* ignore updates to this record's mcount site */ - if (get_kprobe((void *)rec->ip)) { - freeze_record(rec); - continue; - } else { - unfreeze_record(rec); - } + if (unlikely(ftrace_disabled)) + return; + do_for_each_ftrace_rec(pg, rec) { failed = __ftrace_replace_code(rec, enable); if (failed) { - rec->flags |= FTRACE_FL_FAILED; - if ((system_state == SYSTEM_BOOTING) || - !core_kernel_text(rec->ip)) { - ftrace_free_rec(rec); - } else { - ftrace_bug(failed, rec->ip); - /* Stop processing */ - return; - } + ftrace_bug(failed, rec->ip); + /* Stop processing */ + return; } } while_for_each_ftrace_rec(); } +struct ftrace_rec_iter { + struct ftrace_page *pg; + int index; +}; + +/** + * ftrace_rec_iter_start, start up iterating over traced functions + * + * Returns an iterator handle that is used to iterate over all + * the records that represent address locations where functions + * are traced. + * + * May return NULL if no records are available. + */ +struct ftrace_rec_iter *ftrace_rec_iter_start(void) +{ + /* + * We only use a single iterator. + * Protected by the ftrace_lock mutex. + */ + static struct ftrace_rec_iter ftrace_rec_iter; + struct ftrace_rec_iter *iter = &ftrace_rec_iter; + + iter->pg = ftrace_pages_start; + iter->index = 0; + + /* Could have empty pages */ + while (iter->pg && !iter->pg->index) + iter->pg = iter->pg->next; + + if (!iter->pg) + return NULL; + + return iter; +} + +/** + * ftrace_rec_iter_next, get the next record to process. + * @iter: The handle to the iterator. + * + * Returns the next iterator after the given iterator @iter. + */ +struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter) +{ + iter->index++; + + if (iter->index >= iter->pg->index) { + iter->pg = iter->pg->next; + iter->index = 0; + + /* Could have empty pages */ + while (iter->pg && !iter->pg->index) + iter->pg = iter->pg->next; + } + + if (!iter->pg) + return NULL; + + return iter; +} + +/** + * ftrace_rec_iter_record, get the record at the iterator location + * @iter: The current iterator location + * + * Returns the record that the current @iter is at. + */ +struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter) +{ + return &iter->pg->records[iter->index]; +} + static int ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) { @@ -1131,10 +1917,12 @@ ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) ip = rec->ip; + if (unlikely(ftrace_disabled)) + return 0; + ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); if (ret) { ftrace_bug(ret, ip); - rec->flags |= FTRACE_FL_FAILED; return 0; } return 1; @@ -1158,26 +1946,83 @@ int __weak ftrace_arch_code_modify_post_process(void) return 0; } -static int __ftrace_modify_code(void *data) +void ftrace_modify_all_code(int command) { - int *command = data; + int update = command & FTRACE_UPDATE_TRACE_FUNC; + int err = 0; - if (*command & FTRACE_ENABLE_CALLS) + /* + * If the ftrace_caller calls a ftrace_ops func directly, + * we need to make sure that it only traces functions it + * expects to trace. When doing the switch of functions, + * we need to update to the ftrace_ops_list_func first + * before the transition between old and new calls are set, + * as the ftrace_ops_list_func will check the ops hashes + * to make sure the ops are having the right functions + * traced. + */ + if (update) { + err = ftrace_update_ftrace_func(ftrace_ops_list_func); + if (FTRACE_WARN_ON(err)) + return; + } + + if (command & FTRACE_UPDATE_CALLS) ftrace_replace_code(1); - else if (*command & FTRACE_DISABLE_CALLS) + else if (command & FTRACE_DISABLE_CALLS) ftrace_replace_code(0); - if (*command & FTRACE_UPDATE_TRACE_FUNC) - ftrace_update_ftrace_func(ftrace_trace_function); + if (update && ftrace_trace_function != ftrace_ops_list_func) { + function_trace_op = set_function_trace_op; + smp_wmb(); + /* If irqs are disabled, we are in stop machine */ + if (!irqs_disabled()) + smp_call_function(ftrace_sync_ipi, NULL, 1); + err = ftrace_update_ftrace_func(ftrace_trace_function); + if (FTRACE_WARN_ON(err)) + return; + } - if (*command & FTRACE_START_FUNC_RET) - ftrace_enable_ftrace_graph_caller(); - else if (*command & FTRACE_STOP_FUNC_RET) - ftrace_disable_ftrace_graph_caller(); + if (command & FTRACE_START_FUNC_RET) + err = ftrace_enable_ftrace_graph_caller(); + else if (command & FTRACE_STOP_FUNC_RET) + err = ftrace_disable_ftrace_graph_caller(); + FTRACE_WARN_ON(err); +} + +static int __ftrace_modify_code(void *data) +{ + int *command = data; + + ftrace_modify_all_code(*command); return 0; } +/** + * ftrace_run_stop_machine, go back to the stop machine method + * @command: The command to tell ftrace what to do + * + * If an arch needs to fall back to the stop machine method, the + * it can call this function. + */ +void ftrace_run_stop_machine(int command) +{ + stop_machine(__ftrace_modify_code, &command, NULL); +} + +/** + * arch_ftrace_update_code, modify the code to trace or not trace + * @command: The command that needs to be done + * + * Archs can override this function if it does not need to + * run stop_machine() to modify code. + */ +void __weak arch_ftrace_update_code(int command) +{ + ftrace_run_stop_machine(command); +} + static void ftrace_run_update_code(int command) { int ret; @@ -1186,8 +2031,21 @@ static void ftrace_run_update_code(int command) FTRACE_WARN_ON(ret); if (ret) return; + /* + * Do not call function tracer while we update the code. + * We are in stop machine. + */ + function_trace_stop++; - stop_machine(__ftrace_modify_code, &command, NULL); + /* + * By default we use stop_machine() to modify the code. + * But archs can do what ever they want as long as it + * is safe. The stop_machine() is the safest, but also + * produces the most overhead. + */ + arch_ftrace_update_code(command); + + function_trace_stop--; ret = ftrace_arch_code_modify_post_process(); FTRACE_WARN_ON(ret); @@ -1195,6 +2053,12 @@ static void ftrace_run_update_code(int command) static ftrace_func_t saved_ftrace_func; static int ftrace_start_up; +static int global_start_up; + +static void control_ops_free(struct ftrace_ops *ops) +{ + free_percpu(ops->disabled); +} static void ftrace_startup_enable(int command) { @@ -1209,21 +2073,39 @@ static void ftrace_startup_enable(int command) ftrace_run_update_code(command); } -static void ftrace_startup(int command) +static int ftrace_startup(struct ftrace_ops *ops, int command) { + int ret; + if (unlikely(ftrace_disabled)) - return; + return -ENODEV; + + ret = __register_ftrace_function(ops); + if (ret) + return ret; ftrace_start_up++; - command |= FTRACE_ENABLE_CALLS; + command |= FTRACE_UPDATE_CALLS; + + ops->flags |= FTRACE_OPS_FL_ENABLED; + + ftrace_hash_rec_enable(ops, 1); ftrace_startup_enable(command); + + return 0; } -static void ftrace_shutdown(int command) +static int ftrace_shutdown(struct ftrace_ops *ops, int command) { + int ret; + if (unlikely(ftrace_disabled)) - return; + return -ENODEV; + + ret = __unregister_ftrace_function(ops); + if (ret) + return ret; ftrace_start_up--; /* @@ -1233,24 +2115,58 @@ static void ftrace_shutdown(int command) */ WARN_ON_ONCE(ftrace_start_up < 0); - if (!ftrace_start_up) - command |= FTRACE_DISABLE_CALLS; + ftrace_hash_rec_disable(ops, 1); + + if (!global_start_up) + ops->flags &= ~FTRACE_OPS_FL_ENABLED; + + command |= FTRACE_UPDATE_CALLS; if (saved_ftrace_func != ftrace_trace_function) { saved_ftrace_func = ftrace_trace_function; command |= FTRACE_UPDATE_TRACE_FUNC; } - if (!command || !ftrace_enabled) - return; + if (!command || !ftrace_enabled) { + /* + * If these are control ops, they still need their + * per_cpu field freed. Since, function tracing is + * not currently active, we can just free them + * without synchronizing all CPUs. + */ + if (ops->flags & FTRACE_OPS_FL_CONTROL) + control_ops_free(ops); + return 0; + } ftrace_run_update_code(command); + + /* + * Dynamic ops may be freed, we must make sure that all + * callers are done before leaving this function. + * The same goes for freeing the per_cpu data of the control + * ops. + * + * Again, normal synchronize_sched() is not good enough. + * We need to do a hard force of sched synchronization. + * This is because we use preempt_disable() to do RCU, but + * the function tracers can be called where RCU is not watching + * (like before user_exit()). We can not rely on the RCU + * infrastructure to do the synchronization, thus we must do it + * ourselves. + */ + if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_CONTROL)) { + schedule_on_each_cpu(ftrace_sync); + + if (ops->flags & FTRACE_OPS_FL_CONTROL) + control_ops_free(ops); + } + + return 0; } static void ftrace_startup_sysctl(void) { - int command = FTRACE_ENABLE_MCOUNT; - if (unlikely(ftrace_disabled)) return; @@ -1258,138 +2174,269 @@ static void ftrace_startup_sysctl(void) saved_ftrace_func = NULL; /* ftrace_start_up is true if we want ftrace running */ if (ftrace_start_up) - command |= FTRACE_ENABLE_CALLS; - - ftrace_run_update_code(command); + ftrace_run_update_code(FTRACE_UPDATE_CALLS); } static void ftrace_shutdown_sysctl(void) { - int command = FTRACE_DISABLE_MCOUNT; - if (unlikely(ftrace_disabled)) return; /* ftrace_start_up is true if ftrace is running */ if (ftrace_start_up) - command |= FTRACE_DISABLE_CALLS; - - ftrace_run_update_code(command); + ftrace_run_update_code(FTRACE_DISABLE_CALLS); } static cycle_t ftrace_update_time; -static unsigned long ftrace_update_cnt; unsigned long ftrace_update_tot_cnt; -static int ftrace_update_code(struct module *mod) +static inline int ops_traces_mod(struct ftrace_ops *ops) +{ + /* + * Filter_hash being empty will default to trace module. + * But notrace hash requires a test of individual module functions. + */ + return ftrace_hash_empty(ops->filter_hash) && + ftrace_hash_empty(ops->notrace_hash); +} + +/* + * Check if the current ops references the record. + * + * If the ops traces all functions, then it was already accounted for. + * If the ops does not trace the current record function, skip it. + * If the ops ignores the function via notrace filter, skip it. + */ +static inline bool +ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec) +{ + /* If ops isn't enabled, ignore it */ + if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) + return 0; + + /* If ops traces all mods, we already accounted for it */ + if (ops_traces_mod(ops)) + return 0; + + /* The function must be in the filter */ + if (!ftrace_hash_empty(ops->filter_hash) && + !ftrace_lookup_ip(ops->filter_hash, rec->ip)) + return 0; + + /* If in notrace hash, we ignore it too */ + if (ftrace_lookup_ip(ops->notrace_hash, rec->ip)) + return 0; + + return 1; +} + +static int referenced_filters(struct dyn_ftrace *rec) +{ + struct ftrace_ops *ops; + int cnt = 0; + + for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) { + if (ops_references_rec(ops, rec)) + cnt++; + } + + return cnt; +} + +static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs) { + struct ftrace_page *pg; struct dyn_ftrace *p; cycle_t start, stop; + unsigned long update_cnt = 0; + unsigned long ref = 0; + bool test = false; + int i; + + /* + * When adding a module, we need to check if tracers are + * currently enabled and if they are set to trace all functions. + * If they are, we need to enable the module functions as well + * as update the reference counts for those function records. + */ + if (mod) { + struct ftrace_ops *ops; + + for (ops = ftrace_ops_list; + ops != &ftrace_list_end; ops = ops->next) { + if (ops->flags & FTRACE_OPS_FL_ENABLED) { + if (ops_traces_mod(ops)) + ref++; + else + test = true; + } + } + } start = ftrace_now(raw_smp_processor_id()); - ftrace_update_cnt = 0; - while (ftrace_new_addrs) { + for (pg = new_pgs; pg; pg = pg->next) { - /* If something went wrong, bail without enabling anything */ - if (unlikely(ftrace_disabled)) - return -1; + for (i = 0; i < pg->index; i++) { + int cnt = ref; - p = ftrace_new_addrs; - ftrace_new_addrs = p->newlist; - p->flags = 0L; + /* If something went wrong, bail without enabling anything */ + if (unlikely(ftrace_disabled)) + return -1; - /* convert record (i.e, patch mcount-call with NOP) */ - if (ftrace_code_disable(mod, p)) { - p->flags |= FTRACE_FL_CONVERTED; - ftrace_update_cnt++; - } else - ftrace_free_rec(p); + p = &pg->records[i]; + if (test) + cnt += referenced_filters(p); + p->flags = cnt; + + /* + * Do the initial record conversion from mcount jump + * to the NOP instructions. + */ + if (!ftrace_code_disable(mod, p)) + break; + + update_cnt++; + + /* + * If the tracing is enabled, go ahead and enable the record. + * + * The reason not to enable the record immediatelly is the + * inherent check of ftrace_make_nop/ftrace_make_call for + * correct previous instructions. Making first the NOP + * conversion puts the module to the correct state, thus + * passing the ftrace_make_call check. + */ + if (ftrace_start_up && cnt) { + int failed = __ftrace_replace_code(p, 1); + if (failed) + ftrace_bug(failed, p->ip); + } + } } stop = ftrace_now(raw_smp_processor_id()); ftrace_update_time = stop - start; - ftrace_update_tot_cnt += ftrace_update_cnt; + ftrace_update_tot_cnt += update_cnt; return 0; } -static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) +static int ftrace_allocate_records(struct ftrace_page *pg, int count) { - struct ftrace_page *pg; + int order; int cnt; - int i; - /* allocate a few pages */ - ftrace_pages_start = (void *)get_zeroed_page(GFP_KERNEL); - if (!ftrace_pages_start) - return -1; + if (WARN_ON(!count)) + return -EINVAL; + + order = get_count_order(DIV_ROUND_UP(count, ENTRIES_PER_PAGE)); /* - * Allocate a few more pages. - * - * TODO: have some parser search vmlinux before - * final linking to find all calls to ftrace. - * Then we can: - * a) know how many pages to allocate. - * and/or - * b) set up the table then. - * - * The dynamic code is still necessary for - * modules. + * We want to fill as much as possible. No more than a page + * may be empty. */ + while ((PAGE_SIZE << order) / ENTRY_SIZE >= count + ENTRIES_PER_PAGE) + order--; - pg = ftrace_pages = ftrace_pages_start; + again: + pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); + + if (!pg->records) { + /* if we can't allocate this size, try something smaller */ + if (!order) + return -ENOMEM; + order >>= 1; + goto again; + } - cnt = num_to_init / ENTRIES_PER_PAGE; - pr_info("ftrace: allocating %ld entries in %d pages\n", - num_to_init, cnt + 1); + cnt = (PAGE_SIZE << order) / ENTRY_SIZE; + pg->size = cnt; - for (i = 0; i < cnt; i++) { - pg->next = (void *)get_zeroed_page(GFP_KERNEL); + if (cnt > count) + cnt = count; - /* If we fail, we'll try later anyway */ - if (!pg->next) + return cnt; +} + +static struct ftrace_page * +ftrace_allocate_pages(unsigned long num_to_init) +{ + struct ftrace_page *start_pg; + struct ftrace_page *pg; + int order; + int cnt; + + if (!num_to_init) + return 0; + + start_pg = pg = kzalloc(sizeof(*pg), GFP_KERNEL); + if (!pg) + return NULL; + + /* + * Try to allocate as much as possible in one continues + * location that fills in all of the space. We want to + * waste as little space as possible. + */ + for (;;) { + cnt = ftrace_allocate_records(pg, num_to_init); + if (cnt < 0) + goto free_pages; + + num_to_init -= cnt; + if (!num_to_init) break; + pg->next = kzalloc(sizeof(*pg), GFP_KERNEL); + if (!pg->next) + goto free_pages; + pg = pg->next; } - return 0; -} + return start_pg; -enum { - FTRACE_ITER_FILTER = (1 << 0), - FTRACE_ITER_CONT = (1 << 1), - FTRACE_ITER_NOTRACE = (1 << 2), - FTRACE_ITER_FAILURES = (1 << 3), - FTRACE_ITER_PRINTALL = (1 << 4), - FTRACE_ITER_HASH = (1 << 5), -}; + free_pages: + while (start_pg) { + order = get_count_order(pg->size / ENTRIES_PER_PAGE); + free_pages((unsigned long)pg->records, order); + start_pg = pg->next; + kfree(pg); + pg = start_pg; + } + pr_info("ftrace: FAILED to allocate memory for functions\n"); + return NULL; +} #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ struct ftrace_iterator { - struct ftrace_page *pg; - int hidx; - int idx; - unsigned flags; - unsigned char buffer[FTRACE_BUFF_MAX+1]; - unsigned buffer_idx; - unsigned filtered; + loff_t pos; + loff_t func_pos; + struct ftrace_page *pg; + struct dyn_ftrace *func; + struct ftrace_func_probe *probe; + struct trace_parser parser; + struct ftrace_hash *hash; + struct ftrace_ops *ops; + int hidx; + int idx; + unsigned flags; }; static void * -t_hash_next(struct seq_file *m, void *v, loff_t *pos) +t_hash_next(struct seq_file *m, loff_t *pos) { struct ftrace_iterator *iter = m->private; - struct hlist_node *hnd = v; + struct hlist_node *hnd = NULL; struct hlist_head *hhd; - WARN_ON(!(iter->flags & FTRACE_ITER_HASH)); - (*pos)++; + iter->pos = *pos; + if (iter->probe) + hnd = &iter->probe->node; retry: if (iter->hidx >= FTRACE_FUNC_HASHSIZE) return NULL; @@ -1412,7 +2459,12 @@ t_hash_next(struct seq_file *m, void *v, loff_t *pos) } } - return hnd; + if (WARN_ON_ONCE(!hnd)) + return NULL; + + iter->probe = hlist_entry(hnd, struct ftrace_func_probe, node); + + return iter; } static void *t_hash_start(struct seq_file *m, loff_t *pos) @@ -1421,36 +2473,40 @@ static void *t_hash_start(struct seq_file *m, loff_t *pos) void *p = NULL; loff_t l; - if (!(iter->flags & FTRACE_ITER_HASH)) - *pos = 0; + if (!(iter->flags & FTRACE_ITER_DO_HASH)) + return NULL; - iter->flags |= FTRACE_ITER_HASH; + if (iter->func_pos > *pos) + return NULL; iter->hidx = 0; - for (l = 0; l <= *pos; ) { - p = t_hash_next(m, p, &l); + for (l = 0; l <= (*pos - iter->func_pos); ) { + p = t_hash_next(m, &l); if (!p) break; } - return p; + if (!p) + return NULL; + + /* Only set this if we have an item */ + iter->flags |= FTRACE_ITER_HASH; + + return iter; } -static int t_hash_show(struct seq_file *m, void *v) +static int +t_hash_show(struct seq_file *m, struct ftrace_iterator *iter) { struct ftrace_func_probe *rec; - struct hlist_node *hnd = v; - char str[KSYM_SYMBOL_LEN]; - rec = hlist_entry(hnd, struct ftrace_func_probe, node); + rec = iter->probe; + if (WARN_ON_ONCE(!rec)) + return -EIO; if (rec->ops->print) return rec->ops->print(m, rec->ip, rec->ops, rec->data); - kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); - seq_printf(m, "%s:", str); - - kallsyms_lookup((unsigned long)rec->ops->func, NULL, NULL, NULL, str); - seq_printf(m, "%s", str); + seq_printf(m, "%ps:%ps", (void *)rec->ip, (void *)rec->ops->func); if (rec->data) seq_printf(m, ":%p", rec->data); @@ -1463,15 +2519,20 @@ static void * t_next(struct seq_file *m, void *v, loff_t *pos) { struct ftrace_iterator *iter = m->private; + struct ftrace_ops *ops = iter->ops; struct dyn_ftrace *rec = NULL; + if (unlikely(ftrace_disabled)) + return NULL; + if (iter->flags & FTRACE_ITER_HASH) - return t_hash_next(m, v, pos); + return t_hash_next(m, pos); (*pos)++; + iter->pos = iter->func_pos = *pos; if (iter->flags & FTRACE_ITER_PRINTALL) - return NULL; + return t_hash_start(m, pos); retry: if (iter->idx >= iter->pg->index) { @@ -1482,49 +2543,76 @@ t_next(struct seq_file *m, void *v, loff_t *pos) } } else { rec = &iter->pg->records[iter->idx++]; - if ((rec->flags & FTRACE_FL_FREE) || - - (!(iter->flags & FTRACE_ITER_FAILURES) && - (rec->flags & FTRACE_FL_FAILED)) || + if (((iter->flags & FTRACE_ITER_FILTER) && + !(ftrace_lookup_ip(ops->filter_hash, rec->ip))) || - ((iter->flags & FTRACE_ITER_FAILURES) && - !(rec->flags & FTRACE_FL_FAILED)) || + ((iter->flags & FTRACE_ITER_NOTRACE) && + !ftrace_lookup_ip(ops->notrace_hash, rec->ip)) || - ((iter->flags & FTRACE_ITER_FILTER) && - !(rec->flags & FTRACE_FL_FILTER)) || + ((iter->flags & FTRACE_ITER_ENABLED) && + !(rec->flags & FTRACE_FL_ENABLED))) { - ((iter->flags & FTRACE_ITER_NOTRACE) && - !(rec->flags & FTRACE_FL_NOTRACE))) { rec = NULL; goto retry; } } - return rec; + if (!rec) + return t_hash_start(m, pos); + + iter->func = rec; + + return iter; +} + +static void reset_iter_read(struct ftrace_iterator *iter) +{ + iter->pos = 0; + iter->func_pos = 0; + iter->flags &= ~(FTRACE_ITER_PRINTALL | FTRACE_ITER_HASH); } static void *t_start(struct seq_file *m, loff_t *pos) { struct ftrace_iterator *iter = m->private; + struct ftrace_ops *ops = iter->ops; void *p = NULL; loff_t l; mutex_lock(&ftrace_lock); + + if (unlikely(ftrace_disabled)) + return NULL; + + /* + * If an lseek was done, then reset and start from beginning. + */ + if (*pos < iter->pos) + reset_iter_read(iter); + /* * For set_ftrace_filter reading, if we have the filter * off, we can short cut and just print out that all * functions are enabled. */ - if (iter->flags & FTRACE_ITER_FILTER && !ftrace_filtered) { + if (iter->flags & FTRACE_ITER_FILTER && + ftrace_hash_empty(ops->filter_hash)) { if (*pos > 0) return t_hash_start(m, pos); iter->flags |= FTRACE_ITER_PRINTALL; + /* reset in case of seek/pread */ + iter->flags &= ~FTRACE_ITER_HASH; return iter; } if (iter->flags & FTRACE_ITER_HASH) return t_hash_start(m, pos); + /* + * Unfortunately, we need to restart at ftrace_pages_start + * every time we let go of the ftrace_mutex. This is because + * those pointers can change without the lock. + */ iter->pg = ftrace_pages_start; iter->idx = 0; for (l = 0; l <= *pos; ) { @@ -1533,10 +2621,10 @@ static void *t_start(struct seq_file *m, loff_t *pos) break; } - if (!p && iter->flags & FTRACE_ITER_FILTER) + if (!p) return t_hash_start(m, pos); - return p; + return iter; } static void t_stop(struct seq_file *m, void *p) @@ -1547,28 +2635,32 @@ static void t_stop(struct seq_file *m, void *p) static int t_show(struct seq_file *m, void *v) { struct ftrace_iterator *iter = m->private; - struct dyn_ftrace *rec = v; - char str[KSYM_SYMBOL_LEN]; + struct dyn_ftrace *rec; if (iter->flags & FTRACE_ITER_HASH) - return t_hash_show(m, v); + return t_hash_show(m, iter); if (iter->flags & FTRACE_ITER_PRINTALL) { seq_printf(m, "#### all functions enabled ####\n"); return 0; } + rec = iter->func; + if (!rec) return 0; - kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); - - seq_printf(m, "%s\n", str); + seq_printf(m, "%ps", (void *)rec->ip); + if (iter->flags & FTRACE_ITER_ENABLED) + seq_printf(m, " (%ld)%s", + rec->flags & ~FTRACE_FL_MASK, + rec->flags & FTRACE_FL_REGS ? " R" : ""); + seq_printf(m, "\n"); return 0; } -static struct seq_operations show_ftrace_seq_ops = { +static const struct seq_operations show_ftrace_seq_ops = { .start = t_start, .next = t_next, .stop = t_stop, @@ -1579,81 +2671,70 @@ static int ftrace_avail_open(struct inode *inode, struct file *file) { struct ftrace_iterator *iter; - int ret; if (unlikely(ftrace_disabled)) return -ENODEV; - iter = kzalloc(sizeof(*iter), GFP_KERNEL); - if (!iter) - return -ENOMEM; - - iter->pg = ftrace_pages_start; - - ret = seq_open(file, &show_ftrace_seq_ops); - if (!ret) { - struct seq_file *m = file->private_data; - - m->private = iter; - } else { - kfree(iter); + iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); + if (iter) { + iter->pg = ftrace_pages_start; + iter->ops = &global_ops; } - return ret; -} - -int ftrace_avail_release(struct inode *inode, struct file *file) -{ - struct seq_file *m = (struct seq_file *)file->private_data; - struct ftrace_iterator *iter = m->private; - - seq_release(inode, file); - kfree(iter); - - return 0; + return iter ? 0 : -ENOMEM; } static int -ftrace_failures_open(struct inode *inode, struct file *file) +ftrace_enabled_open(struct inode *inode, struct file *file) { - int ret; - struct seq_file *m; struct ftrace_iterator *iter; - ret = ftrace_avail_open(inode, file); - if (!ret) { - m = (struct seq_file *)file->private_data; - iter = (struct ftrace_iterator *)m->private; - iter->flags = FTRACE_ITER_FAILURES; + if (unlikely(ftrace_disabled)) + return -ENODEV; + + iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); + if (iter) { + iter->pg = ftrace_pages_start; + iter->flags = FTRACE_ITER_ENABLED; + iter->ops = &global_ops; } - return ret; + return iter ? 0 : -ENOMEM; } - -static void ftrace_filter_reset(int enable) +static void ftrace_filter_reset(struct ftrace_hash *hash) { - struct ftrace_page *pg; - struct dyn_ftrace *rec; - unsigned long type = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; - mutex_lock(&ftrace_lock); - if (enable) - ftrace_filtered = 0; - do_for_each_ftrace_rec(pg, rec) { - if (rec->flags & FTRACE_FL_FAILED) - continue; - rec->flags &= ~type; - } while_for_each_ftrace_rec(); + ftrace_hash_clear(hash); mutex_unlock(&ftrace_lock); } -static int -ftrace_regex_open(struct inode *inode, struct file *file, int enable) +/** + * ftrace_regex_open - initialize function tracer filter files + * @ops: The ftrace_ops that hold the hash filters + * @flag: The type of filter to process + * @inode: The inode, usually passed in to your open routine + * @file: The file, usually passed in to your open routine + * + * ftrace_regex_open() initializes the filter files for the + * @ops. Depending on @flag it may process the filter hash or + * the notrace hash of @ops. With this called from the open + * routine, you can use ftrace_filter_write() for the write + * routine if @flag has FTRACE_ITER_FILTER set, or + * ftrace_notrace_write() if @flag has FTRACE_ITER_NOTRACE set. + * tracing_lseek() should be used as the lseek routine, and + * release must call ftrace_regex_release(). + */ +int +ftrace_regex_open(struct ftrace_ops *ops, int flag, + struct inode *inode, struct file *file) { struct ftrace_iterator *iter; + struct ftrace_hash *hash; int ret = 0; + ftrace_ops_init(ops); + if (unlikely(ftrace_disabled)) return -ENODEV; @@ -1661,25 +2742,53 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable) if (!iter) return -ENOMEM; - mutex_lock(&ftrace_regex_lock); + if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) { + kfree(iter); + return -ENOMEM; + } + + iter->ops = ops; + iter->flags = flag; + + mutex_lock(&ops->regex_lock); + + if (flag & FTRACE_ITER_NOTRACE) + hash = ops->notrace_hash; + else + hash = ops->filter_hash; + + if (file->f_mode & FMODE_WRITE) { + iter->hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash); + if (!iter->hash) { + trace_parser_put(&iter->parser); + kfree(iter); + ret = -ENOMEM; + goto out_unlock; + } + } + if ((file->f_mode & FMODE_WRITE) && - !(file->f_flags & O_APPEND)) - ftrace_filter_reset(enable); + (file->f_flags & O_TRUNC)) + ftrace_filter_reset(iter->hash); if (file->f_mode & FMODE_READ) { iter->pg = ftrace_pages_start; - iter->flags = enable ? FTRACE_ITER_FILTER : - FTRACE_ITER_NOTRACE; ret = seq_open(file, &show_ftrace_seq_ops); if (!ret) { struct seq_file *m = file->private_data; m->private = iter; - } else + } else { + /* Failed */ + free_ftrace_hash(iter->hash); + trace_parser_put(&iter->parser); kfree(iter); + } } else file->private_data = iter; - mutex_unlock(&ftrace_regex_lock); + + out_unlock: + mutex_unlock(&ops->regex_lock); return ret; } @@ -1687,86 +2796,26 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable) static int ftrace_filter_open(struct inode *inode, struct file *file) { - return ftrace_regex_open(inode, file, 1); -} - -static int -ftrace_notrace_open(struct inode *inode, struct file *file) -{ - return ftrace_regex_open(inode, file, 0); -} - -static loff_t -ftrace_regex_lseek(struct file *file, loff_t offset, int origin) -{ - loff_t ret; - - if (file->f_mode & FMODE_READ) - ret = seq_lseek(file, offset, origin); - else - file->f_pos = ret = 1; + struct ftrace_ops *ops = inode->i_private; - return ret; + return ftrace_regex_open(ops, + FTRACE_ITER_FILTER | FTRACE_ITER_DO_HASH, + inode, file); } -enum { - MATCH_FULL, - MATCH_FRONT_ONLY, - MATCH_MIDDLE_ONLY, - MATCH_END_ONLY, -}; - -/* - * (static function - no need for kernel doc) - * - * Pass in a buffer containing a glob and this function will - * set search to point to the search part of the buffer and - * return the type of search it is (see enum above). - * This does modify buff. - * - * Returns enum type. - * search returns the pointer to use for comparison. - * not returns 1 if buff started with a '!' - * 0 otherwise. - */ static int -ftrace_setup_glob(char *buff, int len, char **search, int *not) +ftrace_notrace_open(struct inode *inode, struct file *file) { - int type = MATCH_FULL; - int i; - - if (buff[0] == '!') { - *not = 1; - buff++; - len--; - } else - *not = 0; - - *search = buff; - - for (i = 0; i < len; i++) { - if (buff[i] == '*') { - if (!i) { - *search = buff + 1; - type = MATCH_END_ONLY; - } else { - if (type == MATCH_END_ONLY) - type = MATCH_MIDDLE_ONLY; - else - type = MATCH_FRONT_ONLY; - buff[i] = 0; - break; - } - } - } + struct ftrace_ops *ops = inode->i_private; - return type; + return ftrace_regex_open(ops, FTRACE_ITER_NOTRACE, + inode, file); } static int ftrace_match(char *str, char *regex, int len, int type) { int matched = 0; - char *ptr; + int slen; switch (type) { case MATCH_FULL: @@ -1782,8 +2831,8 @@ static int ftrace_match(char *str, char *regex, int len, int type) matched = 1; break; case MATCH_END_ONLY: - ptr = strstr(str, regex); - if (ptr && (ptr[len] == 0)) + slen = strlen(str); + if (slen >= len && memcmp(str + slen - len, regex, len) == 0) matched = 1; break; } @@ -1792,82 +2841,99 @@ static int ftrace_match(char *str, char *regex, int len, int type) } static int -ftrace_match_record(struct dyn_ftrace *rec, char *regex, int len, int type) +enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int not) +{ + struct ftrace_func_entry *entry; + int ret = 0; + + entry = ftrace_lookup_ip(hash, rec->ip); + if (not) { + /* Do nothing if it doesn't exist */ + if (!entry) + return 0; + + free_hash_entry(hash, entry); + } else { + /* Do nothing if it exists */ + if (entry) + return 0; + + ret = add_hash_entry(hash, rec->ip); + } + return ret; +} + +static int +ftrace_match_record(struct dyn_ftrace *rec, char *mod, + char *regex, int len, int type) { char str[KSYM_SYMBOL_LEN]; + char *modname; + + kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); + + if (mod) { + /* module lookup requires matching the module */ + if (!modname || strcmp(modname, mod)) + return 0; + + /* blank search means to match all funcs in the mod */ + if (!len) + return 1; + } - kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); return ftrace_match(str, regex, len, type); } -static void ftrace_match_records(char *buff, int len, int enable) +static int +match_records(struct ftrace_hash *hash, char *buff, + int len, char *mod, int not) { - unsigned int search_len; + unsigned search_len = 0; struct ftrace_page *pg; struct dyn_ftrace *rec; - unsigned long flag; - char *search; - int type; - int not; - - flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; - type = ftrace_setup_glob(buff, len, &search, ¬); + int type = MATCH_FULL; + char *search = buff; + int found = 0; + int ret; - search_len = strlen(search); + if (len) { + type = filter_parse_regex(buff, len, &search, ¬); + search_len = strlen(search); + } mutex_lock(&ftrace_lock); - do_for_each_ftrace_rec(pg, rec) { - if (rec->flags & FTRACE_FL_FAILED) - continue; + if (unlikely(ftrace_disabled)) + goto out_unlock; - if (ftrace_match_record(rec, search, search_len, type)) { - if (not) - rec->flags &= ~flag; - else - rec->flags |= flag; + do_for_each_ftrace_rec(pg, rec) { + if (ftrace_match_record(rec, mod, search, search_len, type)) { + ret = enter_record(hash, rec, not); + if (ret < 0) { + found = ret; + goto out_unlock; + } + found = 1; } - /* - * Only enable filtering if we have a function that - * is filtered on. - */ - if (enable && (rec->flags & FTRACE_FL_FILTER)) - ftrace_filtered = 1; } while_for_each_ftrace_rec(); + out_unlock: mutex_unlock(&ftrace_lock); + + return found; } static int -ftrace_match_module_record(struct dyn_ftrace *rec, char *mod, - char *regex, int len, int type) +ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) { - char str[KSYM_SYMBOL_LEN]; - char *modname; - - kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); - - if (!modname || strcmp(modname, mod)) - return 0; - - /* blank search means to match all funcs in the mod */ - if (len) - return ftrace_match(str, regex, len, type); - else - return 1; + return match_records(hash, buff, len, NULL, 0); } -static void ftrace_match_module_records(char *buff, char *mod, int enable) +static int +ftrace_match_module_records(struct ftrace_hash *hash, char *buff, char *mod) { - unsigned search_len = 0; - struct ftrace_page *pg; - struct dyn_ftrace *rec; - int type = MATCH_FULL; - char *search = buff; - unsigned long flag; int not = 0; - flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; - /* blank or '*' mean the same */ if (strcmp(buff, "*") == 0) buff[0] = 0; @@ -1878,29 +2944,7 @@ static void ftrace_match_module_records(char *buff, char *mod, int enable) not = 1; } - if (strlen(buff)) { - type = ftrace_setup_glob(buff, strlen(buff), &search, ¬); - search_len = strlen(search); - } - - mutex_lock(&ftrace_lock); - do_for_each_ftrace_rec(pg, rec) { - - if (rec->flags & FTRACE_FL_FAILED) - continue; - - if (ftrace_match_module_record(rec, mod, - search, search_len, type)) { - if (not) - rec->flags &= ~flag; - else - rec->flags |= flag; - } - if (enable && (rec->flags & FTRACE_FL_FILTER)) - ftrace_filtered = 1; - - } while_for_each_ftrace_rec(); - mutex_unlock(&ftrace_lock); + return match_records(hash, buff, strlen(buff), mod, not); } /* @@ -1909,9 +2953,11 @@ static void ftrace_match_module_records(char *buff, char *mod, int enable) */ static int -ftrace_mod_callback(char *func, char *cmd, char *param, int enable) +ftrace_mod_callback(struct ftrace_hash *hash, + char *func, char *cmd, char *param, int enable) { char *mod; + int ret = -EINVAL; /* * cmd == 'mod' because we only registered this func @@ -1923,13 +2969,18 @@ ftrace_mod_callback(char *func, char *cmd, char *param, int enable) /* we must have a module name */ if (!param) - return -EINVAL; + return ret; mod = strsep(¶m, ":"); if (!strlen(mod)) - return -EINVAL; + return ret; + + ret = ftrace_match_module_records(hash, func, mod); + if (!ret) + ret = -EINVAL; + if (ret < 0) + return ret; - ftrace_match_module_records(func, mod, enable); return 0; } @@ -1942,16 +2993,14 @@ static int __init ftrace_mod_cmd_init(void) { return register_ftrace_command(&ftrace_mod_cmd); } -device_initcall(ftrace_mod_cmd_init); +core_initcall(ftrace_mod_cmd_init); -static void -function_trace_probe_call(unsigned long ip, unsigned long parent_ip) +static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct pt_regs *pt_regs) { struct ftrace_func_probe *entry; struct hlist_head *hhd; - struct hlist_node *n; unsigned long key; - int resched; key = hash_long(ip, FTRACE_HASH_BITS); @@ -1965,27 +3014,34 @@ function_trace_probe_call(unsigned long ip, unsigned long parent_ip) * period. This syncs the hash iteration and freeing of items * on the hash. rcu_read_lock is too dangerous here. */ - resched = ftrace_preempt_disable(); - hlist_for_each_entry_rcu(entry, n, hhd, node) { + preempt_disable_notrace(); + hlist_for_each_entry_rcu_notrace(entry, hhd, node) { if (entry->ip == ip) entry->ops->func(ip, parent_ip, &entry->data); } - ftrace_preempt_enable(resched); + preempt_enable_notrace(); } static struct ftrace_ops trace_probe_ops __read_mostly = { .func = function_trace_probe_call, + .flags = FTRACE_OPS_FL_INITIALIZED, + INIT_REGEX_LOCK(trace_probe_ops) }; static int ftrace_probe_registered; static void __enable_ftrace_function_probe(void) { + int ret; int i; - if (ftrace_probe_registered) + if (ftrace_probe_registered) { + /* still need to update the function call sites */ + if (ftrace_enabled) + ftrace_run_update_code(FTRACE_UPDATE_CALLS); return; + } for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { struct hlist_head *hhd = &ftrace_func_hash[i]; @@ -1996,8 +3052,8 @@ static void __enable_ftrace_function_probe(void) if (i == FTRACE_FUNC_HASHSIZE) return; - __register_ftrace_function(&trace_probe_ops); - ftrace_startup(0); + ret = ftrace_startup(&trace_probe_ops, 0); + ftrace_probe_registered = 1; } @@ -2015,49 +3071,59 @@ static void __disable_ftrace_function_probe(void) } /* no more funcs left */ - __unregister_ftrace_function(&trace_probe_ops); - ftrace_shutdown(0); + ftrace_shutdown(&trace_probe_ops, 0); + ftrace_probe_registered = 0; } -static void ftrace_free_entry_rcu(struct rcu_head *rhp) +static void ftrace_free_entry(struct ftrace_func_probe *entry) { - struct ftrace_func_probe *entry = - container_of(rhp, struct ftrace_func_probe, rcu); - if (entry->ops->free) - entry->ops->free(&entry->data); + entry->ops->free(entry->ops, entry->ip, &entry->data); kfree(entry); } - int register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, void *data) { struct ftrace_func_probe *entry; + struct ftrace_hash **orig_hash = &trace_probe_ops.filter_hash; + struct ftrace_hash *hash; struct ftrace_page *pg; struct dyn_ftrace *rec; int type, len, not; unsigned long key; int count = 0; char *search; + int ret; - type = ftrace_setup_glob(glob, strlen(glob), &search, ¬); + type = filter_parse_regex(glob, strlen(glob), &search, ¬); len = strlen(search); /* we do not support '!' for function probes */ if (WARN_ON(not)) return -EINVAL; + mutex_lock(&trace_probe_ops.regex_lock); + + hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); + if (!hash) { + count = -ENOMEM; + goto out; + } + + if (unlikely(ftrace_disabled)) { + count = -ENODEV; + goto out; + } + mutex_lock(&ftrace_lock); - do_for_each_ftrace_rec(pg, rec) { - if (rec->flags & FTRACE_FL_FAILED) - continue; + do_for_each_ftrace_rec(pg, rec) { - if (!ftrace_match_record(rec, search, len, type)) + if (!ftrace_match_record(rec, NULL, search, len, type)) continue; entry = kmalloc(sizeof(*entry), GFP_KERNEL); @@ -2077,14 +3143,21 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, * for each function we find. We call the callback * to give the caller an opportunity to do so. */ - if (ops->callback) { - if (ops->callback(rec->ip, &entry->data) < 0) { + if (ops->init) { + if (ops->init(ops, rec->ip, &entry->data) < 0) { /* caller does not like this func */ kfree(entry); continue; } } + ret = enter_record(hash, rec, 0); + if (ret < 0) { + kfree(entry); + count = ret; + goto out_unlock; + } + entry->ops = ops; entry->ip = rec->ip; @@ -2092,10 +3165,18 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]); } while_for_each_ftrace_rec(); + + ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash); + if (ret < 0) + count = ret; + __enable_ftrace_function_probe(); out_unlock: mutex_unlock(&ftrace_lock); + out: + mutex_unlock(&trace_probe_ops.regex_lock); + free_ftrace_hash(hash); return count; } @@ -2109,19 +3190,24 @@ static void __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, void *data, int flags) { + struct ftrace_func_entry *rec_entry; struct ftrace_func_probe *entry; - struct hlist_node *n, *tmp; + struct ftrace_func_probe *p; + struct ftrace_hash **orig_hash = &trace_probe_ops.filter_hash; + struct list_head free_list; + struct ftrace_hash *hash; + struct hlist_node *tmp; char str[KSYM_SYMBOL_LEN]; int type = MATCH_FULL; int i, len = 0; char *search; - if (glob && (strcmp(glob, "*") || !strlen(glob))) + if (glob && (strcmp(glob, "*") == 0 || !strlen(glob))) glob = NULL; - else { + else if (glob) { int not; - type = ftrace_setup_glob(glob, strlen(glob), &search, ¬); + type = filter_parse_regex(glob, strlen(glob), &search, ¬); len = strlen(search); /* we do not support '!' for function probes */ @@ -2129,11 +3215,19 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, return; } - mutex_lock(&ftrace_lock); + mutex_lock(&trace_probe_ops.regex_lock); + + hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); + if (!hash) + /* Hmm, should report this somehow */ + goto out_unlock; + + INIT_LIST_HEAD(&free_list); + for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { struct hlist_head *hhd = &ftrace_func_hash[i]; - hlist_for_each_entry_safe(entry, n, tmp, hhd, node) { + hlist_for_each_entry_safe(entry, tmp, hhd, node) { /* break up if statements for readability */ if ((flags & PROBE_TEST_FUNC) && entry->ops != ops) @@ -2150,12 +3244,32 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, continue; } - hlist_del(&entry->node); - call_rcu(&entry->rcu, ftrace_free_entry_rcu); + rec_entry = ftrace_lookup_ip(hash, entry->ip); + /* It is possible more than one entry had this ip */ + if (rec_entry) + free_hash_entry(hash, rec_entry); + + hlist_del_rcu(&entry->node); + list_add(&entry->free_list, &free_list); } } + mutex_lock(&ftrace_lock); __disable_ftrace_function_probe(); + /* + * Remove after the disable is called. Otherwise, if the last + * probe is removed, a null hash means *all enabled*. + */ + ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash); + synchronize_sched(); + list_for_each_entry_safe(entry, p, &free_list, free_list) { + list_del(&entry->free_list); + ftrace_free_entry(entry); + } mutex_unlock(&ftrace_lock); + + out_unlock: + mutex_unlock(&trace_probe_ops.regex_lock); + free_ftrace_hash(hash); } void @@ -2180,7 +3294,11 @@ void unregister_ftrace_function_probe_all(char *glob) static LIST_HEAD(ftrace_commands); static DEFINE_MUTEX(ftrace_cmd_mutex); -int register_ftrace_command(struct ftrace_func_command *cmd) +/* + * Currently we only register ftrace commands from __init, so mark this + * __init too. + */ +__init int register_ftrace_command(struct ftrace_func_command *cmd) { struct ftrace_func_command *p; int ret = 0; @@ -2199,7 +3317,11 @@ int register_ftrace_command(struct ftrace_func_command *cmd) return ret; } -int unregister_ftrace_command(struct ftrace_func_command *cmd) +/* + * Currently we only unregister ftrace commands from __init, so mark + * this __init too. + */ +__init int unregister_ftrace_command(struct ftrace_func_command *cmd) { struct ftrace_func_command *p, *n; int ret = -ENODEV; @@ -2218,7 +3340,8 @@ int unregister_ftrace_command(struct ftrace_func_command *cmd) return ret; } -static int ftrace_process_regex(char *buff, int len, int enable) +static int ftrace_process_regex(struct ftrace_hash *hash, + char *buff, int len, int enable) { char *func, *command, *next = buff; struct ftrace_func_command *p; @@ -2227,7 +3350,11 @@ static int ftrace_process_regex(char *buff, int len, int enable) func = strsep(&next, ":"); if (!next) { - ftrace_match_records(func, len, enable); + ret = ftrace_match_records(hash, func, len); + if (!ret) + ret = -EINVAL; + if (ret < 0) + return ret; return 0; } @@ -2238,7 +3365,7 @@ static int ftrace_process_regex(char *buff, int len, int enable) mutex_lock(&ftrace_cmd_mutex); list_for_each_entry(p, &ftrace_commands, list) { if (strcmp(p->name, command) == 0) { - ret = p->func(func, command, next, enable); + ret = p->func(hash, func, command, next, enable); goto out_unlock; } } @@ -2253,116 +3380,164 @@ ftrace_regex_write(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos, int enable) { struct ftrace_iterator *iter; - char ch; - size_t read = 0; - ssize_t ret; + struct trace_parser *parser; + ssize_t ret, read; - if (!cnt || cnt < 0) + if (!cnt) return 0; - mutex_lock(&ftrace_regex_lock); - if (file->f_mode & FMODE_READ) { struct seq_file *m = file->private_data; iter = m->private; } else iter = file->private_data; - if (!*ppos) { - iter->flags &= ~FTRACE_ITER_CONT; - iter->buffer_idx = 0; - } - - ret = get_user(ch, ubuf++); - if (ret) - goto out; - read++; - cnt--; - - if (!(iter->flags & ~FTRACE_ITER_CONT)) { - /* skip white space */ - while (cnt && isspace(ch)) { - ret = get_user(ch, ubuf++); - if (ret) - goto out; - read++; - cnt--; - } + if (unlikely(ftrace_disabled)) + return -ENODEV; - if (isspace(ch)) { - file->f_pos += read; - ret = read; - goto out; - } + /* iter->hash is a local copy, so we don't need regex_lock */ - iter->buffer_idx = 0; - } + parser = &iter->parser; + read = trace_get_user(parser, ubuf, cnt, ppos); - while (cnt && !isspace(ch)) { - if (iter->buffer_idx < FTRACE_BUFF_MAX) - iter->buffer[iter->buffer_idx++] = ch; - else { - ret = -EINVAL; - goto out; - } - ret = get_user(ch, ubuf++); - if (ret) + if (read >= 0 && trace_parser_loaded(parser) && + !trace_parser_cont(parser)) { + ret = ftrace_process_regex(iter->hash, parser->buffer, + parser->idx, enable); + trace_parser_clear(parser); + if (ret < 0) goto out; - read++; - cnt--; } - if (isspace(ch)) { - iter->filtered++; - iter->buffer[iter->buffer_idx] = 0; - ret = ftrace_process_regex(iter->buffer, - iter->buffer_idx, enable); - if (ret) - goto out; - iter->buffer_idx = 0; - } else - iter->flags |= FTRACE_ITER_CONT; - - - file->f_pos += read; - ret = read; out: - mutex_unlock(&ftrace_regex_lock); - return ret; } -static ssize_t +ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos) { return ftrace_regex_write(file, ubuf, cnt, ppos, 1); } -static ssize_t +ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos) { return ftrace_regex_write(file, ubuf, cnt, ppos, 0); } -static void -ftrace_set_regex(unsigned char *buf, int len, int reset, int enable) +static int +ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) +{ + struct ftrace_func_entry *entry; + + if (!ftrace_location(ip)) + return -EINVAL; + + if (remove) { + entry = ftrace_lookup_ip(hash, ip); + if (!entry) + return -ENOENT; + free_hash_entry(hash, entry); + return 0; + } + + return add_hash_entry(hash, ip); +} + +static void ftrace_ops_update_code(struct ftrace_ops *ops) +{ + if (ops->flags & FTRACE_OPS_FL_ENABLED && ftrace_enabled) + ftrace_run_update_code(FTRACE_UPDATE_CALLS); +} + +static int +ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, + unsigned long ip, int remove, int reset, int enable) { + struct ftrace_hash **orig_hash; + struct ftrace_hash *hash; + int ret; + if (unlikely(ftrace_disabled)) - return; + return -ENODEV; + + mutex_lock(&ops->regex_lock); + + if (enable) + orig_hash = &ops->filter_hash; + else + orig_hash = &ops->notrace_hash; + + hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); + if (!hash) { + ret = -ENOMEM; + goto out_regex_unlock; + } - mutex_lock(&ftrace_regex_lock); if (reset) - ftrace_filter_reset(enable); - if (buf) - ftrace_match_records(buf, len, enable); - mutex_unlock(&ftrace_regex_lock); + ftrace_filter_reset(hash); + if (buf && !ftrace_match_records(hash, buf, len)) { + ret = -EINVAL; + goto out_regex_unlock; + } + if (ip) { + ret = ftrace_match_addr(hash, ip, remove); + if (ret < 0) + goto out_regex_unlock; + } + + mutex_lock(&ftrace_lock); + ret = ftrace_hash_move(ops, enable, orig_hash, hash); + if (!ret) + ftrace_ops_update_code(ops); + + mutex_unlock(&ftrace_lock); + + out_regex_unlock: + mutex_unlock(&ops->regex_lock); + + free_ftrace_hash(hash); + return ret; +} + +static int +ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove, + int reset, int enable) +{ + return ftrace_set_hash(ops, 0, 0, ip, remove, reset, enable); +} + +/** + * ftrace_set_filter_ip - set a function to filter on in ftrace by address + * @ops - the ops to set the filter with + * @ip - the address to add to or remove from the filter. + * @remove - non zero to remove the ip from the filter + * @reset - non zero to reset all filters before applying this filter. + * + * Filters denote which functions should be enabled when tracing is enabled + * If @ip is NULL, it failes to update filter. + */ +int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, + int remove, int reset) +{ + ftrace_ops_init(ops); + return ftrace_set_addr(ops, ip, remove, reset, 1); +} +EXPORT_SYMBOL_GPL(ftrace_set_filter_ip); + +static int +ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, + int reset, int enable) +{ + return ftrace_set_hash(ops, buf, len, 0, 0, reset, enable); } /** * ftrace_set_filter - set a function to filter on in ftrace + * @ops - the ops to set the filter with * @buf - the string that holds the function filter text. * @len - the length of the string. * @reset - non zero to reset all filters before applying this filter. @@ -2370,13 +3545,17 @@ ftrace_set_regex(unsigned char *buf, int len, int reset, int enable) * Filters denote which functions should be enabled when tracing is enabled. * If @buf is NULL and reset is set, all functions will be enabled for tracing. */ -void ftrace_set_filter(unsigned char *buf, int len, int reset) +int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, + int len, int reset) { - ftrace_set_regex(buf, len, reset, 1); + ftrace_ops_init(ops); + return ftrace_set_regex(ops, buf, len, reset, 1); } +EXPORT_SYMBOL_GPL(ftrace_set_filter); /** * ftrace_set_notrace - set a function to not trace in ftrace + * @ops - the ops to set the notrace filter with * @buf - the string that holds the function notrace text. * @len - the length of the string. * @reset - non zero to reset all filters before applying this filter. @@ -2385,10 +3564,43 @@ void ftrace_set_filter(unsigned char *buf, int len, int reset) * is enabled. If @buf is NULL and reset is set, all functions will be enabled * for tracing. */ -void ftrace_set_notrace(unsigned char *buf, int len, int reset) +int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, + int len, int reset) { - ftrace_set_regex(buf, len, reset, 0); + ftrace_ops_init(ops); + return ftrace_set_regex(ops, buf, len, reset, 0); } +EXPORT_SYMBOL_GPL(ftrace_set_notrace); +/** + * ftrace_set_global_filter - set a function to filter on with global tracers + * @buf - the string that holds the function filter text. + * @len - the length of the string. + * @reset - non zero to reset all filters before applying this filter. + * + * Filters denote which functions should be enabled when tracing is enabled. + * If @buf is NULL and reset is set, all functions will be enabled for tracing. + */ +void ftrace_set_global_filter(unsigned char *buf, int len, int reset) +{ + ftrace_set_regex(&global_ops, buf, len, reset, 1); +} +EXPORT_SYMBOL_GPL(ftrace_set_global_filter); + +/** + * ftrace_set_global_notrace - set a function to not trace with global tracers + * @buf - the string that holds the function notrace text. + * @len - the length of the string. + * @reset - non zero to reset all filters before applying this filter. + * + * Notrace Filters denote which functions should not be enabled when tracing + * is enabled. If @buf is NULL and reset is set, all functions will be enabled + * for tracing. + */ +void ftrace_set_global_notrace(unsigned char *buf, int len, int reset) +{ + ftrace_set_regex(&global_ops, buf, len, reset, 0); +} +EXPORT_SYMBOL_GPL(ftrace_set_global_notrace); /* * command line interface to allow users to set filters on boot up. @@ -2397,108 +3609,155 @@ void ftrace_set_notrace(unsigned char *buf, int len, int reset) static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; +/* Used by function selftest to not test if filter is set */ +bool ftrace_filter_param __initdata; + static int __init set_ftrace_notrace(char *str) { - strncpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); + ftrace_filter_param = true; + strlcpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); return 1; } __setup("ftrace_notrace=", set_ftrace_notrace); static int __init set_ftrace_filter(char *str) { - strncpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); + ftrace_filter_param = true; + strlcpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); return 1; } __setup("ftrace_filter=", set_ftrace_filter); -static void __init set_ftrace_early_filter(char *buf, int enable) +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; +static int ftrace_set_func(unsigned long *array, int *idx, int size, char *buffer); + +static int __init set_graph_function(char *str) +{ + strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); + return 1; +} +__setup("ftrace_graph_filter=", set_graph_function); + +static void __init set_ftrace_early_graph(char *buf) +{ + int ret; + char *func; + + while (buf) { + func = strsep(&buf, ","); + /* we allow only one expression at a time */ + ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count, + FTRACE_GRAPH_MAX_FUNCS, func); + if (ret) + printk(KERN_DEBUG "ftrace: function %s not " + "traceable\n", func); + } +} +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ + +void __init +ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable) { char *func; + ftrace_ops_init(ops); + while (buf) { func = strsep(&buf, ","); - ftrace_set_regex(func, strlen(func), 0, enable); + ftrace_set_regex(ops, func, strlen(func), 0, enable); } } static void __init set_ftrace_early_filters(void) { if (ftrace_filter_buf[0]) - set_ftrace_early_filter(ftrace_filter_buf, 1); + ftrace_set_early_filter(&global_ops, ftrace_filter_buf, 1); if (ftrace_notrace_buf[0]) - set_ftrace_early_filter(ftrace_notrace_buf, 0); + ftrace_set_early_filter(&global_ops, ftrace_notrace_buf, 0); +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + if (ftrace_graph_buf[0]) + set_ftrace_early_graph(ftrace_graph_buf); +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ } -static int -ftrace_regex_release(struct inode *inode, struct file *file, int enable) +int ftrace_regex_release(struct inode *inode, struct file *file) { struct seq_file *m = (struct seq_file *)file->private_data; struct ftrace_iterator *iter; + struct ftrace_hash **orig_hash; + struct trace_parser *parser; + int filter_hash; + int ret; - mutex_lock(&ftrace_regex_lock); if (file->f_mode & FMODE_READ) { iter = m->private; - seq_release(inode, file); } else iter = file->private_data; - if (iter->buffer_idx) { - iter->filtered++; - iter->buffer[iter->buffer_idx] = 0; - ftrace_match_records(iter->buffer, iter->buffer_idx, enable); + parser = &iter->parser; + if (trace_parser_loaded(parser)) { + parser->buffer[parser->idx] = 0; + ftrace_match_records(iter->hash, parser->buffer, parser->idx); } - mutex_lock(&ftrace_lock); - if (ftrace_start_up && ftrace_enabled) - ftrace_run_update_code(FTRACE_ENABLE_CALLS); - mutex_unlock(&ftrace_lock); + trace_parser_put(parser); - kfree(iter); - mutex_unlock(&ftrace_regex_lock); - return 0; -} + mutex_lock(&iter->ops->regex_lock); -static int -ftrace_filter_release(struct inode *inode, struct file *file) -{ - return ftrace_regex_release(inode, file, 1); -} + if (file->f_mode & FMODE_WRITE) { + filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); -static int -ftrace_notrace_release(struct inode *inode, struct file *file) -{ - return ftrace_regex_release(inode, file, 0); + if (filter_hash) + orig_hash = &iter->ops->filter_hash; + else + orig_hash = &iter->ops->notrace_hash; + + mutex_lock(&ftrace_lock); + ret = ftrace_hash_move(iter->ops, filter_hash, + orig_hash, iter->hash); + if (!ret) + ftrace_ops_update_code(iter->ops); + + mutex_unlock(&ftrace_lock); + } + + mutex_unlock(&iter->ops->regex_lock); + free_ftrace_hash(iter->hash); + kfree(iter); + + return 0; } static const struct file_operations ftrace_avail_fops = { .open = ftrace_avail_open, .read = seq_read, .llseek = seq_lseek, - .release = ftrace_avail_release, + .release = seq_release_private, }; -static const struct file_operations ftrace_failures_fops = { - .open = ftrace_failures_open, +static const struct file_operations ftrace_enabled_fops = { + .open = ftrace_enabled_open, .read = seq_read, .llseek = seq_lseek, - .release = ftrace_avail_release, + .release = seq_release_private, }; static const struct file_operations ftrace_filter_fops = { .open = ftrace_filter_open, .read = seq_read, .write = ftrace_filter_write, - .llseek = ftrace_regex_lseek, - .release = ftrace_filter_release, + .llseek = tracing_lseek, + .release = ftrace_regex_release, }; static const struct file_operations ftrace_notrace_fops = { .open = ftrace_notrace_open, .read = seq_read, .write = ftrace_notrace_write, - .llseek = ftrace_regex_lseek, - .release = ftrace_notrace_release, + .llseek = tracing_lseek, + .release = ftrace_regex_release, }; #ifdef CONFIG_FUNCTION_GRAPH_TRACER @@ -2506,16 +3765,25 @@ static const struct file_operations ftrace_notrace_fops = { static DEFINE_MUTEX(graph_lock); int ftrace_graph_count; +int ftrace_graph_notrace_count; unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; +unsigned long ftrace_graph_notrace_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; + +struct ftrace_graph_data { + unsigned long *table; + size_t size; + int *count; + const struct seq_operations *seq_ops; +}; static void * __g_next(struct seq_file *m, loff_t *pos) { - unsigned long *array = m->private; + struct ftrace_graph_data *fgd = m->private; - if (*pos >= ftrace_graph_count) + if (*pos >= *fgd->count) return NULL; - return &array[*pos]; + return &fgd->table[*pos]; } static void * @@ -2527,10 +3795,12 @@ g_next(struct seq_file *m, void *v, loff_t *pos) static void *g_start(struct seq_file *m, loff_t *pos) { + struct ftrace_graph_data *fgd = m->private; + mutex_lock(&graph_lock); /* Nothing, tell g_show to print all functions are enabled */ - if (!ftrace_graph_count && !*pos) + if (!*fgd->count && !*pos) return (void *)1; return __g_next(m, pos); @@ -2544,7 +3814,6 @@ static void g_stop(struct seq_file *m, void *p) static int g_show(struct seq_file *m, void *v) { unsigned long *ptr = v; - char str[KSYM_SYMBOL_LEN]; if (!ptr) return 0; @@ -2554,14 +3823,12 @@ static int g_show(struct seq_file *m, void *v) return 0; } - kallsyms_lookup(*ptr, NULL, NULL, NULL, str); - - seq_printf(m, "%s\n", str); + seq_printf(m, "%ps\n", (void *)*ptr); return 0; } -static struct seq_operations ftrace_graph_seq_ops = { +static const struct seq_operations ftrace_graph_seq_ops = { .start = g_start, .next = g_next, .stop = g_stop, @@ -2569,202 +3836,329 @@ static struct seq_operations ftrace_graph_seq_ops = { }; static int -ftrace_graph_open(struct inode *inode, struct file *file) +__ftrace_graph_open(struct inode *inode, struct file *file, + struct ftrace_graph_data *fgd) { int ret = 0; - if (unlikely(ftrace_disabled)) - return -ENODEV; - mutex_lock(&graph_lock); if ((file->f_mode & FMODE_WRITE) && - !(file->f_flags & O_APPEND)) { - ftrace_graph_count = 0; - memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); + (file->f_flags & O_TRUNC)) { + *fgd->count = 0; + memset(fgd->table, 0, fgd->size * sizeof(*fgd->table)); } + mutex_unlock(&graph_lock); if (file->f_mode & FMODE_READ) { - ret = seq_open(file, &ftrace_graph_seq_ops); + ret = seq_open(file, fgd->seq_ops); if (!ret) { struct seq_file *m = file->private_data; - m->private = ftrace_graph_funcs; + m->private = fgd; } } else - file->private_data = ftrace_graph_funcs; - mutex_unlock(&graph_lock); + file->private_data = fgd; return ret; } static int -ftrace_set_func(unsigned long *array, int *idx, char *buffer) +ftrace_graph_open(struct inode *inode, struct file *file) +{ + struct ftrace_graph_data *fgd; + + if (unlikely(ftrace_disabled)) + return -ENODEV; + + fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); + if (fgd == NULL) + return -ENOMEM; + + fgd->table = ftrace_graph_funcs; + fgd->size = FTRACE_GRAPH_MAX_FUNCS; + fgd->count = &ftrace_graph_count; + fgd->seq_ops = &ftrace_graph_seq_ops; + + return __ftrace_graph_open(inode, file, fgd); +} + +static int +ftrace_graph_notrace_open(struct inode *inode, struct file *file) +{ + struct ftrace_graph_data *fgd; + + if (unlikely(ftrace_disabled)) + return -ENODEV; + + fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); + if (fgd == NULL) + return -ENOMEM; + + fgd->table = ftrace_graph_notrace_funcs; + fgd->size = FTRACE_GRAPH_MAX_FUNCS; + fgd->count = &ftrace_graph_notrace_count; + fgd->seq_ops = &ftrace_graph_seq_ops; + + return __ftrace_graph_open(inode, file, fgd); +} + +static int +ftrace_graph_release(struct inode *inode, struct file *file) +{ + if (file->f_mode & FMODE_READ) { + struct seq_file *m = file->private_data; + + kfree(m->private); + seq_release(inode, file); + } else { + kfree(file->private_data); + } + + return 0; +} + +static int +ftrace_set_func(unsigned long *array, int *idx, int size, char *buffer) { struct dyn_ftrace *rec; struct ftrace_page *pg; int search_len; - int found = 0; + int fail = 1; int type, not; char *search; bool exists; int i; - if (ftrace_disabled) - return -ENODEV; - /* decode regex */ - type = ftrace_setup_glob(buffer, strlen(buffer), &search, ¬); - if (not) - return -EINVAL; + type = filter_parse_regex(buffer, strlen(buffer), &search, ¬); + if (!not && *idx >= size) + return -EBUSY; search_len = strlen(search); mutex_lock(&ftrace_lock); - do_for_each_ftrace_rec(pg, rec) { - if (*idx >= FTRACE_GRAPH_MAX_FUNCS) - break; + if (unlikely(ftrace_disabled)) { + mutex_unlock(&ftrace_lock); + return -ENODEV; + } - if (rec->flags & (FTRACE_FL_FAILED | FTRACE_FL_FREE)) - continue; + do_for_each_ftrace_rec(pg, rec) { - if (ftrace_match_record(rec, search, search_len, type)) { - /* ensure it is not already in the array */ + if (ftrace_match_record(rec, NULL, search, search_len, type)) { + /* if it is in the array */ exists = false; - for (i = 0; i < *idx; i++) + for (i = 0; i < *idx; i++) { if (array[i] == rec->ip) { exists = true; break; } - if (!exists) { - array[(*idx)++] = rec->ip; - found = 1; + } + + if (!not) { + fail = 0; + if (!exists) { + array[(*idx)++] = rec->ip; + if (*idx >= size) + goto out; + } + } else { + if (exists) { + array[i] = array[--(*idx)]; + array[*idx] = 0; + fail = 0; + } } } } while_for_each_ftrace_rec(); - +out: mutex_unlock(&ftrace_lock); - return found ? 0 : -EINVAL; + if (fail) + return -EINVAL; + + return 0; } static ssize_t ftrace_graph_write(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos) { - unsigned char buffer[FTRACE_BUFF_MAX+1]; - unsigned long *array; - size_t read = 0; - ssize_t ret; - int index = 0; - char ch; + struct trace_parser parser; + ssize_t read, ret = 0; + struct ftrace_graph_data *fgd = file->private_data; - if (!cnt || cnt < 0) + if (!cnt) return 0; - mutex_lock(&graph_lock); - - if (ftrace_graph_count >= FTRACE_GRAPH_MAX_FUNCS) { - ret = -EBUSY; - goto out; - } + if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) + return -ENOMEM; - if (file->f_mode & FMODE_READ) { - struct seq_file *m = file->private_data; - array = m->private; - } else - array = file->private_data; + read = trace_get_user(&parser, ubuf, cnt, ppos); - ret = get_user(ch, ubuf++); - if (ret) - goto out; - read++; - cnt--; + if (read >= 0 && trace_parser_loaded((&parser))) { + parser.buffer[parser.idx] = 0; - /* skip white space */ - while (cnt && isspace(ch)) { - ret = get_user(ch, ubuf++); - if (ret) - goto out; - read++; - cnt--; - } + mutex_lock(&graph_lock); - if (isspace(ch)) { - *ppos += read; - ret = read; - goto out; - } + /* we allow only one expression at a time */ + ret = ftrace_set_func(fgd->table, fgd->count, fgd->size, + parser.buffer); - while (cnt && !isspace(ch)) { - if (index < FTRACE_BUFF_MAX) - buffer[index++] = ch; - else { - ret = -EINVAL; - goto out; - } - ret = get_user(ch, ubuf++); - if (ret) - goto out; - read++; - cnt--; + mutex_unlock(&graph_lock); } - buffer[index] = 0; - - /* we allow only one expression at a time */ - ret = ftrace_set_func(array, &ftrace_graph_count, buffer); - if (ret) - goto out; - file->f_pos += read; + if (!ret) + ret = read; - ret = read; - out: - mutex_unlock(&graph_lock); + trace_parser_put(&parser); return ret; } static const struct file_operations ftrace_graph_fops = { - .open = ftrace_graph_open, - .read = seq_read, - .write = ftrace_graph_write, + .open = ftrace_graph_open, + .read = seq_read, + .write = ftrace_graph_write, + .llseek = tracing_lseek, + .release = ftrace_graph_release, +}; + +static const struct file_operations ftrace_graph_notrace_fops = { + .open = ftrace_graph_notrace_open, + .read = seq_read, + .write = ftrace_graph_write, + .llseek = tracing_lseek, + .release = ftrace_graph_release, }; #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ +void ftrace_create_filter_files(struct ftrace_ops *ops, + struct dentry *parent) +{ + + trace_create_file("set_ftrace_filter", 0644, parent, + ops, &ftrace_filter_fops); + + trace_create_file("set_ftrace_notrace", 0644, parent, + ops, &ftrace_notrace_fops); +} + +/* + * The name "destroy_filter_files" is really a misnomer. Although + * in the future, it may actualy delete the files, but this is + * really intended to make sure the ops passed in are disabled + * and that when this function returns, the caller is free to + * free the ops. + * + * The "destroy" name is only to match the "create" name that this + * should be paired with. + */ +void ftrace_destroy_filter_files(struct ftrace_ops *ops) +{ + mutex_lock(&ftrace_lock); + if (ops->flags & FTRACE_OPS_FL_ENABLED) + ftrace_shutdown(ops, 0); + ops->flags |= FTRACE_OPS_FL_DELETED; + mutex_unlock(&ftrace_lock); +} + static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { trace_create_file("available_filter_functions", 0444, d_tracer, NULL, &ftrace_avail_fops); - trace_create_file("failures", 0444, - d_tracer, NULL, &ftrace_failures_fops); - - trace_create_file("set_ftrace_filter", 0644, d_tracer, - NULL, &ftrace_filter_fops); + trace_create_file("enabled_functions", 0444, + d_tracer, NULL, &ftrace_enabled_fops); - trace_create_file("set_ftrace_notrace", 0644, d_tracer, - NULL, &ftrace_notrace_fops); + ftrace_create_filter_files(&global_ops, d_tracer); #ifdef CONFIG_FUNCTION_GRAPH_TRACER trace_create_file("set_graph_function", 0444, d_tracer, NULL, &ftrace_graph_fops); + trace_create_file("set_graph_notrace", 0444, d_tracer, + NULL, + &ftrace_graph_notrace_fops); #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ return 0; } -static int ftrace_convert_nops(struct module *mod, +static int ftrace_cmp_ips(const void *a, const void *b) +{ + const unsigned long *ipa = a; + const unsigned long *ipb = b; + + if (*ipa > *ipb) + return 1; + if (*ipa < *ipb) + return -1; + return 0; +} + +static void ftrace_swap_ips(void *a, void *b, int size) +{ + unsigned long *ipa = a; + unsigned long *ipb = b; + unsigned long t; + + t = *ipa; + *ipa = *ipb; + *ipb = t; +} + +static int ftrace_process_locs(struct module *mod, unsigned long *start, unsigned long *end) { + struct ftrace_page *start_pg; + struct ftrace_page *pg; + struct dyn_ftrace *rec; + unsigned long count; unsigned long *p; unsigned long addr; - unsigned long flags; + unsigned long flags = 0; /* Shut up gcc */ + int ret = -ENOMEM; + + count = end - start; + + if (!count) + return 0; + + sort(start, count, sizeof(*start), + ftrace_cmp_ips, ftrace_swap_ips); + + start_pg = ftrace_allocate_pages(count); + if (!start_pg) + return -ENOMEM; mutex_lock(&ftrace_lock); + + /* + * Core and each module needs their own pages, as + * modules will free them when they are removed. + * Force a new page to be allocated for modules. + */ + if (!mod) { + WARN_ON(ftrace_pages || ftrace_pages_start); + /* First initialization */ + ftrace_pages = ftrace_pages_start = start_pg; + } else { + if (!ftrace_pages) + goto out; + + if (WARN_ON(ftrace_pages->next)) { + /* Hmm, we have free pages? */ + while (ftrace_pages->next) + ftrace_pages = ftrace_pages->next; + } + + ftrace_pages->next = start_pg; + } + p = start; + pg = start_pg; while (p < end) { addr = ftrace_call_adjust(*p++); /* @@ -2775,40 +4169,87 @@ static int ftrace_convert_nops(struct module *mod, */ if (!addr) continue; - ftrace_record_ip(addr); + + if (pg->index == pg->size) { + /* We should have allocated enough */ + if (WARN_ON(!pg->next)) + break; + pg = pg->next; + } + + rec = &pg->records[pg->index++]; + rec->ip = addr; } - /* disable interrupts to prevent kstop machine */ - local_irq_save(flags); - ftrace_update_code(mod); - local_irq_restore(flags); + /* We should have used all pages */ + WARN_ON(pg->next); + + /* Assign the last page to ftrace_pages */ + ftrace_pages = pg; + + /* + * We only need to disable interrupts on start up + * because we are modifying code that an interrupt + * may execute, and the modification is not atomic. + * But for modules, nothing runs the code we modify + * until we are finished with it, and there's no + * reason to cause large interrupt latencies while we do it. + */ + if (!mod) + local_irq_save(flags); + ftrace_update_code(mod, start_pg); + if (!mod) + local_irq_restore(flags); + ret = 0; + out: mutex_unlock(&ftrace_lock); - return 0; + return ret; } #ifdef CONFIG_MODULES -void ftrace_release(void *start, void *end) + +#define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next) + +void ftrace_release_mod(struct module *mod) { struct dyn_ftrace *rec; + struct ftrace_page **last_pg; struct ftrace_page *pg; - unsigned long s = (unsigned long)start; - unsigned long e = (unsigned long)end; - - if (ftrace_disabled || !start || start == end) - return; + int order; mutex_lock(&ftrace_lock); - do_for_each_ftrace_rec(pg, rec) { - if ((rec->ip >= s) && (rec->ip < e)) { + + if (ftrace_disabled) + goto out_unlock; + + /* + * Each module has its own ftrace_pages, remove + * them from the list. + */ + last_pg = &ftrace_pages_start; + for (pg = ftrace_pages_start; pg; pg = *last_pg) { + rec = &pg->records[0]; + if (within_module_core(rec->ip, mod)) { /* - * rec->ip is changed in ftrace_free_rec() - * It should not between s and e if record was freed. + * As core pages are first, the first + * page should never be a module page. */ - FTRACE_WARN_ON(rec->flags & FTRACE_FL_FREE); - ftrace_free_rec(rec); - } - } while_for_each_ftrace_rec(); + if (WARN_ON(pg == ftrace_pages_start)) + goto out_unlock; + + /* Check if we are deleting the last page */ + if (pg == ftrace_pages) + ftrace_pages = next_to_ftrace_page(last_pg); + + *last_pg = pg->next; + order = get_count_order(pg->size / ENTRIES_PER_PAGE); + free_pages((unsigned long)pg->records, order); + kfree(pg); + } else + last_pg = &pg->next; + } + out_unlock: mutex_unlock(&ftrace_lock); } @@ -2817,76 +4258,70 @@ static void ftrace_init_module(struct module *mod, { if (ftrace_disabled || start == end) return; - ftrace_convert_nops(mod, start, end); + ftrace_process_locs(mod, start, end); +} + +void ftrace_module_init(struct module *mod) +{ + ftrace_init_module(mod, mod->ftrace_callsites, + mod->ftrace_callsites + + mod->num_ftrace_callsites); } -static int ftrace_module_notify(struct notifier_block *self, - unsigned long val, void *data) +static int ftrace_module_notify_exit(struct notifier_block *self, + unsigned long val, void *data) { struct module *mod = data; - switch (val) { - case MODULE_STATE_COMING: - ftrace_init_module(mod, mod->ftrace_callsites, - mod->ftrace_callsites + - mod->num_ftrace_callsites); - break; - case MODULE_STATE_GOING: - ftrace_release(mod->ftrace_callsites, - mod->ftrace_callsites + - mod->num_ftrace_callsites); - break; - } + if (val == MODULE_STATE_GOING) + ftrace_release_mod(mod); return 0; } #else -static int ftrace_module_notify(struct notifier_block *self, - unsigned long val, void *data) +static int ftrace_module_notify_exit(struct notifier_block *self, + unsigned long val, void *data) { return 0; } #endif /* CONFIG_MODULES */ -struct notifier_block ftrace_module_nb = { - .notifier_call = ftrace_module_notify, - .priority = 0, +struct notifier_block ftrace_module_exit_nb = { + .notifier_call = ftrace_module_notify_exit, + .priority = INT_MIN, /* Run after anything that can remove kprobes */ }; -extern unsigned long __start_mcount_loc[]; -extern unsigned long __stop_mcount_loc[]; - void __init ftrace_init(void) { - unsigned long count, addr, flags; + extern unsigned long __start_mcount_loc[]; + extern unsigned long __stop_mcount_loc[]; + unsigned long count, flags; int ret; - /* Keep the ftrace pointer to the stub */ - addr = (unsigned long)ftrace_stub; - local_irq_save(flags); - ftrace_dyn_arch_init(&addr); + ret = ftrace_dyn_arch_init(); local_irq_restore(flags); - - /* ftrace_dyn_arch_init places the return code in addr */ - if (addr) + if (ret) goto failed; count = __stop_mcount_loc - __start_mcount_loc; - - ret = ftrace_dyn_table_alloc(count); - if (ret) + if (!count) { + pr_info("ftrace: No functions to be traced?\n"); goto failed; + } + + pr_info("ftrace: allocating %ld entries in %ld pages\n", + count, count / ENTRIES_PER_PAGE + 1); last_ftrace_enabled = ftrace_enabled = 1; - ret = ftrace_convert_nops(NULL, + ret = ftrace_process_locs(NULL, __start_mcount_loc, __stop_mcount_loc); - ret = register_module_notifier(&ftrace_module_nb); + ret = register_module_notifier(&ftrace_module_exit_nb); if (ret) - pr_warning("Failed to register trace ftrace module notifier\n"); + pr_warning("Failed to register trace ftrace module exit notifier\n"); set_ftrace_early_filters(); @@ -2897,38 +4332,173 @@ void __init ftrace_init(void) #else +static struct ftrace_ops global_ops = { + .func = ftrace_stub, + .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, + INIT_REGEX_LOCK(global_ops) +}; + static int __init ftrace_nodyn_init(void) { ftrace_enabled = 1; return 0; } -device_initcall(ftrace_nodyn_init); +core_initcall(ftrace_nodyn_init); static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } static inline void ftrace_startup_enable(int command) { } /* Keep as macros so we do not need to define the commands */ -# define ftrace_startup(command) do { } while (0) -# define ftrace_shutdown(command) do { } while (0) +# define ftrace_startup(ops, command) \ + ({ \ + int ___ret = __register_ftrace_function(ops); \ + if (!___ret) \ + (ops)->flags |= FTRACE_OPS_FL_ENABLED; \ + ___ret; \ + }) +# define ftrace_shutdown(ops, command) \ + ({ \ + int ___ret = __unregister_ftrace_function(ops); \ + if (!___ret) \ + (ops)->flags &= ~FTRACE_OPS_FL_ENABLED; \ + ___ret; \ + }) + # define ftrace_startup_sysctl() do { } while (0) # define ftrace_shutdown_sysctl() do { } while (0) + +static inline int +ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs) +{ + return 1; +} + #endif /* CONFIG_DYNAMIC_FTRACE */ -static ssize_t -ftrace_pid_read(struct file *file, char __user *ubuf, - size_t cnt, loff_t *ppos) +__init void ftrace_init_global_array_ops(struct trace_array *tr) { - char buf[64]; - int r; + tr->ops = &global_ops; + tr->ops->private = tr; +} - if (ftrace_pid_trace == ftrace_swapper_pid) - r = sprintf(buf, "swapper tasks\n"); - else if (ftrace_pid_trace) - r = sprintf(buf, "%u\n", pid_vnr(ftrace_pid_trace)); - else - r = sprintf(buf, "no pid\n"); +void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func) +{ + /* If we filter on pids, update to use the pid function */ + if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { + if (WARN_ON(tr->ops->func != ftrace_stub)) + printk("ftrace ops had %pS for function\n", + tr->ops->func); + /* Only the top level instance does pid tracing */ + if (!list_empty(&ftrace_pids)) { + set_ftrace_pid_function(func); + func = ftrace_pid_func; + } + } + tr->ops->func = func; + tr->ops->private = tr; +} - return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); +void ftrace_reset_array_ops(struct trace_array *tr) +{ + tr->ops->func = ftrace_stub; +} + +static void +ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct pt_regs *regs) +{ + if (unlikely(trace_recursion_test(TRACE_CONTROL_BIT))) + return; + + /* + * Some of the ops may be dynamically allocated, + * they must be freed after a synchronize_sched(). + */ + preempt_disable_notrace(); + trace_recursion_set(TRACE_CONTROL_BIT); + + /* + * Control funcs (perf) uses RCU. Only trace if + * RCU is currently active. + */ + if (!rcu_is_watching()) + goto out; + + do_for_each_ftrace_op(op, ftrace_control_list) { + if (!(op->flags & FTRACE_OPS_FL_STUB) && + !ftrace_function_local_disabled(op) && + ftrace_ops_test(op, ip, regs)) + op->func(ip, parent_ip, op, regs); + } while_for_each_ftrace_op(op); + out: + trace_recursion_clear(TRACE_CONTROL_BIT); + preempt_enable_notrace(); +} + +static struct ftrace_ops control_ops = { + .func = ftrace_ops_control_func, + .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, + INIT_REGEX_LOCK(control_ops) +}; + +static inline void +__ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *ignored, struct pt_regs *regs) +{ + struct ftrace_ops *op; + int bit; + + if (function_trace_stop) + return; + + bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); + if (bit < 0) + return; + + /* + * Some of the ops may be dynamically allocated, + * they must be freed after a synchronize_sched(). + */ + preempt_disable_notrace(); + do_for_each_ftrace_op(op, ftrace_ops_list) { + if (ftrace_ops_test(op, ip, regs)) { + if (WARN_ON(!op->func)) { + function_trace_stop = 1; + printk("op=%p %pS\n", op, op); + goto out; + } + op->func(ip, parent_ip, op, regs); + } + } while_for_each_ftrace_op(op); +out: + preempt_enable_notrace(); + trace_clear_recursion(bit); +} + +/* + * Some archs only support passing ip and parent_ip. Even though + * the list function ignores the op parameter, we do not want any + * C side effects, where a function is called without the caller + * sending a third parameter. + * Archs are to support both the regs and ftrace_ops at the same time. + * If they support ftrace_ops, it is assumed they support regs. + * If call backs want to use regs, they must either check for regs + * being NULL, or CONFIG_DYNAMIC_FTRACE_WITH_REGS. + * Note, CONFIG_DYNAMIC_FTRACE_WITH_REGS expects a full regs to be saved. + * An architecture can pass partial regs with ftrace_ops and still + * set the ARCH_SUPPORT_FTARCE_OPS. + */ +#if ARCH_SUPPORTS_FTRACE_OPS +static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct pt_regs *regs) +{ + __ftrace_ops_list_func(ip, parent_ip, NULL, regs); +} +#else +static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip) +{ + __ftrace_ops_list_func(ip, parent_ip, NULL, NULL); } +#endif static void clear_ftrace_swapper(void) { @@ -2980,14 +4550,12 @@ static void set_ftrace_pid(struct pid *pid) rcu_read_unlock(); } -static void clear_ftrace_pid_task(struct pid **pid) +static void clear_ftrace_pid_task(struct pid *pid) { - if (*pid == ftrace_swapper_pid) + if (pid == ftrace_swapper_pid) clear_ftrace_swapper(); else - clear_ftrace_pid(*pid); - - *pid = NULL; + clear_ftrace_pid(pid); } static void set_ftrace_pid_task(struct pid *pid) @@ -2998,74 +4566,184 @@ static void set_ftrace_pid_task(struct pid *pid) set_ftrace_pid(pid); } -static ssize_t -ftrace_pid_write(struct file *filp, const char __user *ubuf, - size_t cnt, loff_t *ppos) +static int ftrace_pid_add(int p) { struct pid *pid; - char buf[64]; - long val; - int ret; + struct ftrace_pid *fpid; + int ret = -EINVAL; - if (cnt >= sizeof(buf)) - return -EINVAL; + mutex_lock(&ftrace_lock); - if (copy_from_user(&buf, ubuf, cnt)) - return -EFAULT; + if (!p) + pid = ftrace_swapper_pid; + else + pid = find_get_pid(p); - buf[cnt] = 0; + if (!pid) + goto out; - ret = strict_strtol(buf, 10, &val); - if (ret < 0) - return ret; + ret = 0; - mutex_lock(&ftrace_lock); - if (val < 0) { - /* disable pid tracing */ - if (!ftrace_pid_trace) - goto out; + list_for_each_entry(fpid, &ftrace_pids, list) + if (fpid->pid == pid) + goto out_put; - clear_ftrace_pid_task(&ftrace_pid_trace); + ret = -ENOMEM; - } else { - /* swapper task is special */ - if (!val) { - pid = ftrace_swapper_pid; - if (pid == ftrace_pid_trace) - goto out; - } else { - pid = find_get_pid(val); + fpid = kmalloc(sizeof(*fpid), GFP_KERNEL); + if (!fpid) + goto out_put; - if (pid == ftrace_pid_trace) { - put_pid(pid); - goto out; - } - } + list_add(&fpid->list, &ftrace_pids); + fpid->pid = pid; - if (ftrace_pid_trace) - clear_ftrace_pid_task(&ftrace_pid_trace); + set_ftrace_pid_task(pid); - if (!pid) - goto out; + ftrace_update_pid_func(); + ftrace_startup_enable(0); + + mutex_unlock(&ftrace_lock); + return 0; + +out_put: + if (pid != ftrace_swapper_pid) + put_pid(pid); + +out: + mutex_unlock(&ftrace_lock); + return ret; +} + +static void ftrace_pid_reset(void) +{ + struct ftrace_pid *fpid, *safe; - ftrace_pid_trace = pid; + mutex_lock(&ftrace_lock); + list_for_each_entry_safe(fpid, safe, &ftrace_pids, list) { + struct pid *pid = fpid->pid; + + clear_ftrace_pid_task(pid); - set_ftrace_pid_task(ftrace_pid_trace); + list_del(&fpid->list); + kfree(fpid); } - /* update the function call */ ftrace_update_pid_func(); ftrace_startup_enable(0); - out: mutex_unlock(&ftrace_lock); +} - return cnt; +static void *fpid_start(struct seq_file *m, loff_t *pos) +{ + mutex_lock(&ftrace_lock); + + if (list_empty(&ftrace_pids) && (!*pos)) + return (void *) 1; + + return seq_list_start(&ftrace_pids, *pos); +} + +static void *fpid_next(struct seq_file *m, void *v, loff_t *pos) +{ + if (v == (void *)1) + return NULL; + + return seq_list_next(v, &ftrace_pids, pos); +} + +static void fpid_stop(struct seq_file *m, void *p) +{ + mutex_unlock(&ftrace_lock); +} + +static int fpid_show(struct seq_file *m, void *v) +{ + const struct ftrace_pid *fpid = list_entry(v, struct ftrace_pid, list); + + if (v == (void *)1) { + seq_printf(m, "no pid\n"); + return 0; + } + + if (fpid->pid == ftrace_swapper_pid) + seq_printf(m, "swapper tasks\n"); + else + seq_printf(m, "%u\n", pid_vnr(fpid->pid)); + + return 0; +} + +static const struct seq_operations ftrace_pid_sops = { + .start = fpid_start, + .next = fpid_next, + .stop = fpid_stop, + .show = fpid_show, +}; + +static int +ftrace_pid_open(struct inode *inode, struct file *file) +{ + int ret = 0; + + if ((file->f_mode & FMODE_WRITE) && + (file->f_flags & O_TRUNC)) + ftrace_pid_reset(); + + if (file->f_mode & FMODE_READ) + ret = seq_open(file, &ftrace_pid_sops); + + return ret; +} + +static ssize_t +ftrace_pid_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + char buf[64], *tmp; + long val; + int ret; + + if (cnt >= sizeof(buf)) + return -EINVAL; + + if (copy_from_user(&buf, ubuf, cnt)) + return -EFAULT; + + buf[cnt] = 0; + + /* + * Allow "echo > set_ftrace_pid" or "echo -n '' > set_ftrace_pid" + * to clean the filter quietly. + */ + tmp = strstrip(buf); + if (strlen(tmp) == 0) + return 1; + + ret = kstrtol(tmp, 10, &val); + if (ret < 0) + return ret; + + ret = ftrace_pid_add(val); + + return ret ? ret : cnt; +} + +static int +ftrace_pid_release(struct inode *inode, struct file *file) +{ + if (file->f_mode & FMODE_READ) + seq_release(inode, file); + + return 0; } static const struct file_operations ftrace_pid_fops = { - .read = ftrace_pid_read, - .write = ftrace_pid_write, + .open = ftrace_pid_open, + .write = ftrace_pid_write, + .read = seq_read, + .llseek = tracing_lseek, + .release = ftrace_pid_release, }; static __init int ftrace_init_debugfs(void) @@ -3102,6 +4780,14 @@ void ftrace_kill(void) } /** + * Test if ftrace is dead or not. + */ +int ftrace_is_dead(void) +{ + return ftrace_disabled; +} + +/** * register_ftrace_function - register a function for profiling * @ops - ops structure that holds the function for profiling. * @@ -3114,19 +4800,19 @@ void ftrace_kill(void) */ int register_ftrace_function(struct ftrace_ops *ops) { - int ret; + int ret = -1; - if (unlikely(ftrace_disabled)) - return -1; + ftrace_ops_init(ops); mutex_lock(&ftrace_lock); - ret = __register_ftrace_function(ops); - ftrace_startup(0); + ret = ftrace_startup(ops, 0); mutex_unlock(&ftrace_lock); + return ret; } +EXPORT_SYMBOL_GPL(register_ftrace_function); /** * unregister_ftrace_function - unregister a function for profiling. @@ -3139,43 +4825,39 @@ int unregister_ftrace_function(struct ftrace_ops *ops) int ret; mutex_lock(&ftrace_lock); - ret = __unregister_ftrace_function(ops); - ftrace_shutdown(0); + ret = ftrace_shutdown(ops, 0); mutex_unlock(&ftrace_lock); return ret; } +EXPORT_SYMBOL_GPL(unregister_ftrace_function); int ftrace_enable_sysctl(struct ctl_table *table, int write, - struct file *file, void __user *buffer, size_t *lenp, + void __user *buffer, size_t *lenp, loff_t *ppos) { - int ret; - - if (unlikely(ftrace_disabled)) - return -ENODEV; + int ret = -ENODEV; mutex_lock(&ftrace_lock); - ret = proc_dointvec(table, write, file, buffer, lenp, ppos); + if (unlikely(ftrace_disabled)) + goto out; + + ret = proc_dointvec(table, write, buffer, lenp, ppos); - if (ret || !write || (last_ftrace_enabled == ftrace_enabled)) + if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) goto out; - last_ftrace_enabled = ftrace_enabled; + last_ftrace_enabled = !!ftrace_enabled; if (ftrace_enabled) { ftrace_startup_sysctl(); /* we are starting ftrace again */ - if (ftrace_list != &ftrace_list_end) { - if (ftrace_list->next == &ftrace_list_end) - ftrace_trace_function = ftrace_list->func; - else - ftrace_trace_function = ftrace_list_func; - } + if (ftrace_ops_list != &ftrace_list_end) + update_ftrace_function(); } else { /* stopping ftrace calls (just send to ftrace_stub) */ @@ -3192,7 +4874,6 @@ ftrace_enable_sysctl(struct ctl_table *table, int write, #ifdef CONFIG_FUNCTION_GRAPH_TRACER static int ftrace_graph_active; -static struct notifier_block ftrace_suspend_notifier; int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) { @@ -3203,6 +4884,7 @@ int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) trace_func_graph_ret_t ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; +static trace_func_graph_ent_t __ftrace_graph_entry = ftrace_graph_entry_stub; /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) @@ -3251,8 +4933,8 @@ free: } static void -ftrace_graph_probe_sched_switch(struct rq *__rq, struct task_struct *prev, - struct task_struct *next) +ftrace_graph_probe_sched_switch(void *ignore, + struct task_struct *prev, struct task_struct *next) { unsigned long long timestamp; int index; @@ -3298,7 +4980,7 @@ static int start_graph_tracing(void) /* The cpu_boot init_task->ret_stack will never be freed */ for_each_online_cpu(cpu) { if (!idle_task(cpu)->ret_stack) - ftrace_graph_init_task(idle_task(cpu)); + ftrace_graph_init_idle_task(idle_task(cpu), cpu); } do { @@ -3306,7 +4988,7 @@ static int start_graph_tracing(void) } while (ret == -EAGAIN); if (!ret) { - ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch); + ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); if (ret) pr_info("ftrace_graph: Couldn't activate tracepoint" " probe to kernel_sched_switch\n"); @@ -3337,6 +5019,34 @@ ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, return NOTIFY_DONE; } +static int ftrace_graph_entry_test(struct ftrace_graph_ent *trace) +{ + if (!ftrace_ops_test(&global_ops, trace->func, NULL)) + return 0; + return __ftrace_graph_entry(trace); +} + +/* + * The function graph tracer should only trace the functions defined + * by set_ftrace_filter and set_ftrace_notrace. If another function + * tracer ops is registered, the graph tracer requires testing the + * function against the global ops, and not just trace any function + * that any ftrace_ops registered. + */ +static void update_function_graph_func(void) +{ + if (ftrace_ops_list == &ftrace_list_end || + (ftrace_ops_list == &global_ops && + global_ops.next == &ftrace_list_end)) + ftrace_graph_entry = __ftrace_graph_entry; + else + ftrace_graph_entry = ftrace_graph_entry_test; +} + +static struct notifier_block ftrace_suspend_notifier = { + .notifier_call = ftrace_suspend_notifier_call, +}; + int register_ftrace_graph(trace_func_graph_ret_t retfunc, trace_func_graph_ent_t entryfunc) { @@ -3350,7 +5060,6 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc, goto out; } - ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call; register_pm_notifier(&ftrace_suspend_notifier); ftrace_graph_active++; @@ -3361,9 +5070,21 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc, } ftrace_graph_return = retfunc; - ftrace_graph_entry = entryfunc; - ftrace_startup(FTRACE_START_FUNC_RET); + /* + * Update the indirect function to the entryfunc, and the + * function that gets called to the entry_test first. Then + * call the update fgraph entry function to determine if + * the entryfunc should be called directly or not. + */ + __ftrace_graph_entry = entryfunc; + ftrace_graph_entry = ftrace_graph_entry_test; + update_function_graph_func(); + + /* Function graph doesn't use the .func field of global_ops */ + global_ops.flags |= FTRACE_OPS_FL_STUB; + + ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET); out: mutex_unlock(&ftrace_lock); @@ -3378,21 +5099,67 @@ void unregister_ftrace_graph(void) goto out; ftrace_graph_active--; - unregister_trace_sched_switch(ftrace_graph_probe_sched_switch); ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; ftrace_graph_entry = ftrace_graph_entry_stub; - ftrace_shutdown(FTRACE_STOP_FUNC_RET); + __ftrace_graph_entry = ftrace_graph_entry_stub; + ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET); + global_ops.flags &= ~FTRACE_OPS_FL_STUB; unregister_pm_notifier(&ftrace_suspend_notifier); + unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); out: mutex_unlock(&ftrace_lock); } +static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack); + +static void +graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack) +{ + atomic_set(&t->tracing_graph_pause, 0); + atomic_set(&t->trace_overrun, 0); + t->ftrace_timestamp = 0; + /* make curr_ret_stack visible before we add the ret_stack */ + smp_wmb(); + t->ret_stack = ret_stack; +} + +/* + * Allocate a return stack for the idle task. May be the first + * time through, or it may be done by CPU hotplug online. + */ +void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) +{ + t->curr_ret_stack = -1; + /* + * The idle task has no parent, it either has its own + * stack or no stack at all. + */ + if (t->ret_stack) + WARN_ON(t->ret_stack != per_cpu(idle_ret_stack, cpu)); + + if (ftrace_graph_active) { + struct ftrace_ret_stack *ret_stack; + + ret_stack = per_cpu(idle_ret_stack, cpu); + if (!ret_stack) { + ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH + * sizeof(struct ftrace_ret_stack), + GFP_KERNEL); + if (!ret_stack) + return; + per_cpu(idle_ret_stack, cpu) = ret_stack; + } + graph_init_task(t, ret_stack); + } +} + /* Allocate a return stack for newly created task */ void ftrace_graph_init_task(struct task_struct *t) { /* Make sure we do not use the parent ret_stack */ t->ret_stack = NULL; + t->curr_ret_stack = -1; if (ftrace_graph_active) { struct ftrace_ret_stack *ret_stack; @@ -3402,13 +5169,7 @@ void ftrace_graph_init_task(struct task_struct *t) GFP_KERNEL); if (!ret_stack) return; - t->curr_ret_stack = -1; - atomic_set(&t->tracing_graph_pause, 0); - atomic_set(&t->trace_overrun, 0); - t->ftrace_timestamp = 0; - /* make curr_ret_stack visable before we add the ret_stack */ - smp_wmb(); - t->ret_stack = ret_stack; + graph_init_task(t, ret_stack); } } @@ -3428,4 +5189,3 @@ void ftrace_graph_stop(void) ftrace_stop(); } #endif - diff --git a/kernel/trace/kmemtrace.c b/kernel/trace/kmemtrace.c deleted file mode 100644 index 1edaa9516e8..00000000000 --- a/kernel/trace/kmemtrace.c +++ /dev/null @@ -1,468 +0,0 @@ -/* - * Memory allocator tracing - * - * Copyright (C) 2008 Eduard - Gabriel Munteanu - * Copyright (C) 2008 Pekka Enberg <penberg@cs.helsinki.fi> - * Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com> - */ - -#include <linux/tracepoint.h> -#include <linux/seq_file.h> -#include <linux/debugfs.h> -#include <linux/dcache.h> -#include <linux/fs.h> - -#include <linux/kmemtrace.h> - -#include "trace_output.h" -#include "trace.h" - -/* Select an alternative, minimalistic output than the original one */ -#define TRACE_KMEM_OPT_MINIMAL 0x1 - -static struct tracer_opt kmem_opts[] = { - /* Default disable the minimalistic output */ - { TRACER_OPT(kmem_minimalistic, TRACE_KMEM_OPT_MINIMAL) }, - { } -}; - -static struct tracer_flags kmem_tracer_flags = { - .val = 0, - .opts = kmem_opts -}; - -static struct trace_array *kmemtrace_array; - -/* Trace allocations */ -static inline void kmemtrace_alloc(enum kmemtrace_type_id type_id, - unsigned long call_site, - const void *ptr, - size_t bytes_req, - size_t bytes_alloc, - gfp_t gfp_flags, - int node) -{ - struct ftrace_event_call *call = &event_kmem_alloc; - struct trace_array *tr = kmemtrace_array; - struct kmemtrace_alloc_entry *entry; - struct ring_buffer_event *event; - - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry)); - if (!event) - return; - - entry = ring_buffer_event_data(event); - tracing_generic_entry_update(&entry->ent, 0, 0); - - entry->ent.type = TRACE_KMEM_ALLOC; - entry->type_id = type_id; - entry->call_site = call_site; - entry->ptr = ptr; - entry->bytes_req = bytes_req; - entry->bytes_alloc = bytes_alloc; - entry->gfp_flags = gfp_flags; - entry->node = node; - - if (!filter_check_discard(call, entry, tr->buffer, event)) - ring_buffer_unlock_commit(tr->buffer, event); - - trace_wake_up(); -} - -static inline void kmemtrace_free(enum kmemtrace_type_id type_id, - unsigned long call_site, - const void *ptr) -{ - struct ftrace_event_call *call = &event_kmem_free; - struct trace_array *tr = kmemtrace_array; - struct kmemtrace_free_entry *entry; - struct ring_buffer_event *event; - - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry)); - if (!event) - return; - entry = ring_buffer_event_data(event); - tracing_generic_entry_update(&entry->ent, 0, 0); - - entry->ent.type = TRACE_KMEM_FREE; - entry->type_id = type_id; - entry->call_site = call_site; - entry->ptr = ptr; - - if (!filter_check_discard(call, entry, tr->buffer, event)) - ring_buffer_unlock_commit(tr->buffer, event); - - trace_wake_up(); -} - -static void kmemtrace_kmalloc(unsigned long call_site, - const void *ptr, - size_t bytes_req, - size_t bytes_alloc, - gfp_t gfp_flags) -{ - kmemtrace_alloc(KMEMTRACE_TYPE_KMALLOC, call_site, ptr, - bytes_req, bytes_alloc, gfp_flags, -1); -} - -static void kmemtrace_kmem_cache_alloc(unsigned long call_site, - const void *ptr, - size_t bytes_req, - size_t bytes_alloc, - gfp_t gfp_flags) -{ - kmemtrace_alloc(KMEMTRACE_TYPE_CACHE, call_site, ptr, - bytes_req, bytes_alloc, gfp_flags, -1); -} - -static void kmemtrace_kmalloc_node(unsigned long call_site, - const void *ptr, - size_t bytes_req, - size_t bytes_alloc, - gfp_t gfp_flags, - int node) -{ - kmemtrace_alloc(KMEMTRACE_TYPE_KMALLOC, call_site, ptr, - bytes_req, bytes_alloc, gfp_flags, node); -} - -static void kmemtrace_kmem_cache_alloc_node(unsigned long call_site, - const void *ptr, - size_t bytes_req, - size_t bytes_alloc, - gfp_t gfp_flags, - int node) -{ - kmemtrace_alloc(KMEMTRACE_TYPE_CACHE, call_site, ptr, - bytes_req, bytes_alloc, gfp_flags, node); -} - -static void kmemtrace_kfree(unsigned long call_site, const void *ptr) -{ - kmemtrace_free(KMEMTRACE_TYPE_KMALLOC, call_site, ptr); -} - -static void kmemtrace_kmem_cache_free(unsigned long call_site, const void *ptr) -{ - kmemtrace_free(KMEMTRACE_TYPE_CACHE, call_site, ptr); -} - -static int kmemtrace_start_probes(void) -{ - int err; - - err = register_trace_kmalloc(kmemtrace_kmalloc); - if (err) - return err; - err = register_trace_kmem_cache_alloc(kmemtrace_kmem_cache_alloc); - if (err) - return err; - err = register_trace_kmalloc_node(kmemtrace_kmalloc_node); - if (err) - return err; - err = register_trace_kmem_cache_alloc_node(kmemtrace_kmem_cache_alloc_node); - if (err) - return err; - err = register_trace_kfree(kmemtrace_kfree); - if (err) - return err; - err = register_trace_kmem_cache_free(kmemtrace_kmem_cache_free); - - return err; -} - -static void kmemtrace_stop_probes(void) -{ - unregister_trace_kmalloc(kmemtrace_kmalloc); - unregister_trace_kmem_cache_alloc(kmemtrace_kmem_cache_alloc); - unregister_trace_kmalloc_node(kmemtrace_kmalloc_node); - unregister_trace_kmem_cache_alloc_node(kmemtrace_kmem_cache_alloc_node); - unregister_trace_kfree(kmemtrace_kfree); - unregister_trace_kmem_cache_free(kmemtrace_kmem_cache_free); -} - -static int kmem_trace_init(struct trace_array *tr) -{ - int cpu; - kmemtrace_array = tr; - - for_each_cpu(cpu, cpu_possible_mask) - tracing_reset(tr, cpu); - - kmemtrace_start_probes(); - - return 0; -} - -static void kmem_trace_reset(struct trace_array *tr) -{ - kmemtrace_stop_probes(); -} - -static void kmemtrace_headers(struct seq_file *s) -{ - /* Don't need headers for the original kmemtrace output */ - if (!(kmem_tracer_flags.val & TRACE_KMEM_OPT_MINIMAL)) - return; - - seq_printf(s, "#\n"); - seq_printf(s, "# ALLOC TYPE REQ GIVEN FLAGS " - " POINTER NODE CALLER\n"); - seq_printf(s, "# FREE | | | | " - " | | | |\n"); - seq_printf(s, "# |\n\n"); -} - -/* - * The following functions give the original output from kmemtrace, - * plus the origin CPU, since reordering occurs in-kernel now. - */ - -#define KMEMTRACE_USER_ALLOC 0 -#define KMEMTRACE_USER_FREE 1 - -struct kmemtrace_user_event { - u8 event_id; - u8 type_id; - u16 event_size; - u32 cpu; - u64 timestamp; - unsigned long call_site; - unsigned long ptr; -}; - -struct kmemtrace_user_event_alloc { - size_t bytes_req; - size_t bytes_alloc; - unsigned gfp_flags; - int node; -}; - -static enum print_line_t -kmemtrace_print_alloc_user(struct trace_iterator *iter, - struct kmemtrace_alloc_entry *entry) -{ - struct kmemtrace_user_event_alloc *ev_alloc; - struct trace_seq *s = &iter->seq; - struct kmemtrace_user_event *ev; - - ev = trace_seq_reserve(s, sizeof(*ev)); - if (!ev) - return TRACE_TYPE_PARTIAL_LINE; - - ev->event_id = KMEMTRACE_USER_ALLOC; - ev->type_id = entry->type_id; - ev->event_size = sizeof(*ev) + sizeof(*ev_alloc); - ev->cpu = iter->cpu; - ev->timestamp = iter->ts; - ev->call_site = entry->call_site; - ev->ptr = (unsigned long)entry->ptr; - - ev_alloc = trace_seq_reserve(s, sizeof(*ev_alloc)); - if (!ev_alloc) - return TRACE_TYPE_PARTIAL_LINE; - - ev_alloc->bytes_req = entry->bytes_req; - ev_alloc->bytes_alloc = entry->bytes_alloc; - ev_alloc->gfp_flags = entry->gfp_flags; - ev_alloc->node = entry->node; - - return TRACE_TYPE_HANDLED; -} - -static enum print_line_t -kmemtrace_print_free_user(struct trace_iterator *iter, - struct kmemtrace_free_entry *entry) -{ - struct trace_seq *s = &iter->seq; - struct kmemtrace_user_event *ev; - - ev = trace_seq_reserve(s, sizeof(*ev)); - if (!ev) - return TRACE_TYPE_PARTIAL_LINE; - - ev->event_id = KMEMTRACE_USER_FREE; - ev->type_id = entry->type_id; - ev->event_size = sizeof(*ev); - ev->cpu = iter->cpu; - ev->timestamp = iter->ts; - ev->call_site = entry->call_site; - ev->ptr = (unsigned long)entry->ptr; - - return TRACE_TYPE_HANDLED; -} - -/* The two other following provide a more minimalistic output */ -static enum print_line_t -kmemtrace_print_alloc_compress(struct trace_iterator *iter, - struct kmemtrace_alloc_entry *entry) -{ - struct trace_seq *s = &iter->seq; - int ret; - - /* Alloc entry */ - ret = trace_seq_printf(s, " + "); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - /* Type */ - switch (entry->type_id) { - case KMEMTRACE_TYPE_KMALLOC: - ret = trace_seq_printf(s, "K "); - break; - case KMEMTRACE_TYPE_CACHE: - ret = trace_seq_printf(s, "C "); - break; - case KMEMTRACE_TYPE_PAGES: - ret = trace_seq_printf(s, "P "); - break; - default: - ret = trace_seq_printf(s, "? "); - } - - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - /* Requested */ - ret = trace_seq_printf(s, "%4zu ", entry->bytes_req); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - /* Allocated */ - ret = trace_seq_printf(s, "%4zu ", entry->bytes_alloc); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - /* Flags - * TODO: would be better to see the name of the GFP flag names - */ - ret = trace_seq_printf(s, "%08x ", entry->gfp_flags); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - /* Pointer to allocated */ - ret = trace_seq_printf(s, "0x%tx ", (ptrdiff_t)entry->ptr); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - /* Node */ - ret = trace_seq_printf(s, "%4d ", entry->node); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - /* Call site */ - ret = seq_print_ip_sym(s, entry->call_site, 0); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - if (!trace_seq_printf(s, "\n")) - return TRACE_TYPE_PARTIAL_LINE; - - return TRACE_TYPE_HANDLED; -} - -static enum print_line_t -kmemtrace_print_free_compress(struct trace_iterator *iter, - struct kmemtrace_free_entry *entry) -{ - struct trace_seq *s = &iter->seq; - int ret; - - /* Free entry */ - ret = trace_seq_printf(s, " - "); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - /* Type */ - switch (entry->type_id) { - case KMEMTRACE_TYPE_KMALLOC: - ret = trace_seq_printf(s, "K "); - break; - case KMEMTRACE_TYPE_CACHE: - ret = trace_seq_printf(s, "C "); - break; - case KMEMTRACE_TYPE_PAGES: - ret = trace_seq_printf(s, "P "); - break; - default: - ret = trace_seq_printf(s, "? "); - } - - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - /* Skip requested/allocated/flags */ - ret = trace_seq_printf(s, " "); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - /* Pointer to allocated */ - ret = trace_seq_printf(s, "0x%tx ", (ptrdiff_t)entry->ptr); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - /* Skip node */ - ret = trace_seq_printf(s, " "); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - /* Call site */ - ret = seq_print_ip_sym(s, entry->call_site, 0); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - if (!trace_seq_printf(s, "\n")) - return TRACE_TYPE_PARTIAL_LINE; - - return TRACE_TYPE_HANDLED; -} - -static enum print_line_t kmemtrace_print_line(struct trace_iterator *iter) -{ - struct trace_entry *entry = iter->ent; - - switch (entry->type) { - case TRACE_KMEM_ALLOC: { - struct kmemtrace_alloc_entry *field; - - trace_assign_type(field, entry); - if (kmem_tracer_flags.val & TRACE_KMEM_OPT_MINIMAL) - return kmemtrace_print_alloc_compress(iter, field); - else - return kmemtrace_print_alloc_user(iter, field); - } - - case TRACE_KMEM_FREE: { - struct kmemtrace_free_entry *field; - - trace_assign_type(field, entry); - if (kmem_tracer_flags.val & TRACE_KMEM_OPT_MINIMAL) - return kmemtrace_print_free_compress(iter, field); - else - return kmemtrace_print_free_user(iter, field); - } - - default: - return TRACE_TYPE_UNHANDLED; - } -} - -static struct tracer kmem_tracer __read_mostly = { - .name = "kmemtrace", - .init = kmem_trace_init, - .reset = kmem_trace_reset, - .print_line = kmemtrace_print_line, - .print_header = kmemtrace_headers, - .flags = &kmem_tracer_flags -}; - -void kmemtrace_init(void) -{ - /* earliest opportunity to start kmem tracing */ -} - -static int __init init_kmem_tracer(void) -{ - return register_tracer(&kmem_tracer); -} -device_initcall(init_kmem_tracer); diff --git a/kernel/trace/power-traces.c b/kernel/trace/power-traces.c new file mode 100644 index 00000000000..1c71382b283 --- /dev/null +++ b/kernel/trace/power-traces.c @@ -0,0 +1,17 @@ +/* + * Power trace points + * + * Copyright (C) 2009 Arjan van de Ven <arjan@linux.intel.com> + */ + +#include <linux/string.h> +#include <linux/types.h> +#include <linux/workqueue.h> +#include <linux/sched.h> +#include <linux/module.h> + +#define CREATE_TRACE_POINTS +#include <trace/events/power.h> + +EXPORT_TRACEPOINT_SYMBOL_GPL(cpu_idle); + diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index bf27bb7a63e..ff7027199a9 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -3,24 +3,31 @@ * * Copyright (C) 2008 Steven Rostedt <srostedt@redhat.com> */ +#include <linux/ftrace_event.h> #include <linux/ring_buffer.h> #include <linux/trace_clock.h> -#include <linux/ftrace_irq.h> +#include <linux/trace_seq.h> #include <linux/spinlock.h> +#include <linux/irq_work.h> #include <linux/debugfs.h> #include <linux/uaccess.h> #include <linux/hardirq.h> +#include <linux/kthread.h> /* for self test */ #include <linux/kmemcheck.h> #include <linux/module.h> #include <linux/percpu.h> #include <linux/mutex.h> +#include <linux/delay.h> +#include <linux/slab.h> #include <linux/init.h> #include <linux/hash.h> #include <linux/list.h> #include <linux/cpu.h> #include <linux/fs.h> -#include "trace.h" +#include <asm/local.h> + +static void update_pages_handler(struct work_struct *work); /* * The ring buffer header is special. We must manually up keep it. @@ -29,11 +36,11 @@ int ring_buffer_print_entry_header(struct trace_seq *s) { int ret; - ret = trace_seq_printf(s, "# compressed entry header\n"); - ret = trace_seq_printf(s, "\ttype_len : 5 bits\n"); - ret = trace_seq_printf(s, "\ttime_delta : 27 bits\n"); - ret = trace_seq_printf(s, "\tarray : 32 bits\n"); - ret = trace_seq_printf(s, "\n"); + ret = trace_seq_puts(s, "# compressed entry header\n"); + ret = trace_seq_puts(s, "\ttype_len : 5 bits\n"); + ret = trace_seq_puts(s, "\ttime_delta : 27 bits\n"); + ret = trace_seq_puts(s, "\tarray : 32 bits\n"); + ret = trace_seq_putc(s, '\n'); ret = trace_seq_printf(s, "\tpadding : type == %d\n", RINGBUF_TYPE_PADDING); ret = trace_seq_printf(s, "\ttime_extend : type == %d\n", @@ -153,33 +160,10 @@ enum { static unsigned long ring_buffer_flags __read_mostly = RB_BUFFERS_ON; -#define BUF_PAGE_HDR_SIZE offsetof(struct buffer_data_page, data) +/* Used for individual buffers (after the counter) */ +#define RB_BUFFER_OFF (1 << 20) -/** - * tracing_on - enable all tracing buffers - * - * This function enables all tracing buffers that may have been - * disabled with tracing_off. - */ -void tracing_on(void) -{ - set_bit(RB_BUFFERS_ON_BIT, &ring_buffer_flags); -} -EXPORT_SYMBOL_GPL(tracing_on); - -/** - * tracing_off - turn off all tracing buffers - * - * This function stops all tracing buffers from recording data. - * It does not disable any overhead the tracers themselves may - * be causing. This function simply causes all recording to - * the ring buffers to fail. - */ -void tracing_off(void) -{ - clear_bit(RB_BUFFERS_ON_BIT, &ring_buffer_flags); -} -EXPORT_SYMBOL_GPL(tracing_off); +#define BUF_PAGE_HDR_SIZE offsetof(struct buffer_data_page, data) /** * tracing_off_permanent - permanently disable ring buffers @@ -192,22 +176,21 @@ void tracing_off_permanent(void) set_bit(RB_BUFFERS_DISABLED_BIT, &ring_buffer_flags); } -/** - * tracing_is_on - show state of ring buffers enabled - */ -int tracing_is_on(void) -{ - return ring_buffer_flags == RB_BUFFERS_ON; -} -EXPORT_SYMBOL_GPL(tracing_is_on); - -#include "trace.h" - #define RB_EVNT_HDR_SIZE (offsetof(struct ring_buffer_event, array)) #define RB_ALIGNMENT 4U #define RB_MAX_SMALL_DATA (RB_ALIGNMENT * RINGBUF_TYPE_DATA_TYPE_LEN_MAX) #define RB_EVNT_MIN_SIZE 8U /* two 32bit words */ +#ifndef CONFIG_HAVE_64BIT_ALIGNED_ACCESS +# define RB_FORCE_8BYTE_ALIGNMENT 0 +# define RB_ARCH_ALIGNMENT RB_ALIGNMENT +#else +# define RB_FORCE_8BYTE_ALIGNMENT 1 +# define RB_ARCH_ALIGNMENT 8U +#endif + +#define RB_ALIGN_DATA __aligned(RB_ARCH_ALIGNMENT) + /* define RINGBUF_TYPE_DATA for 'case RINGBUF_TYPE_DATA:' */ #define RINGBUF_TYPE_DATA 0 ... RINGBUF_TYPE_DATA_TYPE_LEN_MAX @@ -216,19 +199,17 @@ enum { RB_LEN_TIME_STAMP = 16, }; -static inline int rb_null_event(struct ring_buffer_event *event) -{ - return event->type_len == RINGBUF_TYPE_PADDING - && event->time_delta == 0; -} +#define skip_time_extend(event) \ + ((struct ring_buffer_event *)((char *)event + RB_LEN_TIME_EXTEND)) -static inline int rb_discarded_event(struct ring_buffer_event *event) +static inline int rb_null_event(struct ring_buffer_event *event) { - return event->type_len == RINGBUF_TYPE_PADDING && event->time_delta; + return event->type_len == RINGBUF_TYPE_PADDING && !event->time_delta; } static void rb_event_set_padding(struct ring_buffer_event *event) { + /* padding has a NULL time_delta */ event->type_len = RINGBUF_TYPE_PADDING; event->time_delta = 0; } @@ -245,8 +226,12 @@ rb_event_data_length(struct ring_buffer_event *event) return length + RB_EVNT_HDR_SIZE; } -/* inline for ring buffer fast paths */ -static unsigned +/* + * Return the length of the given event. Will return + * the length of the time extend if the event is a + * time extend. + */ +static inline unsigned rb_event_length(struct ring_buffer_event *event) { switch (event->type_len) { @@ -271,13 +256,41 @@ rb_event_length(struct ring_buffer_event *event) return 0; } +/* + * Return total length of time extend and data, + * or just the event length for all other events. + */ +static inline unsigned +rb_event_ts_length(struct ring_buffer_event *event) +{ + unsigned len = 0; + + if (event->type_len == RINGBUF_TYPE_TIME_EXTEND) { + /* time extends include the data event after it */ + len = RB_LEN_TIME_EXTEND; + event = skip_time_extend(event); + } + return len + rb_event_length(event); +} + /** * ring_buffer_event_length - return the length of the event * @event: the event to get the length of + * + * Returns the size of the data load of a data event. + * If the event is something other than a data event, it + * returns the size of the event itself. With the exception + * of a TIME EXTEND, where it still returns the size of the + * data load of the data event after it. */ unsigned ring_buffer_event_length(struct ring_buffer_event *event) { - unsigned length = rb_event_length(event); + unsigned length; + + if (event->type_len == RINGBUF_TYPE_TIME_EXTEND) + event = skip_time_extend(event); + + length = rb_event_length(event); if (event->type_len > RINGBUF_TYPE_DATA_TYPE_LEN_MAX) return length; length -= RB_EVNT_HDR_SIZE; @@ -291,6 +304,8 @@ EXPORT_SYMBOL_GPL(ring_buffer_event_length); static void * rb_event_data(struct ring_buffer_event *event) { + if (event->type_len == RINGBUF_TYPE_TIME_EXTEND) + event = skip_time_extend(event); BUG_ON(event->type_len > RINGBUF_TYPE_DATA_TYPE_LEN_MAX); /* If length is in len field, then array[0] has the data */ if (event->type_len) @@ -316,20 +331,49 @@ EXPORT_SYMBOL_GPL(ring_buffer_event_data); #define TS_MASK ((1ULL << TS_SHIFT) - 1) #define TS_DELTA_TEST (~TS_MASK) +/* Flag when events were overwritten */ +#define RB_MISSED_EVENTS (1 << 31) +/* Missed count stored at end */ +#define RB_MISSED_STORED (1 << 30) + struct buffer_data_page { u64 time_stamp; /* page time stamp */ local_t commit; /* write committed index */ - unsigned char data[]; /* data of buffer page */ + unsigned char data[] RB_ALIGN_DATA; /* data of buffer page */ }; +/* + * Note, the buffer_page list must be first. The buffer pages + * are allocated in cache lines, which means that each buffer + * page will be at the beginning of a cache line, and thus + * the least significant bits will be zero. We use this to + * add flags in the list struct pointers, to make the ring buffer + * lockless. + */ struct buffer_page { struct list_head list; /* list of buffer pages */ local_t write; /* index for next write */ unsigned read; /* index for next read */ local_t entries; /* entries on this page */ + unsigned long real_end; /* real end of data */ struct buffer_data_page *page; /* Actual data page */ }; +/* + * The buffer page counters, write and entries, must be reset + * atomically when crossing page boundaries. To synchronize this + * update, two counters are inserted into the number. One is + * the actual counter for the write position or count on the page. + * + * The other is a counter of updaters. Before an update happens + * the update partition of the counter is incremented. This will + * allow the updater to update the counter atomically. + * + * The counter is 20 bits, and the state data is 12. + */ +#define RB_WRITE_MASK 0xfffff +#define RB_WRITE_INTCNT (1 << 20) + static void rb_init_page(struct buffer_data_page *bpage) { local_set(&bpage->commit, 0); @@ -372,62 +416,86 @@ static inline int test_time_stamp(u64 delta) /* Max payload is BUF_PAGE_SIZE - header (8bytes) */ #define BUF_MAX_DATA_SIZE (BUF_PAGE_SIZE - (sizeof(u32) * 2)) -/* Max number of timestamps that can fit on a page */ -#define RB_TIMESTAMPS_PER_PAGE (BUF_PAGE_SIZE / RB_LEN_TIME_STAMP) - int ring_buffer_print_page_header(struct trace_seq *s) { struct buffer_data_page field; int ret; ret = trace_seq_printf(s, "\tfield: u64 timestamp;\t" - "offset:0;\tsize:%u;\n", - (unsigned int)sizeof(field.time_stamp)); + "offset:0;\tsize:%u;\tsigned:%u;\n", + (unsigned int)sizeof(field.time_stamp), + (unsigned int)is_signed_type(u64)); ret = trace_seq_printf(s, "\tfield: local_t commit;\t" - "offset:%u;\tsize:%u;\n", + "offset:%u;\tsize:%u;\tsigned:%u;\n", + (unsigned int)offsetof(typeof(field), commit), + (unsigned int)sizeof(field.commit), + (unsigned int)is_signed_type(long)); + + ret = trace_seq_printf(s, "\tfield: int overwrite;\t" + "offset:%u;\tsize:%u;\tsigned:%u;\n", (unsigned int)offsetof(typeof(field), commit), - (unsigned int)sizeof(field.commit)); + 1, + (unsigned int)is_signed_type(long)); ret = trace_seq_printf(s, "\tfield: char data;\t" - "offset:%u;\tsize:%u;\n", + "offset:%u;\tsize:%u;\tsigned:%u;\n", (unsigned int)offsetof(typeof(field), data), - (unsigned int)BUF_PAGE_SIZE); + (unsigned int)BUF_PAGE_SIZE, + (unsigned int)is_signed_type(char)); return ret; } +struct rb_irq_work { + struct irq_work work; + wait_queue_head_t waiters; + bool waiters_pending; +}; + /* * head_page == tail_page && head == tail then buffer is empty. */ struct ring_buffer_per_cpu { int cpu; + atomic_t record_disabled; struct ring_buffer *buffer; - spinlock_t reader_lock; /* serialize readers */ - raw_spinlock_t lock; + raw_spinlock_t reader_lock; /* serialize readers */ + arch_spinlock_t lock; struct lock_class_key lock_key; - struct list_head pages; + unsigned int nr_pages; + struct list_head *pages; struct buffer_page *head_page; /* read from head */ struct buffer_page *tail_page; /* write to tail */ struct buffer_page *commit_page; /* committed pages */ struct buffer_page *reader_page; - unsigned long nmi_dropped; - unsigned long commit_overrun; - unsigned long overrun; - unsigned long read; + unsigned long lost_events; + unsigned long last_overrun; + local_t entries_bytes; local_t entries; + local_t overrun; + local_t commit_overrun; + local_t dropped_events; local_t committing; local_t commits; + unsigned long read; + unsigned long read_bytes; u64 write_stamp; u64 read_stamp; - atomic_t record_disabled; + /* ring buffer pages to update, > 0 to add, < 0 to remove */ + int nr_pages_to_update; + struct list_head new_pages; /* new pages to add */ + struct work_struct update_pages_work; + struct completion update_done; + + struct rb_irq_work irq_work; }; struct ring_buffer { - unsigned pages; unsigned flags; int cpus; atomic_t record_disabled; + atomic_t resize_disabled; cpumask_var_t cpumask; struct lock_class_key *reader_lock_key; @@ -440,30 +508,153 @@ struct ring_buffer { struct notifier_block cpu_notify; #endif u64 (*clock)(void); + + struct rb_irq_work irq_work; }; struct ring_buffer_iter { struct ring_buffer_per_cpu *cpu_buffer; unsigned long head; struct buffer_page *head_page; + struct buffer_page *cache_reader_page; + unsigned long cache_read; u64 read_stamp; }; +/* + * rb_wake_up_waiters - wake up tasks waiting for ring buffer input + * + * Schedules a delayed work to wake up any task that is blocked on the + * ring buffer waiters queue. + */ +static void rb_wake_up_waiters(struct irq_work *work) +{ + struct rb_irq_work *rbwork = container_of(work, struct rb_irq_work, work); + + wake_up_all(&rbwork->waiters); +} + +/** + * ring_buffer_wait - wait for input to the ring buffer + * @buffer: buffer to wait on + * @cpu: the cpu buffer to wait on + * + * If @cpu == RING_BUFFER_ALL_CPUS then the task will wake up as soon + * as data is added to any of the @buffer's cpu buffers. Otherwise + * it will wait for data to be added to a specific cpu buffer. + */ +int ring_buffer_wait(struct ring_buffer *buffer, int cpu) +{ + struct ring_buffer_per_cpu *cpu_buffer; + DEFINE_WAIT(wait); + struct rb_irq_work *work; + + /* + * Depending on what the caller is waiting for, either any + * data in any cpu buffer, or a specific buffer, put the + * caller on the appropriate wait queue. + */ + if (cpu == RING_BUFFER_ALL_CPUS) + work = &buffer->irq_work; + else { + if (!cpumask_test_cpu(cpu, buffer->cpumask)) + return -ENODEV; + cpu_buffer = buffer->buffers[cpu]; + work = &cpu_buffer->irq_work; + } + + + prepare_to_wait(&work->waiters, &wait, TASK_INTERRUPTIBLE); + + /* + * The events can happen in critical sections where + * checking a work queue can cause deadlocks. + * After adding a task to the queue, this flag is set + * only to notify events to try to wake up the queue + * using irq_work. + * + * We don't clear it even if the buffer is no longer + * empty. The flag only causes the next event to run + * irq_work to do the work queue wake up. The worse + * that can happen if we race with !trace_empty() is that + * an event will cause an irq_work to try to wake up + * an empty queue. + * + * There's no reason to protect this flag either, as + * the work queue and irq_work logic will do the necessary + * synchronization for the wake ups. The only thing + * that is necessary is that the wake up happens after + * a task has been queued. It's OK for spurious wake ups. + */ + work->waiters_pending = true; + + if ((cpu == RING_BUFFER_ALL_CPUS && ring_buffer_empty(buffer)) || + (cpu != RING_BUFFER_ALL_CPUS && ring_buffer_empty_cpu(buffer, cpu))) + schedule(); + + finish_wait(&work->waiters, &wait); + return 0; +} + +/** + * ring_buffer_poll_wait - poll on buffer input + * @buffer: buffer to wait on + * @cpu: the cpu buffer to wait on + * @filp: the file descriptor + * @poll_table: The poll descriptor + * + * If @cpu == RING_BUFFER_ALL_CPUS then the task will wake up as soon + * as data is added to any of the @buffer's cpu buffers. Otherwise + * it will wait for data to be added to a specific cpu buffer. + * + * Returns POLLIN | POLLRDNORM if data exists in the buffers, + * zero otherwise. + */ +int ring_buffer_poll_wait(struct ring_buffer *buffer, int cpu, + struct file *filp, poll_table *poll_table) +{ + struct ring_buffer_per_cpu *cpu_buffer; + struct rb_irq_work *work; + + if (cpu == RING_BUFFER_ALL_CPUS) + work = &buffer->irq_work; + else { + if (!cpumask_test_cpu(cpu, buffer->cpumask)) + return -EINVAL; + + cpu_buffer = buffer->buffers[cpu]; + work = &cpu_buffer->irq_work; + } + + work->waiters_pending = true; + poll_wait(filp, &work->waiters, poll_table); + + if ((cpu == RING_BUFFER_ALL_CPUS && !ring_buffer_empty(buffer)) || + (cpu != RING_BUFFER_ALL_CPUS && !ring_buffer_empty_cpu(buffer, cpu))) + return POLLIN | POLLRDNORM; + return 0; +} + /* buffer may be either ring_buffer or ring_buffer_per_cpu */ -#define RB_WARN_ON(buffer, cond) \ - ({ \ - int _____ret = unlikely(cond); \ - if (_____ret) { \ - atomic_inc(&buffer->record_disabled); \ - WARN_ON(1); \ - } \ - _____ret; \ +#define RB_WARN_ON(b, cond) \ + ({ \ + int _____ret = unlikely(cond); \ + if (_____ret) { \ + if (__same_type(*(b), struct ring_buffer_per_cpu)) { \ + struct ring_buffer_per_cpu *__b = \ + (void *)b; \ + atomic_inc(&__b->buffer->record_disabled); \ + } else \ + atomic_inc(&b->record_disabled); \ + WARN_ON(1); \ + } \ + _____ret; \ }) /* Up this if you want to test the TIME_EXTENTS and normalization */ #define DEBUG_SHIFT 0 -static inline u64 rb_time_stamp(struct ring_buffer *buffer, int cpu) +static inline u64 rb_time_stamp(struct ring_buffer *buffer) { /* shift to debug/test normalization and TIME_EXTENTS */ return buffer->clock() << DEBUG_SHIFT; @@ -474,7 +665,7 @@ u64 ring_buffer_time_stamp(struct ring_buffer *buffer, int cpu) u64 time; preempt_disable_notrace(); - time = rb_time_stamp(buffer, cpu); + time = rb_time_stamp(buffer); preempt_enable_no_resched_notrace(); return time; @@ -489,8 +680,392 @@ void ring_buffer_normalize_time_stamp(struct ring_buffer *buffer, } EXPORT_SYMBOL_GPL(ring_buffer_normalize_time_stamp); +/* + * Making the ring buffer lockless makes things tricky. + * Although writes only happen on the CPU that they are on, + * and they only need to worry about interrupts. Reads can + * happen on any CPU. + * + * The reader page is always off the ring buffer, but when the + * reader finishes with a page, it needs to swap its page with + * a new one from the buffer. The reader needs to take from + * the head (writes go to the tail). But if a writer is in overwrite + * mode and wraps, it must push the head page forward. + * + * Here lies the problem. + * + * The reader must be careful to replace only the head page, and + * not another one. As described at the top of the file in the + * ASCII art, the reader sets its old page to point to the next + * page after head. It then sets the page after head to point to + * the old reader page. But if the writer moves the head page + * during this operation, the reader could end up with the tail. + * + * We use cmpxchg to help prevent this race. We also do something + * special with the page before head. We set the LSB to 1. + * + * When the writer must push the page forward, it will clear the + * bit that points to the head page, move the head, and then set + * the bit that points to the new head page. + * + * We also don't want an interrupt coming in and moving the head + * page on another writer. Thus we use the second LSB to catch + * that too. Thus: + * + * head->list->prev->next bit 1 bit 0 + * ------- ------- + * Normal page 0 0 + * Points to head page 0 1 + * New head page 1 0 + * + * Note we can not trust the prev pointer of the head page, because: + * + * +----+ +-----+ +-----+ + * | |------>| T |---X--->| N | + * | |<------| | | | + * +----+ +-----+ +-----+ + * ^ ^ | + * | +-----+ | | + * +----------| R |----------+ | + * | |<-----------+ + * +-----+ + * + * Key: ---X--> HEAD flag set in pointer + * T Tail page + * R Reader page + * N Next page + * + * (see __rb_reserve_next() to see where this happens) + * + * What the above shows is that the reader just swapped out + * the reader page with a page in the buffer, but before it + * could make the new header point back to the new page added + * it was preempted by a writer. The writer moved forward onto + * the new page added by the reader and is about to move forward + * again. + * + * You can see, it is legitimate for the previous pointer of + * the head (or any page) not to point back to itself. But only + * temporarially. + */ + +#define RB_PAGE_NORMAL 0UL +#define RB_PAGE_HEAD 1UL +#define RB_PAGE_UPDATE 2UL + + +#define RB_FLAG_MASK 3UL + +/* PAGE_MOVED is not part of the mask */ +#define RB_PAGE_MOVED 4UL + +/* + * rb_list_head - remove any bit + */ +static struct list_head *rb_list_head(struct list_head *list) +{ + unsigned long val = (unsigned long)list; + + return (struct list_head *)(val & ~RB_FLAG_MASK); +} + +/* + * rb_is_head_page - test if the given page is the head page + * + * Because the reader may move the head_page pointer, we can + * not trust what the head page is (it may be pointing to + * the reader page). But if the next page is a header page, + * its flags will be non zero. + */ +static inline int +rb_is_head_page(struct ring_buffer_per_cpu *cpu_buffer, + struct buffer_page *page, struct list_head *list) +{ + unsigned long val; + + val = (unsigned long)list->next; + + if ((val & ~RB_FLAG_MASK) != (unsigned long)&page->list) + return RB_PAGE_MOVED; + + return val & RB_FLAG_MASK; +} + +/* + * rb_is_reader_page + * + * The unique thing about the reader page, is that, if the + * writer is ever on it, the previous pointer never points + * back to the reader page. + */ +static int rb_is_reader_page(struct buffer_page *page) +{ + struct list_head *list = page->list.prev; + + return rb_list_head(list->next) != &page->list; +} + +/* + * rb_set_list_to_head - set a list_head to be pointing to head. + */ +static void rb_set_list_to_head(struct ring_buffer_per_cpu *cpu_buffer, + struct list_head *list) +{ + unsigned long *ptr; + + ptr = (unsigned long *)&list->next; + *ptr |= RB_PAGE_HEAD; + *ptr &= ~RB_PAGE_UPDATE; +} + +/* + * rb_head_page_activate - sets up head page + */ +static void rb_head_page_activate(struct ring_buffer_per_cpu *cpu_buffer) +{ + struct buffer_page *head; + + head = cpu_buffer->head_page; + if (!head) + return; + + /* + * Set the previous list pointer to have the HEAD flag. + */ + rb_set_list_to_head(cpu_buffer, head->list.prev); +} + +static void rb_list_head_clear(struct list_head *list) +{ + unsigned long *ptr = (unsigned long *)&list->next; + + *ptr &= ~RB_FLAG_MASK; +} + +/* + * rb_head_page_dactivate - clears head page ptr (for free list) + */ +static void +rb_head_page_deactivate(struct ring_buffer_per_cpu *cpu_buffer) +{ + struct list_head *hd; + + /* Go through the whole list and clear any pointers found. */ + rb_list_head_clear(cpu_buffer->pages); + + list_for_each(hd, cpu_buffer->pages) + rb_list_head_clear(hd); +} + +static int rb_head_page_set(struct ring_buffer_per_cpu *cpu_buffer, + struct buffer_page *head, + struct buffer_page *prev, + int old_flag, int new_flag) +{ + struct list_head *list; + unsigned long val = (unsigned long)&head->list; + unsigned long ret; + + list = &prev->list; + + val &= ~RB_FLAG_MASK; + + ret = cmpxchg((unsigned long *)&list->next, + val | old_flag, val | new_flag); + + /* check if the reader took the page */ + if ((ret & ~RB_FLAG_MASK) != val) + return RB_PAGE_MOVED; + + return ret & RB_FLAG_MASK; +} + +static int rb_head_page_set_update(struct ring_buffer_per_cpu *cpu_buffer, + struct buffer_page *head, + struct buffer_page *prev, + int old_flag) +{ + return rb_head_page_set(cpu_buffer, head, prev, + old_flag, RB_PAGE_UPDATE); +} + +static int rb_head_page_set_head(struct ring_buffer_per_cpu *cpu_buffer, + struct buffer_page *head, + struct buffer_page *prev, + int old_flag) +{ + return rb_head_page_set(cpu_buffer, head, prev, + old_flag, RB_PAGE_HEAD); +} + +static int rb_head_page_set_normal(struct ring_buffer_per_cpu *cpu_buffer, + struct buffer_page *head, + struct buffer_page *prev, + int old_flag) +{ + return rb_head_page_set(cpu_buffer, head, prev, + old_flag, RB_PAGE_NORMAL); +} + +static inline void rb_inc_page(struct ring_buffer_per_cpu *cpu_buffer, + struct buffer_page **bpage) +{ + struct list_head *p = rb_list_head((*bpage)->list.next); + + *bpage = list_entry(p, struct buffer_page, list); +} + +static struct buffer_page * +rb_set_head_page(struct ring_buffer_per_cpu *cpu_buffer) +{ + struct buffer_page *head; + struct buffer_page *page; + struct list_head *list; + int i; + + if (RB_WARN_ON(cpu_buffer, !cpu_buffer->head_page)) + return NULL; + + /* sanity check */ + list = cpu_buffer->pages; + if (RB_WARN_ON(cpu_buffer, rb_list_head(list->prev->next) != list)) + return NULL; + + page = head = cpu_buffer->head_page; + /* + * It is possible that the writer moves the header behind + * where we started, and we miss in one loop. + * A second loop should grab the header, but we'll do + * three loops just because I'm paranoid. + */ + for (i = 0; i < 3; i++) { + do { + if (rb_is_head_page(cpu_buffer, page, page->list.prev)) { + cpu_buffer->head_page = page; + return page; + } + rb_inc_page(cpu_buffer, &page); + } while (page != head); + } + + RB_WARN_ON(cpu_buffer, 1); + + return NULL; +} + +static int rb_head_page_replace(struct buffer_page *old, + struct buffer_page *new) +{ + unsigned long *ptr = (unsigned long *)&old->list.prev->next; + unsigned long val; + unsigned long ret; + + val = *ptr & ~RB_FLAG_MASK; + val |= RB_PAGE_HEAD; + + ret = cmpxchg(ptr, val, (unsigned long)&new->list); + + return ret == val; +} + +/* + * rb_tail_page_update - move the tail page forward + * + * Returns 1 if moved tail page, 0 if someone else did. + */ +static int rb_tail_page_update(struct ring_buffer_per_cpu *cpu_buffer, + struct buffer_page *tail_page, + struct buffer_page *next_page) +{ + struct buffer_page *old_tail; + unsigned long old_entries; + unsigned long old_write; + int ret = 0; + + /* + * The tail page now needs to be moved forward. + * + * We need to reset the tail page, but without messing + * with possible erasing of data brought in by interrupts + * that have moved the tail page and are currently on it. + * + * We add a counter to the write field to denote this. + */ + old_write = local_add_return(RB_WRITE_INTCNT, &next_page->write); + old_entries = local_add_return(RB_WRITE_INTCNT, &next_page->entries); + + /* + * Just make sure we have seen our old_write and synchronize + * with any interrupts that come in. + */ + barrier(); + + /* + * If the tail page is still the same as what we think + * it is, then it is up to us to update the tail + * pointer. + */ + if (tail_page == cpu_buffer->tail_page) { + /* Zero the write counter */ + unsigned long val = old_write & ~RB_WRITE_MASK; + unsigned long eval = old_entries & ~RB_WRITE_MASK; + + /* + * This will only succeed if an interrupt did + * not come in and change it. In which case, we + * do not want to modify it. + * + * We add (void) to let the compiler know that we do not care + * about the return value of these functions. We use the + * cmpxchg to only update if an interrupt did not already + * do it for us. If the cmpxchg fails, we don't care. + */ + (void)local_cmpxchg(&next_page->write, old_write, val); + (void)local_cmpxchg(&next_page->entries, old_entries, eval); + + /* + * No need to worry about races with clearing out the commit. + * it only can increment when a commit takes place. But that + * only happens in the outer most nested commit. + */ + local_set(&next_page->page->commit, 0); + + old_tail = cmpxchg(&cpu_buffer->tail_page, + tail_page, next_page); + + if (old_tail == tail_page) + ret = 1; + } + + return ret; +} + +static int rb_check_bpage(struct ring_buffer_per_cpu *cpu_buffer, + struct buffer_page *bpage) +{ + unsigned long val = (unsigned long)bpage; + + if (RB_WARN_ON(cpu_buffer, val & RB_FLAG_MASK)) + return 1; + + return 0; +} + /** - * check_pages - integrity check of buffer pages + * rb_check_list - make sure a pointer to a list has the last bits zero + */ +static int rb_check_list(struct ring_buffer_per_cpu *cpu_buffer, + struct list_head *list) +{ + if (RB_WARN_ON(cpu_buffer, rb_list_head(list->prev) != list->prev)) + return 1; + if (RB_WARN_ON(cpu_buffer, rb_list_head(list->next) != list->next)) + return 1; + return 0; +} + +/** + * rb_check_pages - integrity check of buffer pages * @cpu_buffer: CPU buffer with pages to test * * As a safety measure we check to make sure the data pages have not @@ -498,14 +1073,23 @@ EXPORT_SYMBOL_GPL(ring_buffer_normalize_time_stamp); */ static int rb_check_pages(struct ring_buffer_per_cpu *cpu_buffer) { - struct list_head *head = &cpu_buffer->pages; + struct list_head *head = cpu_buffer->pages; struct buffer_page *bpage, *tmp; + /* Reset the head page if it exists */ + if (cpu_buffer->head_page) + rb_set_head_page(cpu_buffer); + + rb_head_page_deactivate(cpu_buffer); + if (RB_WARN_ON(cpu_buffer, head->next->prev != head)) return -1; if (RB_WARN_ON(cpu_buffer, head->prev->next != head)) return -1; + if (rb_check_list(cpu_buffer, head)) + return -1; + list_for_each_entry_safe(bpage, tmp, head, list) { if (RB_WARN_ON(cpu_buffer, bpage->list.next->prev != &bpage->list)) @@ -513,54 +1097,85 @@ static int rb_check_pages(struct ring_buffer_per_cpu *cpu_buffer) if (RB_WARN_ON(cpu_buffer, bpage->list.prev->next != &bpage->list)) return -1; + if (rb_check_list(cpu_buffer, &bpage->list)) + return -1; } + rb_head_page_activate(cpu_buffer); + return 0; } -static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer, - unsigned nr_pages) +static int __rb_allocate_pages(int nr_pages, struct list_head *pages, int cpu) { - struct list_head *head = &cpu_buffer->pages; + int i; struct buffer_page *bpage, *tmp; - unsigned long addr; - LIST_HEAD(pages); - unsigned i; for (i = 0; i < nr_pages; i++) { + struct page *page; + /* + * __GFP_NORETRY flag makes sure that the allocation fails + * gracefully without invoking oom-killer and the system is + * not destabilized. + */ bpage = kzalloc_node(ALIGN(sizeof(*bpage), cache_line_size()), - GFP_KERNEL, cpu_to_node(cpu_buffer->cpu)); + GFP_KERNEL | __GFP_NORETRY, + cpu_to_node(cpu)); if (!bpage) goto free_pages; - list_add(&bpage->list, &pages); - addr = __get_free_page(GFP_KERNEL); - if (!addr) + list_add(&bpage->list, pages); + + page = alloc_pages_node(cpu_to_node(cpu), + GFP_KERNEL | __GFP_NORETRY, 0); + if (!page) goto free_pages; - bpage->page = (void *)addr; + bpage->page = page_address(page); rb_init_page(bpage->page); } - list_splice(&pages, head); - - rb_check_pages(cpu_buffer); - return 0; - free_pages: - list_for_each_entry_safe(bpage, tmp, &pages, list) { +free_pages: + list_for_each_entry_safe(bpage, tmp, pages, list) { list_del_init(&bpage->list); free_buffer_page(bpage); } + return -ENOMEM; } +static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer, + unsigned nr_pages) +{ + LIST_HEAD(pages); + + WARN_ON(!nr_pages); + + if (__rb_allocate_pages(nr_pages, &pages, cpu_buffer->cpu)) + return -ENOMEM; + + /* + * The ring buffer page list is a circular list that does not + * start and end with a list head. All page list items point to + * other pages. + */ + cpu_buffer->pages = pages.next; + list_del(&pages); + + cpu_buffer->nr_pages = nr_pages; + + rb_check_pages(cpu_buffer); + + return 0; +} + static struct ring_buffer_per_cpu * -rb_allocate_cpu_buffer(struct ring_buffer *buffer, int cpu) +rb_allocate_cpu_buffer(struct ring_buffer *buffer, int nr_pages, int cpu) { struct ring_buffer_per_cpu *cpu_buffer; struct buffer_page *bpage; - unsigned long addr; + struct page *page; int ret; cpu_buffer = kzalloc_node(ALIGN(sizeof(*cpu_buffer), cache_line_size()), @@ -570,33 +1185,41 @@ rb_allocate_cpu_buffer(struct ring_buffer *buffer, int cpu) cpu_buffer->cpu = cpu; cpu_buffer->buffer = buffer; - spin_lock_init(&cpu_buffer->reader_lock); + raw_spin_lock_init(&cpu_buffer->reader_lock); lockdep_set_class(&cpu_buffer->reader_lock, buffer->reader_lock_key); - cpu_buffer->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; - INIT_LIST_HEAD(&cpu_buffer->pages); + cpu_buffer->lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; + INIT_WORK(&cpu_buffer->update_pages_work, update_pages_handler); + init_completion(&cpu_buffer->update_done); + init_irq_work(&cpu_buffer->irq_work.work, rb_wake_up_waiters); + init_waitqueue_head(&cpu_buffer->irq_work.waiters); bpage = kzalloc_node(ALIGN(sizeof(*bpage), cache_line_size()), GFP_KERNEL, cpu_to_node(cpu)); if (!bpage) goto fail_free_buffer; + rb_check_bpage(cpu_buffer, bpage); + cpu_buffer->reader_page = bpage; - addr = __get_free_page(GFP_KERNEL); - if (!addr) + page = alloc_pages_node(cpu_to_node(cpu), GFP_KERNEL, 0); + if (!page) goto fail_free_reader; - bpage->page = (void *)addr; + bpage->page = page_address(page); rb_init_page(bpage->page); INIT_LIST_HEAD(&cpu_buffer->reader_page->list); + INIT_LIST_HEAD(&cpu_buffer->new_pages); - ret = rb_allocate_pages(cpu_buffer, buffer->pages); + ret = rb_allocate_pages(cpu_buffer, nr_pages); if (ret < 0) goto fail_free_reader; cpu_buffer->head_page - = list_entry(cpu_buffer->pages.next, struct buffer_page, list); + = list_entry(cpu_buffer->pages, struct buffer_page, list); cpu_buffer->tail_page = cpu_buffer->commit_page = cpu_buffer->head_page; + rb_head_page_activate(cpu_buffer); + return cpu_buffer; fail_free_reader: @@ -609,15 +1232,22 @@ rb_allocate_cpu_buffer(struct ring_buffer *buffer, int cpu) static void rb_free_cpu_buffer(struct ring_buffer_per_cpu *cpu_buffer) { - struct list_head *head = &cpu_buffer->pages; + struct list_head *head = cpu_buffer->pages; struct buffer_page *bpage, *tmp; free_buffer_page(cpu_buffer->reader_page); - list_for_each_entry_safe(bpage, tmp, head, list) { - list_del_init(&bpage->list); + rb_head_page_deactivate(cpu_buffer); + + if (head) { + list_for_each_entry_safe(bpage, tmp, head, list) { + list_del_init(&bpage->list); + free_buffer_page(bpage); + } + bpage = list_entry(head, struct buffer_page, list); free_buffer_page(bpage); } + kfree(cpu_buffer); } @@ -627,7 +1257,7 @@ static int rb_cpu_notify(struct notifier_block *self, #endif /** - * ring_buffer_alloc - allocate a new ring_buffer + * __ring_buffer_alloc - allocate a new ring_buffer * @size: the size in bytes per cpu that is needed. * @flags: attributes to set for the ring buffer. * @@ -641,7 +1271,7 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags, { struct ring_buffer *buffer; int bsize; - int cpu; + int cpu, nr_pages; /* keep it in its own cache line */ buffer = kzalloc(ALIGN(sizeof(*buffer), cache_line_size()), @@ -652,14 +1282,17 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags, if (!alloc_cpumask_var(&buffer->cpumask, GFP_KERNEL)) goto fail_free_buffer; - buffer->pages = DIV_ROUND_UP(size, BUF_PAGE_SIZE); + nr_pages = DIV_ROUND_UP(size, BUF_PAGE_SIZE); buffer->flags = flags; buffer->clock = trace_clock_local; buffer->reader_lock_key = key; + init_irq_work(&buffer->irq_work.work, rb_wake_up_waiters); + init_waitqueue_head(&buffer->irq_work.waiters); + /* need at least two pages */ - if (buffer->pages < 2) - buffer->pages = 2; + if (nr_pages < 2) + nr_pages = 2; /* * In case of non-hotplug cpu, if the ring-buffer is allocated @@ -667,7 +1300,7 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags, * In that off case, we need to allocate for all possible cpus. */ #ifdef CONFIG_HOTPLUG_CPU - get_online_cpus(); + cpu_notifier_register_begin(); cpumask_copy(buffer->cpumask, cpu_online_mask); #else cpumask_copy(buffer->cpumask, cpu_possible_mask); @@ -682,7 +1315,7 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags, for_each_buffer_cpu(buffer, cpu) { buffer->buffers[cpu] = - rb_allocate_cpu_buffer(buffer, cpu); + rb_allocate_cpu_buffer(buffer, nr_pages, cpu); if (!buffer->buffers[cpu]) goto fail_free_buffers; } @@ -690,10 +1323,10 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags, #ifdef CONFIG_HOTPLUG_CPU buffer->cpu_notify.notifier_call = rb_cpu_notify; buffer->cpu_notify.priority = 0; - register_cpu_notifier(&buffer->cpu_notify); + __register_cpu_notifier(&buffer->cpu_notify); + cpu_notifier_register_done(); #endif - put_online_cpus(); mutex_init(&buffer->mutex); return buffer; @@ -707,7 +1340,9 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags, fail_free_cpumask: free_cpumask_var(buffer->cpumask); - put_online_cpus(); +#ifdef CONFIG_HOTPLUG_CPU + cpu_notifier_register_done(); +#endif fail_free_buffer: kfree(buffer); @@ -724,17 +1359,19 @@ ring_buffer_free(struct ring_buffer *buffer) { int cpu; - get_online_cpus(); - #ifdef CONFIG_HOTPLUG_CPU - unregister_cpu_notifier(&buffer->cpu_notify); + cpu_notifier_register_begin(); + __unregister_cpu_notifier(&buffer->cpu_notify); #endif for_each_buffer_cpu(buffer, cpu) rb_free_cpu_buffer(buffer->buffers[cpu]); - put_online_cpus(); +#ifdef CONFIG_HOTPLUG_CPU + cpu_notifier_register_done(); +#endif + kfree(buffer->buffers); free_cpumask_var(buffer->cpumask); kfree(buffer); @@ -749,84 +1386,241 @@ void ring_buffer_set_clock(struct ring_buffer *buffer, static void rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer); -static void -rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned nr_pages) +static inline unsigned long rb_page_entries(struct buffer_page *bpage) { - struct buffer_page *bpage; - struct list_head *p; - unsigned i; + return local_read(&bpage->entries) & RB_WRITE_MASK; +} +static inline unsigned long rb_page_write(struct buffer_page *bpage) +{ + return local_read(&bpage->write) & RB_WRITE_MASK; +} + +static int +rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned int nr_pages) +{ + struct list_head *tail_page, *to_remove, *next_page; + struct buffer_page *to_remove_page, *tmp_iter_page; + struct buffer_page *last_page, *first_page; + unsigned int nr_removed; + unsigned long head_bit; + int page_entries; + + head_bit = 0; + + raw_spin_lock_irq(&cpu_buffer->reader_lock); atomic_inc(&cpu_buffer->record_disabled); - synchronize_sched(); + /* + * We don't race with the readers since we have acquired the reader + * lock. We also don't race with writers after disabling recording. + * This makes it easy to figure out the first and the last page to be + * removed from the list. We unlink all the pages in between including + * the first and last pages. This is done in a busy loop so that we + * lose the least number of traces. + * The pages are freed after we restart recording and unlock readers. + */ + tail_page = &cpu_buffer->tail_page->list; - for (i = 0; i < nr_pages; i++) { - if (RB_WARN_ON(cpu_buffer, list_empty(&cpu_buffer->pages))) - return; - p = cpu_buffer->pages.next; - bpage = list_entry(p, struct buffer_page, list); - list_del_init(&bpage->list); - free_buffer_page(bpage); + /* + * tail page might be on reader page, we remove the next page + * from the ring buffer + */ + if (cpu_buffer->tail_page == cpu_buffer->reader_page) + tail_page = rb_list_head(tail_page->next); + to_remove = tail_page; + + /* start of pages to remove */ + first_page = list_entry(rb_list_head(to_remove->next), + struct buffer_page, list); + + for (nr_removed = 0; nr_removed < nr_pages; nr_removed++) { + to_remove = rb_list_head(to_remove)->next; + head_bit |= (unsigned long)to_remove & RB_PAGE_HEAD; } - if (RB_WARN_ON(cpu_buffer, list_empty(&cpu_buffer->pages))) - return; - rb_reset_cpu(cpu_buffer); + next_page = rb_list_head(to_remove)->next; - rb_check_pages(cpu_buffer); + /* + * Now we remove all pages between tail_page and next_page. + * Make sure that we have head_bit value preserved for the + * next page + */ + tail_page->next = (struct list_head *)((unsigned long)next_page | + head_bit); + next_page = rb_list_head(next_page); + next_page->prev = tail_page; + + /* make sure pages points to a valid page in the ring buffer */ + cpu_buffer->pages = next_page; + + /* update head page */ + if (head_bit) + cpu_buffer->head_page = list_entry(next_page, + struct buffer_page, list); + + /* + * change read pointer to make sure any read iterators reset + * themselves + */ + cpu_buffer->read = 0; + /* pages are removed, resume tracing and then free the pages */ atomic_dec(&cpu_buffer->record_disabled); + raw_spin_unlock_irq(&cpu_buffer->reader_lock); + + RB_WARN_ON(cpu_buffer, list_empty(cpu_buffer->pages)); + + /* last buffer page to remove */ + last_page = list_entry(rb_list_head(to_remove), struct buffer_page, + list); + tmp_iter_page = first_page; + + do { + to_remove_page = tmp_iter_page; + rb_inc_page(cpu_buffer, &tmp_iter_page); + + /* update the counters */ + page_entries = rb_page_entries(to_remove_page); + if (page_entries) { + /* + * If something was added to this page, it was full + * since it is not the tail page. So we deduct the + * bytes consumed in ring buffer from here. + * Increment overrun to account for the lost events. + */ + local_add(page_entries, &cpu_buffer->overrun); + local_sub(BUF_PAGE_SIZE, &cpu_buffer->entries_bytes); + } + + /* + * We have already removed references to this list item, just + * free up the buffer_page and its page + */ + free_buffer_page(to_remove_page); + nr_removed--; + } while (to_remove_page != last_page); + + RB_WARN_ON(cpu_buffer, nr_removed); + + return nr_removed == 0; } -static void -rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer, - struct list_head *pages, unsigned nr_pages) +static int +rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer) { - struct buffer_page *bpage; - struct list_head *p; - unsigned i; + struct list_head *pages = &cpu_buffer->new_pages; + int retries, success; - atomic_inc(&cpu_buffer->record_disabled); - synchronize_sched(); + raw_spin_lock_irq(&cpu_buffer->reader_lock); + /* + * We are holding the reader lock, so the reader page won't be swapped + * in the ring buffer. Now we are racing with the writer trying to + * move head page and the tail page. + * We are going to adapt the reader page update process where: + * 1. We first splice the start and end of list of new pages between + * the head page and its previous page. + * 2. We cmpxchg the prev_page->next to point from head page to the + * start of new pages list. + * 3. Finally, we update the head->prev to the end of new list. + * + * We will try this process 10 times, to make sure that we don't keep + * spinning. + */ + retries = 10; + success = 0; + while (retries--) { + struct list_head *head_page, *prev_page, *r; + struct list_head *last_page, *first_page; + struct list_head *head_page_with_bit; + + head_page = &rb_set_head_page(cpu_buffer)->list; + if (!head_page) + break; + prev_page = head_page->prev; + + first_page = pages->next; + last_page = pages->prev; + + head_page_with_bit = (struct list_head *) + ((unsigned long)head_page | RB_PAGE_HEAD); + + last_page->next = head_page_with_bit; + first_page->prev = prev_page; + + r = cmpxchg(&prev_page->next, head_page_with_bit, first_page); + + if (r == head_page_with_bit) { + /* + * yay, we replaced the page pointer to our new list, + * now, we just have to update to head page's prev + * pointer to point to end of list + */ + head_page->prev = last_page; + success = 1; + break; + } + } - for (i = 0; i < nr_pages; i++) { - if (RB_WARN_ON(cpu_buffer, list_empty(pages))) - return; - p = pages->next; - bpage = list_entry(p, struct buffer_page, list); - list_del_init(&bpage->list); - list_add_tail(&bpage->list, &cpu_buffer->pages); + if (success) + INIT_LIST_HEAD(pages); + /* + * If we weren't successful in adding in new pages, warn and stop + * tracing + */ + RB_WARN_ON(cpu_buffer, !success); + raw_spin_unlock_irq(&cpu_buffer->reader_lock); + + /* free pages if they weren't inserted */ + if (!success) { + struct buffer_page *bpage, *tmp; + list_for_each_entry_safe(bpage, tmp, &cpu_buffer->new_pages, + list) { + list_del_init(&bpage->list); + free_buffer_page(bpage); + } } - rb_reset_cpu(cpu_buffer); + return success; +} - rb_check_pages(cpu_buffer); +static void rb_update_pages(struct ring_buffer_per_cpu *cpu_buffer) +{ + int success; - atomic_dec(&cpu_buffer->record_disabled); + if (cpu_buffer->nr_pages_to_update > 0) + success = rb_insert_pages(cpu_buffer); + else + success = rb_remove_pages(cpu_buffer, + -cpu_buffer->nr_pages_to_update); + + if (success) + cpu_buffer->nr_pages += cpu_buffer->nr_pages_to_update; +} + +static void update_pages_handler(struct work_struct *work) +{ + struct ring_buffer_per_cpu *cpu_buffer = container_of(work, + struct ring_buffer_per_cpu, update_pages_work); + rb_update_pages(cpu_buffer); + complete(&cpu_buffer->update_done); } /** * ring_buffer_resize - resize the ring buffer * @buffer: the buffer to resize. * @size: the new size. - * - * The tracer is responsible for making sure that the buffer is - * not being used while changing the size. - * Note: We may be able to change the above requirement by using - * RCU synchronizations. + * @cpu_id: the cpu buffer to resize * * Minimum size is 2 * BUF_PAGE_SIZE. * - * Returns -1 on failure. + * Returns 0 on success and < 0 on failure. */ -int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size) +int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size, + int cpu_id) { struct ring_buffer_per_cpu *cpu_buffer; - unsigned nr_pages, rm_pages, new_pages; - struct buffer_page *bpage, *tmp; - unsigned long buffer_size; - unsigned long addr; - LIST_HEAD(pages); - int i, cpu; + unsigned nr_pages; + int cpu, err = 0; /* * Always succeed at resizing a non-existent buffer: @@ -834,100 +1628,199 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size) if (!buffer) return size; + /* Make sure the requested buffer exists */ + if (cpu_id != RING_BUFFER_ALL_CPUS && + !cpumask_test_cpu(cpu_id, buffer->cpumask)) + return size; + size = DIV_ROUND_UP(size, BUF_PAGE_SIZE); size *= BUF_PAGE_SIZE; - buffer_size = buffer->pages * BUF_PAGE_SIZE; /* we need a minimum of two pages */ if (size < BUF_PAGE_SIZE * 2) size = BUF_PAGE_SIZE * 2; - if (size == buffer_size) - return size; + nr_pages = DIV_ROUND_UP(size, BUF_PAGE_SIZE); - mutex_lock(&buffer->mutex); - get_online_cpus(); + /* + * Don't succeed if resizing is disabled, as a reader might be + * manipulating the ring buffer and is expecting a sane state while + * this is true. + */ + if (atomic_read(&buffer->resize_disabled)) + return -EBUSY; - nr_pages = DIV_ROUND_UP(size, BUF_PAGE_SIZE); + /* prevent another thread from changing buffer sizes */ + mutex_lock(&buffer->mutex); - if (size < buffer_size) { + if (cpu_id == RING_BUFFER_ALL_CPUS) { + /* calculate the pages to update */ + for_each_buffer_cpu(buffer, cpu) { + cpu_buffer = buffer->buffers[cpu]; - /* easy case, just free pages */ - if (RB_WARN_ON(buffer, nr_pages >= buffer->pages)) - goto out_fail; + cpu_buffer->nr_pages_to_update = nr_pages - + cpu_buffer->nr_pages; + /* + * nothing more to do for removing pages or no update + */ + if (cpu_buffer->nr_pages_to_update <= 0) + continue; + /* + * to add pages, make sure all new pages can be + * allocated without receiving ENOMEM + */ + INIT_LIST_HEAD(&cpu_buffer->new_pages); + if (__rb_allocate_pages(cpu_buffer->nr_pages_to_update, + &cpu_buffer->new_pages, cpu)) { + /* not enough memory for new pages */ + err = -ENOMEM; + goto out_err; + } + } - rm_pages = buffer->pages - nr_pages; + get_online_cpus(); + /* + * Fire off all the required work handlers + * We can't schedule on offline CPUs, but it's not necessary + * since we can change their buffer sizes without any race. + */ + for_each_buffer_cpu(buffer, cpu) { + cpu_buffer = buffer->buffers[cpu]; + if (!cpu_buffer->nr_pages_to_update) + continue; + + /* The update must run on the CPU that is being updated. */ + preempt_disable(); + if (cpu == smp_processor_id() || !cpu_online(cpu)) { + rb_update_pages(cpu_buffer); + cpu_buffer->nr_pages_to_update = 0; + } else { + /* + * Can not disable preemption for schedule_work_on() + * on PREEMPT_RT. + */ + preempt_enable(); + schedule_work_on(cpu, + &cpu_buffer->update_pages_work); + preempt_disable(); + } + preempt_enable(); + } + /* wait for all the updates to complete */ for_each_buffer_cpu(buffer, cpu) { cpu_buffer = buffer->buffers[cpu]; - rb_remove_pages(cpu_buffer, rm_pages); + if (!cpu_buffer->nr_pages_to_update) + continue; + + if (cpu_online(cpu)) + wait_for_completion(&cpu_buffer->update_done); + cpu_buffer->nr_pages_to_update = 0; } - goto out; - } - /* - * This is a bit more difficult. We only want to add pages - * when we can allocate enough for all CPUs. We do this - * by allocating all the pages and storing them on a local - * link list. If we succeed in our allocation, then we - * add these pages to the cpu_buffers. Otherwise we just free - * them all and return -ENOMEM; - */ - if (RB_WARN_ON(buffer, nr_pages <= buffer->pages)) - goto out_fail; + put_online_cpus(); + } else { + /* Make sure this CPU has been intitialized */ + if (!cpumask_test_cpu(cpu_id, buffer->cpumask)) + goto out; - new_pages = nr_pages - buffer->pages; + cpu_buffer = buffer->buffers[cpu_id]; - for_each_buffer_cpu(buffer, cpu) { - for (i = 0; i < new_pages; i++) { - bpage = kzalloc_node(ALIGN(sizeof(*bpage), - cache_line_size()), - GFP_KERNEL, cpu_to_node(cpu)); - if (!bpage) - goto free_pages; - list_add(&bpage->list, &pages); - addr = __get_free_page(GFP_KERNEL); - if (!addr) - goto free_pages; - bpage->page = (void *)addr; - rb_init_page(bpage->page); + if (nr_pages == cpu_buffer->nr_pages) + goto out; + + cpu_buffer->nr_pages_to_update = nr_pages - + cpu_buffer->nr_pages; + + INIT_LIST_HEAD(&cpu_buffer->new_pages); + if (cpu_buffer->nr_pages_to_update > 0 && + __rb_allocate_pages(cpu_buffer->nr_pages_to_update, + &cpu_buffer->new_pages, cpu_id)) { + err = -ENOMEM; + goto out_err; } - } - for_each_buffer_cpu(buffer, cpu) { - cpu_buffer = buffer->buffers[cpu]; - rb_insert_pages(cpu_buffer, &pages, new_pages); - } + get_online_cpus(); + + preempt_disable(); + /* The update must run on the CPU that is being updated. */ + if (cpu_id == smp_processor_id() || !cpu_online(cpu_id)) + rb_update_pages(cpu_buffer); + else { + /* + * Can not disable preemption for schedule_work_on() + * on PREEMPT_RT. + */ + preempt_enable(); + schedule_work_on(cpu_id, + &cpu_buffer->update_pages_work); + wait_for_completion(&cpu_buffer->update_done); + preempt_disable(); + } + preempt_enable(); - if (RB_WARN_ON(buffer, !list_empty(&pages))) - goto out_fail; + cpu_buffer->nr_pages_to_update = 0; + put_online_cpus(); + } out: - buffer->pages = nr_pages; - put_online_cpus(); - mutex_unlock(&buffer->mutex); + /* + * The ring buffer resize can happen with the ring buffer + * enabled, so that the update disturbs the tracing as little + * as possible. But if the buffer is disabled, we do not need + * to worry about that, and we can take the time to verify + * that the buffer is not corrupt. + */ + if (atomic_read(&buffer->record_disabled)) { + atomic_inc(&buffer->record_disabled); + /* + * Even though the buffer was disabled, we must make sure + * that it is truly disabled before calling rb_check_pages. + * There could have been a race between checking + * record_disable and incrementing it. + */ + synchronize_sched(); + for_each_buffer_cpu(buffer, cpu) { + cpu_buffer = buffer->buffers[cpu]; + rb_check_pages(cpu_buffer); + } + atomic_dec(&buffer->record_disabled); + } + mutex_unlock(&buffer->mutex); return size; - free_pages: - list_for_each_entry_safe(bpage, tmp, &pages, list) { - list_del_init(&bpage->list); - free_buffer_page(bpage); + out_err: + for_each_buffer_cpu(buffer, cpu) { + struct buffer_page *bpage, *tmp; + + cpu_buffer = buffer->buffers[cpu]; + cpu_buffer->nr_pages_to_update = 0; + + if (list_empty(&cpu_buffer->new_pages)) + continue; + + list_for_each_entry_safe(bpage, tmp, &cpu_buffer->new_pages, + list) { + list_del_init(&bpage->list); + free_buffer_page(bpage); + } } - put_online_cpus(); mutex_unlock(&buffer->mutex); - return -ENOMEM; + return err; +} +EXPORT_SYMBOL_GPL(ring_buffer_resize); - /* - * Something went totally wrong, and we are too paranoid - * to even clean up the mess. - */ - out_fail: - put_online_cpus(); +void ring_buffer_change_overwrite(struct ring_buffer *buffer, int val) +{ + mutex_lock(&buffer->mutex); + if (val) + buffer->flags |= RB_FL_OVERWRITE; + else + buffer->flags &= ~RB_FL_OVERWRITE; mutex_unlock(&buffer->mutex); - return -1; } -EXPORT_SYMBOL_GPL(ring_buffer_resize); +EXPORT_SYMBOL_GPL(ring_buffer_change_overwrite); static inline void * __rb_data_page_index(struct buffer_data_page *bpage, unsigned index) @@ -948,29 +1841,17 @@ rb_reader_event(struct ring_buffer_per_cpu *cpu_buffer) } static inline struct ring_buffer_event * -rb_head_event(struct ring_buffer_per_cpu *cpu_buffer) -{ - return __rb_page_index(cpu_buffer->head_page, - cpu_buffer->head_page->read); -} - -static inline struct ring_buffer_event * rb_iter_head_event(struct ring_buffer_iter *iter) { return __rb_page_index(iter->head_page, iter->head); } -static inline unsigned rb_page_write(struct buffer_page *bpage) -{ - return local_read(&bpage->write); -} - static inline unsigned rb_page_commit(struct buffer_page *bpage) { return local_read(&bpage->page->commit); } -/* Size is determined by what has been commited */ +/* Size is determined by what has been committed */ static inline unsigned rb_page_size(struct buffer_page *bpage) { return rb_page_commit(bpage); @@ -982,22 +1863,6 @@ rb_commit_index(struct ring_buffer_per_cpu *cpu_buffer) return rb_page_commit(cpu_buffer->commit_page); } -static inline unsigned rb_head_size(struct ring_buffer_per_cpu *cpu_buffer) -{ - return rb_page_commit(cpu_buffer->head_page); -} - -static inline void rb_inc_page(struct ring_buffer_per_cpu *cpu_buffer, - struct buffer_page **bpage) -{ - struct list_head *p = (*bpage)->list.next; - - if (p == &cpu_buffer->pages) - p = p->next; - - *bpage = list_entry(p, struct buffer_page, list); -} - static inline unsigned rb_event_index(struct ring_buffer_event *event) { @@ -1023,6 +1888,8 @@ rb_event_is_commit(struct ring_buffer_per_cpu *cpu_buffer, static void rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer) { + unsigned long max_count; + /* * We only race with interrupts and NMIs on this CPU. * If we own the commit event, then we can commit @@ -1032,9 +1899,16 @@ rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer) * assign the commit to the tail. */ again: + max_count = cpu_buffer->nr_pages * 100; + while (cpu_buffer->commit_page != cpu_buffer->tail_page) { - cpu_buffer->commit_page->page->commit = - cpu_buffer->commit_page->write; + if (RB_WARN_ON(cpu_buffer, !(--max_count))) + return; + if (RB_WARN_ON(cpu_buffer, + rb_is_reader_page(cpu_buffer->tail_page))) + return; + local_set(&cpu_buffer->commit_page->page->commit, + rb_page_write(cpu_buffer->commit_page)); rb_inc_page(cpu_buffer, &cpu_buffer->commit_page); cpu_buffer->write_stamp = cpu_buffer->commit_page->page->time_stamp; @@ -1043,8 +1917,12 @@ rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer) } while (rb_commit_index(cpu_buffer) != rb_page_write(cpu_buffer->commit_page)) { - cpu_buffer->commit_page->page->commit = - cpu_buffer->commit_page->write; + + local_set(&cpu_buffer->commit_page->page->commit, + rb_page_write(cpu_buffer->commit_page)); + RB_WARN_ON(cpu_buffer, + local_read(&cpu_buffer->commit_page->page->commit) & + ~RB_WRITE_MASK); barrier(); } @@ -1077,7 +1955,7 @@ static void rb_inc_iter(struct ring_buffer_iter *iter) * to the head page instead of next. */ if (iter->head_page == cpu_buffer->reader_page) - iter->head_page = cpu_buffer->head_page; + iter->head_page = rb_set_head_page(cpu_buffer); else rb_inc_page(cpu_buffer, &iter->head_page); @@ -1085,8 +1963,27 @@ static void rb_inc_iter(struct ring_buffer_iter *iter) iter->head = 0; } +/* Slow path, do not inline */ +static noinline struct ring_buffer_event * +rb_add_time_stamp(struct ring_buffer_event *event, u64 delta) +{ + event->type_len = RINGBUF_TYPE_TIME_EXTEND; + + /* Not the first event on the page? */ + if (rb_event_index(event)) { + event->time_delta = delta & TS_MASK; + event->array[0] = delta >> TS_SHIFT; + } else { + /* nope, just zero it */ + event->time_delta = 0; + event->array[0] = 0; + } + + return skip_time_extend(event); +} + /** - * ring_buffer_update_event - update event type and data + * rb_update_event - update event type and data * @event: the even to update * @type: the type of event * @length: the size of the event field in the ring buffer @@ -1097,28 +1994,189 @@ static void rb_inc_iter(struct ring_buffer_iter *iter) * data field. */ static void -rb_update_event(struct ring_buffer_event *event, - unsigned type, unsigned length) +rb_update_event(struct ring_buffer_per_cpu *cpu_buffer, + struct ring_buffer_event *event, unsigned length, + int add_timestamp, u64 delta) { - event->type_len = type; + /* Only a commit updates the timestamp */ + if (unlikely(!rb_event_is_commit(cpu_buffer, event))) + delta = 0; + + /* + * If we need to add a timestamp, then we + * add it to the start of the resevered space. + */ + if (unlikely(add_timestamp)) { + event = rb_add_time_stamp(event, delta); + length -= RB_LEN_TIME_EXTEND; + delta = 0; + } + + event->time_delta = delta; + length -= RB_EVNT_HDR_SIZE; + if (length > RB_MAX_SMALL_DATA || RB_FORCE_8BYTE_ALIGNMENT) { + event->type_len = 0; + event->array[0] = length; + } else + event->type_len = DIV_ROUND_UP(length, RB_ALIGNMENT); +} + +/* + * rb_handle_head_page - writer hit the head page + * + * Returns: +1 to retry page + * 0 to continue + * -1 on error + */ +static int +rb_handle_head_page(struct ring_buffer_per_cpu *cpu_buffer, + struct buffer_page *tail_page, + struct buffer_page *next_page) +{ + struct buffer_page *new_head; + int entries; + int type; + int ret; + + entries = rb_page_entries(next_page); + + /* + * The hard part is here. We need to move the head + * forward, and protect against both readers on + * other CPUs and writers coming in via interrupts. + */ + type = rb_head_page_set_update(cpu_buffer, next_page, tail_page, + RB_PAGE_HEAD); + + /* + * type can be one of four: + * NORMAL - an interrupt already moved it for us + * HEAD - we are the first to get here. + * UPDATE - we are the interrupt interrupting + * a current move. + * MOVED - a reader on another CPU moved the next + * pointer to its reader page. Give up + * and try again. + */ switch (type) { + case RB_PAGE_HEAD: + /* + * We changed the head to UPDATE, thus + * it is our responsibility to update + * the counters. + */ + local_add(entries, &cpu_buffer->overrun); + local_sub(BUF_PAGE_SIZE, &cpu_buffer->entries_bytes); - case RINGBUF_TYPE_PADDING: - case RINGBUF_TYPE_TIME_EXTEND: - case RINGBUF_TYPE_TIME_STAMP: + /* + * The entries will be zeroed out when we move the + * tail page. + */ + + /* still more to do */ break; - case 0: - length -= RB_EVNT_HDR_SIZE; - if (length > RB_MAX_SMALL_DATA) - event->array[0] = length; - else - event->type_len = DIV_ROUND_UP(length, RB_ALIGNMENT); + case RB_PAGE_UPDATE: + /* + * This is an interrupt that interrupt the + * previous update. Still more to do. + */ break; + case RB_PAGE_NORMAL: + /* + * An interrupt came in before the update + * and processed this for us. + * Nothing left to do. + */ + return 1; + case RB_PAGE_MOVED: + /* + * The reader is on another CPU and just did + * a swap with our next_page. + * Try again. + */ + return 1; default: - BUG(); + RB_WARN_ON(cpu_buffer, 1); /* WTF??? */ + return -1; + } + + /* + * Now that we are here, the old head pointer is + * set to UPDATE. This will keep the reader from + * swapping the head page with the reader page. + * The reader (on another CPU) will spin till + * we are finished. + * + * We just need to protect against interrupts + * doing the job. We will set the next pointer + * to HEAD. After that, we set the old pointer + * to NORMAL, but only if it was HEAD before. + * otherwise we are an interrupt, and only + * want the outer most commit to reset it. + */ + new_head = next_page; + rb_inc_page(cpu_buffer, &new_head); + + ret = rb_head_page_set_head(cpu_buffer, new_head, next_page, + RB_PAGE_NORMAL); + + /* + * Valid returns are: + * HEAD - an interrupt came in and already set it. + * NORMAL - One of two things: + * 1) We really set it. + * 2) A bunch of interrupts came in and moved + * the page forward again. + */ + switch (ret) { + case RB_PAGE_HEAD: + case RB_PAGE_NORMAL: + /* OK */ + break; + default: + RB_WARN_ON(cpu_buffer, 1); + return -1; + } + + /* + * It is possible that an interrupt came in, + * set the head up, then more interrupts came in + * and moved it again. When we get back here, + * the page would have been set to NORMAL but we + * just set it back to HEAD. + * + * How do you detect this? Well, if that happened + * the tail page would have moved. + */ + if (ret == RB_PAGE_NORMAL) { + /* + * If the tail had moved passed next, then we need + * to reset the pointer. + */ + if (cpu_buffer->tail_page != tail_page && + cpu_buffer->tail_page != next_page) + rb_head_page_set_normal(cpu_buffer, new_head, + next_page, + RB_PAGE_HEAD); + } + + /* + * If this was the outer most commit (the one that + * changed the original pointer from HEAD to UPDATE), + * then it is up to us to reset it to NORMAL. + */ + if (type == RB_PAGE_HEAD) { + ret = rb_head_page_set_normal(cpu_buffer, next_page, + tail_page, + RB_PAGE_UPDATE); + if (RB_WARN_ON(cpu_buffer, + ret != RB_PAGE_UPDATE)) + return -1; } + + return 0; } static unsigned rb_calculate_event_length(unsigned length) @@ -1129,11 +2187,11 @@ static unsigned rb_calculate_event_length(unsigned length) if (!length) length = 1; - if (length > RB_MAX_SMALL_DATA) + if (length > RB_MAX_SMALL_DATA || RB_FORCE_8BYTE_ALIGNMENT) length += sizeof(event.array[0]); length += RB_EVNT_HDR_SIZE; - length = ALIGN(length, RB_ALIGNMENT); + length = ALIGN(length, RB_ARCH_ALIGNMENT); return length; } @@ -1150,6 +2208,14 @@ rb_reset_tail(struct ring_buffer_per_cpu *cpu_buffer, * must fill the old tail_page with padding. */ if (tail >= BUF_PAGE_SIZE) { + /* + * If the page was filled, then we still need + * to update the real_end. Reset it to zero + * and the reader will ignore it. + */ + if (tail == BUF_PAGE_SIZE) + tail_page->real_end = 0; + local_sub(length, &tail_page->write); return; } @@ -1157,6 +2223,16 @@ rb_reset_tail(struct ring_buffer_per_cpu *cpu_buffer, event = __rb_page_index(tail_page, tail); kmemcheck_annotate_bitfield(event, bitfield); + /* account for padding bytes */ + local_add(BUF_PAGE_SIZE - tail, &cpu_buffer->entries_bytes); + + /* + * Save the original length to the meta data. + * This will be used by the reader to add lost event + * counter. + */ + tail_page->real_end = tail; + /* * If this event is bigger than the minimum size, then * we need to be careful that we don't subtract the @@ -1184,111 +2260,110 @@ rb_reset_tail(struct ring_buffer_per_cpu *cpu_buffer, event->type_len = RINGBUF_TYPE_PADDING; /* time delta must be non zero */ event->time_delta = 1; - /* Account for this as an entry */ - local_inc(&tail_page->entries); - local_inc(&cpu_buffer->entries); /* Set write to end of buffer */ length = (tail + length) - BUF_PAGE_SIZE; local_sub(length, &tail_page->write); } -static struct ring_buffer_event * +/* + * This is the slow path, force gcc not to inline it. + */ +static noinline struct ring_buffer_event * rb_move_tail(struct ring_buffer_per_cpu *cpu_buffer, unsigned long length, unsigned long tail, - struct buffer_page *commit_page, - struct buffer_page *tail_page, u64 *ts) + struct buffer_page *tail_page, u64 ts) { - struct buffer_page *next_page, *head_page, *reader_page; + struct buffer_page *commit_page = cpu_buffer->commit_page; struct ring_buffer *buffer = cpu_buffer->buffer; - bool lock_taken = false; - unsigned long flags; + struct buffer_page *next_page; + int ret; next_page = tail_page; - local_irq_save(flags); - /* - * Since the write to the buffer is still not - * fully lockless, we must be careful with NMIs. - * The locks in the writers are taken when a write - * crosses to a new page. The locks protect against - * races with the readers (this will soon be fixed - * with a lockless solution). - * - * Because we can not protect against NMIs, and we - * want to keep traces reentrant, we need to manage - * what happens when we are in an NMI. - * - * NMIs can happen after we take the lock. - * If we are in an NMI, only take the lock - * if it is not already taken. Otherwise - * simply fail. - */ - if (unlikely(in_nmi())) { - if (!__raw_spin_trylock(&cpu_buffer->lock)) { - cpu_buffer->nmi_dropped++; - goto out_reset; - } - } else - __raw_spin_lock(&cpu_buffer->lock); - - lock_taken = true; - rb_inc_page(cpu_buffer, &next_page); - head_page = cpu_buffer->head_page; - reader_page = cpu_buffer->reader_page; - - /* we grabbed the lock before incrementing */ - if (RB_WARN_ON(cpu_buffer, next_page == reader_page)) - goto out_reset; - /* * If for some reason, we had an interrupt storm that made * it all the way around the buffer, bail, and warn * about it. */ if (unlikely(next_page == commit_page)) { - cpu_buffer->commit_overrun++; + local_inc(&cpu_buffer->commit_overrun); goto out_reset; } - if (next_page == head_page) { - if (!(buffer->flags & RB_FL_OVERWRITE)) - goto out_reset; + /* + * This is where the fun begins! + * + * We are fighting against races between a reader that + * could be on another CPU trying to swap its reader + * page with the buffer head. + * + * We are also fighting against interrupts coming in and + * moving the head or tail on us as well. + * + * If the next page is the head page then we have filled + * the buffer, unless the commit page is still on the + * reader page. + */ + if (rb_is_head_page(cpu_buffer, next_page, &tail_page->list)) { - /* tail_page has not moved yet? */ - if (tail_page == cpu_buffer->tail_page) { - /* count overflows */ - cpu_buffer->overrun += - local_read(&head_page->entries); + /* + * If the commit is not on the reader page, then + * move the header page. + */ + if (!rb_is_reader_page(cpu_buffer->commit_page)) { + /* + * If we are not in overwrite mode, + * this is easy, just stop here. + */ + if (!(buffer->flags & RB_FL_OVERWRITE)) { + local_inc(&cpu_buffer->dropped_events); + goto out_reset; + } - rb_inc_page(cpu_buffer, &head_page); - cpu_buffer->head_page = head_page; - cpu_buffer->head_page->read = 0; + ret = rb_handle_head_page(cpu_buffer, + tail_page, + next_page); + if (ret < 0) + goto out_reset; + if (ret) + goto out_again; + } else { + /* + * We need to be careful here too. The + * commit page could still be on the reader + * page. We could have a small buffer, and + * have filled up the buffer with events + * from interrupts and such, and wrapped. + * + * Note, if the tail page is also the on the + * reader_page, we let it move out. + */ + if (unlikely((cpu_buffer->commit_page != + cpu_buffer->tail_page) && + (cpu_buffer->commit_page == + cpu_buffer->reader_page))) { + local_inc(&cpu_buffer->commit_overrun); + goto out_reset; + } } } - /* - * If the tail page is still the same as what we think - * it is, then it is up to us to update the tail - * pointer. - */ - if (tail_page == cpu_buffer->tail_page) { - local_set(&next_page->write, 0); - local_set(&next_page->entries, 0); - local_set(&next_page->page->commit, 0); - cpu_buffer->tail_page = next_page; - - /* reread the time stamp */ - *ts = rb_time_stamp(buffer, cpu_buffer->cpu); - cpu_buffer->tail_page->page->time_stamp = *ts; + ret = rb_tail_page_update(cpu_buffer, tail_page, next_page); + if (ret) { + /* + * Nested commits always have zero deltas, so + * just reread the time stamp + */ + ts = rb_time_stamp(buffer); + next_page->page->time_stamp = ts; } - rb_reset_tail(cpu_buffer, tail_page, tail, length); + out_again: - __raw_spin_unlock(&cpu_buffer->lock); - local_irq_restore(flags); + rb_reset_tail(cpu_buffer, tail_page, tail, length); /* fail and let the caller try again */ return ERR_PTR(-EAGAIN); @@ -1297,48 +2372,62 @@ rb_move_tail(struct ring_buffer_per_cpu *cpu_buffer, /* reset write */ rb_reset_tail(cpu_buffer, tail_page, tail, length); - if (likely(lock_taken)) - __raw_spin_unlock(&cpu_buffer->lock); - local_irq_restore(flags); return NULL; } static struct ring_buffer_event * __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer, - unsigned type, unsigned long length, u64 *ts) + unsigned long length, u64 ts, + u64 delta, int add_timestamp) { - struct buffer_page *tail_page, *commit_page; + struct buffer_page *tail_page; struct ring_buffer_event *event; unsigned long tail, write; - commit_page = cpu_buffer->commit_page; - /* we just need to protect against interrupts */ - barrier(); + /* + * If the time delta since the last event is too big to + * hold in the time field of the event, then we append a + * TIME EXTEND event ahead of the data event. + */ + if (unlikely(add_timestamp)) + length += RB_LEN_TIME_EXTEND; + tail_page = cpu_buffer->tail_page; write = local_add_return(length, &tail_page->write); + + /* set write to only the index of the write */ + write &= RB_WRITE_MASK; tail = write - length; + /* + * If this is the first commit on the page, then it has the same + * timestamp as the page itself. + */ + if (!tail) + delta = 0; + /* See if we shot pass the end of this buffer page */ - if (write > BUF_PAGE_SIZE) + if (unlikely(write > BUF_PAGE_SIZE)) return rb_move_tail(cpu_buffer, length, tail, - commit_page, tail_page, ts); + tail_page, ts); /* We reserved something on the buffer */ event = __rb_page_index(tail_page, tail); kmemcheck_annotate_bitfield(event, bitfield); - rb_update_event(event, type, length); + rb_update_event(cpu_buffer, event, length, add_timestamp, delta); - /* The passed in type is zero for DATA */ - if (likely(!type)) - local_inc(&tail_page->entries); + local_inc(&tail_page->entries); /* * If this is the first commit on the page, then update * its timestamp. */ if (!tail) - tail_page->page->time_stamp = *ts; + tail_page->page->time_stamp = ts; + + /* account for these added bytes */ + local_add(length, &cpu_buffer->entries_bytes); return event; } @@ -1353,102 +2442,43 @@ rb_try_to_discard(struct ring_buffer_per_cpu *cpu_buffer, unsigned long addr; new_index = rb_event_index(event); - old_index = new_index + rb_event_length(event); + old_index = new_index + rb_event_ts_length(event); addr = (unsigned long)event; addr &= PAGE_MASK; bpage = cpu_buffer->tail_page; if (bpage->page == (void *)addr && rb_page_write(bpage) == old_index) { + unsigned long write_mask = + local_read(&bpage->write) & ~RB_WRITE_MASK; + unsigned long event_length = rb_event_length(event); /* * This is on the tail page. It is possible that * a write could come in and move the tail page * and write to the next page. That is fine * because we just shorten what is on this page. */ + old_index += write_mask; + new_index += write_mask; index = local_cmpxchg(&bpage->write, old_index, new_index); - if (index == old_index) + if (index == old_index) { + /* update counters */ + local_sub(event_length, &cpu_buffer->entries_bytes); return 1; + } } /* could not discard */ return 0; } -static int -rb_add_time_stamp(struct ring_buffer_per_cpu *cpu_buffer, - u64 *ts, u64 *delta) -{ - struct ring_buffer_event *event; - static int once; - int ret; - - if (unlikely(*delta > (1ULL << 59) && !once++)) { - printk(KERN_WARNING "Delta way too big! %llu" - " ts=%llu write stamp = %llu\n", - (unsigned long long)*delta, - (unsigned long long)*ts, - (unsigned long long)cpu_buffer->write_stamp); - WARN_ON(1); - } - - /* - * The delta is too big, we to add a - * new timestamp. - */ - event = __rb_reserve_next(cpu_buffer, - RINGBUF_TYPE_TIME_EXTEND, - RB_LEN_TIME_EXTEND, - ts); - if (!event) - return -EBUSY; - - if (PTR_ERR(event) == -EAGAIN) - return -EAGAIN; - - /* Only a commited time event can update the write stamp */ - if (rb_event_is_commit(cpu_buffer, event)) { - /* - * If this is the first on the page, then it was - * updated with the page itself. Try to discard it - * and if we can't just make it zero. - */ - if (rb_event_index(event)) { - event->time_delta = *delta & TS_MASK; - event->array[0] = *delta >> TS_SHIFT; - } else { - /* try to discard, since we do not need this */ - if (!rb_try_to_discard(cpu_buffer, event)) { - /* nope, just zero it */ - event->time_delta = 0; - event->array[0] = 0; - } - } - cpu_buffer->write_stamp = *ts; - /* let the caller know this was the commit */ - ret = 1; - } else { - /* Try to discard the event */ - if (!rb_try_to_discard(cpu_buffer, event)) { - /* Darn, this is just wasted space */ - event->time_delta = 0; - event->array[0] = 0; - } - ret = 0; - } - - *delta = 0; - - return ret; -} - static void rb_start_commit(struct ring_buffer_per_cpu *cpu_buffer) { local_inc(&cpu_buffer->committing); local_inc(&cpu_buffer->commits); } -static void rb_end_commit(struct ring_buffer_per_cpu *cpu_buffer) +static inline void rb_end_commit(struct ring_buffer_per_cpu *cpu_buffer) { unsigned long commits; @@ -1481,18 +2511,38 @@ static void rb_end_commit(struct ring_buffer_per_cpu *cpu_buffer) } static struct ring_buffer_event * -rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer, +rb_reserve_next_event(struct ring_buffer *buffer, + struct ring_buffer_per_cpu *cpu_buffer, unsigned long length) { struct ring_buffer_event *event; - u64 ts, delta = 0; - int commit = 0; + u64 ts, delta; int nr_loops = 0; + int add_timestamp; + u64 diff; rb_start_commit(cpu_buffer); +#ifdef CONFIG_RING_BUFFER_ALLOW_SWAP + /* + * Due to the ability to swap a cpu buffer from a buffer + * it is possible it was swapped before we committed. + * (committing stops a swap). We check for it here and + * if it happened, we have to fail the write. + */ + barrier(); + if (unlikely(ACCESS_ONCE(cpu_buffer->buffer) != buffer)) { + local_dec(&cpu_buffer->committing); + local_dec(&cpu_buffer->commits); + return NULL; + } +#endif + length = rb_calculate_event_length(length); again: + add_timestamp = 0; + delta = 0; + /* * We allow for interrupts to reenter here and do a trace. * If one does, it will cause this original code to loop @@ -1505,57 +2555,41 @@ rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer, if (RB_WARN_ON(cpu_buffer, ++nr_loops > 1000)) goto out_fail; - ts = rb_time_stamp(cpu_buffer->buffer, cpu_buffer->cpu); - - /* - * Only the first commit can update the timestamp. - * Yes there is a race here. If an interrupt comes in - * just after the conditional and it traces too, then it - * will also check the deltas. More than one timestamp may - * also be made. But only the entry that did the actual - * commit will be something other than zero. - */ - if (likely(cpu_buffer->tail_page == cpu_buffer->commit_page && - rb_page_write(cpu_buffer->tail_page) == - rb_commit_index(cpu_buffer))) { - u64 diff; - - diff = ts - cpu_buffer->write_stamp; + ts = rb_time_stamp(cpu_buffer->buffer); + diff = ts - cpu_buffer->write_stamp; - /* make sure this diff is calculated here */ - barrier(); - - /* Did the write stamp get updated already? */ - if (unlikely(ts < cpu_buffer->write_stamp)) - goto get_event; + /* make sure this diff is calculated here */ + barrier(); + /* Did the write stamp get updated already? */ + if (likely(ts >= cpu_buffer->write_stamp)) { delta = diff; if (unlikely(test_time_stamp(delta))) { - - commit = rb_add_time_stamp(cpu_buffer, &ts, &delta); - if (commit == -EBUSY) - goto out_fail; - - if (commit == -EAGAIN) - goto again; - - RB_WARN_ON(cpu_buffer, commit < 0); + int local_clock_stable = 1; +#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK + local_clock_stable = sched_clock_stable(); +#endif + WARN_ONCE(delta > (1ULL << 59), + KERN_WARNING "Delta way too big! %llu ts=%llu write stamp = %llu\n%s", + (unsigned long long)delta, + (unsigned long long)ts, + (unsigned long long)cpu_buffer->write_stamp, + local_clock_stable ? "" : + "If you just came from a suspend/resume,\n" + "please switch to the trace global clock:\n" + " echo global > /sys/kernel/debug/tracing/trace_clock\n"); + add_timestamp = 1; } } - get_event: - event = __rb_reserve_next(cpu_buffer, 0, length, &ts); + event = __rb_reserve_next(cpu_buffer, length, ts, + delta, add_timestamp); if (unlikely(PTR_ERR(event) == -EAGAIN)) goto again; if (!event) goto out_fail; - if (!rb_event_is_commit(cpu_buffer, event)) - delta = 0; - - event->time_delta = delta; - return event; out_fail: @@ -1565,34 +2599,76 @@ rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer, #ifdef CONFIG_TRACING -#define TRACE_RECURSIVE_DEPTH 16 +/* + * The lock and unlock are done within a preempt disable section. + * The current_context per_cpu variable can only be modified + * by the current task between lock and unlock. But it can + * be modified more than once via an interrupt. To pass this + * information from the lock to the unlock without having to + * access the 'in_interrupt()' functions again (which do show + * a bit of overhead in something as critical as function tracing, + * we use a bitmask trick. + * + * bit 0 = NMI context + * bit 1 = IRQ context + * bit 2 = SoftIRQ context + * bit 3 = normal context. + * + * This works because this is the order of contexts that can + * preempt other contexts. A SoftIRQ never preempts an IRQ + * context. + * + * When the context is determined, the corresponding bit is + * checked and set (if it was set, then a recursion of that context + * happened). + * + * On unlock, we need to clear this bit. To do so, just subtract + * 1 from the current_context and AND it to itself. + * + * (binary) + * 101 - 1 = 100 + * 101 & 100 = 100 (clearing bit zero) + * + * 1010 - 1 = 1001 + * 1010 & 1001 = 1000 (clearing bit 1) + * + * The least significant bit can be cleared this way, and it + * just so happens that it is the same bit corresponding to + * the current context. + */ +static DEFINE_PER_CPU(unsigned int, current_context); -static int trace_recursive_lock(void) +static __always_inline int trace_recursive_lock(void) { - current->trace_recursion++; - - if (likely(current->trace_recursion < TRACE_RECURSIVE_DEPTH)) - return 0; + unsigned int val = this_cpu_read(current_context); + int bit; + + if (in_interrupt()) { + if (in_nmi()) + bit = 0; + else if (in_irq()) + bit = 1; + else + bit = 2; + } else + bit = 3; - /* Disable all tracing before we do anything else */ - tracing_off_permanent(); + if (unlikely(val & (1 << bit))) + return 1; - printk_once(KERN_WARNING "Tracing recursion: depth[%ld]:" - "HC[%lu]:SC[%lu]:NMI[%lu]\n", - current->trace_recursion, - hardirq_count() >> HARDIRQ_SHIFT, - softirq_count() >> SOFTIRQ_SHIFT, - in_nmi()); + val |= (1 << bit); + this_cpu_write(current_context, val); - WARN_ON_ONCE(1); - return -1; + return 0; } -static void trace_recursive_unlock(void) +static __always_inline void trace_recursive_unlock(void) { - WARN_ON_ONCE(!current->trace_recursion); + unsigned int val = this_cpu_read(current_context); - current->trace_recursion--; + val--; + val &= this_cpu_read(current_context); + this_cpu_write(current_context, val); } #else @@ -1602,8 +2678,6 @@ static void trace_recursive_unlock(void) #endif -static DEFINE_PER_CPU(int, rb_need_resched); - /** * ring_buffer_lock_reserve - reserve a part of the buffer * @buffer: the ring buffer to reserve from @@ -1624,16 +2698,16 @@ ring_buffer_lock_reserve(struct ring_buffer *buffer, unsigned long length) { struct ring_buffer_per_cpu *cpu_buffer; struct ring_buffer_event *event; - int cpu, resched; + int cpu; if (ring_buffer_flags != RB_BUFFERS_ON) return NULL; - if (atomic_read(&buffer->record_disabled)) - return NULL; - /* If we are tracing schedule, we don't want to recurse */ - resched = ftrace_preempt_disable(); + preempt_disable_notrace(); + + if (atomic_read(&buffer->record_disabled)) + goto out_nocheck; if (trace_recursive_lock()) goto out_nocheck; @@ -1651,44 +2725,73 @@ ring_buffer_lock_reserve(struct ring_buffer *buffer, unsigned long length) if (length > BUF_MAX_DATA_SIZE) goto out; - event = rb_reserve_next_event(cpu_buffer, length); + event = rb_reserve_next_event(buffer, cpu_buffer, length); if (!event) goto out; - /* - * Need to store resched state on this cpu. - * Only the first needs to. - */ - - if (preempt_count() == 1) - per_cpu(rb_need_resched, cpu) = resched; - return event; out: trace_recursive_unlock(); out_nocheck: - ftrace_preempt_enable(resched); + preempt_enable_notrace(); return NULL; } EXPORT_SYMBOL_GPL(ring_buffer_lock_reserve); -static void rb_commit(struct ring_buffer_per_cpu *cpu_buffer, +static void +rb_update_write_stamp(struct ring_buffer_per_cpu *cpu_buffer, struct ring_buffer_event *event) { - local_inc(&cpu_buffer->entries); + u64 delta; /* * The event first in the commit queue updates the * time stamp. */ - if (rb_event_is_commit(cpu_buffer, event)) - cpu_buffer->write_stamp += event->time_delta; + if (rb_event_is_commit(cpu_buffer, event)) { + /* + * A commit event that is first on a page + * updates the write timestamp with the page stamp + */ + if (!rb_event_index(event)) + cpu_buffer->write_stamp = + cpu_buffer->commit_page->page->time_stamp; + else if (event->type_len == RINGBUF_TYPE_TIME_EXTEND) { + delta = event->array[0]; + delta <<= TS_SHIFT; + delta += event->time_delta; + cpu_buffer->write_stamp += delta; + } else + cpu_buffer->write_stamp += event->time_delta; + } +} +static void rb_commit(struct ring_buffer_per_cpu *cpu_buffer, + struct ring_buffer_event *event) +{ + local_inc(&cpu_buffer->entries); + rb_update_write_stamp(cpu_buffer, event); rb_end_commit(cpu_buffer); } +static __always_inline void +rb_wakeups(struct ring_buffer *buffer, struct ring_buffer_per_cpu *cpu_buffer) +{ + if (buffer->irq_work.waiters_pending) { + buffer->irq_work.waiters_pending = false; + /* irq_work_queue() supplies it's own memory barriers */ + irq_work_queue(&buffer->irq_work.work); + } + + if (cpu_buffer->irq_work.waiters_pending) { + cpu_buffer->irq_work.waiters_pending = false; + /* irq_work_queue() supplies it's own memory barriers */ + irq_work_queue(&cpu_buffer->irq_work.work); + } +} + /** * ring_buffer_unlock_commit - commit a reserved * @buffer: The buffer to commit to @@ -1708,15 +2811,11 @@ int ring_buffer_unlock_commit(struct ring_buffer *buffer, rb_commit(cpu_buffer, event); + rb_wakeups(buffer, cpu_buffer); + trace_recursive_unlock(); - /* - * Only the last preempt count needs to restore preemption. - */ - if (preempt_count() == 1) - ftrace_preempt_enable(per_cpu(rb_need_resched, cpu)); - else - preempt_enable_no_resched_notrace(); + preempt_enable_notrace(); return 0; } @@ -1724,6 +2823,9 @@ EXPORT_SYMBOL_GPL(ring_buffer_unlock_commit); static inline void rb_event_discard(struct ring_buffer_event *event) { + if (event->type_len == RINGBUF_TYPE_TIME_EXTEND) + event = skip_time_extend(event); + /* array[0] holds the actual length for the discarded event */ event->array[0] = rb_event_data_length(event) - RB_EVNT_HDR_SIZE; event->type_len = RINGBUF_TYPE_PADDING; @@ -1732,32 +2834,57 @@ static inline void rb_event_discard(struct ring_buffer_event *event) event->time_delta = 1; } -/** - * ring_buffer_event_discard - discard any event in the ring buffer - * @event: the event to discard - * - * Sometimes a event that is in the ring buffer needs to be ignored. - * This function lets the user discard an event in the ring buffer - * and then that event will not be read later. - * - * Note, it is up to the user to be careful with this, and protect - * against races. If the user discards an event that has been consumed - * it is possible that it could corrupt the ring buffer. +/* + * Decrement the entries to the page that an event is on. + * The event does not even need to exist, only the pointer + * to the page it is on. This may only be called before the commit + * takes place. */ -void ring_buffer_event_discard(struct ring_buffer_event *event) +static inline void +rb_decrement_entry(struct ring_buffer_per_cpu *cpu_buffer, + struct ring_buffer_event *event) { - rb_event_discard(event); + unsigned long addr = (unsigned long)event; + struct buffer_page *bpage = cpu_buffer->commit_page; + struct buffer_page *start; + + addr &= PAGE_MASK; + + /* Do the likely case first */ + if (likely(bpage->page == (void *)addr)) { + local_dec(&bpage->entries); + return; + } + + /* + * Because the commit page may be on the reader page we + * start with the next page and check the end loop there. + */ + rb_inc_page(cpu_buffer, &bpage); + start = bpage; + do { + if (bpage->page == (void *)addr) { + local_dec(&bpage->entries); + return; + } + rb_inc_page(cpu_buffer, &bpage); + } while (bpage != start); + + /* commit not part of this buffer?? */ + RB_WARN_ON(cpu_buffer, 1); } -EXPORT_SYMBOL_GPL(ring_buffer_event_discard); /** * ring_buffer_commit_discard - discard an event that has not been committed * @buffer: the ring buffer * @event: non committed event to discard * - * This is similar to ring_buffer_event_discard but must only be - * performed on an event that has not been committed yet. The difference - * is that this will also try to free the event from the ring buffer + * Sometimes an event that is in the ring buffer needs to be ignored. + * This function lets the user discard an event in the ring buffer + * and then that event will not be read later. + * + * This function only works if it is called before the the item has been + * committed. It will try to free the event from the ring buffer * if another event has not been added behind it. * * If another event has been added behind it, it will set the event @@ -1785,26 +2912,21 @@ void ring_buffer_discard_commit(struct ring_buffer *buffer, */ RB_WARN_ON(buffer, !local_read(&cpu_buffer->committing)); - if (!rb_try_to_discard(cpu_buffer, event)) + rb_decrement_entry(cpu_buffer, event); + if (rb_try_to_discard(cpu_buffer, event)) goto out; /* * The commit is still visible by the reader, so we - * must increment entries. + * must still update the timestamp. */ - local_inc(&cpu_buffer->entries); + rb_update_write_stamp(cpu_buffer, event); out: rb_end_commit(cpu_buffer); trace_recursive_unlock(); - /* - * Only the last preempt count needs to restore preemption. - */ - if (preempt_count() == 1) - ftrace_preempt_enable(per_cpu(rb_need_resched, cpu)); - else - preempt_enable_no_resched_notrace(); + preempt_enable_notrace(); } EXPORT_SYMBOL_GPL(ring_buffer_discard_commit); @@ -1823,22 +2945,22 @@ EXPORT_SYMBOL_GPL(ring_buffer_discard_commit); * and not the length of the event which would hold the header. */ int ring_buffer_write(struct ring_buffer *buffer, - unsigned long length, - void *data) + unsigned long length, + void *data) { struct ring_buffer_per_cpu *cpu_buffer; struct ring_buffer_event *event; void *body; int ret = -EBUSY; - int cpu, resched; + int cpu; if (ring_buffer_flags != RB_BUFFERS_ON) return -EBUSY; - if (atomic_read(&buffer->record_disabled)) - return -EBUSY; + preempt_disable_notrace(); - resched = ftrace_preempt_disable(); + if (atomic_read(&buffer->record_disabled)) + goto out; cpu = raw_smp_processor_id(); @@ -1853,7 +2975,7 @@ int ring_buffer_write(struct ring_buffer *buffer, if (length > BUF_MAX_DATA_SIZE) goto out; - event = rb_reserve_next_event(cpu_buffer, length); + event = rb_reserve_next_event(buffer, cpu_buffer, length); if (!event) goto out; @@ -1863,9 +2985,11 @@ int ring_buffer_write(struct ring_buffer *buffer, rb_commit(cpu_buffer, event); + rb_wakeups(buffer, cpu_buffer); + ret = 0; out: - ftrace_preempt_enable(resched); + preempt_enable_notrace(); return ret; } @@ -1874,9 +2998,13 @@ EXPORT_SYMBOL_GPL(ring_buffer_write); static int rb_per_cpu_empty(struct ring_buffer_per_cpu *cpu_buffer) { struct buffer_page *reader = cpu_buffer->reader_page; - struct buffer_page *head = cpu_buffer->head_page; + struct buffer_page *head = rb_set_head_page(cpu_buffer); struct buffer_page *commit = cpu_buffer->commit_page; + /* In case of error, head will be NULL */ + if (unlikely(!head)) + return 1; + return reader->read == rb_page_commit(reader) && (commit == reader || (commit == head && @@ -1903,7 +3031,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_record_disable); * @buffer: The ring buffer to enable writes * * Note, multiple disables will need the same number of enables - * to truely enable the writing (much like preempt_disable). + * to truly enable the writing (much like preempt_disable). */ void ring_buffer_record_enable(struct ring_buffer *buffer) { @@ -1912,6 +3040,63 @@ void ring_buffer_record_enable(struct ring_buffer *buffer) EXPORT_SYMBOL_GPL(ring_buffer_record_enable); /** + * ring_buffer_record_off - stop all writes into the buffer + * @buffer: The ring buffer to stop writes to. + * + * This prevents all writes to the buffer. Any attempt to write + * to the buffer after this will fail and return NULL. + * + * This is different than ring_buffer_record_disable() as + * it works like an on/off switch, where as the disable() version + * must be paired with a enable(). + */ +void ring_buffer_record_off(struct ring_buffer *buffer) +{ + unsigned int rd; + unsigned int new_rd; + + do { + rd = atomic_read(&buffer->record_disabled); + new_rd = rd | RB_BUFFER_OFF; + } while (atomic_cmpxchg(&buffer->record_disabled, rd, new_rd) != rd); +} +EXPORT_SYMBOL_GPL(ring_buffer_record_off); + +/** + * ring_buffer_record_on - restart writes into the buffer + * @buffer: The ring buffer to start writes to. + * + * This enables all writes to the buffer that was disabled by + * ring_buffer_record_off(). + * + * This is different than ring_buffer_record_enable() as + * it works like an on/off switch, where as the enable() version + * must be paired with a disable(). + */ +void ring_buffer_record_on(struct ring_buffer *buffer) +{ + unsigned int rd; + unsigned int new_rd; + + do { + rd = atomic_read(&buffer->record_disabled); + new_rd = rd & ~RB_BUFFER_OFF; + } while (atomic_cmpxchg(&buffer->record_disabled, rd, new_rd) != rd); +} +EXPORT_SYMBOL_GPL(ring_buffer_record_on); + +/** + * ring_buffer_record_is_on - return true if the ring buffer can write + * @buffer: The ring buffer to see if write is enabled + * + * Returns true if the ring buffer is in a state that it accepts writes. + */ +int ring_buffer_record_is_on(struct ring_buffer *buffer) +{ + return !atomic_read(&buffer->record_disabled); +} + +/** * ring_buffer_record_disable_cpu - stop all writes into the cpu_buffer * @buffer: The ring buffer to stop writes to. * @cpu: The CPU buffer to stop @@ -1939,7 +3124,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_record_disable_cpu); * @cpu: The CPU to enable. * * Note, multiple disables will need the same number of enables - * to truely enable the writing (much like preempt_disable). + * to truly enable the writing (much like preempt_disable). */ void ring_buffer_record_enable_cpu(struct ring_buffer *buffer, int cpu) { @@ -1953,6 +3138,72 @@ void ring_buffer_record_enable_cpu(struct ring_buffer *buffer, int cpu) } EXPORT_SYMBOL_GPL(ring_buffer_record_enable_cpu); +/* + * The total entries in the ring buffer is the running counter + * of entries entered into the ring buffer, minus the sum of + * the entries read from the ring buffer and the number of + * entries that were overwritten. + */ +static inline unsigned long +rb_num_of_entries(struct ring_buffer_per_cpu *cpu_buffer) +{ + return local_read(&cpu_buffer->entries) - + (local_read(&cpu_buffer->overrun) + cpu_buffer->read); +} + +/** + * ring_buffer_oldest_event_ts - get the oldest event timestamp from the buffer + * @buffer: The ring buffer + * @cpu: The per CPU buffer to read from. + */ +u64 ring_buffer_oldest_event_ts(struct ring_buffer *buffer, int cpu) +{ + unsigned long flags; + struct ring_buffer_per_cpu *cpu_buffer; + struct buffer_page *bpage; + u64 ret = 0; + + if (!cpumask_test_cpu(cpu, buffer->cpumask)) + return 0; + + cpu_buffer = buffer->buffers[cpu]; + raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags); + /* + * if the tail is on reader_page, oldest time stamp is on the reader + * page + */ + if (cpu_buffer->tail_page == cpu_buffer->reader_page) + bpage = cpu_buffer->reader_page; + else + bpage = rb_set_head_page(cpu_buffer); + if (bpage) + ret = bpage->page->time_stamp; + raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); + + return ret; +} +EXPORT_SYMBOL_GPL(ring_buffer_oldest_event_ts); + +/** + * ring_buffer_bytes_cpu - get the number of bytes consumed in a cpu buffer + * @buffer: The ring buffer + * @cpu: The per CPU buffer to read from. + */ +unsigned long ring_buffer_bytes_cpu(struct ring_buffer *buffer, int cpu) +{ + struct ring_buffer_per_cpu *cpu_buffer; + unsigned long ret; + + if (!cpumask_test_cpu(cpu, buffer->cpumask)) + return 0; + + cpu_buffer = buffer->buffers[cpu]; + ret = local_read(&cpu_buffer->entries_bytes) - cpu_buffer->read_bytes; + + return ret; +} +EXPORT_SYMBOL_GPL(ring_buffer_bytes_cpu); + /** * ring_buffer_entries_cpu - get the number of entries in a cpu buffer * @buffer: The ring buffer @@ -1961,21 +3212,19 @@ EXPORT_SYMBOL_GPL(ring_buffer_record_enable_cpu); unsigned long ring_buffer_entries_cpu(struct ring_buffer *buffer, int cpu) { struct ring_buffer_per_cpu *cpu_buffer; - unsigned long ret; if (!cpumask_test_cpu(cpu, buffer->cpumask)) return 0; cpu_buffer = buffer->buffers[cpu]; - ret = (local_read(&cpu_buffer->entries) - cpu_buffer->overrun) - - cpu_buffer->read; - return ret; + return rb_num_of_entries(cpu_buffer); } EXPORT_SYMBOL_GPL(ring_buffer_entries_cpu); /** - * ring_buffer_overrun_cpu - get the number of overruns in a cpu_buffer + * ring_buffer_overrun_cpu - get the number of overruns caused by the ring + * buffer wrapping around (only if RB_FL_OVERWRITE is on). * @buffer: The ring buffer * @cpu: The per CPU buffer to get the number of overruns from */ @@ -1988,18 +3237,21 @@ unsigned long ring_buffer_overrun_cpu(struct ring_buffer *buffer, int cpu) return 0; cpu_buffer = buffer->buffers[cpu]; - ret = cpu_buffer->overrun; + ret = local_read(&cpu_buffer->overrun); return ret; } EXPORT_SYMBOL_GPL(ring_buffer_overrun_cpu); /** - * ring_buffer_nmi_dropped_cpu - get the number of nmis that were dropped + * ring_buffer_commit_overrun_cpu - get the number of overruns caused by + * commits failing due to the buffer wrapping around while there are uncommitted + * events, such as during an interrupt storm. * @buffer: The ring buffer * @cpu: The per CPU buffer to get the number of overruns from */ -unsigned long ring_buffer_nmi_dropped_cpu(struct ring_buffer *buffer, int cpu) +unsigned long +ring_buffer_commit_overrun_cpu(struct ring_buffer *buffer, int cpu) { struct ring_buffer_per_cpu *cpu_buffer; unsigned long ret; @@ -2008,19 +3260,20 @@ unsigned long ring_buffer_nmi_dropped_cpu(struct ring_buffer *buffer, int cpu) return 0; cpu_buffer = buffer->buffers[cpu]; - ret = cpu_buffer->nmi_dropped; + ret = local_read(&cpu_buffer->commit_overrun); return ret; } -EXPORT_SYMBOL_GPL(ring_buffer_nmi_dropped_cpu); +EXPORT_SYMBOL_GPL(ring_buffer_commit_overrun_cpu); /** - * ring_buffer_commit_overrun_cpu - get the number of overruns caused by commits + * ring_buffer_dropped_events_cpu - get the number of dropped events caused by + * the ring buffer filling up (only if RB_FL_OVERWRITE is off). * @buffer: The ring buffer * @cpu: The per CPU buffer to get the number of overruns from */ unsigned long -ring_buffer_commit_overrun_cpu(struct ring_buffer *buffer, int cpu) +ring_buffer_dropped_events_cpu(struct ring_buffer *buffer, int cpu) { struct ring_buffer_per_cpu *cpu_buffer; unsigned long ret; @@ -2029,11 +3282,29 @@ ring_buffer_commit_overrun_cpu(struct ring_buffer *buffer, int cpu) return 0; cpu_buffer = buffer->buffers[cpu]; - ret = cpu_buffer->commit_overrun; + ret = local_read(&cpu_buffer->dropped_events); return ret; } -EXPORT_SYMBOL_GPL(ring_buffer_commit_overrun_cpu); +EXPORT_SYMBOL_GPL(ring_buffer_dropped_events_cpu); + +/** + * ring_buffer_read_events_cpu - get the number of events successfully read + * @buffer: The ring buffer + * @cpu: The per CPU buffer to get the number of events read + */ +unsigned long +ring_buffer_read_events_cpu(struct ring_buffer *buffer, int cpu) +{ + struct ring_buffer_per_cpu *cpu_buffer; + + if (!cpumask_test_cpu(cpu, buffer->cpumask)) + return 0; + + cpu_buffer = buffer->buffers[cpu]; + return cpu_buffer->read; +} +EXPORT_SYMBOL_GPL(ring_buffer_read_events_cpu); /** * ring_buffer_entries - get the number of entries in a buffer @@ -2051,8 +3322,7 @@ unsigned long ring_buffer_entries(struct ring_buffer *buffer) /* if you care about this being correct, lock the buffer */ for_each_buffer_cpu(buffer, cpu) { cpu_buffer = buffer->buffers[cpu]; - entries += (local_read(&cpu_buffer->entries) - - cpu_buffer->overrun) - cpu_buffer->read; + entries += rb_num_of_entries(cpu_buffer); } return entries; @@ -2060,7 +3330,7 @@ unsigned long ring_buffer_entries(struct ring_buffer *buffer) EXPORT_SYMBOL_GPL(ring_buffer_entries); /** - * ring_buffer_overrun_cpu - get the number of overruns in buffer + * ring_buffer_overruns - get the number of overruns in buffer * @buffer: The ring buffer * * Returns the total number of overruns in the ring buffer @@ -2075,7 +3345,7 @@ unsigned long ring_buffer_overruns(struct ring_buffer *buffer) /* if you care about this being correct, lock the buffer */ for_each_buffer_cpu(buffer, cpu) { cpu_buffer = buffer->buffers[cpu]; - overruns += cpu_buffer->overrun; + overruns += local_read(&cpu_buffer->overrun); } return overruns; @@ -2088,8 +3358,10 @@ static void rb_iter_reset(struct ring_buffer_iter *iter) /* Iterator usage is expected to have record disabled */ if (list_empty(&cpu_buffer->reader_page->list)) { - iter->head_page = cpu_buffer->head_page; - iter->head = cpu_buffer->head_page->read; + iter->head_page = rb_set_head_page(cpu_buffer); + if (unlikely(!iter->head_page)) + return; + iter->head = iter->head_page->read; } else { iter->head_page = cpu_buffer->reader_page; iter->head = cpu_buffer->reader_page->read; @@ -2098,6 +3370,8 @@ static void rb_iter_reset(struct ring_buffer_iter *iter) iter->read_stamp = cpu_buffer->read_stamp; else iter->read_stamp = iter->head_page->page->time_stamp; + iter->cache_reader_page = cpu_buffer->reader_page; + iter->cache_read = cpu_buffer->read; } /** @@ -2117,9 +3391,9 @@ void ring_buffer_iter_reset(struct ring_buffer_iter *iter) cpu_buffer = iter->cpu_buffer; - spin_lock_irqsave(&cpu_buffer->reader_lock, flags); + raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags); rb_iter_reset(iter); - spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); + raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); } EXPORT_SYMBOL_GPL(ring_buffer_iter_reset); @@ -2204,11 +3478,13 @@ static struct buffer_page * rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer) { struct buffer_page *reader = NULL; + unsigned long overwrite; unsigned long flags; int nr_loops = 0; + int ret; local_irq_save(flags); - __raw_spin_lock(&cpu_buffer->lock); + arch_spin_lock(&cpu_buffer->lock); again: /* @@ -2238,40 +3514,90 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer) if (cpu_buffer->commit_page == cpu_buffer->reader_page) goto out; + /* Don't bother swapping if the ring buffer is empty */ + if (rb_num_of_entries(cpu_buffer) == 0) + goto out; + /* - * Splice the empty reader page into the list around the head. * Reset the reader page to size zero. */ - - reader = cpu_buffer->head_page; - cpu_buffer->reader_page->list.next = reader->list.next; - cpu_buffer->reader_page->list.prev = reader->list.prev; - local_set(&cpu_buffer->reader_page->write, 0); local_set(&cpu_buffer->reader_page->entries, 0); local_set(&cpu_buffer->reader_page->page->commit, 0); + cpu_buffer->reader_page->real_end = 0; - /* Make the reader page now replace the head */ - reader->list.prev->next = &cpu_buffer->reader_page->list; - reader->list.next->prev = &cpu_buffer->reader_page->list; + spin: + /* + * Splice the empty reader page into the list around the head. + */ + reader = rb_set_head_page(cpu_buffer); + if (!reader) + goto out; + cpu_buffer->reader_page->list.next = rb_list_head(reader->list.next); + cpu_buffer->reader_page->list.prev = reader->list.prev; + + /* + * cpu_buffer->pages just needs to point to the buffer, it + * has no specific buffer page to point to. Lets move it out + * of our way so we don't accidentally swap it. + */ + cpu_buffer->pages = reader->list.prev; + + /* The reader page will be pointing to the new head */ + rb_set_list_to_head(cpu_buffer, &cpu_buffer->reader_page->list); /* - * If the tail is on the reader, then we must set the head - * to the inserted page, otherwise we set it one before. + * We want to make sure we read the overruns after we set up our + * pointers to the next object. The writer side does a + * cmpxchg to cross pages which acts as the mb on the writer + * side. Note, the reader will constantly fail the swap + * while the writer is updating the pointers, so this + * guarantees that the overwrite recorded here is the one we + * want to compare with the last_overrun. + */ + smp_mb(); + overwrite = local_read(&(cpu_buffer->overrun)); + + /* + * Here's the tricky part. + * + * We need to move the pointer past the header page. + * But we can only do that if a writer is not currently + * moving it. The page before the header page has the + * flag bit '1' set if it is pointing to the page we want. + * but if the writer is in the process of moving it + * than it will be '2' or already moved '0'. */ - cpu_buffer->head_page = cpu_buffer->reader_page; - if (cpu_buffer->commit_page != reader) - rb_inc_page(cpu_buffer, &cpu_buffer->head_page); + ret = rb_head_page_replace(reader, cpu_buffer->reader_page); + + /* + * If we did not convert it, then we must try again. + */ + if (!ret) + goto spin; + + /* + * Yeah! We succeeded in replacing the page. + * + * Now make the new head point back to the reader page. + */ + rb_list_head(reader->list.next)->prev = &cpu_buffer->reader_page->list; + rb_inc_page(cpu_buffer, &cpu_buffer->head_page); /* Finally update the reader page to the new head */ cpu_buffer->reader_page = reader; rb_reset_reader_page(cpu_buffer); + if (overwrite != cpu_buffer->last_overrun) { + cpu_buffer->lost_events = overwrite - cpu_buffer->last_overrun; + cpu_buffer->last_overrun = overwrite; + } + goto again; out: - __raw_spin_unlock(&cpu_buffer->lock); + arch_spin_unlock(&cpu_buffer->lock); local_irq_restore(flags); return reader; @@ -2291,8 +3617,7 @@ static void rb_advance_reader(struct ring_buffer_per_cpu *cpu_buffer) event = rb_reader_event(cpu_buffer); - if (event->type_len <= RINGBUF_TYPE_DATA_TYPE_LEN_MAX - || rb_discarded_event(event)) + if (event->type_len <= RINGBUF_TYPE_DATA_TYPE_LEN_MAX) cpu_buffer->read++; rb_update_read_stamp(cpu_buffer, event); @@ -2303,13 +3628,11 @@ static void rb_advance_reader(struct ring_buffer_per_cpu *cpu_buffer) static void rb_advance_iter(struct ring_buffer_iter *iter) { - struct ring_buffer *buffer; struct ring_buffer_per_cpu *cpu_buffer; struct ring_buffer_event *event; unsigned length; cpu_buffer = iter->cpu_buffer; - buffer = cpu_buffer->buffer; /* * Check if we are at the end of the buffer. @@ -2342,27 +3665,30 @@ static void rb_advance_iter(struct ring_buffer_iter *iter) /* check for end of page padding */ if ((iter->head >= rb_page_size(iter->head_page)) && (iter->head_page != cpu_buffer->commit_page)) - rb_advance_iter(iter); + rb_inc_iter(iter); +} + +static int rb_lost_events(struct ring_buffer_per_cpu *cpu_buffer) +{ + return cpu_buffer->lost_events; } static struct ring_buffer_event * -rb_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts) +rb_buffer_peek(struct ring_buffer_per_cpu *cpu_buffer, u64 *ts, + unsigned long *lost_events) { - struct ring_buffer_per_cpu *cpu_buffer; struct ring_buffer_event *event; struct buffer_page *reader; int nr_loops = 0; - cpu_buffer = buffer->buffers[cpu]; - again: /* - * We repeat when a timestamp is encountered. It is possible - * to get multiple timestamps from an interrupt entering just - * as one timestamp is about to be written, or from discarded - * commits. The most that we can have is the number on a single page. + * We repeat when a time extend is encountered. + * Since the time extend is always attached to a data event, + * we should never loop more than once. + * (We never hit the following condition more than twice). */ - if (RB_WARN_ON(cpu_buffer, ++nr_loops > RB_TIMESTAMPS_PER_PAGE)) + if (RB_WARN_ON(cpu_buffer, ++nr_loops > 2)) return NULL; reader = rb_get_reader_page(cpu_buffer); @@ -2383,7 +3709,6 @@ rb_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts) * the box. Return the padding, and we will release * the current locks, and try again. */ - rb_advance_reader(cpu_buffer); return event; case RINGBUF_TYPE_TIME_EXTEND: @@ -2399,9 +3724,11 @@ rb_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts) case RINGBUF_TYPE_DATA: if (ts) { *ts = cpu_buffer->read_stamp + event->time_delta; - ring_buffer_normalize_time_stamp(buffer, + ring_buffer_normalize_time_stamp(cpu_buffer->buffer, cpu_buffer->cpu, ts); } + if (lost_events) + *lost_events = rb_lost_events(cpu_buffer); return event; default: @@ -2420,27 +3747,39 @@ rb_iter_peek(struct ring_buffer_iter *iter, u64 *ts) struct ring_buffer_event *event; int nr_loops = 0; - if (ring_buffer_iter_empty(iter)) - return NULL; - cpu_buffer = iter->cpu_buffer; buffer = cpu_buffer->buffer; + /* + * Check if someone performed a consuming read to + * the buffer. A consuming read invalidates the iterator + * and we need to reset the iterator in this case. + */ + if (unlikely(iter->cache_read != cpu_buffer->read || + iter->cache_reader_page != cpu_buffer->reader_page)) + rb_iter_reset(iter); + again: + if (ring_buffer_iter_empty(iter)) + return NULL; + /* - * We repeat when a timestamp is encountered. - * We can get multiple timestamps by nested interrupts or also - * if filtering is on (discarding commits). Since discarding - * commits can be frequent we can get a lot of timestamps. - * But we limit them by not adding timestamps if they begin - * at the start of a page. + * We repeat when a time extend is encountered. + * Since the time extend is always attached to a data event, + * we should never loop more than once. + * (We never hit the following condition more than twice). */ - if (RB_WARN_ON(cpu_buffer, ++nr_loops > RB_TIMESTAMPS_PER_PAGE)) + if (RB_WARN_ON(cpu_buffer, ++nr_loops > 2)) return NULL; if (rb_per_cpu_empty(cpu_buffer)) return NULL; + if (iter->head >= local_read(&iter->head_page->page->commit)) { + rb_inc_iter(iter); + goto again; + } + event = rb_iter_head_event(iter); switch (event->type_len) { @@ -2486,7 +3825,7 @@ static inline int rb_ok_to_lock(void) * buffer too. A one time deal is all you get from reading * the ring buffer from an NMI. */ - if (likely(!in_nmi() && !oops_in_progress)) + if (likely(!in_nmi())) return 1; tracing_off_permanent(); @@ -2498,12 +3837,14 @@ static inline int rb_ok_to_lock(void) * @buffer: The ring buffer to read * @cpu: The cpu to peak at * @ts: The timestamp counter of this event. + * @lost_events: a variable to store if events were lost (may be NULL) * * This will return the event that will be read next, but does * not consume the data. */ struct ring_buffer_event * -ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts) +ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts, + unsigned long *lost_events) { struct ring_buffer_per_cpu *cpu_buffer = buffer->buffers[cpu]; struct ring_buffer_event *event; @@ -2517,16 +3858,16 @@ ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts) again: local_irq_save(flags); if (dolock) - spin_lock(&cpu_buffer->reader_lock); - event = rb_buffer_peek(buffer, cpu, ts); + raw_spin_lock(&cpu_buffer->reader_lock); + event = rb_buffer_peek(cpu_buffer, ts, lost_events); + if (event && event->type_len == RINGBUF_TYPE_PADDING) + rb_advance_reader(cpu_buffer); if (dolock) - spin_unlock(&cpu_buffer->reader_lock); + raw_spin_unlock(&cpu_buffer->reader_lock); local_irq_restore(flags); - if (event && event->type_len == RINGBUF_TYPE_PADDING) { - cpu_relax(); + if (event && event->type_len == RINGBUF_TYPE_PADDING) goto again; - } return event; } @@ -2547,14 +3888,12 @@ ring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts) unsigned long flags; again: - spin_lock_irqsave(&cpu_buffer->reader_lock, flags); + raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags); event = rb_iter_peek(iter, ts); - spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); + raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); - if (event && event->type_len == RINGBUF_TYPE_PADDING) { - cpu_relax(); + if (event && event->type_len == RINGBUF_TYPE_PADDING) goto again; - } return event; } @@ -2562,13 +3901,17 @@ ring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts) /** * ring_buffer_consume - return an event and consume it * @buffer: The ring buffer to get the next event from + * @cpu: the cpu to read the buffer from + * @ts: a variable to store the timestamp (may be NULL) + * @lost_events: a variable to store if events were lost (may be NULL) * * Returns the next event in the ring buffer, and that event is consumed. * Meaning, that sequential reads will keep returning a different event, * and eventually empty the ring buffer if the producer is slower. */ struct ring_buffer_event * -ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts) +ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts, + unsigned long *lost_events) { struct ring_buffer_per_cpu *cpu_buffer; struct ring_buffer_event *event = NULL; @@ -2587,49 +3930,53 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts) cpu_buffer = buffer->buffers[cpu]; local_irq_save(flags); if (dolock) - spin_lock(&cpu_buffer->reader_lock); + raw_spin_lock(&cpu_buffer->reader_lock); - event = rb_buffer_peek(buffer, cpu, ts); - if (!event) - goto out_unlock; - - rb_advance_reader(cpu_buffer); + event = rb_buffer_peek(cpu_buffer, ts, lost_events); + if (event) { + cpu_buffer->lost_events = 0; + rb_advance_reader(cpu_buffer); + } - out_unlock: if (dolock) - spin_unlock(&cpu_buffer->reader_lock); + raw_spin_unlock(&cpu_buffer->reader_lock); local_irq_restore(flags); out: preempt_enable(); - if (event && event->type_len == RINGBUF_TYPE_PADDING) { - cpu_relax(); + if (event && event->type_len == RINGBUF_TYPE_PADDING) goto again; - } return event; } EXPORT_SYMBOL_GPL(ring_buffer_consume); /** - * ring_buffer_read_start - start a non consuming read of the buffer + * ring_buffer_read_prepare - Prepare for a non consuming read of the buffer * @buffer: The ring buffer to read from * @cpu: The cpu buffer to iterate over * - * This starts up an iteration through the buffer. It also disables - * the recording to the buffer until the reading is finished. - * This prevents the reading from being corrupted. This is not - * a consuming read, so a producer is not expected. + * This performs the initial preparations necessary to iterate + * through the buffer. Memory is allocated, buffer recording + * is disabled, and the iterator pointer is returned to the caller. + * + * Disabling buffer recordng prevents the reading from being + * corrupted. This is not a consuming read, so a producer is not + * expected. * - * Must be paired with ring_buffer_finish. + * After a sequence of ring_buffer_read_prepare calls, the user is + * expected to make at least one call to ring_buffer_read_prepare_sync. + * Afterwards, ring_buffer_read_start is invoked to get things going + * for real. + * + * This overall must be paired with ring_buffer_read_finish. */ struct ring_buffer_iter * -ring_buffer_read_start(struct ring_buffer *buffer, int cpu) +ring_buffer_read_prepare(struct ring_buffer *buffer, int cpu) { struct ring_buffer_per_cpu *cpu_buffer; struct ring_buffer_iter *iter; - unsigned long flags; if (!cpumask_test_cpu(cpu, buffer->cpumask)) return NULL; @@ -2642,21 +3989,59 @@ ring_buffer_read_start(struct ring_buffer *buffer, int cpu) iter->cpu_buffer = cpu_buffer; + atomic_inc(&buffer->resize_disabled); atomic_inc(&cpu_buffer->record_disabled); + + return iter; +} +EXPORT_SYMBOL_GPL(ring_buffer_read_prepare); + +/** + * ring_buffer_read_prepare_sync - Synchronize a set of prepare calls + * + * All previously invoked ring_buffer_read_prepare calls to prepare + * iterators will be synchronized. Afterwards, read_buffer_read_start + * calls on those iterators are allowed. + */ +void +ring_buffer_read_prepare_sync(void) +{ synchronize_sched(); +} +EXPORT_SYMBOL_GPL(ring_buffer_read_prepare_sync); - spin_lock_irqsave(&cpu_buffer->reader_lock, flags); - __raw_spin_lock(&cpu_buffer->lock); - rb_iter_reset(iter); - __raw_spin_unlock(&cpu_buffer->lock); - spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); +/** + * ring_buffer_read_start - start a non consuming read of the buffer + * @iter: The iterator returned by ring_buffer_read_prepare + * + * This finalizes the startup of an iteration through the buffer. + * The iterator comes from a call to ring_buffer_read_prepare and + * an intervening ring_buffer_read_prepare_sync must have been + * performed. + * + * Must be paired with ring_buffer_read_finish. + */ +void +ring_buffer_read_start(struct ring_buffer_iter *iter) +{ + struct ring_buffer_per_cpu *cpu_buffer; + unsigned long flags; - return iter; + if (!iter) + return; + + cpu_buffer = iter->cpu_buffer; + + raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags); + arch_spin_lock(&cpu_buffer->lock); + rb_iter_reset(iter); + arch_spin_unlock(&cpu_buffer->lock); + raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); } EXPORT_SYMBOL_GPL(ring_buffer_read_start); /** - * ring_buffer_finish - finish reading the iterator of the buffer + * ring_buffer_read_finish - finish reading the iterator of the buffer * @iter: The iterator retrieved by ring_buffer_start * * This re-enables the recording to the buffer, and frees the @@ -2666,8 +4051,20 @@ void ring_buffer_read_finish(struct ring_buffer_iter *iter) { struct ring_buffer_per_cpu *cpu_buffer = iter->cpu_buffer; + unsigned long flags; + + /* + * Ring buffer is disabled from recording, here's a good place + * to check the integrity of the ring buffer. + * Must prevent readers from trying to read, as the check + * clears the HEAD page and readers require it. + */ + raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags); + rb_check_pages(cpu_buffer); + raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); atomic_dec(&cpu_buffer->record_disabled); + atomic_dec(&cpu_buffer->buffer->resize_disabled); kfree(iter); } EXPORT_SYMBOL_GPL(ring_buffer_read_finish); @@ -2686,20 +4083,18 @@ ring_buffer_read(struct ring_buffer_iter *iter, u64 *ts) struct ring_buffer_per_cpu *cpu_buffer = iter->cpu_buffer; unsigned long flags; + raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags); again: - spin_lock_irqsave(&cpu_buffer->reader_lock, flags); event = rb_iter_peek(iter, ts); if (!event) goto out; + if (event->type_len == RINGBUF_TYPE_PADDING) + goto again; + rb_advance_iter(iter); out: - spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); - - if (event && event->type_len == RINGBUF_TYPE_PADDING) { - cpu_relax(); - goto again; - } + raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); return event; } @@ -2709,17 +4104,28 @@ EXPORT_SYMBOL_GPL(ring_buffer_read); * ring_buffer_size - return the size of the ring buffer (in bytes) * @buffer: The ring buffer. */ -unsigned long ring_buffer_size(struct ring_buffer *buffer) +unsigned long ring_buffer_size(struct ring_buffer *buffer, int cpu) { - return BUF_PAGE_SIZE * buffer->pages; + /* + * Earlier, this method returned + * BUF_PAGE_SIZE * buffer->nr_pages + * Since the nr_pages field is now removed, we have converted this to + * return the per cpu buffer value. + */ + if (!cpumask_test_cpu(cpu, buffer->cpumask)) + return 0; + + return BUF_PAGE_SIZE * buffer->buffers[cpu]->nr_pages; } EXPORT_SYMBOL_GPL(ring_buffer_size); static void rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer) { + rb_head_page_deactivate(cpu_buffer); + cpu_buffer->head_page - = list_entry(cpu_buffer->pages.next, struct buffer_page, list); + = list_entry(cpu_buffer->pages, struct buffer_page, list); local_set(&cpu_buffer->head_page->write, 0); local_set(&cpu_buffer->head_page->entries, 0); local_set(&cpu_buffer->head_page->page->commit, 0); @@ -2730,21 +4136,29 @@ rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer) cpu_buffer->commit_page = cpu_buffer->head_page; INIT_LIST_HEAD(&cpu_buffer->reader_page->list); + INIT_LIST_HEAD(&cpu_buffer->new_pages); local_set(&cpu_buffer->reader_page->write, 0); local_set(&cpu_buffer->reader_page->entries, 0); local_set(&cpu_buffer->reader_page->page->commit, 0); cpu_buffer->reader_page->read = 0; - cpu_buffer->nmi_dropped = 0; - cpu_buffer->commit_overrun = 0; - cpu_buffer->overrun = 0; - cpu_buffer->read = 0; + local_set(&cpu_buffer->entries_bytes, 0); + local_set(&cpu_buffer->overrun, 0); + local_set(&cpu_buffer->commit_overrun, 0); + local_set(&cpu_buffer->dropped_events, 0); local_set(&cpu_buffer->entries, 0); local_set(&cpu_buffer->committing, 0); local_set(&cpu_buffer->commits, 0); + cpu_buffer->read = 0; + cpu_buffer->read_bytes = 0; cpu_buffer->write_stamp = 0; cpu_buffer->read_stamp = 0; + + cpu_buffer->lost_events = 0; + cpu_buffer->last_overrun = 0; + + rb_head_page_activate(cpu_buffer); } /** @@ -2760,19 +4174,28 @@ void ring_buffer_reset_cpu(struct ring_buffer *buffer, int cpu) if (!cpumask_test_cpu(cpu, buffer->cpumask)) return; + atomic_inc(&buffer->resize_disabled); atomic_inc(&cpu_buffer->record_disabled); - spin_lock_irqsave(&cpu_buffer->reader_lock, flags); + /* Make sure all commits have finished */ + synchronize_sched(); - __raw_spin_lock(&cpu_buffer->lock); + raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags); + + if (RB_WARN_ON(cpu_buffer, local_read(&cpu_buffer->committing))) + goto out; + + arch_spin_lock(&cpu_buffer->lock); rb_reset_cpu(cpu_buffer); - __raw_spin_unlock(&cpu_buffer->lock); + arch_spin_unlock(&cpu_buffer->lock); - spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); + out: + raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); atomic_dec(&cpu_buffer->record_disabled); + atomic_dec(&buffer->resize_disabled); } EXPORT_SYMBOL_GPL(ring_buffer_reset_cpu); @@ -2808,10 +4231,10 @@ int ring_buffer_empty(struct ring_buffer *buffer) cpu_buffer = buffer->buffers[cpu]; local_irq_save(flags); if (dolock) - spin_lock(&cpu_buffer->reader_lock); + raw_spin_lock(&cpu_buffer->reader_lock); ret = rb_per_cpu_empty(cpu_buffer); if (dolock) - spin_unlock(&cpu_buffer->reader_lock); + raw_spin_unlock(&cpu_buffer->reader_lock); local_irq_restore(flags); if (!ret) @@ -2842,16 +4265,17 @@ int ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu) cpu_buffer = buffer->buffers[cpu]; local_irq_save(flags); if (dolock) - spin_lock(&cpu_buffer->reader_lock); + raw_spin_lock(&cpu_buffer->reader_lock); ret = rb_per_cpu_empty(cpu_buffer); if (dolock) - spin_unlock(&cpu_buffer->reader_lock); + raw_spin_unlock(&cpu_buffer->reader_lock); local_irq_restore(flags); return ret; } EXPORT_SYMBOL_GPL(ring_buffer_empty_cpu); +#ifdef CONFIG_RING_BUFFER_ALLOW_SWAP /** * ring_buffer_swap_cpu - swap a CPU buffer between two ring buffers * @buffer_a: One buffer to swap with @@ -2873,8 +4297,11 @@ int ring_buffer_swap_cpu(struct ring_buffer *buffer_a, !cpumask_test_cpu(cpu, buffer_b->cpumask)) goto out; + cpu_buffer_a = buffer_a->buffers[cpu]; + cpu_buffer_b = buffer_b->buffers[cpu]; + /* At least make sure the two buffers are somewhat the same */ - if (buffer_a->pages != buffer_b->pages) + if (cpu_buffer_a->nr_pages != cpu_buffer_b->nr_pages) goto out; ret = -EAGAIN; @@ -2888,9 +4315,6 @@ int ring_buffer_swap_cpu(struct ring_buffer *buffer_a, if (atomic_read(&buffer_b->record_disabled)) goto out; - cpu_buffer_a = buffer_a->buffers[cpu]; - cpu_buffer_b = buffer_b->buffers[cpu]; - if (atomic_read(&cpu_buffer_a->record_disabled)) goto out; @@ -2906,24 +4330,33 @@ int ring_buffer_swap_cpu(struct ring_buffer *buffer_a, atomic_inc(&cpu_buffer_a->record_disabled); atomic_inc(&cpu_buffer_b->record_disabled); + ret = -EBUSY; + if (local_read(&cpu_buffer_a->committing)) + goto out_dec; + if (local_read(&cpu_buffer_b->committing)) + goto out_dec; + buffer_a->buffers[cpu] = cpu_buffer_b; buffer_b->buffers[cpu] = cpu_buffer_a; cpu_buffer_b->buffer = buffer_a; cpu_buffer_a->buffer = buffer_b; + ret = 0; + +out_dec: atomic_dec(&cpu_buffer_a->record_disabled); atomic_dec(&cpu_buffer_b->record_disabled); - - ret = 0; out: return ret; } EXPORT_SYMBOL_GPL(ring_buffer_swap_cpu); +#endif /* CONFIG_RING_BUFFER_ALLOW_SWAP */ /** * ring_buffer_alloc_read_page - allocate a page to read from buffer * @buffer: the buffer to allocate for. + * @cpu: the cpu buffer to allocate. * * This function is used in conjunction with ring_buffer_read_page. * When reading a full page from the ring buffer, these functions @@ -2936,16 +4369,17 @@ EXPORT_SYMBOL_GPL(ring_buffer_swap_cpu); * Returns: * The page allocated, or NULL on error. */ -void *ring_buffer_alloc_read_page(struct ring_buffer *buffer) +void *ring_buffer_alloc_read_page(struct ring_buffer *buffer, int cpu) { struct buffer_data_page *bpage; - unsigned long addr; + struct page *page; - addr = __get_free_page(GFP_KERNEL); - if (!addr) + page = alloc_pages_node(cpu_to_node(cpu), + GFP_KERNEL | __GFP_NORETRY, 0); + if (!page) return NULL; - bpage = (void *)addr; + bpage = page_address(page); rb_init_page(bpage); @@ -2980,7 +4414,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_free_read_page); * to swap with a page in the ring buffer. * * for example: - * rpage = ring_buffer_alloc_read_page(buffer); + * rpage = ring_buffer_alloc_read_page(buffer, cpu); * if (!rpage) * return error; * ret = ring_buffer_read_page(buffer, &rpage, len, cpu, 0); @@ -3006,6 +4440,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer, struct ring_buffer_event *event; struct buffer_data_page *bpage; struct buffer_page *reader; + unsigned long missed_events; unsigned long flags; unsigned int commit; unsigned int read; @@ -3031,7 +4466,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer, if (!bpage) goto out; - spin_lock_irqsave(&cpu_buffer->reader_lock, flags); + raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags); reader = rb_get_reader_page(cpu_buffer); if (!reader) @@ -3042,6 +4477,9 @@ int ring_buffer_read_page(struct ring_buffer *buffer, read = reader->read; commit = rb_page_commit(reader); + /* Check if any events were dropped */ + missed_events = cpu_buffer->lost_events; + /* * If this page has been partially read or * if len is not big enough to read the rest of the page or @@ -3062,7 +4500,8 @@ int ring_buffer_read_page(struct ring_buffer *buffer, if (len > (commit - read)) len = (commit - read); - size = rb_event_length(event); + /* Always keep the time extend and data together */ + size = rb_event_ts_length(event); if (len < size) goto out_unlock; @@ -3072,6 +4511,13 @@ int ring_buffer_read_page(struct ring_buffer *buffer, /* Need to copy one event at a time */ do { + /* We need the size of one event, because + * rb_advance_reader only advances by one event, + * whereas rb_event_ts_length may include the size of + * one or two events. + * We have already ensured there's enough space if this + * is a time extend. */ + size = rb_event_length(event); memcpy(bpage->data + pos, rpage->data + rpos, size); len -= size; @@ -3080,9 +4526,13 @@ int ring_buffer_read_page(struct ring_buffer *buffer, rpos = reader->read; pos += size; + if (rpos >= commit) + break; + event = rb_reader_event(cpu_buffer); - size = rb_event_length(event); - } while (len > size); + /* Always keep the time extend and data together */ + size = rb_event_ts_length(event); + } while (len >= size); /* update bpage */ local_set(&bpage->commit, pos); @@ -3092,7 +4542,8 @@ int ring_buffer_read_page(struct ring_buffer *buffer, read = 0; } else { /* update the entry counter */ - cpu_buffer->read += local_read(&reader->entries); + cpu_buffer->read += rb_page_entries(reader); + cpu_buffer->read_bytes += BUF_PAGE_SIZE; /* swap the pages */ rb_init_page(bpage); @@ -3102,87 +4553,50 @@ int ring_buffer_read_page(struct ring_buffer *buffer, local_set(&reader->entries, 0); reader->read = 0; *data_page = bpage; + + /* + * Use the real_end for the data size, + * This gives us a chance to store the lost events + * on the page. + */ + if (reader->real_end) + local_set(&bpage->commit, reader->real_end); } ret = read; + cpu_buffer->lost_events = 0; + + commit = local_read(&bpage->commit); + /* + * Set a flag in the commit field if we lost events + */ + if (missed_events) { + /* If there is room at the end of the page to save the + * missed events, then record it there. + */ + if (BUF_PAGE_SIZE - commit >= sizeof(missed_events)) { + memcpy(&bpage->data[commit], &missed_events, + sizeof(missed_events)); + local_add(RB_MISSED_STORED, &bpage->commit); + commit += sizeof(missed_events); + } + local_add(RB_MISSED_EVENTS, &bpage->commit); + } + + /* + * This page may be off to user land. Zero it out here. + */ + if (commit < BUF_PAGE_SIZE) + memset(&bpage->data[commit], 0, BUF_PAGE_SIZE - commit); + out_unlock: - spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); + raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); out: return ret; } EXPORT_SYMBOL_GPL(ring_buffer_read_page); -#ifdef CONFIG_TRACING -static ssize_t -rb_simple_read(struct file *filp, char __user *ubuf, - size_t cnt, loff_t *ppos) -{ - unsigned long *p = filp->private_data; - char buf[64]; - int r; - - if (test_bit(RB_BUFFERS_DISABLED_BIT, p)) - r = sprintf(buf, "permanently disabled\n"); - else - r = sprintf(buf, "%d\n", test_bit(RB_BUFFERS_ON_BIT, p)); - - return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); -} - -static ssize_t -rb_simple_write(struct file *filp, const char __user *ubuf, - size_t cnt, loff_t *ppos) -{ - unsigned long *p = filp->private_data; - char buf[64]; - unsigned long val; - int ret; - - if (cnt >= sizeof(buf)) - return -EINVAL; - - if (copy_from_user(&buf, ubuf, cnt)) - return -EFAULT; - - buf[cnt] = 0; - - ret = strict_strtoul(buf, 10, &val); - if (ret < 0) - return ret; - - if (val) - set_bit(RB_BUFFERS_ON_BIT, p); - else - clear_bit(RB_BUFFERS_ON_BIT, p); - - (*ppos)++; - - return cnt; -} - -static const struct file_operations rb_simple_fops = { - .open = tracing_open_generic, - .read = rb_simple_read, - .write = rb_simple_write, -}; - - -static __init int rb_init_debugfs(void) -{ - struct dentry *d_tracer; - - d_tracer = tracing_init_dentry(); - - trace_create_file("tracing_on", 0644, d_tracer, - &ring_buffer_flags, &rb_simple_fops); - - return 0; -} - -fs_initcall(rb_init_debugfs); -#endif - #ifdef CONFIG_HOTPLUG_CPU static int rb_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) @@ -3190,6 +4604,8 @@ static int rb_cpu_notify(struct notifier_block *self, struct ring_buffer *buffer = container_of(self, struct ring_buffer, cpu_notify); long cpu = (long)hcpu; + int cpu_i, nr_pages_same; + unsigned int nr_pages; switch (action) { case CPU_UP_PREPARE: @@ -3197,8 +4613,23 @@ static int rb_cpu_notify(struct notifier_block *self, if (cpumask_test_cpu(cpu, buffer->cpumask)) return NOTIFY_OK; + nr_pages = 0; + nr_pages_same = 1; + /* check if all cpu sizes are same */ + for_each_buffer_cpu(buffer, cpu_i) { + /* fill in the size from first enabled cpu */ + if (nr_pages == 0) + nr_pages = buffer->buffers[cpu_i]->nr_pages; + if (nr_pages != buffer->buffers[cpu_i]->nr_pages) { + nr_pages_same = 0; + break; + } + } + /* allocate minimum pages, user can later expand it */ + if (!nr_pages_same) + nr_pages = 2; buffer->buffers[cpu] = - rb_allocate_cpu_buffer(buffer, cpu); + rb_allocate_cpu_buffer(buffer, nr_pages, cpu); if (!buffer->buffers[cpu]) { WARN(1, "failed to allocate ring buffer on CPU %ld\n", cpu); @@ -3221,3 +4652,320 @@ static int rb_cpu_notify(struct notifier_block *self, return NOTIFY_OK; } #endif + +#ifdef CONFIG_RING_BUFFER_STARTUP_TEST +/* + * This is a basic integrity check of the ring buffer. + * Late in the boot cycle this test will run when configured in. + * It will kick off a thread per CPU that will go into a loop + * writing to the per cpu ring buffer various sizes of data. + * Some of the data will be large items, some small. + * + * Another thread is created that goes into a spin, sending out + * IPIs to the other CPUs to also write into the ring buffer. + * this is to test the nesting ability of the buffer. + * + * Basic stats are recorded and reported. If something in the + * ring buffer should happen that's not expected, a big warning + * is displayed and all ring buffers are disabled. + */ +static struct task_struct *rb_threads[NR_CPUS] __initdata; + +struct rb_test_data { + struct ring_buffer *buffer; + unsigned long events; + unsigned long bytes_written; + unsigned long bytes_alloc; + unsigned long bytes_dropped; + unsigned long events_nested; + unsigned long bytes_written_nested; + unsigned long bytes_alloc_nested; + unsigned long bytes_dropped_nested; + int min_size_nested; + int max_size_nested; + int max_size; + int min_size; + int cpu; + int cnt; +}; + +static struct rb_test_data rb_data[NR_CPUS] __initdata; + +/* 1 meg per cpu */ +#define RB_TEST_BUFFER_SIZE 1048576 + +static char rb_string[] __initdata = + "abcdefghijklmnopqrstuvwxyz1234567890!@#$%^&*()?+\\" + "?+|:';\",.<>/?abcdefghijklmnopqrstuvwxyz1234567890" + "!@#$%^&*()?+\\?+|:';\",.<>/?abcdefghijklmnopqrstuv"; + +static bool rb_test_started __initdata; + +struct rb_item { + int size; + char str[]; +}; + +static __init int rb_write_something(struct rb_test_data *data, bool nested) +{ + struct ring_buffer_event *event; + struct rb_item *item; + bool started; + int event_len; + int size; + int len; + int cnt; + + /* Have nested writes different that what is written */ + cnt = data->cnt + (nested ? 27 : 0); + + /* Multiply cnt by ~e, to make some unique increment */ + size = (data->cnt * 68 / 25) % (sizeof(rb_string) - 1); + + len = size + sizeof(struct rb_item); + + started = rb_test_started; + /* read rb_test_started before checking buffer enabled */ + smp_rmb(); + + event = ring_buffer_lock_reserve(data->buffer, len); + if (!event) { + /* Ignore dropped events before test starts. */ + if (started) { + if (nested) + data->bytes_dropped += len; + else + data->bytes_dropped_nested += len; + } + return len; + } + + event_len = ring_buffer_event_length(event); + + if (RB_WARN_ON(data->buffer, event_len < len)) + goto out; + + item = ring_buffer_event_data(event); + item->size = size; + memcpy(item->str, rb_string, size); + + if (nested) { + data->bytes_alloc_nested += event_len; + data->bytes_written_nested += len; + data->events_nested++; + if (!data->min_size_nested || len < data->min_size_nested) + data->min_size_nested = len; + if (len > data->max_size_nested) + data->max_size_nested = len; + } else { + data->bytes_alloc += event_len; + data->bytes_written += len; + data->events++; + if (!data->min_size || len < data->min_size) + data->max_size = len; + if (len > data->max_size) + data->max_size = len; + } + + out: + ring_buffer_unlock_commit(data->buffer, event); + + return 0; +} + +static __init int rb_test(void *arg) +{ + struct rb_test_data *data = arg; + + while (!kthread_should_stop()) { + rb_write_something(data, false); + data->cnt++; + + set_current_state(TASK_INTERRUPTIBLE); + /* Now sleep between a min of 100-300us and a max of 1ms */ + usleep_range(((data->cnt % 3) + 1) * 100, 1000); + } + + return 0; +} + +static __init void rb_ipi(void *ignore) +{ + struct rb_test_data *data; + int cpu = smp_processor_id(); + + data = &rb_data[cpu]; + rb_write_something(data, true); +} + +static __init int rb_hammer_test(void *arg) +{ + while (!kthread_should_stop()) { + + /* Send an IPI to all cpus to write data! */ + smp_call_function(rb_ipi, NULL, 1); + /* No sleep, but for non preempt, let others run */ + schedule(); + } + + return 0; +} + +static __init int test_ringbuffer(void) +{ + struct task_struct *rb_hammer; + struct ring_buffer *buffer; + int cpu; + int ret = 0; + + pr_info("Running ring buffer tests...\n"); + + buffer = ring_buffer_alloc(RB_TEST_BUFFER_SIZE, RB_FL_OVERWRITE); + if (WARN_ON(!buffer)) + return 0; + + /* Disable buffer so that threads can't write to it yet */ + ring_buffer_record_off(buffer); + + for_each_online_cpu(cpu) { + rb_data[cpu].buffer = buffer; + rb_data[cpu].cpu = cpu; + rb_data[cpu].cnt = cpu; + rb_threads[cpu] = kthread_create(rb_test, &rb_data[cpu], + "rbtester/%d", cpu); + if (WARN_ON(!rb_threads[cpu])) { + pr_cont("FAILED\n"); + ret = -1; + goto out_free; + } + + kthread_bind(rb_threads[cpu], cpu); + wake_up_process(rb_threads[cpu]); + } + + /* Now create the rb hammer! */ + rb_hammer = kthread_run(rb_hammer_test, NULL, "rbhammer"); + if (WARN_ON(!rb_hammer)) { + pr_cont("FAILED\n"); + ret = -1; + goto out_free; + } + + ring_buffer_record_on(buffer); + /* + * Show buffer is enabled before setting rb_test_started. + * Yes there's a small race window where events could be + * dropped and the thread wont catch it. But when a ring + * buffer gets enabled, there will always be some kind of + * delay before other CPUs see it. Thus, we don't care about + * those dropped events. We care about events dropped after + * the threads see that the buffer is active. + */ + smp_wmb(); + rb_test_started = true; + + set_current_state(TASK_INTERRUPTIBLE); + /* Just run for 10 seconds */; + schedule_timeout(10 * HZ); + + kthread_stop(rb_hammer); + + out_free: + for_each_online_cpu(cpu) { + if (!rb_threads[cpu]) + break; + kthread_stop(rb_threads[cpu]); + } + if (ret) { + ring_buffer_free(buffer); + return ret; + } + + /* Report! */ + pr_info("finished\n"); + for_each_online_cpu(cpu) { + struct ring_buffer_event *event; + struct rb_test_data *data = &rb_data[cpu]; + struct rb_item *item; + unsigned long total_events; + unsigned long total_dropped; + unsigned long total_written; + unsigned long total_alloc; + unsigned long total_read = 0; + unsigned long total_size = 0; + unsigned long total_len = 0; + unsigned long total_lost = 0; + unsigned long lost; + int big_event_size; + int small_event_size; + + ret = -1; + + total_events = data->events + data->events_nested; + total_written = data->bytes_written + data->bytes_written_nested; + total_alloc = data->bytes_alloc + data->bytes_alloc_nested; + total_dropped = data->bytes_dropped + data->bytes_dropped_nested; + + big_event_size = data->max_size + data->max_size_nested; + small_event_size = data->min_size + data->min_size_nested; + + pr_info("CPU %d:\n", cpu); + pr_info(" events: %ld\n", total_events); + pr_info(" dropped bytes: %ld\n", total_dropped); + pr_info(" alloced bytes: %ld\n", total_alloc); + pr_info(" written bytes: %ld\n", total_written); + pr_info(" biggest event: %d\n", big_event_size); + pr_info(" smallest event: %d\n", small_event_size); + + if (RB_WARN_ON(buffer, total_dropped)) + break; + + ret = 0; + + while ((event = ring_buffer_consume(buffer, cpu, NULL, &lost))) { + total_lost += lost; + item = ring_buffer_event_data(event); + total_len += ring_buffer_event_length(event); + total_size += item->size + sizeof(struct rb_item); + if (memcmp(&item->str[0], rb_string, item->size) != 0) { + pr_info("FAILED!\n"); + pr_info("buffer had: %.*s\n", item->size, item->str); + pr_info("expected: %.*s\n", item->size, rb_string); + RB_WARN_ON(buffer, 1); + ret = -1; + break; + } + total_read++; + } + if (ret) + break; + + ret = -1; + + pr_info(" read events: %ld\n", total_read); + pr_info(" lost events: %ld\n", total_lost); + pr_info(" total events: %ld\n", total_lost + total_read); + pr_info(" recorded len bytes: %ld\n", total_len); + pr_info(" recorded size bytes: %ld\n", total_size); + if (total_lost) + pr_info(" With dropped events, record len and size may not match\n" + " alloced and written from above\n"); + if (!total_lost) { + if (RB_WARN_ON(buffer, total_len != total_alloc || + total_size != total_written)) + break; + } + if (RB_WARN_ON(buffer, total_lost + total_read != total_events)) + break; + + ret = 0; + } + if (!ret) + pr_info("Ring buffer PASSED!\n"); + + ring_buffer_free(buffer); + return 0; +} + +late_initcall(test_ringbuffer); +#endif /* CONFIG_RING_BUFFER_STARTUP_TEST */ diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c index 573d3cc762c..0434ff1b808 100644 --- a/kernel/trace/ring_buffer_benchmark.c +++ b/kernel/trace/ring_buffer_benchmark.c @@ -8,6 +8,7 @@ #include <linux/kthread.h> #include <linux/module.h> #include <linux/time.h> +#include <asm/local.h> struct rb_page { u64 ts; @@ -35,6 +36,28 @@ static int disable_reader; module_param(disable_reader, uint, 0644); MODULE_PARM_DESC(disable_reader, "only run producer"); +static int write_iteration = 50; +module_param(write_iteration, uint, 0644); +MODULE_PARM_DESC(write_iteration, "# of writes between timestamp readings"); + +static int producer_nice = MAX_NICE; +static int consumer_nice = MAX_NICE; + +static int producer_fifo = -1; +static int consumer_fifo = -1; + +module_param(producer_nice, uint, 0644); +MODULE_PARM_DESC(producer_nice, "nice prio for producer"); + +module_param(consumer_nice, uint, 0644); +MODULE_PARM_DESC(consumer_nice, "nice prio for consumer"); + +module_param(producer_fifo, uint, 0644); +MODULE_PARM_DESC(producer_fifo, "fifo prio for producer"); + +module_param(consumer_fifo, uint, 0644); +MODULE_PARM_DESC(consumer_fifo, "fifo prio for consumer"); + static int read_events; static int kill_test; @@ -58,7 +81,7 @@ static enum event_status read_event(int cpu) int *entry; u64 ts; - event = ring_buffer_consume(buffer, cpu, &ts); + event = ring_buffer_consume(buffer, cpu, &ts, NULL); if (!event) return EVENT_DROPPED; @@ -83,14 +106,15 @@ static enum event_status read_page(int cpu) int inc; int i; - bpage = ring_buffer_alloc_read_page(buffer); + bpage = ring_buffer_alloc_read_page(buffer, cpu); if (!bpage) return EVENT_DROPPED; ret = ring_buffer_read_page(buffer, &bpage, PAGE_SIZE, cpu, 1); if (ret >= 0) { rpage = bpage; - commit = local_read(&rpage->commit); + /* The commit may have missed event flags set, clear them */ + commit = local_read(&rpage->commit) & 0xfffff; for (i = 0; i < commit && !kill_test; i += inc) { if (i >= (PAGE_SIZE - offsetof(struct rb_page, data))) { @@ -208,15 +232,18 @@ static void ring_buffer_producer(void) do { struct ring_buffer_event *event; int *entry; - - event = ring_buffer_lock_reserve(buffer, 10); - if (!event) { - missed++; - } else { - hit++; - entry = ring_buffer_event_data(event); - *entry = smp_processor_id(); - ring_buffer_unlock_commit(buffer, event); + int i; + + for (i = 0; i < write_iteration; i++) { + event = ring_buffer_lock_reserve(buffer, 10); + if (!event) { + missed++; + } else { + hit++; + entry = ring_buffer_event_data(event); + *entry = smp_processor_id(); + ring_buffer_unlock_commit(buffer, event); + } } do_gettimeofday(&end_tv); @@ -263,6 +290,27 @@ static void ring_buffer_producer(void) if (kill_test) trace_printk("ERROR!\n"); + + if (!disable_reader) { + if (consumer_fifo < 0) + trace_printk("Running Consumer at nice: %d\n", + consumer_nice); + else + trace_printk("Running Consumer at SCHED_FIFO %d\n", + consumer_fifo); + } + if (producer_fifo < 0) + trace_printk("Running Producer at nice: %d\n", + producer_nice); + else + trace_printk("Running Producer at SCHED_FIFO %d\n", + producer_fifo); + + /* Let the user know that the test is running at low priority */ + if (producer_fifo < 0 && consumer_fifo < 0 && + producer_nice == MAX_NICE && consumer_nice == MAX_NICE) + trace_printk("WARNING!!! This test is running at lowest priority.\n"); + trace_printk("Time: %lld (usecs)\n", time); trace_printk("Overruns: %lld\n", overruns); if (disable_reader) @@ -392,6 +440,27 @@ static int __init ring_buffer_benchmark_init(void) if (IS_ERR(producer)) goto out_kill; + /* + * Run them as low-prio background tasks by default: + */ + if (!disable_reader) { + if (consumer_fifo >= 0) { + struct sched_param param = { + .sched_priority = consumer_fifo + }; + sched_setscheduler(consumer, SCHED_FIFO, ¶m); + } else + set_user_nice(consumer, consumer_nice); + } + + if (producer_fifo >= 0) { + struct sched_param param = { + .sched_priority = consumer_fifo + }; + sched_setscheduler(producer, SCHED_FIFO, ¶m); + } else + set_user_nice(producer, producer_nice); + return 0; out_kill: diff --git a/kernel/trace/rpm-traces.c b/kernel/trace/rpm-traces.c new file mode 100644 index 00000000000..4b3b5eaf94d --- /dev/null +++ b/kernel/trace/rpm-traces.c @@ -0,0 +1,20 @@ +/* + * Power trace points + * + * Copyright (C) 2009 Ming Lei <ming.lei@canonical.com> + */ + +#include <linux/string.h> +#include <linux/types.h> +#include <linux/workqueue.h> +#include <linux/sched.h> +#include <linux/module.h> +#include <linux/usb.h> + +#define CREATE_TRACE_POINTS +#include <trace/events/rpm.h> + +EXPORT_TRACEPOINT_SYMBOL_GPL(rpm_return_int); +EXPORT_TRACEPOINT_SYMBOL_GPL(rpm_idle); +EXPORT_TRACEPOINT_SYMBOL_GPL(rpm_suspend); +EXPORT_TRACEPOINT_SYMBOL_GPL(rpm_resume); diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 3aa0a0dfdfa..291397e6666 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1,7 +1,7 @@ /* * ring buffer based function tracer * - * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> + * Copyright (C) 2007-2012 Steven Rostedt <srostedt@redhat.com> * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> * * Originally taken from the RT patch by: @@ -9,10 +9,10 @@ * * Based on code from the latency_tracer, that is: * Copyright (C) 2004-2006 Ingo Molnar - * Copyright (C) 2004 William Lee Irwin III + * Copyright (C) 2004 Nadia Yvette Chambers */ #include <linux/ring_buffer.h> -#include <linux/utsrelease.h> +#include <generated/utsrelease.h> #include <linux/stacktrace.h> #include <linux/writeback.h> #include <linux/kallsyms.h> @@ -31,25 +31,23 @@ #include <linux/splice.h> #include <linux/kdebug.h> #include <linux/string.h> +#include <linux/rwsem.h> +#include <linux/slab.h> #include <linux/ctype.h> #include <linux/init.h> #include <linux/poll.h> -#include <linux/gfp.h> +#include <linux/nmi.h> #include <linux/fs.h> +#include <linux/sched/rt.h> #include "trace.h" #include "trace_output.h" -#define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE) - -unsigned long __read_mostly tracing_max_latency; -unsigned long __read_mostly tracing_thresh; - /* * On boot up, the ring buffer is set to the minimum size, so that * we do not waste memory on systems that are not using tracing. */ -static int ring_buffer_expanded; +bool ring_buffer_expanded; /* * We need to change this state when a selftest is running. @@ -63,7 +61,7 @@ static bool __read_mostly tracing_selftest_running; /* * If a tracer is running, we do not want to run SELFTEST. */ -static bool __read_mostly tracing_selftest_disabled; +bool __read_mostly tracing_selftest_disabled; /* For tracers that don't implement custom flags */ static struct tracer_opt dummy_tracer_opt[] = { @@ -75,12 +73,20 @@ static struct tracer_flags dummy_tracer_flags = { .opts = dummy_tracer_opt }; -static int dummy_set_flag(u32 old_flags, u32 bit, int set) +static int +dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) { return 0; } /* + * To prevent the comm cache from being overwritten when no + * tracing is active, only save the comm when a trace event + * occurred. + */ +static DEFINE_PER_CPU(bool, trace_cmdline_save); + +/* * Kill all tracing for good (never come back). * It is initialized to 1 but will turn to zero if the initialization * of the tracer is successful. But that is the only place that sets @@ -88,27 +94,9 @@ static int dummy_set_flag(u32 old_flags, u32 bit, int set) */ static int tracing_disabled = 1; -static DEFINE_PER_CPU(local_t, ftrace_cpu_disabled); - -static inline void ftrace_disable_cpu(void) -{ - preempt_disable(); - local_inc(&__get_cpu_var(ftrace_cpu_disabled)); -} - -static inline void ftrace_enable_cpu(void) -{ - local_dec(&__get_cpu_var(ftrace_cpu_disabled)); - preempt_enable(); -} +DEFINE_PER_CPU(int, ftrace_cpu_disabled); -static cpumask_var_t __read_mostly tracing_buffer_mask; - -/* Define which cpu buffers are currently read in trace_pipe */ -static cpumask_var_t tracing_reader_cpumask; - -#define for_each_tracing_cpu(cpu) \ - for_each_cpu(cpu, tracing_buffer_mask) +cpumask_var_t __read_mostly tracing_buffer_mask; /* * ftrace_dump_on_oops - variable to dump ftrace buffer on oops @@ -121,33 +109,90 @@ static cpumask_var_t tracing_reader_cpumask; * * It is default off, but you can enable it with either specifying * "ftrace_dump_on_oops" in the kernel command line, or setting - * /proc/sys/kernel/ftrace_dump_on_oops to true. + * /proc/sys/kernel/ftrace_dump_on_oops + * Set 1 if you want to dump buffers of all CPUs + * Set 2 if you want to dump the buffer of the CPU that triggered oops */ -int ftrace_dump_on_oops; -static int tracing_set_tracer(const char *buf); +enum ftrace_dump_mode ftrace_dump_on_oops; + +/* When set, tracing will stop when a WARN*() is hit */ +int __disable_trace_on_warning; + +static int tracing_set_tracer(struct trace_array *tr, const char *buf); -#define BOOTUP_TRACER_SIZE 100 -static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata; +#define MAX_TRACER_SIZE 100 +static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; static char *default_bootup_tracer; -static int __init set_ftrace(char *str) +static bool allocate_snapshot; + +static int __init set_cmdline_ftrace(char *str) { - strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); + strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); default_bootup_tracer = bootup_tracer_buf; /* We are using ftrace early, expand it */ - ring_buffer_expanded = 1; + ring_buffer_expanded = true; return 1; } -__setup("ftrace=", set_ftrace); +__setup("ftrace=", set_cmdline_ftrace); static int __init set_ftrace_dump_on_oops(char *str) { - ftrace_dump_on_oops = 1; - return 1; + if (*str++ != '=' || !*str) { + ftrace_dump_on_oops = DUMP_ALL; + return 1; + } + + if (!strcmp("orig_cpu", str)) { + ftrace_dump_on_oops = DUMP_ORIG; + return 1; + } + + return 0; } __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); +static int __init stop_trace_on_warning(char *str) +{ + __disable_trace_on_warning = 1; + return 1; +} +__setup("traceoff_on_warning=", stop_trace_on_warning); + +static int __init boot_alloc_snapshot(char *str) +{ + allocate_snapshot = true; + /* We also need the main ring buffer expanded */ + ring_buffer_expanded = true; + return 1; +} +__setup("alloc_snapshot", boot_alloc_snapshot); + + +static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; +static char *trace_boot_options __initdata; + +static int __init set_trace_boot_options(char *str) +{ + strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); + trace_boot_options = trace_boot_options_buf; + return 0; +} +__setup("trace_options=", set_trace_boot_options); + +static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; +static char *trace_boot_clock __initdata; + +static int __init set_trace_boot_clock(char *str) +{ + strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); + trace_boot_clock = trace_boot_clock_buf; + return 0; +} +__setup("trace_clock=", set_trace_boot_clock); + + unsigned long long ns2usecs(cycle_t nsec) { nsec += 500; @@ -169,57 +214,104 @@ unsigned long long ns2usecs(cycle_t nsec) */ static struct trace_array global_trace; -static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); +LIST_HEAD(ftrace_trace_arrays); + +int trace_array_get(struct trace_array *this_tr) +{ + struct trace_array *tr; + int ret = -ENODEV; + + mutex_lock(&trace_types_lock); + list_for_each_entry(tr, &ftrace_trace_arrays, list) { + if (tr == this_tr) { + tr->ref++; + ret = 0; + break; + } + } + mutex_unlock(&trace_types_lock); + + return ret; +} -int filter_current_check_discard(struct ftrace_event_call *call, void *rec, - struct ring_buffer_event *event) +static void __trace_array_put(struct trace_array *this_tr) { - return filter_check_discard(call, rec, global_trace.buffer, event); + WARN_ON(!this_tr->ref); + this_tr->ref--; } -EXPORT_SYMBOL_GPL(filter_current_check_discard); -cycle_t ftrace_now(int cpu) +void trace_array_put(struct trace_array *this_tr) +{ + mutex_lock(&trace_types_lock); + __trace_array_put(this_tr); + mutex_unlock(&trace_types_lock); +} + +int filter_check_discard(struct ftrace_event_file *file, void *rec, + struct ring_buffer *buffer, + struct ring_buffer_event *event) +{ + if (unlikely(file->flags & FTRACE_EVENT_FL_FILTERED) && + !filter_match_preds(file->filter, rec)) { + ring_buffer_discard_commit(buffer, event); + return 1; + } + + return 0; +} +EXPORT_SYMBOL_GPL(filter_check_discard); + +int call_filter_check_discard(struct ftrace_event_call *call, void *rec, + struct ring_buffer *buffer, + struct ring_buffer_event *event) +{ + if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && + !filter_match_preds(call->filter, rec)) { + ring_buffer_discard_commit(buffer, event); + return 1; + } + + return 0; +} +EXPORT_SYMBOL_GPL(call_filter_check_discard); + +static cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) { u64 ts; /* Early boot up does not have a buffer yet */ - if (!global_trace.buffer) + if (!buf->buffer) return trace_clock_local(); - ts = ring_buffer_time_stamp(global_trace.buffer, cpu); - ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); + ts = ring_buffer_time_stamp(buf->buffer, cpu); + ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); return ts; } -/* - * The max_tr is used to snapshot the global_trace when a maximum - * latency is reached. Some tracers will use this to store a maximum - * trace while it continues examining live traces. - * - * The buffers for the max_tr are set up the same as the global_trace. - * When a snapshot is taken, the link list of the max_tr is swapped - * with the link list of the global_trace and the buffers are reset for - * the global_trace so the tracing can continue. - */ -static struct trace_array max_tr; - -static DEFINE_PER_CPU(struct trace_array_cpu, max_data); - -/* tracer_enabled is used to toggle activation of a tracer */ -static int tracer_enabled = 1; +cycle_t ftrace_now(int cpu) +{ + return buffer_ftrace_now(&global_trace.trace_buffer, cpu); +} /** - * tracing_is_enabled - return tracer_enabled status + * tracing_is_enabled - Show if global_trace has been disabled * - * This function is used by other tracers to know the status - * of the tracer_enabled flag. Tracers may use this function - * to know if it should enable their features when starting - * up. See irqsoff tracer for an example (start_irqsoff_tracer). + * Shows if the global trace has been enabled or not. It uses the + * mirror flag "buffer_disabled" to be used in fast paths such as for + * the irqsoff tracer. But it may be inaccurate due to races. If you + * need to know the accurate state, use tracing_is_on() which is a little + * slower, but accurate. */ int tracing_is_enabled(void) { - return tracer_enabled; + /* + * For quick access (irqsoff uses this in fast path), just + * return the mirror variable of the state of the ring buffer. + * It's a little racy, but we don't really care. + */ + smp_rmb(); + return !global_trace.buffer_disabled; } /* @@ -239,47 +331,423 @@ static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; /* trace_types holds a link list of available tracers. */ static struct tracer *trace_types __read_mostly; -/* current_trace points to the tracer that is currently active */ -static struct tracer *current_trace __read_mostly; - /* - * max_tracer_type_len is used to simplify the allocating of - * buffers to read userspace tracer names. We keep track of - * the longest tracer name registered. + * trace_types_lock is used to protect the trace_types list. */ -static int max_tracer_type_len; +DEFINE_MUTEX(trace_types_lock); /* - * trace_types_lock is used to protect the trace_types list. - * This lock is also used to keep user access serialized. - * Accesses from userspace will grab this lock while userspace - * activities happen inside the kernel. + * serialize the access of the ring buffer + * + * ring buffer serializes readers, but it is low level protection. + * The validity of the events (which returns by ring_buffer_peek() ..etc) + * are not protected by ring buffer. + * + * The content of events may become garbage if we allow other process consumes + * these events concurrently: + * A) the page of the consumed events may become a normal page + * (not reader page) in ring buffer, and this page will be rewrited + * by events producer. + * B) The page of the consumed events may become a page for splice_read, + * and this page will be returned to system. + * + * These primitives allow multi process access to different cpu ring buffer + * concurrently. + * + * These primitives don't distinguish read-only and read-consume access. + * Multi read-only access are also serialized. */ -static DEFINE_MUTEX(trace_types_lock); -/* trace_wait is a waitqueue for tasks blocked on trace_poll */ -static DECLARE_WAIT_QUEUE_HEAD(trace_wait); +#ifdef CONFIG_SMP +static DECLARE_RWSEM(all_cpu_access_lock); +static DEFINE_PER_CPU(struct mutex, cpu_access_lock); + +static inline void trace_access_lock(int cpu) +{ + if (cpu == RING_BUFFER_ALL_CPUS) { + /* gain it for accessing the whole ring buffer. */ + down_write(&all_cpu_access_lock); + } else { + /* gain it for accessing a cpu ring buffer. */ + + /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ + down_read(&all_cpu_access_lock); + + /* Secondly block other access to this @cpu ring buffer. */ + mutex_lock(&per_cpu(cpu_access_lock, cpu)); + } +} + +static inline void trace_access_unlock(int cpu) +{ + if (cpu == RING_BUFFER_ALL_CPUS) { + up_write(&all_cpu_access_lock); + } else { + mutex_unlock(&per_cpu(cpu_access_lock, cpu)); + up_read(&all_cpu_access_lock); + } +} + +static inline void trace_access_lock_init(void) +{ + int cpu; + + for_each_possible_cpu(cpu) + mutex_init(&per_cpu(cpu_access_lock, cpu)); +} + +#else + +static DEFINE_MUTEX(access_lock); + +static inline void trace_access_lock(int cpu) +{ + (void)cpu; + mutex_lock(&access_lock); +} + +static inline void trace_access_unlock(int cpu) +{ + (void)cpu; + mutex_unlock(&access_lock); +} + +static inline void trace_access_lock_init(void) +{ +} + +#endif /* trace_flags holds trace_options default values */ unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | - TRACE_ITER_GRAPH_TIME; + TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | + TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION; + +static void tracer_tracing_on(struct trace_array *tr) +{ + if (tr->trace_buffer.buffer) + ring_buffer_record_on(tr->trace_buffer.buffer); + /* + * This flag is looked at when buffers haven't been allocated + * yet, or by some tracers (like irqsoff), that just want to + * know if the ring buffer has been disabled, but it can handle + * races of where it gets disabled but we still do a record. + * As the check is in the fast path of the tracers, it is more + * important to be fast than accurate. + */ + tr->buffer_disabled = 0; + /* Make the flag seen by readers */ + smp_wmb(); +} /** - * trace_wake_up - wake up tasks waiting for trace input + * tracing_on - enable tracing buffers * - * Simply wakes up any task that is blocked on the trace_wait - * queue. These is used with trace_poll for tasks polling the trace. + * This function enables tracing buffers that may have been + * disabled with tracing_off. + */ +void tracing_on(void) +{ + tracer_tracing_on(&global_trace); +} +EXPORT_SYMBOL_GPL(tracing_on); + +/** + * __trace_puts - write a constant string into the trace buffer. + * @ip: The address of the caller + * @str: The constant string to write + * @size: The size of the string. */ -void trace_wake_up(void) +int __trace_puts(unsigned long ip, const char *str, int size) { + struct ring_buffer_event *event; + struct ring_buffer *buffer; + struct print_entry *entry; + unsigned long irq_flags; + int alloc; + int pc; + + if (!(trace_flags & TRACE_ITER_PRINTK)) + return 0; + + pc = preempt_count(); + + if (unlikely(tracing_selftest_running || tracing_disabled)) + return 0; + + alloc = sizeof(*entry) + size + 2; /* possible \n added */ + + local_save_flags(irq_flags); + buffer = global_trace.trace_buffer.buffer; + event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, + irq_flags, pc); + if (!event) + return 0; + + entry = ring_buffer_event_data(event); + entry->ip = ip; + + memcpy(&entry->buf, str, size); + + /* Add a newline if necessary */ + if (entry->buf[size - 1] != '\n') { + entry->buf[size] = '\n'; + entry->buf[size + 1] = '\0'; + } else + entry->buf[size] = '\0'; + + __buffer_unlock_commit(buffer, event); + ftrace_trace_stack(buffer, irq_flags, 4, pc); + + return size; +} +EXPORT_SYMBOL_GPL(__trace_puts); + +/** + * __trace_bputs - write the pointer to a constant string into trace buffer + * @ip: The address of the caller + * @str: The constant string to write to the buffer to + */ +int __trace_bputs(unsigned long ip, const char *str) +{ + struct ring_buffer_event *event; + struct ring_buffer *buffer; + struct bputs_entry *entry; + unsigned long irq_flags; + int size = sizeof(struct bputs_entry); + int pc; + + if (!(trace_flags & TRACE_ITER_PRINTK)) + return 0; + + pc = preempt_count(); + + if (unlikely(tracing_selftest_running || tracing_disabled)) + return 0; + + local_save_flags(irq_flags); + buffer = global_trace.trace_buffer.buffer; + event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, + irq_flags, pc); + if (!event) + return 0; + + entry = ring_buffer_event_data(event); + entry->ip = ip; + entry->str = str; + + __buffer_unlock_commit(buffer, event); + ftrace_trace_stack(buffer, irq_flags, 4, pc); + + return 1; +} +EXPORT_SYMBOL_GPL(__trace_bputs); + +#ifdef CONFIG_TRACER_SNAPSHOT +/** + * trace_snapshot - take a snapshot of the current buffer. + * + * This causes a swap between the snapshot buffer and the current live + * tracing buffer. You can use this to take snapshots of the live + * trace when some condition is triggered, but continue to trace. + * + * Note, make sure to allocate the snapshot with either + * a tracing_snapshot_alloc(), or by doing it manually + * with: echo 1 > /sys/kernel/debug/tracing/snapshot + * + * If the snapshot buffer is not allocated, it will stop tracing. + * Basically making a permanent snapshot. + */ +void tracing_snapshot(void) +{ + struct trace_array *tr = &global_trace; + struct tracer *tracer = tr->current_trace; + unsigned long flags; + + if (in_nmi()) { + internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); + internal_trace_puts("*** snapshot is being ignored ***\n"); + return; + } + + if (!tr->allocated_snapshot) { + internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); + internal_trace_puts("*** stopping trace here! ***\n"); + tracing_off(); + return; + } + + /* Note, snapshot can not be used when the tracer uses it */ + if (tracer->use_max_tr) { + internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); + internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); + return; + } + + local_irq_save(flags); + update_max_tr(tr, current, smp_processor_id()); + local_irq_restore(flags); +} +EXPORT_SYMBOL_GPL(tracing_snapshot); + +static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, + struct trace_buffer *size_buf, int cpu_id); +static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); + +static int alloc_snapshot(struct trace_array *tr) +{ + int ret; + + if (!tr->allocated_snapshot) { + + /* allocate spare buffer */ + ret = resize_buffer_duplicate_size(&tr->max_buffer, + &tr->trace_buffer, RING_BUFFER_ALL_CPUS); + if (ret < 0) + return ret; + + tr->allocated_snapshot = true; + } + + return 0; +} + +static void free_snapshot(struct trace_array *tr) +{ + /* + * We don't free the ring buffer. instead, resize it because + * The max_tr ring buffer has some state (e.g. ring->clock) and + * we want preserve it. + */ + ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); + set_buffer_entries(&tr->max_buffer, 1); + tracing_reset_online_cpus(&tr->max_buffer); + tr->allocated_snapshot = false; +} + +/** + * tracing_alloc_snapshot - allocate snapshot buffer. + * + * This only allocates the snapshot buffer if it isn't already + * allocated - it doesn't also take a snapshot. + * + * This is meant to be used in cases where the snapshot buffer needs + * to be set up for events that can't sleep but need to be able to + * trigger a snapshot. + */ +int tracing_alloc_snapshot(void) +{ + struct trace_array *tr = &global_trace; + int ret; + + ret = alloc_snapshot(tr); + WARN_ON(ret < 0); + + return ret; +} +EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); + +/** + * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. + * + * This is similar to trace_snapshot(), but it will allocate the + * snapshot buffer if it isn't already allocated. Use this only + * where it is safe to sleep, as the allocation may sleep. + * + * This causes a swap between the snapshot buffer and the current live + * tracing buffer. You can use this to take snapshots of the live + * trace when some condition is triggered, but continue to trace. + */ +void tracing_snapshot_alloc(void) +{ + int ret; + + ret = tracing_alloc_snapshot(); + if (ret < 0) + return; + + tracing_snapshot(); +} +EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); +#else +void tracing_snapshot(void) +{ + WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); +} +EXPORT_SYMBOL_GPL(tracing_snapshot); +int tracing_alloc_snapshot(void) +{ + WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); + return -ENODEV; +} +EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); +void tracing_snapshot_alloc(void) +{ + /* Give warning */ + tracing_snapshot(); +} +EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); +#endif /* CONFIG_TRACER_SNAPSHOT */ + +static void tracer_tracing_off(struct trace_array *tr) +{ + if (tr->trace_buffer.buffer) + ring_buffer_record_off(tr->trace_buffer.buffer); /* - * The runqueue_is_locked() can fail, but this is the best we - * have for now: + * This flag is looked at when buffers haven't been allocated + * yet, or by some tracers (like irqsoff), that just want to + * know if the ring buffer has been disabled, but it can handle + * races of where it gets disabled but we still do a record. + * As the check is in the fast path of the tracers, it is more + * important to be fast than accurate. */ - if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) - wake_up(&trace_wait); + tr->buffer_disabled = 1; + /* Make the flag seen by readers */ + smp_wmb(); +} + +/** + * tracing_off - turn off tracing buffers + * + * This function stops the tracing buffers from recording data. + * It does not disable any overhead the tracers themselves may + * be causing. This function simply causes all recording to + * the ring buffers to fail. + */ +void tracing_off(void) +{ + tracer_tracing_off(&global_trace); +} +EXPORT_SYMBOL_GPL(tracing_off); + +void disable_trace_on_warning(void) +{ + if (__disable_trace_on_warning) + tracing_off(); +} + +/** + * tracer_tracing_is_on - show real state of ring buffer enabled + * @tr : the trace array to know if ring buffer is enabled + * + * Shows real state of the ring buffer if it is enabled or not. + */ +static int tracer_tracing_is_on(struct trace_array *tr) +{ + if (tr->trace_buffer.buffer) + return ring_buffer_record_is_on(tr->trace_buffer.buffer); + return !tr->buffer_disabled; +} + +/** + * tracing_is_on - show state of ring buffers enabled + */ +int tracing_is_on(void) +{ + return tracer_tracing_is_on(&global_trace); } +EXPORT_SYMBOL_GPL(tracing_is_on); static int __init set_buf_size(char *str) { @@ -296,6 +764,21 @@ static int __init set_buf_size(char *str) } __setup("trace_buf_size=", set_buf_size); +static int __init set_tracing_thresh(char *str) +{ + unsigned long threshold; + int ret; + + if (!str) + return 0; + ret = kstrtoul(str, 0, &threshold); + if (ret < 0) + return 0; + tracing_thresh = threshold * 1000; + return 1; +} +__setup("tracing_thresh=", set_tracing_thresh); + unsigned long nsecs_to_usecs(unsigned long nsecs) { return nsecs / 1000; @@ -312,7 +795,6 @@ static const char *trace_options[] = { "bin", "block", "stacktrace", - "sched-tree", "trace_printk", "ftrace_preempt", "branch", @@ -322,49 +804,137 @@ static const char *trace_options[] = { "printk-msg-only", "context-info", "latency-format", - "global-clock", "sleep-time", "graph-time", + "record-cmd", + "overwrite", + "disable_on_free", + "irq-info", + "markers", + "function-trace", NULL }; +static struct { + u64 (*func)(void); + const char *name; + int in_ns; /* is this clock in nanoseconds? */ +} trace_clocks[] = { + { trace_clock_local, "local", 1 }, + { trace_clock_global, "global", 1 }, + { trace_clock_counter, "counter", 0 }, + { trace_clock_jiffies, "uptime", 0 }, + { trace_clock, "perf", 1 }, + ARCH_TRACE_CLOCKS +}; + /* - * ftrace_max_lock is used to protect the swapping of buffers - * when taking a max snapshot. The buffers themselves are - * protected by per_cpu spinlocks. But the action of the swap - * needs its own lock. - * - * This is defined as a raw_spinlock_t in order to help - * with performance when lockdep debugging is enabled. + * trace_parser_get_init - gets the buffer for trace parser */ -static raw_spinlock_t ftrace_max_lock = - (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; +int trace_parser_get_init(struct trace_parser *parser, int size) +{ + memset(parser, 0, sizeof(*parser)); + + parser->buffer = kmalloc(size, GFP_KERNEL); + if (!parser->buffer) + return 1; + + parser->size = size; + return 0; +} /* - * Copy the new maximum trace into the separate maximum-trace - * structure. (this way the maximum trace is permanently saved, - * for later retrieval via /sys/kernel/debug/tracing/latency_trace) + * trace_parser_put - frees the buffer for trace parser */ -static void -__update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) +void trace_parser_put(struct trace_parser *parser) { - struct trace_array_cpu *data = tr->data[cpu]; + kfree(parser->buffer); +} - max_tr.cpu = cpu; - max_tr.time_start = data->preempt_timestamp; +/* + * trace_get_user - reads the user input string separated by space + * (matched by isspace(ch)) + * + * For each string found the 'struct trace_parser' is updated, + * and the function returns. + * + * Returns number of bytes read. + * + * See kernel/trace/trace.h for 'struct trace_parser' details. + */ +int trace_get_user(struct trace_parser *parser, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + char ch; + size_t read = 0; + ssize_t ret; - data = max_tr.data[cpu]; - data->saved_latency = tracing_max_latency; + if (!*ppos) + trace_parser_clear(parser); - memcpy(data->comm, tsk->comm, TASK_COMM_LEN); - data->pid = tsk->pid; - data->uid = task_uid(tsk); - data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; - data->policy = tsk->policy; - data->rt_priority = tsk->rt_priority; + ret = get_user(ch, ubuf++); + if (ret) + goto out; - /* record this tasks comm */ - tracing_record_cmdline(tsk); + read++; + cnt--; + + /* + * The parser is not finished with the last write, + * continue reading the user input without skipping spaces. + */ + if (!parser->cont) { + /* skip white space */ + while (cnt && isspace(ch)) { + ret = get_user(ch, ubuf++); + if (ret) + goto out; + read++; + cnt--; + } + + /* only spaces were written */ + if (isspace(ch)) { + *ppos += read; + ret = read; + goto out; + } + + parser->idx = 0; + } + + /* read the non-space input */ + while (cnt && !isspace(ch)) { + if (parser->idx < parser->size - 1) + parser->buffer[parser->idx++] = ch; + else { + ret = -EINVAL; + goto out; + } + ret = get_user(ch, ubuf++); + if (ret) + goto out; + read++; + cnt--; + } + + /* We either got finished input or we have to wait for another call. */ + if (isspace(ch)) { + parser->buffer[parser->idx] = 0; + parser->cont = false; + } else if (parser->idx < parser->size - 1) { + parser->cont = true; + parser->buffer[parser->idx++] = ch; + } else { + ret = -EINVAL; + goto out; + } + + *ppos += read; + ret = read; + +out: + return ret; } ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) @@ -394,7 +964,6 @@ ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) { int len; - void *ret; if (s->len <= s->readpos) return -EBUSY; @@ -402,14 +971,54 @@ static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) len = s->len - s->readpos; if (cnt > len) cnt = len; - ret = memcpy(buf, s->buffer + s->readpos, cnt); - if (!ret) - return -EFAULT; + memcpy(buf, s->buffer + s->readpos, cnt); s->readpos += cnt; return cnt; } +unsigned long __read_mostly tracing_thresh; + +#ifdef CONFIG_TRACER_MAX_TRACE +/* + * Copy the new maximum trace into the separate maximum-trace + * structure. (this way the maximum trace is permanently saved, + * for later retrieval via /sys/kernel/debug/tracing/latency_trace) + */ +static void +__update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) +{ + struct trace_buffer *trace_buf = &tr->trace_buffer; + struct trace_buffer *max_buf = &tr->max_buffer; + struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); + struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); + + max_buf->cpu = cpu; + max_buf->time_start = data->preempt_timestamp; + + max_data->saved_latency = tr->max_latency; + max_data->critical_start = data->critical_start; + max_data->critical_end = data->critical_end; + + memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); + max_data->pid = tsk->pid; + /* + * If tsk == current, then use current_uid(), as that does not use + * RCU. The irq tracer can be called out of RCU scope. + */ + if (tsk == current) + max_data->uid = current_uid(); + else + max_data->uid = task_uid(tsk); + + max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; + max_data->policy = tsk->policy; + max_data->rt_priority = tsk->rt_priority; + + /* record this tasks comm */ + tracing_record_cmdline(tsk); +} + /** * update_max_tr - snapshot all trace buffers from global_trace to max_tr * @tr: tracer @@ -422,20 +1031,27 @@ static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) { - struct ring_buffer *buf = tr->buffer; + struct ring_buffer *buf; + + if (tr->stop_count) + return; WARN_ON_ONCE(!irqs_disabled()); - __raw_spin_lock(&ftrace_max_lock); - tr->buffer = max_tr.buffer; - max_tr.buffer = buf; + if (!tr->allocated_snapshot) { + /* Only the nop tracer should hit this when disabling */ + WARN_ON_ONCE(tr->current_trace != &nop_trace); + return; + } + + arch_spin_lock(&tr->max_lock); - ftrace_disable_cpu(); - ring_buffer_reset(tr->buffer); - ftrace_enable_cpu(); + buf = tr->trace_buffer.buffer; + tr->trace_buffer.buffer = tr->max_buffer.buffer; + tr->max_buffer.buffer = buf; __update_max_tr(tr, tsk, cpu); - __raw_spin_unlock(&ftrace_max_lock); + arch_spin_unlock(&tr->max_lock); } /** @@ -451,22 +1067,113 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) { int ret; + if (tr->stop_count) + return; + WARN_ON_ONCE(!irqs_disabled()); - __raw_spin_lock(&ftrace_max_lock); + if (!tr->allocated_snapshot) { + /* Only the nop tracer should hit this when disabling */ + WARN_ON_ONCE(tr->current_trace != &nop_trace); + return; + } - ftrace_disable_cpu(); + arch_spin_lock(&tr->max_lock); - ring_buffer_reset(max_tr.buffer); - ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); + ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); - ftrace_enable_cpu(); + if (ret == -EBUSY) { + /* + * We failed to swap the buffer due to a commit taking + * place on this CPU. We fail to record, but we reset + * the max trace buffer (no one writes directly to it) + * and flag that it failed. + */ + trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, + "Failed to swap buffers due to commit in progress\n"); + } - WARN_ON_ONCE(ret && ret != -EAGAIN); + WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); __update_max_tr(tr, tsk, cpu); - __raw_spin_unlock(&ftrace_max_lock); + arch_spin_unlock(&tr->max_lock); +} +#endif /* CONFIG_TRACER_MAX_TRACE */ + +static int wait_on_pipe(struct trace_iterator *iter) +{ + /* Iterators are static, they should be filled or empty */ + if (trace_buffer_iter(iter, iter->cpu_file)) + return 0; + + return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file); } +#ifdef CONFIG_FTRACE_STARTUP_TEST +static int run_tracer_selftest(struct tracer *type) +{ + struct trace_array *tr = &global_trace; + struct tracer *saved_tracer = tr->current_trace; + int ret; + + if (!type->selftest || tracing_selftest_disabled) + return 0; + + /* + * Run a selftest on this tracer. + * Here we reset the trace buffer, and set the current + * tracer to be this tracer. The tracer can then run some + * internal tracing to verify that everything is in order. + * If we fail, we do not register this tracer. + */ + tracing_reset_online_cpus(&tr->trace_buffer); + + tr->current_trace = type; + +#ifdef CONFIG_TRACER_MAX_TRACE + if (type->use_max_tr) { + /* If we expanded the buffers, make sure the max is expanded too */ + if (ring_buffer_expanded) + ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, + RING_BUFFER_ALL_CPUS); + tr->allocated_snapshot = true; + } +#endif + + /* the test is responsible for initializing and enabling */ + pr_info("Testing tracer %s: ", type->name); + ret = type->selftest(type, tr); + /* the test is responsible for resetting too */ + tr->current_trace = saved_tracer; + if (ret) { + printk(KERN_CONT "FAILED!\n"); + /* Add the warning after printing 'FAILED' */ + WARN_ON(1); + return -1; + } + /* Only reset on passing, to avoid touching corrupted buffers */ + tracing_reset_online_cpus(&tr->trace_buffer); + +#ifdef CONFIG_TRACER_MAX_TRACE + if (type->use_max_tr) { + tr->allocated_snapshot = false; + + /* Shrink the max buffer again */ + if (ring_buffer_expanded) + ring_buffer_resize(tr->max_buffer.buffer, 1, + RING_BUFFER_ALL_CPUS); + } +#endif + + printk(KERN_CONT "PASSED\n"); + return 0; +} +#else +static inline int run_tracer_selftest(struct tracer *type) +{ + return 0; +} +#endif /* CONFIG_FTRACE_STARTUP_TEST */ + /** * register_tracer - register a tracer with the ftrace system. * @type - the plugin for the tracer @@ -474,11 +1181,8 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) * Register a new plugin tracer. */ int register_tracer(struct tracer *type) -__releases(kernel_lock) -__acquires(kernel_lock) { struct tracer *t; - int len; int ret = 0; if (!type->name) { @@ -486,13 +1190,11 @@ __acquires(kernel_lock) return -1; } - /* - * When this gets called we hold the BKL which means that - * preemption is disabled. Various trace selftests however - * need to disable and enable preemption for successful tests. - * So we drop the BKL here and grab it after the tests again. - */ - unlock_kernel(); + if (strlen(type->name) >= MAX_TRACER_SIZE) { + pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); + return -1; + } + mutex_lock(&trace_types_lock); tracing_selftest_running = true; @@ -500,7 +1202,7 @@ __acquires(kernel_lock) for (t = trace_types; t; t = t->next) { if (strcmp(type->name, t->name) == 0) { /* already found */ - pr_info("Trace %s already registered\n", + pr_info("Tracer %s already registered\n", type->name); ret = -1; goto out; @@ -514,49 +1216,13 @@ __acquires(kernel_lock) else if (!type->flags->opts) type->flags->opts = dummy_tracer_opt; - if (!type->wait_pipe) - type->wait_pipe = default_wait_pipe; - -#ifdef CONFIG_FTRACE_STARTUP_TEST - if (type->selftest && !tracing_selftest_disabled) { - struct tracer *saved_tracer = current_trace; - struct trace_array *tr = &global_trace; - int i; - - /* - * Run a selftest on this tracer. - * Here we reset the trace buffer, and set the current - * tracer to be this tracer. The tracer can then run some - * internal tracing to verify that everything is in order. - * If we fail, we do not register this tracer. - */ - for_each_tracing_cpu(i) - tracing_reset(tr, i); - - current_trace = type; - /* the test is responsible for initializing and enabling */ - pr_info("Testing tracer %s: ", type->name); - ret = type->selftest(type, tr); - /* the test is responsible for resetting too */ - current_trace = saved_tracer; - if (ret) { - printk(KERN_CONT "FAILED!\n"); - goto out; - } - /* Only reset on passing, to avoid touching corrupted buffers */ - for_each_tracing_cpu(i) - tracing_reset(tr, i); - - printk(KERN_CONT "PASSED\n"); - } -#endif + ret = run_tracer_selftest(type); + if (ret < 0) + goto out; type->next = trace_types; trace_types = type; - len = strlen(type->name); - if (len > max_tracer_type_len) - max_tracer_type_len = len; out: tracing_selftest_running = false; @@ -565,123 +1231,144 @@ __acquires(kernel_lock) if (ret || !default_bootup_tracer) goto out_unlock; - if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE)) + if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) goto out_unlock; printk(KERN_INFO "Starting tracer '%s'\n", type->name); /* Do we want this tracer to start on bootup? */ - tracing_set_tracer(type->name); + tracing_set_tracer(&global_trace, type->name); default_bootup_tracer = NULL; /* disable other selftests, since this will break it. */ - tracing_selftest_disabled = 1; + tracing_selftest_disabled = true; #ifdef CONFIG_FTRACE_STARTUP_TEST printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", type->name); #endif out_unlock: - lock_kernel(); return ret; } -void unregister_tracer(struct tracer *type) +void tracing_reset(struct trace_buffer *buf, int cpu) { - struct tracer **t; - int len; + struct ring_buffer *buffer = buf->buffer; - mutex_lock(&trace_types_lock); - for (t = &trace_types; *t; t = &(*t)->next) { - if (*t == type) - goto found; - } - pr_info("Trace %s not registered\n", type->name); - goto out; - - found: - *t = (*t)->next; - - if (type == current_trace && tracer_enabled) { - tracer_enabled = 0; - tracing_stop(); - if (current_trace->stop) - current_trace->stop(&global_trace); - current_trace = &nop_trace; - } + if (!buffer) + return; - if (strlen(type->name) != max_tracer_type_len) - goto out; + ring_buffer_record_disable(buffer); - max_tracer_type_len = 0; - for (t = &trace_types; *t; t = &(*t)->next) { - len = strlen((*t)->name); - if (len > max_tracer_type_len) - max_tracer_type_len = len; - } - out: - mutex_unlock(&trace_types_lock); -} + /* Make sure all commits have finished */ + synchronize_sched(); + ring_buffer_reset_cpu(buffer, cpu); -void tracing_reset(struct trace_array *tr, int cpu) -{ - ftrace_disable_cpu(); - ring_buffer_reset_cpu(tr->buffer, cpu); - ftrace_enable_cpu(); + ring_buffer_record_enable(buffer); } -void tracing_reset_online_cpus(struct trace_array *tr) +void tracing_reset_online_cpus(struct trace_buffer *buf) { + struct ring_buffer *buffer = buf->buffer; int cpu; - tr->time_start = ftrace_now(tr->cpu); + if (!buffer) + return; + + ring_buffer_record_disable(buffer); + + /* Make sure all commits have finished */ + synchronize_sched(); + + buf->time_start = buffer_ftrace_now(buf, buf->cpu); for_each_online_cpu(cpu) - tracing_reset(tr, cpu); -} + ring_buffer_reset_cpu(buffer, cpu); -void tracing_reset_current(int cpu) -{ - tracing_reset(&global_trace, cpu); + ring_buffer_record_enable(buffer); } -void tracing_reset_current_online_cpus(void) +/* Must have trace_types_lock held */ +void tracing_reset_all_online_cpus(void) { - tracing_reset_online_cpus(&global_trace); + struct trace_array *tr; + + list_for_each_entry(tr, &ftrace_trace_arrays, list) { + tracing_reset_online_cpus(&tr->trace_buffer); +#ifdef CONFIG_TRACER_MAX_TRACE + tracing_reset_online_cpus(&tr->max_buffer); +#endif + } } -#define SAVED_CMDLINES 128 +#define SAVED_CMDLINES_DEFAULT 128 #define NO_CMDLINE_MAP UINT_MAX -static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; -static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; -static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; -static int cmdline_idx; -static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; +static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; +struct saved_cmdlines_buffer { + unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; + unsigned *map_cmdline_to_pid; + unsigned cmdline_num; + int cmdline_idx; + char *saved_cmdlines; +}; +static struct saved_cmdlines_buffer *savedcmd; /* temporary disable recording */ static atomic_t trace_record_cmdline_disabled __read_mostly; -static void trace_init_cmdlines(void) +static inline char *get_saved_cmdlines(int idx) { - memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); - memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); - cmdline_idx = 0; + return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN]; } -static int trace_stop_count; -static DEFINE_SPINLOCK(tracing_start_lock); +static inline void set_cmdline(int idx, const char *cmdline) +{ + memcpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); +} -/** - * ftrace_off_permanent - disable all ftrace code permanently - * - * This should only be called when a serious anomally has - * been detected. This will turn off the function tracing, - * ring buffers, and other tracing utilites. It takes no - * locks and can be called from any context. - */ -void ftrace_off_permanent(void) +static int allocate_cmdlines_buffer(unsigned int val, + struct saved_cmdlines_buffer *s) +{ + s->map_cmdline_to_pid = kmalloc(val * sizeof(*s->map_cmdline_to_pid), + GFP_KERNEL); + if (!s->map_cmdline_to_pid) + return -ENOMEM; + + s->saved_cmdlines = kmalloc(val * TASK_COMM_LEN, GFP_KERNEL); + if (!s->saved_cmdlines) { + kfree(s->map_cmdline_to_pid); + return -ENOMEM; + } + + s->cmdline_idx = 0; + s->cmdline_num = val; + memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP, + sizeof(s->map_pid_to_cmdline)); + memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP, + val * sizeof(*s->map_cmdline_to_pid)); + + return 0; +} + +static int trace_create_savedcmd(void) +{ + int ret; + + savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL); + if (!savedcmd) + return -ENOMEM; + + ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd); + if (ret < 0) { + kfree(savedcmd); + savedcmd = NULL; + return -ENOMEM; + } + + return 0; +} + +int is_tracing_stopped(void) { - tracing_disabled = 1; - ftrace_stop(); - tracing_off_permanent(); + return global_trace.stop_count; } /** @@ -698,28 +1385,64 @@ void tracing_start(void) if (tracing_disabled) return; - spin_lock_irqsave(&tracing_start_lock, flags); - if (--trace_stop_count) { - if (trace_stop_count < 0) { + raw_spin_lock_irqsave(&global_trace.start_lock, flags); + if (--global_trace.stop_count) { + if (global_trace.stop_count < 0) { /* Someone screwed up their debugging */ WARN_ON_ONCE(1); - trace_stop_count = 0; + global_trace.stop_count = 0; } goto out; } + /* Prevent the buffers from switching */ + arch_spin_lock(&global_trace.max_lock); - buffer = global_trace.buffer; + buffer = global_trace.trace_buffer.buffer; if (buffer) ring_buffer_record_enable(buffer); - buffer = max_tr.buffer; +#ifdef CONFIG_TRACER_MAX_TRACE + buffer = global_trace.max_buffer.buffer; + if (buffer) + ring_buffer_record_enable(buffer); +#endif + + arch_spin_unlock(&global_trace.max_lock); + + out: + raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); +} + +static void tracing_start_tr(struct trace_array *tr) +{ + struct ring_buffer *buffer; + unsigned long flags; + + if (tracing_disabled) + return; + + /* If global, we need to also start the max tracer */ + if (tr->flags & TRACE_ARRAY_FL_GLOBAL) + return tracing_start(); + + raw_spin_lock_irqsave(&tr->start_lock, flags); + + if (--tr->stop_count) { + if (tr->stop_count < 0) { + /* Someone screwed up their debugging */ + WARN_ON_ONCE(1); + tr->stop_count = 0; + } + goto out; + } + + buffer = tr->trace_buffer.buffer; if (buffer) ring_buffer_record_enable(buffer); - ftrace_start(); out: - spin_unlock_irqrestore(&tracing_start_lock, flags); + raw_spin_unlock_irqrestore(&tr->start_lock, flags); } /** @@ -733,31 +1456,58 @@ void tracing_stop(void) struct ring_buffer *buffer; unsigned long flags; - ftrace_stop(); - spin_lock_irqsave(&tracing_start_lock, flags); - if (trace_stop_count++) + raw_spin_lock_irqsave(&global_trace.start_lock, flags); + if (global_trace.stop_count++) goto out; - buffer = global_trace.buffer; + /* Prevent the buffers from switching */ + arch_spin_lock(&global_trace.max_lock); + + buffer = global_trace.trace_buffer.buffer; + if (buffer) + ring_buffer_record_disable(buffer); + +#ifdef CONFIG_TRACER_MAX_TRACE + buffer = global_trace.max_buffer.buffer; if (buffer) ring_buffer_record_disable(buffer); +#endif + + arch_spin_unlock(&global_trace.max_lock); - buffer = max_tr.buffer; + out: + raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); +} + +static void tracing_stop_tr(struct trace_array *tr) +{ + struct ring_buffer *buffer; + unsigned long flags; + + /* If global, we need to also stop the max tracer */ + if (tr->flags & TRACE_ARRAY_FL_GLOBAL) + return tracing_stop(); + + raw_spin_lock_irqsave(&tr->start_lock, flags); + if (tr->stop_count++) + goto out; + + buffer = tr->trace_buffer.buffer; if (buffer) ring_buffer_record_disable(buffer); out: - spin_unlock_irqrestore(&tracing_start_lock, flags); + raw_spin_unlock_irqrestore(&tr->start_lock, flags); } void trace_stop_cmdline_recording(void); -static void trace_save_cmdline(struct task_struct *tsk) +static int trace_save_cmdline(struct task_struct *tsk) { unsigned pid, idx; if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) - return; + return 0; /* * It's not the end of the world if we don't get @@ -765,12 +1515,12 @@ static void trace_save_cmdline(struct task_struct *tsk) * nor do we want to disable interrupts, * so if we miss here, then better luck next time. */ - if (!__raw_spin_trylock(&trace_cmdline_lock)) - return; + if (!arch_spin_trylock(&trace_cmdline_lock)) + return 0; - idx = map_pid_to_cmdline[tsk->pid]; + idx = savedcmd->map_pid_to_cmdline[tsk->pid]; if (idx == NO_CMDLINE_MAP) { - idx = (cmdline_idx + 1) % SAVED_CMDLINES; + idx = (savedcmd->cmdline_idx + 1) % savedcmd->cmdline_num; /* * Check whether the cmdline buffer at idx has a pid @@ -778,22 +1528,24 @@ static void trace_save_cmdline(struct task_struct *tsk) * need to clear the map_pid_to_cmdline. Otherwise we * would read the new comm for the old pid. */ - pid = map_cmdline_to_pid[idx]; + pid = savedcmd->map_cmdline_to_pid[idx]; if (pid != NO_CMDLINE_MAP) - map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; + savedcmd->map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; - map_cmdline_to_pid[idx] = tsk->pid; - map_pid_to_cmdline[tsk->pid] = idx; + savedcmd->map_cmdline_to_pid[idx] = tsk->pid; + savedcmd->map_pid_to_cmdline[tsk->pid] = idx; - cmdline_idx = idx; + savedcmd->cmdline_idx = idx; } - memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); + set_cmdline(idx, tsk->comm); + + arch_spin_unlock(&trace_cmdline_lock); - __raw_spin_unlock(&trace_cmdline_lock); + return 1; } -void trace_find_cmdline(int pid, char comm[]) +static void __trace_find_cmdline(int pid, char comm[]) { unsigned map; @@ -802,30 +1554,44 @@ void trace_find_cmdline(int pid, char comm[]) return; } + if (WARN_ON_ONCE(pid < 0)) { + strcpy(comm, "<XXX>"); + return; + } + if (pid > PID_MAX_DEFAULT) { strcpy(comm, "<...>"); return; } - preempt_disable(); - __raw_spin_lock(&trace_cmdline_lock); - map = map_pid_to_cmdline[pid]; + map = savedcmd->map_pid_to_cmdline[pid]; if (map != NO_CMDLINE_MAP) - strcpy(comm, saved_cmdlines[map]); + strcpy(comm, get_saved_cmdlines(map)); else strcpy(comm, "<...>"); +} + +void trace_find_cmdline(int pid, char comm[]) +{ + preempt_disable(); + arch_spin_lock(&trace_cmdline_lock); - __raw_spin_unlock(&trace_cmdline_lock); + __trace_find_cmdline(pid, comm); + + arch_spin_unlock(&trace_cmdline_lock); preempt_enable(); } void tracing_record_cmdline(struct task_struct *tsk) { - if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || - !tracing_is_on()) + if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) + return; + + if (!__this_cpu_read(trace_cmdline_save)) return; - trace_save_cmdline(tsk); + if (trace_save_cmdline(tsk)) + __this_cpu_write(trace_cmdline_save, false); } void @@ -836,7 +1602,6 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, entry->preempt_count = pc & 0xff; entry->pid = (tsk) ? tsk->pid : 0; - entry->tgid = (tsk) ? tsk->tgid : 0; entry->flags = #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | @@ -845,17 +1610,20 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, #endif ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | - (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); + (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) | + (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0); } +EXPORT_SYMBOL_GPL(tracing_generic_entry_update); -struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr, - int type, - unsigned long len, - unsigned long flags, int pc) +struct ring_buffer_event * +trace_buffer_lock_reserve(struct ring_buffer *buffer, + int type, + unsigned long len, + unsigned long flags, int pc) { struct ring_buffer_event *event; - event = ring_buffer_lock_reserve(tr->buffer, len); + event = ring_buffer_lock_reserve(buffer, len); if (event != NULL) { struct trace_entry *ent = ring_buffer_event_data(event); @@ -865,58 +1633,96 @@ struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr, return event; } -static void ftrace_trace_stack(struct trace_array *tr, - unsigned long flags, int skip, int pc); -static void ftrace_trace_userstack(struct trace_array *tr, - unsigned long flags, int pc); -static inline void __trace_buffer_unlock_commit(struct trace_array *tr, - struct ring_buffer_event *event, - unsigned long flags, int pc, - int wake) +void +__buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) { - ring_buffer_unlock_commit(tr->buffer, event); + __this_cpu_write(trace_cmdline_save, true); + ring_buffer_unlock_commit(buffer, event); +} - ftrace_trace_stack(tr, flags, 6, pc); - ftrace_trace_userstack(tr, flags, pc); +static inline void +__trace_buffer_unlock_commit(struct ring_buffer *buffer, + struct ring_buffer_event *event, + unsigned long flags, int pc) +{ + __buffer_unlock_commit(buffer, event); - if (wake) - trace_wake_up(); + ftrace_trace_stack(buffer, flags, 6, pc); + ftrace_trace_userstack(buffer, flags, pc); } -void trace_buffer_unlock_commit(struct trace_array *tr, - struct ring_buffer_event *event, - unsigned long flags, int pc) +void trace_buffer_unlock_commit(struct ring_buffer *buffer, + struct ring_buffer_event *event, + unsigned long flags, int pc) { - __trace_buffer_unlock_commit(tr, event, flags, pc, 1); + __trace_buffer_unlock_commit(buffer, event, flags, pc); +} +EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); + +static struct ring_buffer *temp_buffer; + +struct ring_buffer_event * +trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, + struct ftrace_event_file *ftrace_file, + int type, unsigned long len, + unsigned long flags, int pc) +{ + struct ring_buffer_event *entry; + + *current_rb = ftrace_file->tr->trace_buffer.buffer; + entry = trace_buffer_lock_reserve(*current_rb, + type, len, flags, pc); + /* + * If tracing is off, but we have triggers enabled + * we still need to look at the event data. Use the temp_buffer + * to store the trace event for the tigger to use. It's recusive + * safe and will not be recorded anywhere. + */ + if (!entry && ftrace_file->flags & FTRACE_EVENT_FL_TRIGGER_COND) { + *current_rb = temp_buffer; + entry = trace_buffer_lock_reserve(*current_rb, + type, len, flags, pc); + } + return entry; } +EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); struct ring_buffer_event * -trace_current_buffer_lock_reserve(int type, unsigned long len, +trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, + int type, unsigned long len, unsigned long flags, int pc) { - return trace_buffer_lock_reserve(&global_trace, + *current_rb = global_trace.trace_buffer.buffer; + return trace_buffer_lock_reserve(*current_rb, type, len, flags, pc); } EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); -void trace_current_buffer_unlock_commit(struct ring_buffer_event *event, +void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, + struct ring_buffer_event *event, unsigned long flags, int pc) { - __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 1); + __trace_buffer_unlock_commit(buffer, event, flags, pc); } EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); -void trace_nowake_buffer_unlock_commit(struct ring_buffer_event *event, - unsigned long flags, int pc) +void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, + struct ring_buffer_event *event, + unsigned long flags, int pc, + struct pt_regs *regs) { - __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 0); + __buffer_unlock_commit(buffer, event); + + ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); + ftrace_trace_userstack(buffer, flags, pc); } -EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); +EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); -void trace_current_buffer_discard_commit(struct ring_buffer_event *event) +void trace_current_buffer_discard_commit(struct ring_buffer *buffer, + struct ring_buffer_event *event) { - ring_buffer_discard_commit(global_trace.buffer, event); + ring_buffer_discard_commit(buffer, event); } EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); @@ -926,14 +1732,15 @@ trace_function(struct trace_array *tr, int pc) { struct ftrace_event_call *call = &event_function; + struct ring_buffer *buffer = tr->trace_buffer.buffer; struct ring_buffer_event *event; struct ftrace_entry *entry; /* If we are reading the ring buffer, don't trace */ - if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) + if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) return; - event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry), + event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), flags, pc); if (!event) return; @@ -941,116 +1748,152 @@ trace_function(struct trace_array *tr, entry->ip = ip; entry->parent_ip = parent_ip; - if (!filter_check_discard(call, entry, tr->buffer, event)) - ring_buffer_unlock_commit(tr->buffer, event); + if (!call_filter_check_discard(call, entry, buffer, event)) + __buffer_unlock_commit(buffer, event); } -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -static int __trace_graph_entry(struct trace_array *tr, - struct ftrace_graph_ent *trace, - unsigned long flags, - int pc) +#ifdef CONFIG_STACKTRACE + +#define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) +struct ftrace_stack { + unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; +}; + +static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); +static DEFINE_PER_CPU(int, ftrace_stack_reserve); + +static void __ftrace_trace_stack(struct ring_buffer *buffer, + unsigned long flags, + int skip, int pc, struct pt_regs *regs) { - struct ftrace_event_call *call = &event_funcgraph_entry; + struct ftrace_event_call *call = &event_kernel_stack; struct ring_buffer_event *event; - struct ftrace_graph_ent_entry *entry; + struct stack_entry *entry; + struct stack_trace trace; + int use_stack; + int size = FTRACE_STACK_ENTRIES; - if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) - return 0; + trace.nr_entries = 0; + trace.skip = skip; - event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_ENT, - sizeof(*entry), flags, pc); - if (!event) - return 0; - entry = ring_buffer_event_data(event); - entry->graph_ent = *trace; - if (!filter_current_check_discard(call, entry, event)) - ring_buffer_unlock_commit(global_trace.buffer, event); + /* + * Since events can happen in NMIs there's no safe way to + * use the per cpu ftrace_stacks. We reserve it and if an interrupt + * or NMI comes in, it will just have to use the default + * FTRACE_STACK_SIZE. + */ + preempt_disable_notrace(); - return 1; -} + use_stack = __this_cpu_inc_return(ftrace_stack_reserve); + /* + * We don't need any atomic variables, just a barrier. + * If an interrupt comes in, we don't care, because it would + * have exited and put the counter back to what we want. + * We just need a barrier to keep gcc from moving things + * around. + */ + barrier(); + if (use_stack == 1) { + trace.entries = this_cpu_ptr(ftrace_stack.calls); + trace.max_entries = FTRACE_STACK_MAX_ENTRIES; -static void __trace_graph_return(struct trace_array *tr, - struct ftrace_graph_ret *trace, - unsigned long flags, - int pc) -{ - struct ftrace_event_call *call = &event_funcgraph_exit; - struct ring_buffer_event *event; - struct ftrace_graph_ret_entry *entry; + if (regs) + save_stack_trace_regs(regs, &trace); + else + save_stack_trace(&trace); - if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) - return; + if (trace.nr_entries > size) + size = trace.nr_entries; + } else + /* From now on, use_stack is a boolean */ + use_stack = 0; - event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_RET, - sizeof(*entry), flags, pc); + size *= sizeof(unsigned long); + + event = trace_buffer_lock_reserve(buffer, TRACE_STACK, + sizeof(*entry) + size, flags, pc); if (!event) - return; - entry = ring_buffer_event_data(event); - entry->ret = *trace; - if (!filter_current_check_discard(call, entry, event)) - ring_buffer_unlock_commit(global_trace.buffer, event); -} -#endif + goto out; + entry = ring_buffer_event_data(event); + + memset(&entry->caller, 0, size); + + if (use_stack) + memcpy(&entry->caller, trace.entries, + trace.nr_entries * sizeof(unsigned long)); + else { + trace.max_entries = FTRACE_STACK_ENTRIES; + trace.entries = entry->caller; + if (regs) + save_stack_trace_regs(regs, &trace); + else + save_stack_trace(&trace); + } + + entry->size = trace.nr_entries; + + if (!call_filter_check_discard(call, entry, buffer, event)) + __buffer_unlock_commit(buffer, event); + + out: + /* Again, don't let gcc optimize things here */ + barrier(); + __this_cpu_dec(ftrace_stack_reserve); + preempt_enable_notrace(); -void -ftrace(struct trace_array *tr, struct trace_array_cpu *data, - unsigned long ip, unsigned long parent_ip, unsigned long flags, - int pc) -{ - if (likely(!atomic_read(&data->disabled))) - trace_function(tr, ip, parent_ip, flags, pc); } -static void __ftrace_trace_stack(struct trace_array *tr, - unsigned long flags, - int skip, int pc) +void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, + int skip, int pc, struct pt_regs *regs) { -#ifdef CONFIG_STACKTRACE - struct ftrace_event_call *call = &event_kernel_stack; - struct ring_buffer_event *event; - struct stack_entry *entry; - struct stack_trace trace; - - event = trace_buffer_lock_reserve(tr, TRACE_STACK, - sizeof(*entry), flags, pc); - if (!event) + if (!(trace_flags & TRACE_ITER_STACKTRACE)) return; - entry = ring_buffer_event_data(event); - memset(&entry->caller, 0, sizeof(entry->caller)); - trace.nr_entries = 0; - trace.max_entries = FTRACE_STACK_ENTRIES; - trace.skip = skip; - trace.entries = entry->caller; - - save_stack_trace(&trace); - if (!filter_check_discard(call, entry, tr->buffer, event)) - ring_buffer_unlock_commit(tr->buffer, event); -#endif + __ftrace_trace_stack(buffer, flags, skip, pc, regs); } -static void ftrace_trace_stack(struct trace_array *tr, - unsigned long flags, - int skip, int pc) +void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, + int skip, int pc) { if (!(trace_flags & TRACE_ITER_STACKTRACE)) return; - __ftrace_trace_stack(tr, flags, skip, pc); + __ftrace_trace_stack(buffer, flags, skip, pc, NULL); } -void __trace_stack(struct trace_array *tr, - unsigned long flags, - int skip, int pc) +void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, + int pc) { - __ftrace_trace_stack(tr, flags, skip, pc); + __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); } -static void ftrace_trace_userstack(struct trace_array *tr, - unsigned long flags, int pc) +/** + * trace_dump_stack - record a stack back trace in the trace buffer + * @skip: Number of functions to skip (helper handlers) + */ +void trace_dump_stack(int skip) +{ + unsigned long flags; + + if (tracing_disabled || tracing_selftest_running) + return; + + local_save_flags(flags); + + /* + * Skip 3 more, seems to get us at the caller of + * this function. + */ + skip += 3; + __ftrace_trace_stack(global_trace.trace_buffer.buffer, + flags, skip, preempt_count(), NULL); +} + +static DEFINE_PER_CPU(int, user_stack_count); + +void +ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) { -#ifdef CONFIG_STACKTRACE struct ftrace_event_call *call = &event_user_stack; struct ring_buffer_event *event; struct userstack_entry *entry; @@ -1059,12 +1902,30 @@ static void ftrace_trace_userstack(struct trace_array *tr, if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) return; - event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK, + /* + * NMIs can not handle page faults, even with fix ups. + * The save user stack can (and often does) fault. + */ + if (unlikely(in_nmi())) + return; + + /* + * prevent recursion, since the user stack tracing may + * trigger other kernel events. + */ + preempt_disable(); + if (__this_cpu_read(user_stack_count)) + goto out; + + __this_cpu_inc(user_stack_count); + + event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, sizeof(*entry), flags, pc); if (!event) - return; + goto out_drop_count; entry = ring_buffer_event_data(event); + entry->tgid = current->tgid; memset(&entry->caller, 0, sizeof(entry->caller)); trace.nr_entries = 0; @@ -1073,9 +1934,13 @@ static void ftrace_trace_userstack(struct trace_array *tr, trace.entries = entry->caller; save_stack_trace_user(&trace); - if (!filter_check_discard(call, entry, tr->buffer, event)) - ring_buffer_unlock_commit(tr->buffer, event); -#endif + if (!call_filter_check_discard(call, entry, buffer, event)) + __buffer_unlock_commit(buffer, event); + + out_drop_count: + __this_cpu_dec(user_stack_count); + out: + preempt_enable(); } #ifdef UNUSED @@ -1085,174 +1950,148 @@ static void __trace_userstack(struct trace_array *tr, unsigned long flags) } #endif /* UNUSED */ -static void -ftrace_trace_special(void *__tr, - unsigned long arg1, unsigned long arg2, unsigned long arg3, - int pc) -{ - struct ring_buffer_event *event; - struct trace_array *tr = __tr; - struct special_entry *entry; +#endif /* CONFIG_STACKTRACE */ - event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL, - sizeof(*entry), 0, pc); - if (!event) - return; - entry = ring_buffer_event_data(event); - entry->arg1 = arg1; - entry->arg2 = arg2; - entry->arg3 = arg3; - trace_buffer_unlock_commit(tr, event, 0, pc); -} +/* created for use with alloc_percpu */ +struct trace_buffer_struct { + char buffer[TRACE_BUF_SIZE]; +}; -void -__trace_special(void *__tr, void *__data, - unsigned long arg1, unsigned long arg2, unsigned long arg3) -{ - ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); -} +static struct trace_buffer_struct *trace_percpu_buffer; +static struct trace_buffer_struct *trace_percpu_sirq_buffer; +static struct trace_buffer_struct *trace_percpu_irq_buffer; +static struct trace_buffer_struct *trace_percpu_nmi_buffer; -void -tracing_sched_switch_trace(struct trace_array *tr, - struct task_struct *prev, - struct task_struct *next, - unsigned long flags, int pc) +/* + * The buffer used is dependent on the context. There is a per cpu + * buffer for normal context, softirq contex, hard irq context and + * for NMI context. Thise allows for lockless recording. + * + * Note, if the buffers failed to be allocated, then this returns NULL + */ +static char *get_trace_buf(void) { - struct ftrace_event_call *call = &event_context_switch; - struct ring_buffer_event *event; - struct ctx_switch_entry *entry; + struct trace_buffer_struct *percpu_buffer; - event = trace_buffer_lock_reserve(tr, TRACE_CTX, - sizeof(*entry), flags, pc); - if (!event) - return; - entry = ring_buffer_event_data(event); - entry->prev_pid = prev->pid; - entry->prev_prio = prev->prio; - entry->prev_state = prev->state; - entry->next_pid = next->pid; - entry->next_prio = next->prio; - entry->next_state = next->state; - entry->next_cpu = task_cpu(next); + /* + * If we have allocated per cpu buffers, then we do not + * need to do any locking. + */ + if (in_nmi()) + percpu_buffer = trace_percpu_nmi_buffer; + else if (in_irq()) + percpu_buffer = trace_percpu_irq_buffer; + else if (in_softirq()) + percpu_buffer = trace_percpu_sirq_buffer; + else + percpu_buffer = trace_percpu_buffer; + + if (!percpu_buffer) + return NULL; - if (!filter_check_discard(call, entry, tr->buffer, event)) - trace_buffer_unlock_commit(tr, event, flags, pc); + return this_cpu_ptr(&percpu_buffer->buffer[0]); } -void -tracing_sched_wakeup_trace(struct trace_array *tr, - struct task_struct *wakee, - struct task_struct *curr, - unsigned long flags, int pc) +static int alloc_percpu_trace_buffer(void) { - struct ftrace_event_call *call = &event_wakeup; - struct ring_buffer_event *event; - struct ctx_switch_entry *entry; + struct trace_buffer_struct *buffers; + struct trace_buffer_struct *sirq_buffers; + struct trace_buffer_struct *irq_buffers; + struct trace_buffer_struct *nmi_buffers; - event = trace_buffer_lock_reserve(tr, TRACE_WAKE, - sizeof(*entry), flags, pc); - if (!event) - return; - entry = ring_buffer_event_data(event); - entry->prev_pid = curr->pid; - entry->prev_prio = curr->prio; - entry->prev_state = curr->state; - entry->next_pid = wakee->pid; - entry->next_prio = wakee->prio; - entry->next_state = wakee->state; - entry->next_cpu = task_cpu(wakee); + buffers = alloc_percpu(struct trace_buffer_struct); + if (!buffers) + goto err_warn; - if (!filter_check_discard(call, entry, tr->buffer, event)) - ring_buffer_unlock_commit(tr->buffer, event); - ftrace_trace_stack(tr, flags, 6, pc); - ftrace_trace_userstack(tr, flags, pc); -} + sirq_buffers = alloc_percpu(struct trace_buffer_struct); + if (!sirq_buffers) + goto err_sirq; -void -ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) -{ - struct trace_array *tr = &global_trace; - struct trace_array_cpu *data; - unsigned long flags; - int cpu; - int pc; + irq_buffers = alloc_percpu(struct trace_buffer_struct); + if (!irq_buffers) + goto err_irq; - if (tracing_disabled) - return; + nmi_buffers = alloc_percpu(struct trace_buffer_struct); + if (!nmi_buffers) + goto err_nmi; - pc = preempt_count(); - local_irq_save(flags); - cpu = raw_smp_processor_id(); - data = tr->data[cpu]; + trace_percpu_buffer = buffers; + trace_percpu_sirq_buffer = sirq_buffers; + trace_percpu_irq_buffer = irq_buffers; + trace_percpu_nmi_buffer = nmi_buffers; - if (likely(atomic_inc_return(&data->disabled) == 1)) - ftrace_trace_special(tr, arg1, arg2, arg3, pc); + return 0; - atomic_dec(&data->disabled); - local_irq_restore(flags); + err_nmi: + free_percpu(irq_buffers); + err_irq: + free_percpu(sirq_buffers); + err_sirq: + free_percpu(buffers); + err_warn: + WARN(1, "Could not allocate percpu trace_printk buffer"); + return -ENOMEM; } -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -int trace_graph_entry(struct ftrace_graph_ent *trace) +static int buffers_allocated; + +void trace_printk_init_buffers(void) { - struct trace_array *tr = &global_trace; - struct trace_array_cpu *data; - unsigned long flags; - long disabled; - int ret; - int cpu; - int pc; + if (buffers_allocated) + return; - if (!ftrace_trace_task(current)) - return 0; + if (alloc_percpu_trace_buffer()) + return; - if (!ftrace_graph_addr(trace->func)) - return 0; + /* trace_printk() is for debug use only. Don't use it in production. */ - local_irq_save(flags); - cpu = raw_smp_processor_id(); - data = tr->data[cpu]; - disabled = atomic_inc_return(&data->disabled); - if (likely(disabled == 1)) { - pc = preempt_count(); - ret = __trace_graph_entry(tr, trace, flags, pc); - } else { - ret = 0; - } - /* Only do the atomic if it is not already set */ - if (!test_tsk_trace_graph(current)) - set_tsk_trace_graph(current); + pr_warning("\n**********************************************************\n"); + pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); + pr_warning("** **\n"); + pr_warning("** trace_printk() being used. Allocating extra memory. **\n"); + pr_warning("** **\n"); + pr_warning("** This means that this is a DEBUG kernel and it is **\n"); + pr_warning("** unsafe for produciton use. **\n"); + pr_warning("** **\n"); + pr_warning("** If you see this message and you are not debugging **\n"); + pr_warning("** the kernel, report this immediately to your vendor! **\n"); + pr_warning("** **\n"); + pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); + pr_warning("**********************************************************\n"); - atomic_dec(&data->disabled); - local_irq_restore(flags); + /* Expand the buffers to set size */ + tracing_update_buffers(); - return ret; + buffers_allocated = 1; + + /* + * trace_printk_init_buffers() can be called by modules. + * If that happens, then we need to start cmdline recording + * directly here. If the global_trace.buffer is already + * allocated here, then this was called by module code. + */ + if (global_trace.trace_buffer.buffer) + tracing_start_cmdline_record(); } -void trace_graph_return(struct ftrace_graph_ret *trace) +void trace_printk_start_comm(void) { - struct trace_array *tr = &global_trace; - struct trace_array_cpu *data; - unsigned long flags; - long disabled; - int cpu; - int pc; - - local_irq_save(flags); - cpu = raw_smp_processor_id(); - data = tr->data[cpu]; - disabled = atomic_inc_return(&data->disabled); - if (likely(disabled == 1)) { - pc = preempt_count(); - __trace_graph_return(tr, trace, flags, pc); - } - if (!trace->depth) - clear_tsk_trace_graph(current); - atomic_dec(&data->disabled); - local_irq_restore(flags); + /* Start tracing comms if trace printk is set */ + if (!buffers_allocated) + return; + tracing_start_cmdline_record(); } -#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ +static void trace_printk_start_stop_comm(int enabled) +{ + if (!buffers_allocated) + return; + + if (enabled) + tracing_start_cmdline_record(); + else + tracing_stop_cmdline_record(); +} /** * trace_vbprintk - write binary msg to tracing buffer @@ -1260,19 +2099,14 @@ void trace_graph_return(struct ftrace_graph_ret *trace) */ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) { - static raw_spinlock_t trace_buf_lock = - (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; - static u32 trace_buf[TRACE_BUF_SIZE]; - struct ftrace_event_call *call = &event_bprint; struct ring_buffer_event *event; + struct ring_buffer *buffer; struct trace_array *tr = &global_trace; - struct trace_array_cpu *data; struct bprint_entry *entry; unsigned long flags; - int disable; - int resched; - int cpu, len = 0, size, pc; + char *tbuffer; + int len = 0, size, pc; if (unlikely(tracing_selftest_running || tracing_disabled)) return 0; @@ -1281,159 +2115,190 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) pause_graph_tracing(); pc = preempt_count(); - resched = ftrace_preempt_disable(); - cpu = raw_smp_processor_id(); - data = tr->data[cpu]; + preempt_disable_notrace(); - disable = atomic_inc_return(&data->disabled); - if (unlikely(disable != 1)) + tbuffer = get_trace_buf(); + if (!tbuffer) { + len = 0; goto out; + } - /* Lockdep uses trace_printk for lock tracing */ - local_irq_save(flags); - __raw_spin_lock(&trace_buf_lock); - len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); + len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); - if (len > TRACE_BUF_SIZE || len < 0) - goto out_unlock; + if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) + goto out; + local_save_flags(flags); size = sizeof(*entry) + sizeof(u32) * len; - event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc); + buffer = tr->trace_buffer.buffer; + event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, + flags, pc); if (!event) - goto out_unlock; + goto out; entry = ring_buffer_event_data(event); entry->ip = ip; entry->fmt = fmt; - memcpy(entry->buf, trace_buf, sizeof(u32) * len); - if (!filter_check_discard(call, entry, tr->buffer, event)) - ring_buffer_unlock_commit(tr->buffer, event); - -out_unlock: - __raw_spin_unlock(&trace_buf_lock); - local_irq_restore(flags); + memcpy(entry->buf, tbuffer, sizeof(u32) * len); + if (!call_filter_check_discard(call, entry, buffer, event)) { + __buffer_unlock_commit(buffer, event); + ftrace_trace_stack(buffer, flags, 6, pc); + } out: - atomic_dec_return(&data->disabled); - ftrace_preempt_enable(resched); + preempt_enable_notrace(); unpause_graph_tracing(); return len; } EXPORT_SYMBOL_GPL(trace_vbprintk); -int trace_vprintk(unsigned long ip, const char *fmt, va_list args) +static int +__trace_array_vprintk(struct ring_buffer *buffer, + unsigned long ip, const char *fmt, va_list args) { - static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; - static char trace_buf[TRACE_BUF_SIZE]; - struct ftrace_event_call *call = &event_print; struct ring_buffer_event *event; - struct trace_array *tr = &global_trace; - struct trace_array_cpu *data; - int cpu, len = 0, size, pc; + int len = 0, size, pc; struct print_entry *entry; - unsigned long irq_flags; - int disable; + unsigned long flags; + char *tbuffer; if (tracing_disabled || tracing_selftest_running) return 0; + /* Don't pollute graph traces with trace_vprintk internals */ + pause_graph_tracing(); + pc = preempt_count(); preempt_disable_notrace(); - cpu = raw_smp_processor_id(); - data = tr->data[cpu]; - disable = atomic_inc_return(&data->disabled); - if (unlikely(disable != 1)) - goto out; - pause_graph_tracing(); - raw_local_irq_save(irq_flags); - __raw_spin_lock(&trace_buf_lock); - len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); + tbuffer = get_trace_buf(); + if (!tbuffer) { + len = 0; + goto out; + } - len = min(len, TRACE_BUF_SIZE-1); - trace_buf[len] = 0; + len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); + if (len > TRACE_BUF_SIZE) + goto out; + local_save_flags(flags); size = sizeof(*entry) + len + 1; - event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc); + event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, + flags, pc); if (!event) - goto out_unlock; + goto out; entry = ring_buffer_event_data(event); - entry->ip = ip; + entry->ip = ip; - memcpy(&entry->buf, trace_buf, len); - entry->buf[len] = 0; - if (!filter_check_discard(call, entry, tr->buffer, event)) - ring_buffer_unlock_commit(tr->buffer, event); - - out_unlock: - __raw_spin_unlock(&trace_buf_lock); - raw_local_irq_restore(irq_flags); - unpause_graph_tracing(); + memcpy(&entry->buf, tbuffer, len); + entry->buf[len] = '\0'; + if (!call_filter_check_discard(call, entry, buffer, event)) { + __buffer_unlock_commit(buffer, event); + ftrace_trace_stack(buffer, flags, 6, pc); + } out: - atomic_dec_return(&data->disabled); preempt_enable_notrace(); + unpause_graph_tracing(); return len; } -EXPORT_SYMBOL_GPL(trace_vprintk); -enum trace_file_type { - TRACE_FILE_LAT_FMT = 1, - TRACE_FILE_ANNOTATE = 2, -}; +int trace_array_vprintk(struct trace_array *tr, + unsigned long ip, const char *fmt, va_list args) +{ + return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); +} + +int trace_array_printk(struct trace_array *tr, + unsigned long ip, const char *fmt, ...) +{ + int ret; + va_list ap; + + if (!(trace_flags & TRACE_ITER_PRINTK)) + return 0; + + va_start(ap, fmt); + ret = trace_array_vprintk(tr, ip, fmt, ap); + va_end(ap); + return ret; +} + +int trace_array_printk_buf(struct ring_buffer *buffer, + unsigned long ip, const char *fmt, ...) +{ + int ret; + va_list ap; + + if (!(trace_flags & TRACE_ITER_PRINTK)) + return 0; + + va_start(ap, fmt); + ret = __trace_array_vprintk(buffer, ip, fmt, ap); + va_end(ap); + return ret; +} + +int trace_vprintk(unsigned long ip, const char *fmt, va_list args) +{ + return trace_array_vprintk(&global_trace, ip, fmt, args); +} +EXPORT_SYMBOL_GPL(trace_vprintk); static void trace_iterator_increment(struct trace_iterator *iter) { - /* Don't allow ftrace to trace into the ring buffers */ - ftrace_disable_cpu(); + struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); iter->idx++; - if (iter->buffer_iter[iter->cpu]) - ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); - - ftrace_enable_cpu(); + if (buf_iter) + ring_buffer_read(buf_iter, NULL); } static struct trace_entry * -peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) +peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, + unsigned long *lost_events) { struct ring_buffer_event *event; - struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; - - /* Don't allow ftrace to trace into the ring buffers */ - ftrace_disable_cpu(); + struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); if (buf_iter) event = ring_buffer_iter_peek(buf_iter, ts); else - event = ring_buffer_peek(iter->tr->buffer, cpu, ts); - - ftrace_enable_cpu(); + event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, + lost_events); - return event ? ring_buffer_event_data(event) : NULL; + if (event) { + iter->ent_size = ring_buffer_event_length(event); + return ring_buffer_event_data(event); + } + iter->ent_size = 0; + return NULL; } static struct trace_entry * -__find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) +__find_next_entry(struct trace_iterator *iter, int *ent_cpu, + unsigned long *missing_events, u64 *ent_ts) { - struct ring_buffer *buffer = iter->tr->buffer; + struct ring_buffer *buffer = iter->trace_buffer->buffer; struct trace_entry *ent, *next = NULL; + unsigned long lost_events = 0, next_lost = 0; int cpu_file = iter->cpu_file; u64 next_ts = 0, ts; int next_cpu = -1; + int next_size = 0; int cpu; /* * If we are in a per_cpu trace file, don't bother by iterating over * all cpu and peek directly. */ - if (cpu_file > TRACE_PIPE_ALL_CPU) { + if (cpu_file > RING_BUFFER_ALL_CPUS) { if (ring_buffer_empty_cpu(buffer, cpu_file)) return NULL; - ent = peek_next_entry(iter, cpu_file, ent_ts); + ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); if (ent_cpu) *ent_cpu = cpu_file; @@ -1445,7 +2310,7 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) if (ring_buffer_empty_cpu(buffer, cpu)) continue; - ent = peek_next_entry(iter, cpu, &ts); + ent = peek_next_entry(iter, cpu, &ts, &lost_events); /* * Pick the entry with the smallest timestamp: @@ -1454,15 +2319,22 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) next = ent; next_cpu = cpu; next_ts = ts; + next_lost = lost_events; + next_size = iter->ent_size; } } + iter->ent_size = next_size; + if (ent_cpu) *ent_cpu = next_cpu; if (ent_ts) *ent_ts = next_ts; + if (missing_events) + *missing_events = next_lost; + return next; } @@ -1470,13 +2342,14 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) { - return __find_next_entry(iter, ent_cpu, ent_ts); + return __find_next_entry(iter, ent_cpu, NULL, ent_ts); } /* Find the next real entry, and increment the iterator to the next entry */ -static void *find_next_entry_inc(struct trace_iterator *iter) +void *trace_find_next_entry_inc(struct trace_iterator *iter) { - iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); + iter->ent = __find_next_entry(iter, &iter->cpu, + &iter->lost_events, &iter->ts); if (iter->ent) trace_iterator_increment(iter); @@ -1486,10 +2359,8 @@ static void *find_next_entry_inc(struct trace_iterator *iter) static void trace_consume(struct trace_iterator *iter) { - /* Don't allow ftrace to trace into the ring buffers */ - ftrace_disable_cpu(); - ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); - ftrace_enable_cpu(); + ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, + &iter->lost_events); } static void *s_next(struct seq_file *m, void *v, loff_t *pos) @@ -1498,6 +2369,8 @@ static void *s_next(struct seq_file *m, void *v, loff_t *pos) int i = (int)*pos; void *ent; + WARN_ON_ONCE(iter->leftover); + (*pos)++; /* can't go backwards */ @@ -1505,81 +2378,157 @@ static void *s_next(struct seq_file *m, void *v, loff_t *pos) return NULL; if (iter->idx < 0) - ent = find_next_entry_inc(iter); + ent = trace_find_next_entry_inc(iter); else ent = iter; while (ent && iter->idx < i) - ent = find_next_entry_inc(iter); + ent = trace_find_next_entry_inc(iter); iter->pos = *pos; return ent; } +void tracing_iter_reset(struct trace_iterator *iter, int cpu) +{ + struct ring_buffer_event *event; + struct ring_buffer_iter *buf_iter; + unsigned long entries = 0; + u64 ts; + + per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; + + buf_iter = trace_buffer_iter(iter, cpu); + if (!buf_iter) + return; + + ring_buffer_iter_reset(buf_iter); + + /* + * We could have the case with the max latency tracers + * that a reset never took place on a cpu. This is evident + * by the timestamp being before the start of the buffer. + */ + while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { + if (ts >= iter->trace_buffer->time_start) + break; + entries++; + ring_buffer_read(buf_iter, NULL); + } + + per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; +} + /* - * No necessary locking here. The worst thing which can - * happen is loosing events consumed at the same time - * by a trace_pipe reader. - * Other than that, we don't risk to crash the ring buffer - * because it serializes the readers. - * * The current tracer is copied to avoid a global locking * all around. */ static void *s_start(struct seq_file *m, loff_t *pos) { struct trace_iterator *iter = m->private; - static struct tracer *old_tracer; + struct trace_array *tr = iter->tr; int cpu_file = iter->cpu_file; void *p = NULL; loff_t l = 0; int cpu; - /* copy the tracer to avoid using a global lock all around */ + /* + * copy the tracer to avoid using a global lock all around. + * iter->trace is a copy of current_trace, the pointer to the + * name may be used instead of a strcmp(), as iter->trace->name + * will point to the same string as current_trace->name. + */ mutex_lock(&trace_types_lock); - if (unlikely(old_tracer != current_trace && current_trace)) { - old_tracer = current_trace; - *iter->trace = *current_trace; - } + if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) + *iter->trace = *tr->current_trace; mutex_unlock(&trace_types_lock); - atomic_inc(&trace_record_cmdline_disabled); +#ifdef CONFIG_TRACER_MAX_TRACE + if (iter->snapshot && iter->trace->use_max_tr) + return ERR_PTR(-EBUSY); +#endif + + if (!iter->snapshot) + atomic_inc(&trace_record_cmdline_disabled); if (*pos != iter->pos) { iter->ent = NULL; iter->cpu = 0; iter->idx = -1; - ftrace_disable_cpu(); - - if (cpu_file == TRACE_PIPE_ALL_CPU) { + if (cpu_file == RING_BUFFER_ALL_CPUS) { for_each_tracing_cpu(cpu) - ring_buffer_iter_reset(iter->buffer_iter[cpu]); + tracing_iter_reset(iter, cpu); } else - ring_buffer_iter_reset(iter->buffer_iter[cpu_file]); - - - ftrace_enable_cpu(); + tracing_iter_reset(iter, cpu_file); + iter->leftover = 0; for (p = iter; p && l < *pos; p = s_next(m, p, &l)) ; } else { - l = *pos - 1; - p = s_next(m, p, &l); + /* + * If we overflowed the seq_file before, then we want + * to just reuse the trace_seq buffer again. + */ + if (iter->leftover) + p = iter; + else { + l = *pos - 1; + p = s_next(m, p, &l); + } } trace_event_read_lock(); + trace_access_lock(cpu_file); return p; } static void s_stop(struct seq_file *m, void *p) { - atomic_dec(&trace_record_cmdline_disabled); + struct trace_iterator *iter = m->private; + +#ifdef CONFIG_TRACER_MAX_TRACE + if (iter->snapshot && iter->trace->use_max_tr) + return; +#endif + + if (!iter->snapshot) + atomic_dec(&trace_record_cmdline_disabled); + + trace_access_unlock(iter->cpu_file); trace_event_read_unlock(); } +static void +get_total_entries(struct trace_buffer *buf, + unsigned long *total, unsigned long *entries) +{ + unsigned long count; + int cpu; + + *total = 0; + *entries = 0; + + for_each_tracing_cpu(cpu) { + count = ring_buffer_entries_cpu(buf->buffer, cpu); + /* + * If this buffer has skipped entries, then we hold all + * entries for the trace and we need to ignore the + * ones before the time stamp. + */ + if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { + count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; + /* total is the same as the entries */ + *total += count; + } else + *total += count + + ring_buffer_overrun_cpu(buf->buffer, cpu); + *entries += count; + } +} + static void print_lat_help_header(struct seq_file *m) { seq_puts(m, "# _------=> CPU# \n"); @@ -1587,36 +2536,55 @@ static void print_lat_help_header(struct seq_file *m) seq_puts(m, "# | / _----=> need-resched \n"); seq_puts(m, "# || / _---=> hardirq/softirq \n"); seq_puts(m, "# ||| / _--=> preempt-depth \n"); - seq_puts(m, "# |||| / \n"); - seq_puts(m, "# ||||| delay \n"); + seq_puts(m, "# |||| / delay \n"); seq_puts(m, "# cmd pid ||||| time | caller \n"); - seq_puts(m, "# \\ / ||||| \\ | / \n"); + seq_puts(m, "# \\ / ||||| \\ | / \n"); +} + +static void print_event_info(struct trace_buffer *buf, struct seq_file *m) +{ + unsigned long total; + unsigned long entries; + + get_total_entries(buf, &total, &entries); + seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", + entries, total, num_online_cpus()); + seq_puts(m, "#\n"); } -static void print_func_help_header(struct seq_file *m) +static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) { - seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); + print_event_info(buf, m); + seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); seq_puts(m, "# | | | | |\n"); } +static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) +{ + print_event_info(buf, m); + seq_puts(m, "# _-----=> irqs-off\n"); + seq_puts(m, "# / _----=> need-resched\n"); + seq_puts(m, "# | / _---=> hardirq/softirq\n"); + seq_puts(m, "# || / _--=> preempt-depth\n"); + seq_puts(m, "# ||| / delay\n"); + seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); + seq_puts(m, "# | | | |||| | |\n"); +} -static void +void print_trace_header(struct seq_file *m, struct trace_iterator *iter) { unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); - struct trace_array *tr = iter->tr; - struct trace_array_cpu *data = tr->data[tr->cpu]; - struct tracer *type = current_trace; - unsigned long total; + struct trace_buffer *buf = iter->trace_buffer; + struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); + struct tracer *type = iter->trace; unsigned long entries; + unsigned long total; const char *name = "preemption"; - if (type) - name = type->name; + name = type->name; - entries = ring_buffer_entries(iter->tr->buffer); - total = entries + - ring_buffer_overruns(iter->tr->buffer); + get_total_entries(buf, &total, &entries); seq_printf(m, "# %s latency trace v1.1.5 on %s\n", name, UTS_RELEASE); @@ -1627,7 +2595,7 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter) nsecs_to_usecs(data->saved_latency), entries, total, - tr->cpu, + buf->cpu, #if defined(CONFIG_PREEMPT_NONE) "server", #elif defined(CONFIG_PREEMPT_VOLUNTARY) @@ -1647,7 +2615,8 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter) seq_puts(m, "# -----------------\n"); seq_printf(m, "# | task: %.16s-%d " "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", - data->comm, data->pid, data->uid, data->nice, + data->comm, data->pid, + from_kuid_munged(seq_user_ns(m), data->uid), data->nice, data->policy, data->rt_priority); seq_puts(m, "# -----------------\n"); @@ -1658,7 +2627,7 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter) seq_puts(m, "\n# => ended at: "); seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); trace_print_seq(m, &iter->seq); - seq_puts(m, "#\n"); + seq_puts(m, "\n#\n"); } seq_puts(m, "#\n"); @@ -1677,6 +2646,9 @@ static void test_cpu_buff_start(struct trace_iterator *iter) if (cpumask_test_cpu(iter->cpu, iter->started)) return; + if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) + return; + cpumask_set_cpu(iter->cpu, iter->started); /* Don't print started cpu buffer for the first entry of the trace */ @@ -1709,7 +2681,7 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter) } if (event) - return event->trace(iter, sym_flags); + return event->funcs->trace(iter, sym_flags, event); if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) goto partial; @@ -1735,7 +2707,7 @@ static enum print_line_t print_raw_fmt(struct trace_iterator *iter) event = ftrace_find_event(entry->type); if (event) - return event->raw(iter, 0); + return event->funcs->raw(iter, 0, event); if (!trace_seq_printf(s, "%d ?\n", entry->type)) goto partial; @@ -1762,7 +2734,7 @@ static enum print_line_t print_hex_fmt(struct trace_iterator *iter) event = ftrace_find_event(entry->type); if (event) { - enum print_line_t ret = event->hex(iter, 0); + enum print_line_t ret = event->funcs->hex(iter, 0, event); if (ret != TRACE_TYPE_HANDLED) return ret; } @@ -1787,32 +2759,36 @@ static enum print_line_t print_bin_fmt(struct trace_iterator *iter) } event = ftrace_find_event(entry->type); - return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; + return event ? event->funcs->binary(iter, 0, event) : + TRACE_TYPE_HANDLED; } -static int trace_empty(struct trace_iterator *iter) +int trace_empty(struct trace_iterator *iter) { + struct ring_buffer_iter *buf_iter; int cpu; /* If we are looking at one CPU buffer, only check that one */ - if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { + if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { cpu = iter->cpu_file; - if (iter->buffer_iter[cpu]) { - if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) + buf_iter = trace_buffer_iter(iter, cpu); + if (buf_iter) { + if (!ring_buffer_iter_empty(buf_iter)) return 0; } else { - if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) + if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) return 0; } return 1; } for_each_tracing_cpu(cpu) { - if (iter->buffer_iter[cpu]) { - if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) + buf_iter = trace_buffer_iter(iter, cpu); + if (buf_iter) { + if (!ring_buffer_iter_empty(buf_iter)) return 0; } else { - if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) + if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) return 0; } } @@ -1821,16 +2797,26 @@ static int trace_empty(struct trace_iterator *iter) } /* Called with trace_event_read_lock() held. */ -static enum print_line_t print_trace_line(struct trace_iterator *iter) +enum print_line_t print_trace_line(struct trace_iterator *iter) { enum print_line_t ret; + if (iter->lost_events && + !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", + iter->cpu, iter->lost_events)) + return TRACE_TYPE_PARTIAL_LINE; + if (iter->trace && iter->trace->print_line) { ret = iter->trace->print_line(iter); if (ret != TRACE_TYPE_UNHANDLED) return ret; } + if (iter->ent->type == TRACE_BPUTS && + trace_flags & TRACE_ITER_PRINTK && + trace_flags & TRACE_ITER_PRINTK_MSGONLY) + return trace_print_bputs_msg_only(iter); + if (iter->ent->type == TRACE_BPRINT && trace_flags & TRACE_ITER_PRINTK && trace_flags & TRACE_ITER_PRINTK_MSGONLY) @@ -1853,37 +2839,153 @@ static enum print_line_t print_trace_line(struct trace_iterator *iter) return print_trace_fmt(iter); } +void trace_latency_header(struct seq_file *m) +{ + struct trace_iterator *iter = m->private; + + /* print nothing if the buffers are empty */ + if (trace_empty(iter)) + return; + + if (iter->iter_flags & TRACE_FILE_LAT_FMT) + print_trace_header(m, iter); + + if (!(trace_flags & TRACE_ITER_VERBOSE)) + print_lat_help_header(m); +} + +void trace_default_header(struct seq_file *m) +{ + struct trace_iterator *iter = m->private; + + if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) + return; + + if (iter->iter_flags & TRACE_FILE_LAT_FMT) { + /* print nothing if the buffers are empty */ + if (trace_empty(iter)) + return; + print_trace_header(m, iter); + if (!(trace_flags & TRACE_ITER_VERBOSE)) + print_lat_help_header(m); + } else { + if (!(trace_flags & TRACE_ITER_VERBOSE)) { + if (trace_flags & TRACE_ITER_IRQ_INFO) + print_func_help_header_irq(iter->trace_buffer, m); + else + print_func_help_header(iter->trace_buffer, m); + } + } +} + +static void test_ftrace_alive(struct seq_file *m) +{ + if (!ftrace_is_dead()) + return; + seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"); + seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n"); +} + +#ifdef CONFIG_TRACER_MAX_TRACE +static void show_snapshot_main_help(struct seq_file *m) +{ + seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n"); + seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); + seq_printf(m, "# Takes a snapshot of the main buffer.\n"); + seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n"); + seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); + seq_printf(m, "# is not a '0' or '1')\n"); +} + +static void show_snapshot_percpu_help(struct seq_file *m) +{ + seq_printf(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); +#ifdef CONFIG_RING_BUFFER_ALLOW_SWAP + seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); + seq_printf(m, "# Takes a snapshot of the main buffer for this cpu.\n"); +#else + seq_printf(m, "# echo 1 > snapshot : Not supported with this kernel.\n"); + seq_printf(m, "# Must use main snapshot file to allocate.\n"); +#endif + seq_printf(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n"); + seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); + seq_printf(m, "# is not a '0' or '1')\n"); +} + +static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) +{ + if (iter->tr->allocated_snapshot) + seq_printf(m, "#\n# * Snapshot is allocated *\n#\n"); + else + seq_printf(m, "#\n# * Snapshot is freed *\n#\n"); + + seq_printf(m, "# Snapshot commands:\n"); + if (iter->cpu_file == RING_BUFFER_ALL_CPUS) + show_snapshot_main_help(m); + else + show_snapshot_percpu_help(m); +} +#else +/* Should never be called */ +static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } +#endif + static int s_show(struct seq_file *m, void *v) { struct trace_iterator *iter = v; + int ret; if (iter->ent == NULL) { if (iter->tr) { seq_printf(m, "# tracer: %s\n", iter->trace->name); seq_puts(m, "#\n"); + test_ftrace_alive(m); } - if (iter->trace && iter->trace->print_header) + if (iter->snapshot && trace_empty(iter)) + print_snapshot_help(m, iter); + else if (iter->trace && iter->trace->print_header) iter->trace->print_header(m); - else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { - /* print nothing if the buffers are empty */ - if (trace_empty(iter)) - return 0; - print_trace_header(m, iter); - if (!(trace_flags & TRACE_ITER_VERBOSE)) - print_lat_help_header(m); - } else { - if (!(trace_flags & TRACE_ITER_VERBOSE)) - print_func_help_header(m); - } + else + trace_default_header(m); + + } else if (iter->leftover) { + /* + * If we filled the seq_file buffer earlier, we + * want to just show it now. + */ + ret = trace_print_seq(m, &iter->seq); + + /* ret should this time be zero, but you never know */ + iter->leftover = ret; + } else { print_trace_line(iter); - trace_print_seq(m, &iter->seq); + ret = trace_print_seq(m, &iter->seq); + /* + * If we overflow the seq_file buffer, then it will + * ask us for this data again at start up. + * Use that instead. + * ret is 0 if seq_file write succeeded. + * -1 otherwise. + */ + iter->leftover = ret; } return 0; } -static struct seq_operations tracer_seq_ops = { +/* + * Should be used after trace_array_get(), trace_types_lock + * ensures that i_cdev was already initialized. + */ +static inline int tracing_get_cpu(struct inode *inode) +{ + if (inode->i_cdev) /* See trace_create_cpu_file() */ + return (long)inode->i_cdev - 1; + return RING_BUFFER_ALL_CPUS; +} + +static const struct seq_operations tracer_seq_ops = { .start = s_start, .next = s_next, .stop = s_stop, @@ -1891,21 +2993,24 @@ static struct seq_operations tracer_seq_ops = { }; static struct trace_iterator * -__tracing_open(struct inode *inode, struct file *file) +__tracing_open(struct inode *inode, struct file *file, bool snapshot) { - long cpu_file = (long) inode->i_private; - void *fail_ret = ERR_PTR(-ENOMEM); + struct trace_array *tr = inode->i_private; struct trace_iterator *iter; - struct seq_file *m; - int cpu, ret; + int cpu; if (tracing_disabled) return ERR_PTR(-ENODEV); - iter = kzalloc(sizeof(*iter), GFP_KERNEL); + iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); if (!iter) return ERR_PTR(-ENOMEM); + iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), + GFP_KERNEL); + if (!iter->buffer_iter) + goto release; + /* * We make a copy of the current tracer to avoid concurrent * changes on it while we are reading. @@ -1915,71 +3020,71 @@ __tracing_open(struct inode *inode, struct file *file) if (!iter->trace) goto fail; - if (current_trace) - *iter->trace = *current_trace; + *iter->trace = *tr->current_trace; - if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) + if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) goto fail; - cpumask_clear(iter->started); + iter->tr = tr; - if (current_trace && current_trace->print_max) - iter->tr = &max_tr; +#ifdef CONFIG_TRACER_MAX_TRACE + /* Currently only the top directory has a snapshot */ + if (tr->current_trace->print_max || snapshot) + iter->trace_buffer = &tr->max_buffer; else - iter->tr = &global_trace; +#endif + iter->trace_buffer = &tr->trace_buffer; + iter->snapshot = snapshot; iter->pos = -1; + iter->cpu_file = tracing_get_cpu(inode); mutex_init(&iter->mutex); - iter->cpu_file = cpu_file; /* Notify the tracer early; before we stop tracing. */ if (iter->trace && iter->trace->open) iter->trace->open(iter); /* Annotate start of buffers if we had overruns */ - if (ring_buffer_overruns(iter->tr->buffer)) + if (ring_buffer_overruns(iter->trace_buffer->buffer)) iter->iter_flags |= TRACE_FILE_ANNOTATE; - if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { - for_each_tracing_cpu(cpu) { + /* Output in nanoseconds only if we are using a clock in nanoseconds. */ + if (trace_clocks[tr->clock_id].in_ns) + iter->iter_flags |= TRACE_FILE_TIME_IN_NS; + /* stop the trace while dumping if we are not opening "snapshot" */ + if (!iter->snapshot) + tracing_stop_tr(tr); + + if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { + for_each_tracing_cpu(cpu) { iter->buffer_iter[cpu] = - ring_buffer_read_start(iter->tr->buffer, cpu); + ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); + } + ring_buffer_read_prepare_sync(); + for_each_tracing_cpu(cpu) { + ring_buffer_read_start(iter->buffer_iter[cpu]); + tracing_iter_reset(iter, cpu); } } else { cpu = iter->cpu_file; iter->buffer_iter[cpu] = - ring_buffer_read_start(iter->tr->buffer, cpu); + ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); + ring_buffer_read_prepare_sync(); + ring_buffer_read_start(iter->buffer_iter[cpu]); + tracing_iter_reset(iter, cpu); } - /* TODO stop tracer */ - ret = seq_open(file, &tracer_seq_ops); - if (ret < 0) { - fail_ret = ERR_PTR(ret); - goto fail_buffer; - } - - m = file->private_data; - m->private = iter; - - /* stop the trace while dumping */ - tracing_stop(); - mutex_unlock(&trace_types_lock); return iter; - fail_buffer: - for_each_tracing_cpu(cpu) { - if (iter->buffer_iter[cpu]) - ring_buffer_read_finish(iter->buffer_iter[cpu]); - } - free_cpumask_var(iter->started); fail: mutex_unlock(&trace_types_lock); kfree(iter->trace); - kfree(iter); - - return fail_ret; + kfree(iter->buffer_iter); +release: + seq_release_private(inode, file); + return ERR_PTR(-ENOMEM); } int tracing_open_generic(struct inode *inode, struct file *filp) @@ -1991,18 +3096,46 @@ int tracing_open_generic(struct inode *inode, struct file *filp) return 0; } +bool tracing_is_disabled(void) +{ + return (tracing_disabled) ? true: false; +} + +/* + * Open and update trace_array ref count. + * Must have the current trace_array passed to it. + */ +static int tracing_open_generic_tr(struct inode *inode, struct file *filp) +{ + struct trace_array *tr = inode->i_private; + + if (tracing_disabled) + return -ENODEV; + + if (trace_array_get(tr) < 0) + return -ENODEV; + + filp->private_data = inode->i_private; + + return 0; +} + static int tracing_release(struct inode *inode, struct file *file) { - struct seq_file *m = (struct seq_file *)file->private_data; + struct trace_array *tr = inode->i_private; + struct seq_file *m = file->private_data; struct trace_iterator *iter; int cpu; - if (!(file->f_mode & FMODE_READ)) + if (!(file->f_mode & FMODE_READ)) { + trace_array_put(tr); return 0; + } + /* Writes do not use seq_file */ iter = m->private; - mutex_lock(&trace_types_lock); + for_each_tracing_cpu(cpu) { if (iter->buffer_iter[cpu]) ring_buffer_read_finish(iter->buffer_iter[cpu]); @@ -2011,65 +3144,119 @@ static int tracing_release(struct inode *inode, struct file *file) if (iter->trace && iter->trace->close) iter->trace->close(iter); - /* reenable tracing if it was previously enabled */ - tracing_start(); + if (!iter->snapshot) + /* reenable tracing if it was previously enabled */ + tracing_start_tr(tr); + + __trace_array_put(tr); + mutex_unlock(&trace_types_lock); - seq_release(inode, file); mutex_destroy(&iter->mutex); free_cpumask_var(iter->started); kfree(iter->trace); - kfree(iter); + kfree(iter->buffer_iter); + seq_release_private(inode, file); + + return 0; +} + +static int tracing_release_generic_tr(struct inode *inode, struct file *file) +{ + struct trace_array *tr = inode->i_private; + + trace_array_put(tr); return 0; } +static int tracing_single_release_tr(struct inode *inode, struct file *file) +{ + struct trace_array *tr = inode->i_private; + + trace_array_put(tr); + + return single_release(inode, file); +} + static int tracing_open(struct inode *inode, struct file *file) { + struct trace_array *tr = inode->i_private; struct trace_iterator *iter; int ret = 0; + if (trace_array_get(tr) < 0) + return -ENODEV; + /* If this file was open for write, then erase contents */ - if ((file->f_mode & FMODE_WRITE) && - !(file->f_flags & O_APPEND)) { - long cpu = (long) inode->i_private; + if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { + int cpu = tracing_get_cpu(inode); - if (cpu == TRACE_PIPE_ALL_CPU) - tracing_reset_online_cpus(&global_trace); + if (cpu == RING_BUFFER_ALL_CPUS) + tracing_reset_online_cpus(&tr->trace_buffer); else - tracing_reset(&global_trace, cpu); + tracing_reset(&tr->trace_buffer, cpu); } if (file->f_mode & FMODE_READ) { - iter = __tracing_open(inode, file); + iter = __tracing_open(inode, file, false); if (IS_ERR(iter)) ret = PTR_ERR(iter); else if (trace_flags & TRACE_ITER_LATENCY_FMT) iter->iter_flags |= TRACE_FILE_LAT_FMT; } + + if (ret < 0) + trace_array_put(tr); + return ret; } +/* + * Some tracers are not suitable for instance buffers. + * A tracer is always available for the global array (toplevel) + * or if it explicitly states that it is. + */ +static bool +trace_ok_for_array(struct tracer *t, struct trace_array *tr) +{ + return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; +} + +/* Find the next tracer that this trace array may use */ +static struct tracer * +get_tracer_for_array(struct trace_array *tr, struct tracer *t) +{ + while (t && !trace_ok_for_array(t, tr)) + t = t->next; + + return t; +} + static void * t_next(struct seq_file *m, void *v, loff_t *pos) { + struct trace_array *tr = m->private; struct tracer *t = v; (*pos)++; if (t) - t = t->next; + t = get_tracer_for_array(tr, t->next); return t; } static void *t_start(struct seq_file *m, loff_t *pos) { + struct trace_array *tr = m->private; struct tracer *t; loff_t l = 0; mutex_lock(&trace_types_lock); - for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) - ; + + t = get_tracer_for_array(tr, trace_types); + for (; t && l < *pos; t = t_next(m, t, &l)) + ; return t; } @@ -2095,7 +3282,7 @@ static int t_show(struct seq_file *m, void *v) return 0; } -static struct seq_operations show_traces_seq_ops = { +static const struct seq_operations show_traces_seq_ops = { .start = t_start, .next = t_next, .stop = t_stop, @@ -2104,10 +3291,21 @@ static struct seq_operations show_traces_seq_ops = { static int show_traces_open(struct inode *inode, struct file *file) { + struct trace_array *tr = inode->i_private; + struct seq_file *m; + int ret; + if (tracing_disabled) return -ENODEV; - return seq_open(file, &show_traces_seq_ops); + ret = seq_open(file, &show_traces_seq_ops); + if (ret) + return ret; + + m = file->private_data; + m->private = tr; + + return 0; } static ssize_t @@ -2117,11 +3315,23 @@ tracing_write_stub(struct file *filp, const char __user *ubuf, return count; } +loff_t tracing_lseek(struct file *file, loff_t offset, int whence) +{ + int ret; + + if (file->f_mode & FMODE_READ) + ret = seq_lseek(file, offset, whence); + else + file->f_pos = ret = 0; + + return ret; +} + static const struct file_operations tracing_fops = { .open = tracing_open, .read = seq_read, .write = tracing_write_stub, - .llseek = seq_lseek, + .llseek = tracing_lseek, .release = tracing_release, }; @@ -2129,14 +3339,10 @@ static const struct file_operations show_traces_fops = { .open = show_traces_open, .read = seq_read, .release = seq_release, + .llseek = seq_lseek, }; /* - * Only trace on a CPU if the bitmask is set: - */ -static cpumask_var_t tracing_cpumask; - -/* * The tracer itself will not take this lock, but still we want * to provide a consistent cpumask to user-space: */ @@ -2152,11 +3358,12 @@ static ssize_t tracing_cpumask_read(struct file *filp, char __user *ubuf, size_t count, loff_t *ppos) { + struct trace_array *tr = file_inode(filp)->i_private; int len; mutex_lock(&tracing_cpumask_update_lock); - len = cpumask_scnprintf(mask_str, count, tracing_cpumask); + len = cpumask_scnprintf(mask_str, count, tr->tracing_cpumask); if (count - len < 2) { count = -EINVAL; goto out_err; @@ -2174,8 +3381,9 @@ static ssize_t tracing_cpumask_write(struct file *filp, const char __user *ubuf, size_t count, loff_t *ppos) { - int err, cpu; + struct trace_array *tr = file_inode(filp)->i_private; cpumask_var_t tracing_cpumask_new; + int err, cpu; if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) return -ENOMEM; @@ -2187,25 +3395,27 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf, mutex_lock(&tracing_cpumask_update_lock); local_irq_disable(); - __raw_spin_lock(&ftrace_max_lock); + arch_spin_lock(&tr->max_lock); for_each_tracing_cpu(cpu) { /* * Increase/decrease the disabled counter if we are * about to flip a bit in the cpumask: */ - if (cpumask_test_cpu(cpu, tracing_cpumask) && + if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && !cpumask_test_cpu(cpu, tracing_cpumask_new)) { - atomic_inc(&global_trace.data[cpu]->disabled); + atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); + ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); } - if (!cpumask_test_cpu(cpu, tracing_cpumask) && + if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && cpumask_test_cpu(cpu, tracing_cpumask_new)) { - atomic_dec(&global_trace.data[cpu]->disabled); + atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); + ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); } } - __raw_spin_unlock(&ftrace_max_lock); + arch_spin_unlock(&tr->max_lock); local_irq_enable(); - cpumask_copy(tracing_cpumask, tracing_cpumask_new); + cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); mutex_unlock(&tracing_cpumask_update_lock); free_cpumask_var(tracing_cpumask_new); @@ -2219,145 +3429,159 @@ err_unlock: } static const struct file_operations tracing_cpumask_fops = { - .open = tracing_open_generic, + .open = tracing_open_generic_tr, .read = tracing_cpumask_read, .write = tracing_cpumask_write, + .release = tracing_release_generic_tr, + .llseek = generic_file_llseek, }; -static ssize_t -tracing_trace_options_read(struct file *filp, char __user *ubuf, - size_t cnt, loff_t *ppos) +static int tracing_trace_options_show(struct seq_file *m, void *v) { struct tracer_opt *trace_opts; + struct trace_array *tr = m->private; u32 tracer_flags; - int len = 0; - char *buf; - int r = 0; int i; - - /* calculate max size */ - for (i = 0; trace_options[i]; i++) { - len += strlen(trace_options[i]); - len += 3; /* "no" and newline */ - } - mutex_lock(&trace_types_lock); - tracer_flags = current_trace->flags->val; - trace_opts = current_trace->flags->opts; - - /* - * Increase the size with names of options specific - * of the current tracer. - */ - for (i = 0; trace_opts[i].name; i++) { - len += strlen(trace_opts[i].name); - len += 3; /* "no" and newline */ - } - - /* +2 for \n and \0 */ - buf = kmalloc(len + 2, GFP_KERNEL); - if (!buf) { - mutex_unlock(&trace_types_lock); - return -ENOMEM; - } + tracer_flags = tr->current_trace->flags->val; + trace_opts = tr->current_trace->flags->opts; for (i = 0; trace_options[i]; i++) { if (trace_flags & (1 << i)) - r += sprintf(buf + r, "%s\n", trace_options[i]); + seq_printf(m, "%s\n", trace_options[i]); else - r += sprintf(buf + r, "no%s\n", trace_options[i]); + seq_printf(m, "no%s\n", trace_options[i]); } for (i = 0; trace_opts[i].name; i++) { if (tracer_flags & trace_opts[i].bit) - r += sprintf(buf + r, "%s\n", - trace_opts[i].name); + seq_printf(m, "%s\n", trace_opts[i].name); else - r += sprintf(buf + r, "no%s\n", - trace_opts[i].name); + seq_printf(m, "no%s\n", trace_opts[i].name); } mutex_unlock(&trace_types_lock); - WARN_ON(r >= len + 2); + return 0; +} - r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); +static int __set_tracer_option(struct trace_array *tr, + struct tracer_flags *tracer_flags, + struct tracer_opt *opts, int neg) +{ + struct tracer *trace = tr->current_trace; + int ret; - kfree(buf); - return r; + ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); + if (ret) + return ret; + + if (neg) + tracer_flags->val &= ~opts->bit; + else + tracer_flags->val |= opts->bit; + return 0; } /* Try to assign a tracer specific option */ -static int set_tracer_option(struct tracer *trace, char *cmp, int neg) +static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) { - struct tracer_flags *trace_flags = trace->flags; + struct tracer *trace = tr->current_trace; + struct tracer_flags *tracer_flags = trace->flags; struct tracer_opt *opts = NULL; - int ret = 0, i = 0; - int len; + int i; - for (i = 0; trace_flags->opts[i].name; i++) { - opts = &trace_flags->opts[i]; - len = strlen(opts->name); + for (i = 0; tracer_flags->opts[i].name; i++) { + opts = &tracer_flags->opts[i]; - if (strncmp(cmp, opts->name, len) == 0) { - ret = trace->set_flag(trace_flags->val, - opts->bit, !neg); - break; - } + if (strcmp(cmp, opts->name) == 0) + return __set_tracer_option(tr, trace->flags, opts, neg); } - /* Not found */ - if (!trace_flags->opts[i].name) - return -EINVAL; - /* Refused to handle */ - if (ret) - return ret; + return -EINVAL; +} - if (neg) - trace_flags->val &= ~opts->bit; - else - trace_flags->val |= opts->bit; +/* Some tracers require overwrite to stay enabled */ +int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) +{ + if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) + return -1; return 0; } -static void set_tracer_flags(unsigned int mask, int enabled) +int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) { /* do nothing if flag is already set */ if (!!(trace_flags & mask) == !!enabled) - return; + return 0; + + /* Give the tracer a chance to approve the change */ + if (tr->current_trace->flag_changed) + if (tr->current_trace->flag_changed(tr, mask, !!enabled)) + return -EINVAL; if (enabled) trace_flags |= mask; else trace_flags &= ~mask; - if (mask == TRACE_ITER_GLOBAL_CLK) { - u64 (*func)(void); + if (mask == TRACE_ITER_RECORD_CMD) + trace_event_enable_cmd_record(enabled); - if (enabled) - func = trace_clock_global; - else - func = trace_clock_local; + if (mask == TRACE_ITER_OVERWRITE) { + ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); +#ifdef CONFIG_TRACER_MAX_TRACE + ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); +#endif + } - mutex_lock(&trace_types_lock); - ring_buffer_set_clock(global_trace.buffer, func); + if (mask == TRACE_ITER_PRINTK) + trace_printk_start_stop_comm(enabled); - if (max_tr.buffer) - ring_buffer_set_clock(max_tr.buffer, func); - mutex_unlock(&trace_types_lock); + return 0; +} + +static int trace_set_options(struct trace_array *tr, char *option) +{ + char *cmp; + int neg = 0; + int ret = -ENODEV; + int i; + + cmp = strstrip(option); + + if (strncmp(cmp, "no", 2) == 0) { + neg = 1; + cmp += 2; + } + + mutex_lock(&trace_types_lock); + + for (i = 0; trace_options[i]; i++) { + if (strcmp(cmp, trace_options[i]) == 0) { + ret = set_tracer_flag(tr, 1 << i, !neg); + break; + } } + + /* If no option could be set, test the specific tracer options */ + if (!trace_options[i]) + ret = set_tracer_option(tr, cmp, neg); + + mutex_unlock(&trace_types_lock); + + return ret; } static ssize_t tracing_trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { + struct seq_file *m = filp->private_data; + struct trace_array *tr = m->private; char buf[64]; - char *cmp = buf; - int neg = 0; int ret; - int i; if (cnt >= sizeof(buf)) return -EINVAL; @@ -2367,56 +3591,167 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf, buf[cnt] = 0; - if (strncmp(buf, "no", 2) == 0) { - neg = 1; - cmp += 2; - } + ret = trace_set_options(tr, buf); + if (ret < 0) + return ret; - for (i = 0; trace_options[i]; i++) { - int len = strlen(trace_options[i]); + *ppos += cnt; - if (strncmp(cmp, trace_options[i], len) == 0) { - set_tracer_flags(1 << i, !neg); - break; - } - } + return cnt; +} - /* If no option could be set, test the specific tracer options */ - if (!trace_options[i]) { - mutex_lock(&trace_types_lock); - ret = set_tracer_option(current_trace, cmp, neg); - mutex_unlock(&trace_types_lock); - if (ret) - return ret; - } +static int tracing_trace_options_open(struct inode *inode, struct file *file) +{ + struct trace_array *tr = inode->i_private; + int ret; - filp->f_pos += cnt; + if (tracing_disabled) + return -ENODEV; - return cnt; + if (trace_array_get(tr) < 0) + return -ENODEV; + + ret = single_open(file, tracing_trace_options_show, inode->i_private); + if (ret < 0) + trace_array_put(tr); + + return ret; } static const struct file_operations tracing_iter_fops = { - .open = tracing_open_generic, - .read = tracing_trace_options_read, + .open = tracing_trace_options_open, + .read = seq_read, + .llseek = seq_lseek, + .release = tracing_single_release_tr, .write = tracing_trace_options_write, }; static const char readme_msg[] = "tracing mini-HOWTO:\n\n" - "# mount -t debugfs nodev /sys/kernel/debug\n\n" - "# cat /sys/kernel/debug/tracing/available_tracers\n" - "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" - "# cat /sys/kernel/debug/tracing/current_tracer\n" - "nop\n" - "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" - "# cat /sys/kernel/debug/tracing/current_tracer\n" - "sched_switch\n" - "# cat /sys/kernel/debug/tracing/trace_options\n" - "noprint-parent nosym-offset nosym-addr noverbose\n" - "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" - "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" - "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" - "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" + "# echo 0 > tracing_on : quick way to disable tracing\n" + "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" + " Important files:\n" + " trace\t\t\t- The static contents of the buffer\n" + "\t\t\t To clear the buffer write into this file: echo > trace\n" + " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" + " current_tracer\t- function and latency tracers\n" + " available_tracers\t- list of configured tracers for current_tracer\n" + " buffer_size_kb\t- view and modify size of per cpu buffer\n" + " buffer_total_size_kb - view total size of all cpu buffers\n\n" + " trace_clock\t\t-change the clock used to order events\n" + " local: Per cpu clock but may not be synced across CPUs\n" + " global: Synced across CPUs but slows tracing down.\n" + " counter: Not a clock, but just an increment\n" + " uptime: Jiffy counter from time of boot\n" + " perf: Same clock that perf events use\n" +#ifdef CONFIG_X86_64 + " x86-tsc: TSC cycle counter\n" +#endif + "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" + " tracing_cpumask\t- Limit which CPUs to trace\n" + " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" + "\t\t\t Remove sub-buffer with rmdir\n" + " trace_options\t\t- Set format or modify how tracing happens\n" + "\t\t\t Disable an option by adding a suffix 'no' to the\n" + "\t\t\t option name\n" + " saved_cmdlines_size\t- echo command number in here to store comm-pid list\n" +#ifdef CONFIG_DYNAMIC_FTRACE + "\n available_filter_functions - list of functions that can be filtered on\n" + " set_ftrace_filter\t- echo function name in here to only trace these\n" + "\t\t\t functions\n" + "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" + "\t modules: Can select a group via module\n" + "\t Format: :mod:<module-name>\n" + "\t example: echo :mod:ext3 > set_ftrace_filter\n" + "\t triggers: a command to perform when function is hit\n" + "\t Format: <function>:<trigger>[:count]\n" + "\t trigger: traceon, traceoff\n" + "\t\t enable_event:<system>:<event>\n" + "\t\t disable_event:<system>:<event>\n" +#ifdef CONFIG_STACKTRACE + "\t\t stacktrace\n" +#endif +#ifdef CONFIG_TRACER_SNAPSHOT + "\t\t snapshot\n" +#endif + "\t\t dump\n" + "\t\t cpudump\n" + "\t example: echo do_fault:traceoff > set_ftrace_filter\n" + "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" + "\t The first one will disable tracing every time do_fault is hit\n" + "\t The second will disable tracing at most 3 times when do_trap is hit\n" + "\t The first time do trap is hit and it disables tracing, the\n" + "\t counter will decrement to 2. If tracing is already disabled,\n" + "\t the counter will not decrement. It only decrements when the\n" + "\t trigger did work\n" + "\t To remove trigger without count:\n" + "\t echo '!<function>:<trigger> > set_ftrace_filter\n" + "\t To remove trigger with a count:\n" + "\t echo '!<function>:<trigger>:0 > set_ftrace_filter\n" + " set_ftrace_notrace\t- echo function name in here to never trace.\n" + "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" + "\t modules: Can select a group via module command :mod:\n" + "\t Does not accept triggers\n" +#endif /* CONFIG_DYNAMIC_FTRACE */ +#ifdef CONFIG_FUNCTION_TRACER + " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" + "\t\t (function)\n" +#endif +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" + " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" +#endif +#ifdef CONFIG_TRACER_SNAPSHOT + "\n snapshot\t\t- Like 'trace' but shows the content of the static\n" + "\t\t\t snapshot buffer. Read the contents for more\n" + "\t\t\t information\n" +#endif +#ifdef CONFIG_STACK_TRACER + " stack_trace\t\t- Shows the max stack trace when active\n" + " stack_max_size\t- Shows current max stack size that was traced\n" + "\t\t\t Write into this file to reset the max size (trigger a\n" + "\t\t\t new trace)\n" +#ifdef CONFIG_DYNAMIC_FTRACE + " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n" + "\t\t\t traces\n" +#endif +#endif /* CONFIG_STACK_TRACER */ + " events/\t\t- Directory containing all trace event subsystems:\n" + " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" + " events/<system>/\t- Directory containing all trace events for <system>:\n" + " enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n" + "\t\t\t events\n" + " filter\t\t- If set, only events passing filter are traced\n" + " events/<system>/<event>/\t- Directory containing control files for\n" + "\t\t\t <event>:\n" + " enable\t\t- Write 0/1 to enable/disable tracing of <event>\n" + " filter\t\t- If set, only events passing filter are traced\n" + " trigger\t\t- If set, a command to perform when event is hit\n" + "\t Format: <trigger>[:count][if <filter>]\n" + "\t trigger: traceon, traceoff\n" + "\t enable_event:<system>:<event>\n" + "\t disable_event:<system>:<event>\n" +#ifdef CONFIG_STACKTRACE + "\t\t stacktrace\n" +#endif +#ifdef CONFIG_TRACER_SNAPSHOT + "\t\t snapshot\n" +#endif + "\t example: echo traceoff > events/block/block_unplug/trigger\n" + "\t echo traceoff:3 > events/block/block_unplug/trigger\n" + "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" + "\t events/block/block_unplug/trigger\n" + "\t The first disables tracing every time block_unplug is hit.\n" + "\t The second disables tracing the first 3 times block_unplug is hit.\n" + "\t The third enables the kmalloc event the first 3 times block_unplug\n" + "\t is hit and has value of greater than 1 for the 'nr_rq' event field.\n" + "\t Like function triggers, the counter is only decremented if it\n" + "\t enabled or disabled tracing.\n" + "\t To remove a trigger without a count:\n" + "\t echo '!<trigger> > <system>/<event>/trigger\n" + "\t To remove a trigger with a count:\n" + "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" + "\t Filters can be ignored when removing a trigger.\n" ; static ssize_t @@ -2430,125 +3765,168 @@ tracing_readme_read(struct file *filp, char __user *ubuf, static const struct file_operations tracing_readme_fops = { .open = tracing_open_generic, .read = tracing_readme_read, + .llseek = generic_file_llseek, }; -static ssize_t -tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, - size_t cnt, loff_t *ppos) +static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos) { - char *buf_comm; - char *file_buf; - char *buf; - int len = 0; - int pid; - int i; + unsigned int *ptr = v; - file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); - if (!file_buf) - return -ENOMEM; + if (*pos || m->count) + ptr++; - buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); - if (!buf_comm) { - kfree(file_buf); - return -ENOMEM; + (*pos)++; + + for (; ptr < &savedcmd->map_cmdline_to_pid[savedcmd->cmdline_num]; + ptr++) { + if (*ptr == -1 || *ptr == NO_CMDLINE_MAP) + continue; + + return ptr; } - buf = file_buf; + return NULL; +} - for (i = 0; i < SAVED_CMDLINES; i++) { - int r; +static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos) +{ + void *v; + loff_t l = 0; - pid = map_cmdline_to_pid[i]; - if (pid == -1 || pid == NO_CMDLINE_MAP) - continue; + preempt_disable(); + arch_spin_lock(&trace_cmdline_lock); - trace_find_cmdline(pid, buf_comm); - r = sprintf(buf, "%d %s\n", pid, buf_comm); - buf += r; - len += r; + v = &savedcmd->map_cmdline_to_pid[0]; + while (l <= *pos) { + v = saved_cmdlines_next(m, v, &l); + if (!v) + return NULL; } - len = simple_read_from_buffer(ubuf, cnt, ppos, - file_buf, len); + return v; +} + +static void saved_cmdlines_stop(struct seq_file *m, void *v) +{ + arch_spin_unlock(&trace_cmdline_lock); + preempt_enable(); +} - kfree(file_buf); - kfree(buf_comm); +static int saved_cmdlines_show(struct seq_file *m, void *v) +{ + char buf[TASK_COMM_LEN]; + unsigned int *pid = v; - return len; + __trace_find_cmdline(*pid, buf); + seq_printf(m, "%d %s\n", *pid, buf); + return 0; +} + +static const struct seq_operations tracing_saved_cmdlines_seq_ops = { + .start = saved_cmdlines_start, + .next = saved_cmdlines_next, + .stop = saved_cmdlines_stop, + .show = saved_cmdlines_show, +}; + +static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp) +{ + if (tracing_disabled) + return -ENODEV; + + return seq_open(filp, &tracing_saved_cmdlines_seq_ops); } static const struct file_operations tracing_saved_cmdlines_fops = { - .open = tracing_open_generic, - .read = tracing_saved_cmdlines_read, + .open = tracing_saved_cmdlines_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, }; static ssize_t -tracing_ctrl_read(struct file *filp, char __user *ubuf, - size_t cnt, loff_t *ppos) +tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) { char buf[64]; int r; - r = sprintf(buf, "%u\n", tracer_enabled); + arch_spin_lock(&trace_cmdline_lock); + r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num); + arch_spin_unlock(&trace_cmdline_lock); + return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); } +static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s) +{ + kfree(s->saved_cmdlines); + kfree(s->map_cmdline_to_pid); + kfree(s); +} + +static int tracing_resize_saved_cmdlines(unsigned int val) +{ + struct saved_cmdlines_buffer *s, *savedcmd_temp; + + s = kmalloc(sizeof(*s), GFP_KERNEL); + if (!s) + return -ENOMEM; + + if (allocate_cmdlines_buffer(val, s) < 0) { + kfree(s); + return -ENOMEM; + } + + arch_spin_lock(&trace_cmdline_lock); + savedcmd_temp = savedcmd; + savedcmd = s; + arch_spin_unlock(&trace_cmdline_lock); + free_saved_cmdlines_buffer(savedcmd_temp); + + return 0; +} + static ssize_t -tracing_ctrl_write(struct file *filp, const char __user *ubuf, - size_t cnt, loff_t *ppos) +tracing_saved_cmdlines_size_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos) { - struct trace_array *tr = filp->private_data; - char buf[64]; unsigned long val; int ret; - if (cnt >= sizeof(buf)) - return -EINVAL; - - if (copy_from_user(&buf, ubuf, cnt)) - return -EFAULT; + ret = kstrtoul_from_user(ubuf, cnt, 10, &val); + if (ret) + return ret; - buf[cnt] = 0; + /* must have at least 1 entry or less than PID_MAX_DEFAULT */ + if (!val || val > PID_MAX_DEFAULT) + return -EINVAL; - ret = strict_strtoul(buf, 10, &val); + ret = tracing_resize_saved_cmdlines((unsigned int)val); if (ret < 0) return ret; - val = !!val; - - mutex_lock(&trace_types_lock); - if (tracer_enabled ^ val) { - if (val) { - tracer_enabled = 1; - if (current_trace->start) - current_trace->start(tr); - tracing_start(); - } else { - tracer_enabled = 0; - tracing_stop(); - if (current_trace->stop) - current_trace->stop(tr); - } - } - mutex_unlock(&trace_types_lock); - - filp->f_pos += cnt; + *ppos += cnt; return cnt; } +static const struct file_operations tracing_saved_cmdlines_size_fops = { + .open = tracing_open_generic, + .read = tracing_saved_cmdlines_size_read, + .write = tracing_saved_cmdlines_size_write, +}; + static ssize_t tracing_set_trace_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { - char buf[max_tracer_type_len+2]; + struct trace_array *tr = filp->private_data; + char buf[MAX_TRACER_SIZE+2]; int r; mutex_lock(&trace_types_lock); - if (current_trace) - r = sprintf(buf, "%s\n", current_trace->name); - else - r = sprintf(buf, "\n"); + r = sprintf(buf, "%s\n", tr->current_trace->name); mutex_unlock(&trace_types_lock); return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); @@ -2556,11 +3934,48 @@ tracing_set_trace_read(struct file *filp, char __user *ubuf, int tracer_init(struct tracer *t, struct trace_array *tr) { - tracing_reset_online_cpus(tr); + tracing_reset_online_cpus(&tr->trace_buffer); return t->init(tr); } -static int tracing_resize_ring_buffer(unsigned long size) +static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) +{ + int cpu; + + for_each_tracing_cpu(cpu) + per_cpu_ptr(buf->data, cpu)->entries = val; +} + +#ifdef CONFIG_TRACER_MAX_TRACE +/* resize @tr's buffer to the size of @size_tr's entries */ +static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, + struct trace_buffer *size_buf, int cpu_id) +{ + int cpu, ret = 0; + + if (cpu_id == RING_BUFFER_ALL_CPUS) { + for_each_tracing_cpu(cpu) { + ret = ring_buffer_resize(trace_buf->buffer, + per_cpu_ptr(size_buf->data, cpu)->entries, cpu); + if (ret < 0) + break; + per_cpu_ptr(trace_buf->data, cpu)->entries = + per_cpu_ptr(size_buf->data, cpu)->entries; + } + } else { + ret = ring_buffer_resize(trace_buf->buffer, + per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); + if (ret == 0) + per_cpu_ptr(trace_buf->data, cpu_id)->entries = + per_cpu_ptr(size_buf->data, cpu_id)->entries; + } + + return ret; +} +#endif /* CONFIG_TRACER_MAX_TRACE */ + +static int __tracing_resize_ring_buffer(struct trace_array *tr, + unsigned long size, int cpu) { int ret; @@ -2569,18 +3984,25 @@ static int tracing_resize_ring_buffer(unsigned long size) * we use the size that was given, and we can forget about * expanding it later. */ - ring_buffer_expanded = 1; + ring_buffer_expanded = true; + + /* May be called before buffers are initialized */ + if (!tr->trace_buffer.buffer) + return 0; - ret = ring_buffer_resize(global_trace.buffer, size); + ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); if (ret < 0) return ret; - ret = ring_buffer_resize(max_tr.buffer, size); - if (ret < 0) { - int r; +#ifdef CONFIG_TRACER_MAX_TRACE + if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || + !tr->current_trace->use_max_tr) + goto out; - r = ring_buffer_resize(global_trace.buffer, - global_trace.entries); + ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); + if (ret < 0) { + int r = resize_buffer_duplicate_size(&tr->trace_buffer, + &tr->trace_buffer, cpu); if (r < 0) { /* * AARGH! We are left with different @@ -2602,11 +4024,48 @@ static int tracing_resize_ring_buffer(unsigned long size) return ret; } - global_trace.entries = size; + if (cpu == RING_BUFFER_ALL_CPUS) + set_buffer_entries(&tr->max_buffer, size); + else + per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; + + out: +#endif /* CONFIG_TRACER_MAX_TRACE */ + + if (cpu == RING_BUFFER_ALL_CPUS) + set_buffer_entries(&tr->trace_buffer, size); + else + per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; + + return ret; +} + +static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, + unsigned long size, int cpu_id) +{ + int ret = size; + + mutex_lock(&trace_types_lock); + + if (cpu_id != RING_BUFFER_ALL_CPUS) { + /* make sure, this cpu is enabled in the mask */ + if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { + ret = -EINVAL; + goto out; + } + } + + ret = __tracing_resize_ring_buffer(tr, size, cpu_id); + if (ret < 0) + ret = -ENOMEM; + +out: + mutex_unlock(&trace_types_lock); return ret; } + /** * tracing_update_buffers - used by tracing facility to expand ring buffers * @@ -2623,7 +4082,8 @@ int tracing_update_buffers(void) mutex_lock(&trace_types_lock); if (!ring_buffer_expanded) - ret = tracing_resize_ring_buffer(trace_buf_size); + ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, + RING_BUFFER_ALL_CPUS); mutex_unlock(&trace_types_lock); return ret; @@ -2632,22 +4092,42 @@ int tracing_update_buffers(void) struct trace_option_dentry; static struct trace_option_dentry * -create_trace_option_files(struct tracer *tracer); +create_trace_option_files(struct trace_array *tr, struct tracer *tracer); static void destroy_trace_option_files(struct trace_option_dentry *topts); -static int tracing_set_tracer(const char *buf) +/* + * Used to clear out the tracer before deletion of an instance. + * Must have trace_types_lock held. + */ +static void tracing_set_nop(struct trace_array *tr) +{ + if (tr->current_trace == &nop_trace) + return; + + tr->current_trace->enabled--; + + if (tr->current_trace->reset) + tr->current_trace->reset(tr); + + tr->current_trace = &nop_trace; +} + +static int tracing_set_tracer(struct trace_array *tr, const char *buf) { static struct trace_option_dentry *topts; - struct trace_array *tr = &global_trace; struct tracer *t; +#ifdef CONFIG_TRACER_MAX_TRACE + bool had_max_tr; +#endif int ret = 0; mutex_lock(&trace_types_lock); if (!ring_buffer_expanded) { - ret = tracing_resize_ring_buffer(trace_buf_size); + ret = __tracing_resize_ring_buffer(tr, trace_buf_size, + RING_BUFFER_ALL_CPUS); if (ret < 0) goto out; ret = 0; @@ -2661,18 +4141,53 @@ static int tracing_set_tracer(const char *buf) ret = -EINVAL; goto out; } - if (t == current_trace) + if (t == tr->current_trace) goto out; + /* Some tracers are only allowed for the top level buffer */ + if (!trace_ok_for_array(t, tr)) { + ret = -EINVAL; + goto out; + } + trace_branch_disable(); - if (current_trace && current_trace->reset) - current_trace->reset(tr); - destroy_trace_option_files(topts); + tr->current_trace->enabled--; + + if (tr->current_trace->reset) + tr->current_trace->reset(tr); - current_trace = t; + /* Current trace needs to be nop_trace before synchronize_sched */ + tr->current_trace = &nop_trace; - topts = create_trace_option_files(current_trace); +#ifdef CONFIG_TRACER_MAX_TRACE + had_max_tr = tr->allocated_snapshot; + + if (had_max_tr && !t->use_max_tr) { + /* + * We need to make sure that the update_max_tr sees that + * current_trace changed to nop_trace to keep it from + * swapping the buffers after we resize it. + * The update_max_tr is called from interrupts disabled + * so a synchronized_sched() is sufficient. + */ + synchronize_sched(); + free_snapshot(tr); + } +#endif + /* Currently, only the top instance has options */ + if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { + destroy_trace_option_files(topts); + topts = create_trace_option_files(tr, t); + } + +#ifdef CONFIG_TRACER_MAX_TRACE + if (t->use_max_tr && !had_max_tr) { + ret = alloc_snapshot(tr); + if (ret < 0) + goto out; + } +#endif if (t->init) { ret = tracer_init(t, tr); @@ -2680,6 +4195,8 @@ static int tracing_set_tracer(const char *buf) goto out; } + tr->current_trace = t; + tr->current_trace->enabled++; trace_branch_enable(tr); out: mutex_unlock(&trace_types_lock); @@ -2691,15 +4208,16 @@ static ssize_t tracing_set_trace_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { - char buf[max_tracer_type_len+1]; + struct trace_array *tr = filp->private_data; + char buf[MAX_TRACER_SIZE+1]; int i; size_t ret; int err; ret = cnt; - if (cnt > max_tracer_type_len) - cnt = max_tracer_type_len; + if (cnt > MAX_TRACER_SIZE) + cnt = MAX_TRACER_SIZE; if (copy_from_user(&buf, ubuf, cnt)) return -EFAULT; @@ -2710,11 +4228,11 @@ tracing_set_trace_write(struct file *filp, const char __user *ubuf, for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) buf[i] = 0; - err = tracing_set_tracer(buf); + err = tracing_set_tracer(tr, buf); if (err) return err; - filp->f_pos += ret; + *ppos += ret; return ret; } @@ -2739,20 +4257,11 @@ tracing_max_lat_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { unsigned long *ptr = filp->private_data; - char buf[64]; unsigned long val; int ret; - if (cnt >= sizeof(buf)) - return -EINVAL; - - if (copy_from_user(&buf, ubuf, cnt)) - return -EFAULT; - - buf[cnt] = 0; - - ret = strict_strtoul(buf, 10, &val); - if (ret < 0) + ret = kstrtoul_from_user(ubuf, cnt, 10, &val); + if (ret) return ret; *ptr = val * 1000; @@ -2762,35 +4271,23 @@ tracing_max_lat_write(struct file *filp, const char __user *ubuf, static int tracing_open_pipe(struct inode *inode, struct file *filp) { - long cpu_file = (long) inode->i_private; + struct trace_array *tr = inode->i_private; struct trace_iterator *iter; int ret = 0; if (tracing_disabled) return -ENODEV; - mutex_lock(&trace_types_lock); + if (trace_array_get(tr) < 0) + return -ENODEV; - /* We only allow one reader per cpu */ - if (cpu_file == TRACE_PIPE_ALL_CPU) { - if (!cpumask_empty(tracing_reader_cpumask)) { - ret = -EBUSY; - goto out; - } - cpumask_setall(tracing_reader_cpumask); - } else { - if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask)) - cpumask_set_cpu(cpu_file, tracing_reader_cpumask); - else { - ret = -EBUSY; - goto out; - } - } + mutex_lock(&trace_types_lock); /* create a buffer to store the information to pass to userspace */ iter = kzalloc(sizeof(*iter), GFP_KERNEL); if (!iter) { ret = -ENOMEM; + __trace_array_put(tr); goto out; } @@ -2803,8 +4300,7 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) ret = -ENOMEM; goto fail; } - if (current_trace) - *iter->trace = *current_trace; + *iter->trace = *tr->current_trace; if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { ret = -ENOMEM; @@ -2817,14 +4313,20 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) if (trace_flags & TRACE_ITER_LATENCY_FMT) iter->iter_flags |= TRACE_FILE_LAT_FMT; - iter->cpu_file = cpu_file; - iter->tr = &global_trace; + /* Output in nanoseconds only if we are using a clock in nanoseconds. */ + if (trace_clocks[tr->clock_id].in_ns) + iter->iter_flags |= TRACE_FILE_TIME_IN_NS; + + iter->tr = tr; + iter->trace_buffer = &tr->trace_buffer; + iter->cpu_file = tracing_get_cpu(inode); mutex_init(&iter->mutex); filp->private_data = iter; if (iter->trace->pipe_open) iter->trace->pipe_open(iter); + nonseekable_open(inode, filp); out: mutex_unlock(&trace_types_lock); return ret; @@ -2832,6 +4334,7 @@ out: fail: kfree(iter->trace); kfree(iter); + __trace_array_put(tr); mutex_unlock(&trace_types_lock); return ret; } @@ -2839,13 +4342,12 @@ fail: static int tracing_release_pipe(struct inode *inode, struct file *file) { struct trace_iterator *iter = file->private_data; + struct trace_array *tr = inode->i_private; mutex_lock(&trace_types_lock); - if (iter->cpu_file == TRACE_PIPE_ALL_CPU) - cpumask_clear(tracing_reader_cpumask); - else - cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); + if (iter->trace->pipe_close) + iter->trace->pipe_close(iter); mutex_unlock(&trace_types_lock); @@ -2854,66 +4356,41 @@ static int tracing_release_pipe(struct inode *inode, struct file *file) kfree(iter->trace); kfree(iter); + trace_array_put(tr); + return 0; } static unsigned int -tracing_poll_pipe(struct file *filp, poll_table *poll_table) +trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) { - struct trace_iterator *iter = filp->private_data; + /* Iterators are static, they should be filled or empty */ + if (trace_buffer_iter(iter, iter->cpu_file)) + return POLLIN | POLLRDNORM; - if (trace_flags & TRACE_ITER_BLOCK) { + if (trace_flags & TRACE_ITER_BLOCK) /* * Always select as readable when in blocking mode */ return POLLIN | POLLRDNORM; - } else { - if (!trace_empty(iter)) - return POLLIN | POLLRDNORM; - poll_wait(filp, &trace_wait, poll_table); - if (!trace_empty(iter)) - return POLLIN | POLLRDNORM; - - return 0; - } + else + return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, + filp, poll_table); } - -void default_wait_pipe(struct trace_iterator *iter) +static unsigned int +tracing_poll_pipe(struct file *filp, poll_table *poll_table) { - DEFINE_WAIT(wait); - - prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); - - if (trace_empty(iter)) - schedule(); - - finish_wait(&trace_wait, &wait); -} + struct trace_iterator *iter = filp->private_data; -/* - * This is a make-shift waitqueue. - * A tracer might use this callback on some rare cases: - * - * 1) the current tracer might hold the runqueue lock when it wakes up - * a reader, hence a deadlock (sched, function, and function graph tracers) - * 2) the function tracers, trace all functions, we don't want - * the overhead of calling wake_up and friends - * (and tracing them too) - * - * Anyway, this is really very primitive wakeup. - */ -void poll_wait_pipe(struct trace_iterator *iter) -{ - set_current_state(TASK_INTERRUPTIBLE); - /* sleep for 100 msecs, and try again. */ - schedule_timeout(HZ / 10); + return trace_poll(iter, filp, poll_table); } /* Must be called with trace_types_lock mutex held. */ static int tracing_wait_pipe(struct file *filp) { struct trace_iterator *iter = filp->private_data; + int ret; while (trace_empty(iter)) { @@ -2921,15 +4398,6 @@ static int tracing_wait_pipe(struct file *filp) return -EAGAIN; } - mutex_unlock(&iter->mutex); - - iter->trace->wait_pipe(iter); - - mutex_lock(&iter->mutex); - - if (signal_pending(current)) - return -EINTR; - /* * We block until we read something and tracing is disabled. * We still block if tracing is disabled, but we have never @@ -2939,8 +4407,20 @@ static int tracing_wait_pipe(struct file *filp) * * iter->pos will be 0 if we haven't read anything. */ - if (!tracer_enabled && iter->pos) + if (!tracing_is_on() && iter->pos) break; + + mutex_unlock(&iter->mutex); + + ret = wait_on_pipe(iter); + + mutex_lock(&iter->mutex); + + if (ret) + return ret; + + if (signal_pending(current)) + return -EINTR; } return 1; @@ -2954,7 +4434,7 @@ tracing_read_pipe(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { struct trace_iterator *iter = filp->private_data; - static struct tracer *old_tracer; + struct trace_array *tr = iter->tr; ssize_t sret; /* return any leftover data */ @@ -2966,10 +4446,8 @@ tracing_read_pipe(struct file *filp, char __user *ubuf, /* copy the tracer to avoid using a global lock all around */ mutex_lock(&trace_types_lock); - if (unlikely(old_tracer != current_trace && current_trace)) { - old_tracer = current_trace; - *iter->trace = *current_trace; - } + if (unlikely(iter->trace->name != tr->current_trace->name)) + *iter->trace = *tr->current_trace; mutex_unlock(&trace_types_lock); /* @@ -3002,10 +4480,12 @@ waitagain: memset(&iter->seq, 0, sizeof(struct trace_iterator) - offsetof(struct trace_iterator, seq)); + cpumask_clear(iter->started); iter->pos = -1; trace_event_read_lock(); - while (find_next_entry_inc(iter) != NULL) { + trace_access_lock(iter->cpu_file); + while (trace_find_next_entry_inc(iter) != NULL) { enum print_line_t ret; int len = iter->seq.len; @@ -3020,7 +4500,16 @@ waitagain: if (iter->seq.len >= cnt) break; + + /* + * Setting the full flag means we reached the trace_seq buffer + * size and we should leave by partial output condition above. + * One of the trace_seq_* functions is not used properly. + */ + WARN_ONCE(iter->seq.full, "full flag set for trace type %d", + iter->ent->type); } + trace_access_unlock(iter->cpu_file); trace_event_read_unlock(); /* Now copy what we have to the user */ @@ -3029,7 +4518,7 @@ waitagain: trace_seq_init(&iter->seq); /* - * If there was nothing to send to user, inspite of consuming trace + * If there was nothing to send to user, in spite of consuming trace * entries, go back to wait for more entries. */ if (sret == -EBUSY) @@ -3041,24 +4530,16 @@ out: return sret; } -static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, - struct pipe_buffer *buf) -{ - __free_page(buf->page); -} - static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, unsigned int idx) { __free_page(spd->pages[idx]); } -static struct pipe_buf_operations tracing_pipe_buf_ops = { +static const struct pipe_buf_operations tracing_pipe_buf_ops = { .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, - .release = tracing_pipe_buf_release, + .release = generic_pipe_buf_release, .steal = generic_pipe_buf_steal, .get = generic_pipe_buf_get, }; @@ -3084,9 +4565,10 @@ tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) break; } - trace_consume(iter); + if (ret != TRACE_TYPE_NO_CONSUME) + trace_consume(iter); rem -= count; - if (!find_next_entry_inc(iter)) { + if (!trace_find_next_entry_inc(iter)) { rem = 0; iter->ent = NULL; break; @@ -3102,28 +4584,30 @@ static ssize_t tracing_splice_read_pipe(struct file *filp, size_t len, unsigned int flags) { - struct page *pages[PIPE_BUFFERS]; - struct partial_page partial[PIPE_BUFFERS]; + struct page *pages_def[PIPE_DEF_BUFFERS]; + struct partial_page partial_def[PIPE_DEF_BUFFERS]; struct trace_iterator *iter = filp->private_data; struct splice_pipe_desc spd = { - .pages = pages, - .partial = partial, + .pages = pages_def, + .partial = partial_def, .nr_pages = 0, /* This gets updated below. */ + .nr_pages_max = PIPE_DEF_BUFFERS, .flags = flags, .ops = &tracing_pipe_buf_ops, .spd_release = tracing_spd_release_pipe, }; - static struct tracer *old_tracer; + struct trace_array *tr = iter->tr; ssize_t ret; size_t rem; unsigned int i; + if (splice_grow_spd(pipe, &spd)) + return -ENOMEM; + /* copy the tracer to avoid using a global lock all around */ mutex_lock(&trace_types_lock); - if (unlikely(old_tracer != current_trace && current_trace)) { - old_tracer = current_trace; - *iter->trace = *current_trace; - } + if (unlikely(iter->trace->name != tr->current_trace->name)) + *iter->trace = *tr->current_trace; mutex_unlock(&trace_types_lock); mutex_lock(&iter->mutex); @@ -3139,196 +4623,565 @@ static ssize_t tracing_splice_read_pipe(struct file *filp, if (ret <= 0) goto out_err; - if (!iter->ent && !find_next_entry_inc(iter)) { + if (!iter->ent && !trace_find_next_entry_inc(iter)) { ret = -EFAULT; goto out_err; } trace_event_read_lock(); + trace_access_lock(iter->cpu_file); /* Fill as many pages as possible. */ - for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { - pages[i] = alloc_page(GFP_KERNEL); - if (!pages[i]) + for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) { + spd.pages[i] = alloc_page(GFP_KERNEL); + if (!spd.pages[i]) break; rem = tracing_fill_pipe_page(rem, iter); /* Copy the data into the page, so we can start over. */ ret = trace_seq_to_buffer(&iter->seq, - page_address(pages[i]), + page_address(spd.pages[i]), iter->seq.len); if (ret < 0) { - __free_page(pages[i]); + __free_page(spd.pages[i]); break; } - partial[i].offset = 0; - partial[i].len = iter->seq.len; + spd.partial[i].offset = 0; + spd.partial[i].len = iter->seq.len; trace_seq_init(&iter->seq); } + trace_access_unlock(iter->cpu_file); trace_event_read_unlock(); mutex_unlock(&iter->mutex); spd.nr_pages = i; - return splice_to_pipe(pipe, &spd); + ret = splice_to_pipe(pipe, &spd); +out: + splice_shrink_spd(&spd); + return ret; out_err: mutex_unlock(&iter->mutex); - - return ret; + goto out; } static ssize_t tracing_entries_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { - struct trace_array *tr = filp->private_data; - char buf[96]; - int r; + struct inode *inode = file_inode(filp); + struct trace_array *tr = inode->i_private; + int cpu = tracing_get_cpu(inode); + char buf[64]; + int r = 0; + ssize_t ret; mutex_lock(&trace_types_lock); - if (!ring_buffer_expanded) - r = sprintf(buf, "%lu (expanded: %lu)\n", - tr->entries >> 10, - trace_buf_size >> 10); - else - r = sprintf(buf, "%lu\n", tr->entries >> 10); + + if (cpu == RING_BUFFER_ALL_CPUS) { + int cpu, buf_size_same; + unsigned long size; + + size = 0; + buf_size_same = 1; + /* check if all cpu sizes are same */ + for_each_tracing_cpu(cpu) { + /* fill in the size from first enabled cpu */ + if (size == 0) + size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; + if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { + buf_size_same = 0; + break; + } + } + + if (buf_size_same) { + if (!ring_buffer_expanded) + r = sprintf(buf, "%lu (expanded: %lu)\n", + size >> 10, + trace_buf_size >> 10); + else + r = sprintf(buf, "%lu\n", size >> 10); + } else + r = sprintf(buf, "X\n"); + } else + r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10); + mutex_unlock(&trace_types_lock); - return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); + ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); + return ret; } static ssize_t tracing_entries_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { + struct inode *inode = file_inode(filp); + struct trace_array *tr = inode->i_private; unsigned long val; - char buf[64]; - int ret, cpu; - - if (cnt >= sizeof(buf)) - return -EINVAL; - - if (copy_from_user(&buf, ubuf, cnt)) - return -EFAULT; - - buf[cnt] = 0; + int ret; - ret = strict_strtoul(buf, 10, &val); - if (ret < 0) + ret = kstrtoul_from_user(ubuf, cnt, 10, &val); + if (ret) return ret; /* must have at least 1 entry */ if (!val) return -EINVAL; - mutex_lock(&trace_types_lock); - - tracing_stop(); - - /* disable all cpu buffers */ - for_each_tracing_cpu(cpu) { - if (global_trace.data[cpu]) - atomic_inc(&global_trace.data[cpu]->disabled); - if (max_tr.data[cpu]) - atomic_inc(&max_tr.data[cpu]->disabled); - } - /* value is in KB */ val <<= 10; + ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); + if (ret < 0) + return ret; - if (val != global_trace.entries) { - ret = tracing_resize_ring_buffer(val); - if (ret < 0) { - cnt = ret; - goto out; - } - } + *ppos += cnt; - filp->f_pos += cnt; + return cnt; +} - /* If check pages failed, return ENOMEM */ - if (tracing_disabled) - cnt = -ENOMEM; - out: +static ssize_t +tracing_total_entries_read(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + struct trace_array *tr = filp->private_data; + char buf[64]; + int r, cpu; + unsigned long size = 0, expanded_size = 0; + + mutex_lock(&trace_types_lock); for_each_tracing_cpu(cpu) { - if (global_trace.data[cpu]) - atomic_dec(&global_trace.data[cpu]->disabled); - if (max_tr.data[cpu]) - atomic_dec(&max_tr.data[cpu]->disabled); + size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; + if (!ring_buffer_expanded) + expanded_size += trace_buf_size >> 10; } - - tracing_start(); - max_tr.entries = global_trace.entries; + if (ring_buffer_expanded) + r = sprintf(buf, "%lu\n", size); + else + r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); mutex_unlock(&trace_types_lock); + return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); +} + +static ssize_t +tracing_free_buffer_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + /* + * There is no need to read what the user has written, this function + * is just to make sure that there is no error when "echo" is used + */ + + *ppos += cnt; + return cnt; } -static int mark_printk(const char *fmt, ...) +static int +tracing_free_buffer_release(struct inode *inode, struct file *filp) { - int ret; - va_list args; - va_start(args, fmt); - ret = trace_vprintk(0, fmt, args); - va_end(args); - return ret; + struct trace_array *tr = inode->i_private; + + /* disable tracing ? */ + if (trace_flags & TRACE_ITER_STOP_ON_FREE) + tracer_tracing_off(tr); + /* resize the ring buffer to 0 */ + tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); + + trace_array_put(tr); + + return 0; } static ssize_t tracing_mark_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *fpos) { - char *buf; - char *end; + unsigned long addr = (unsigned long)ubuf; + struct trace_array *tr = filp->private_data; + struct ring_buffer_event *event; + struct ring_buffer *buffer; + struct print_entry *entry; + unsigned long irq_flags; + struct page *pages[2]; + void *map_page[2]; + int nr_pages = 1; + ssize_t written; + int offset; + int size; + int len; + int ret; + int i; if (tracing_disabled) return -EINVAL; + if (!(trace_flags & TRACE_ITER_MARKERS)) + return -EINVAL; + if (cnt > TRACE_BUF_SIZE) cnt = TRACE_BUF_SIZE; - buf = kmalloc(cnt + 1, GFP_KERNEL); - if (buf == NULL) - return -ENOMEM; + /* + * Userspace is injecting traces into the kernel trace buffer. + * We want to be as non intrusive as possible. + * To do so, we do not want to allocate any special buffers + * or take any locks, but instead write the userspace data + * straight into the ring buffer. + * + * First we need to pin the userspace buffer into memory, + * which, most likely it is, because it just referenced it. + * But there's no guarantee that it is. By using get_user_pages_fast() + * and kmap_atomic/kunmap_atomic() we can get access to the + * pages directly. We then write the data directly into the + * ring buffer. + */ + BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); - if (copy_from_user(buf, ubuf, cnt)) { - kfree(buf); - return -EFAULT; + /* check if we cross pages */ + if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) + nr_pages = 2; + + offset = addr & (PAGE_SIZE - 1); + addr &= PAGE_MASK; + + ret = get_user_pages_fast(addr, nr_pages, 0, pages); + if (ret < nr_pages) { + while (--ret >= 0) + put_page(pages[ret]); + written = -EFAULT; + goto out; + } + + for (i = 0; i < nr_pages; i++) + map_page[i] = kmap_atomic(pages[i]); + + local_save_flags(irq_flags); + size = sizeof(*entry) + cnt + 2; /* possible \n added */ + buffer = tr->trace_buffer.buffer; + event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, + irq_flags, preempt_count()); + if (!event) { + /* Ring buffer disabled, return as if not open for write */ + written = -EBADF; + goto out_unlock; + } + + entry = ring_buffer_event_data(event); + entry->ip = _THIS_IP_; + + if (nr_pages == 2) { + len = PAGE_SIZE - offset; + memcpy(&entry->buf, map_page[0] + offset, len); + memcpy(&entry->buf[len], map_page[1], cnt - len); + } else + memcpy(&entry->buf, map_page[0] + offset, cnt); + + if (entry->buf[cnt - 1] != '\n') { + entry->buf[cnt] = '\n'; + entry->buf[cnt + 1] = '\0'; + } else + entry->buf[cnt] = '\0'; + + __buffer_unlock_commit(buffer, event); + + written = cnt; + + *fpos += written; + + out_unlock: + for (i = 0; i < nr_pages; i++){ + kunmap_atomic(map_page[i]); + put_page(pages[i]); + } + out: + return written; +} + +static int tracing_clock_show(struct seq_file *m, void *v) +{ + struct trace_array *tr = m->private; + int i; + + for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) + seq_printf(m, + "%s%s%s%s", i ? " " : "", + i == tr->clock_id ? "[" : "", trace_clocks[i].name, + i == tr->clock_id ? "]" : ""); + seq_putc(m, '\n'); + + return 0; +} + +static int tracing_set_clock(struct trace_array *tr, const char *clockstr) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { + if (strcmp(trace_clocks[i].name, clockstr) == 0) + break; } + if (i == ARRAY_SIZE(trace_clocks)) + return -EINVAL; + + mutex_lock(&trace_types_lock); + + tr->clock_id = i; + + ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); + + /* + * New clock may not be consistent with the previous clock. + * Reset the buffer so that it doesn't have incomparable timestamps. + */ + tracing_reset_online_cpus(&tr->trace_buffer); + +#ifdef CONFIG_TRACER_MAX_TRACE + if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) + ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); + tracing_reset_online_cpus(&tr->max_buffer); +#endif + + mutex_unlock(&trace_types_lock); - /* Cut from the first nil or newline. */ - buf[cnt] = '\0'; - end = strchr(buf, '\n'); - if (end) - *end = '\0'; + return 0; +} + +static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *fpos) +{ + struct seq_file *m = filp->private_data; + struct trace_array *tr = m->private; + char buf[64]; + const char *clockstr; + int ret; + + if (cnt >= sizeof(buf)) + return -EINVAL; + + if (copy_from_user(&buf, ubuf, cnt)) + return -EFAULT; + + buf[cnt] = 0; + + clockstr = strstrip(buf); + + ret = tracing_set_clock(tr, clockstr); + if (ret) + return ret; - cnt = mark_printk("%s\n", buf); - kfree(buf); *fpos += cnt; return cnt; } +static int tracing_clock_open(struct inode *inode, struct file *file) +{ + struct trace_array *tr = inode->i_private; + int ret; + + if (tracing_disabled) + return -ENODEV; + + if (trace_array_get(tr)) + return -ENODEV; + + ret = single_open(file, tracing_clock_show, inode->i_private); + if (ret < 0) + trace_array_put(tr); + + return ret; +} + +struct ftrace_buffer_info { + struct trace_iterator iter; + void *spare; + unsigned int read; +}; + +#ifdef CONFIG_TRACER_SNAPSHOT +static int tracing_snapshot_open(struct inode *inode, struct file *file) +{ + struct trace_array *tr = inode->i_private; + struct trace_iterator *iter; + struct seq_file *m; + int ret = 0; + + if (trace_array_get(tr) < 0) + return -ENODEV; + + if (file->f_mode & FMODE_READ) { + iter = __tracing_open(inode, file, true); + if (IS_ERR(iter)) + ret = PTR_ERR(iter); + } else { + /* Writes still need the seq_file to hold the private data */ + ret = -ENOMEM; + m = kzalloc(sizeof(*m), GFP_KERNEL); + if (!m) + goto out; + iter = kzalloc(sizeof(*iter), GFP_KERNEL); + if (!iter) { + kfree(m); + goto out; + } + ret = 0; + + iter->tr = tr; + iter->trace_buffer = &tr->max_buffer; + iter->cpu_file = tracing_get_cpu(inode); + m->private = iter; + file->private_data = m; + } +out: + if (ret < 0) + trace_array_put(tr); + + return ret; +} + +static ssize_t +tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, + loff_t *ppos) +{ + struct seq_file *m = filp->private_data; + struct trace_iterator *iter = m->private; + struct trace_array *tr = iter->tr; + unsigned long val; + int ret; + + ret = tracing_update_buffers(); + if (ret < 0) + return ret; + + ret = kstrtoul_from_user(ubuf, cnt, 10, &val); + if (ret) + return ret; + + mutex_lock(&trace_types_lock); + + if (tr->current_trace->use_max_tr) { + ret = -EBUSY; + goto out; + } + + switch (val) { + case 0: + if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { + ret = -EINVAL; + break; + } + if (tr->allocated_snapshot) + free_snapshot(tr); + break; + case 1: +/* Only allow per-cpu swap if the ring buffer supports it */ +#ifndef CONFIG_RING_BUFFER_ALLOW_SWAP + if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { + ret = -EINVAL; + break; + } +#endif + if (!tr->allocated_snapshot) { + ret = alloc_snapshot(tr); + if (ret < 0) + break; + } + local_irq_disable(); + /* Now, we're going to swap */ + if (iter->cpu_file == RING_BUFFER_ALL_CPUS) + update_max_tr(tr, current, smp_processor_id()); + else + update_max_tr_single(tr, current, iter->cpu_file); + local_irq_enable(); + break; + default: + if (tr->allocated_snapshot) { + if (iter->cpu_file == RING_BUFFER_ALL_CPUS) + tracing_reset_online_cpus(&tr->max_buffer); + else + tracing_reset(&tr->max_buffer, iter->cpu_file); + } + break; + } + + if (ret >= 0) { + *ppos += cnt; + ret = cnt; + } +out: + mutex_unlock(&trace_types_lock); + return ret; +} + +static int tracing_snapshot_release(struct inode *inode, struct file *file) +{ + struct seq_file *m = file->private_data; + int ret; + + ret = tracing_release(inode, file); + + if (file->f_mode & FMODE_READ) + return ret; + + /* If write only, the seq_file is just a stub */ + if (m) + kfree(m->private); + kfree(m); + + return 0; +} + +static int tracing_buffers_open(struct inode *inode, struct file *filp); +static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, + size_t count, loff_t *ppos); +static int tracing_buffers_release(struct inode *inode, struct file *file); +static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, + struct pipe_inode_info *pipe, size_t len, unsigned int flags); + +static int snapshot_raw_open(struct inode *inode, struct file *filp) +{ + struct ftrace_buffer_info *info; + int ret; + + ret = tracing_buffers_open(inode, filp); + if (ret < 0) + return ret; + + info = filp->private_data; + + if (info->iter.trace->use_max_tr) { + tracing_buffers_release(inode, filp); + return -EBUSY; + } + + info->iter.snapshot = true; + info->iter.trace_buffer = &info->iter.tr->max_buffer; + + return ret; +} + +#endif /* CONFIG_TRACER_SNAPSHOT */ + + static const struct file_operations tracing_max_lat_fops = { .open = tracing_open_generic, .read = tracing_max_lat_read, .write = tracing_max_lat_write, -}; - -static const struct file_operations tracing_ctrl_fops = { - .open = tracing_open_generic, - .read = tracing_ctrl_read, - .write = tracing_ctrl_write, + .llseek = generic_file_llseek, }; static const struct file_operations set_tracer_fops = { .open = tracing_open_generic, .read = tracing_set_trace_read, .write = tracing_set_trace_write, + .llseek = generic_file_llseek, }; static const struct file_operations tracing_pipe_fops = { @@ -3337,47 +5190,110 @@ static const struct file_operations tracing_pipe_fops = { .read = tracing_read_pipe, .splice_read = tracing_splice_read_pipe, .release = tracing_release_pipe, + .llseek = no_llseek, }; static const struct file_operations tracing_entries_fops = { - .open = tracing_open_generic, + .open = tracing_open_generic_tr, .read = tracing_entries_read, .write = tracing_entries_write, + .llseek = generic_file_llseek, + .release = tracing_release_generic_tr, +}; + +static const struct file_operations tracing_total_entries_fops = { + .open = tracing_open_generic_tr, + .read = tracing_total_entries_read, + .llseek = generic_file_llseek, + .release = tracing_release_generic_tr, +}; + +static const struct file_operations tracing_free_buffer_fops = { + .open = tracing_open_generic_tr, + .write = tracing_free_buffer_write, + .release = tracing_free_buffer_release, }; static const struct file_operations tracing_mark_fops = { - .open = tracing_open_generic, + .open = tracing_open_generic_tr, .write = tracing_mark_write, + .llseek = generic_file_llseek, + .release = tracing_release_generic_tr, }; -struct ftrace_buffer_info { - struct trace_array *tr; - void *spare; - int cpu; - unsigned int read; +static const struct file_operations trace_clock_fops = { + .open = tracing_clock_open, + .read = seq_read, + .llseek = seq_lseek, + .release = tracing_single_release_tr, + .write = tracing_clock_write, }; +#ifdef CONFIG_TRACER_SNAPSHOT +static const struct file_operations snapshot_fops = { + .open = tracing_snapshot_open, + .read = seq_read, + .write = tracing_snapshot_write, + .llseek = tracing_lseek, + .release = tracing_snapshot_release, +}; + +static const struct file_operations snapshot_raw_fops = { + .open = snapshot_raw_open, + .read = tracing_buffers_read, + .release = tracing_buffers_release, + .splice_read = tracing_buffers_splice_read, + .llseek = no_llseek, +}; + +#endif /* CONFIG_TRACER_SNAPSHOT */ + static int tracing_buffers_open(struct inode *inode, struct file *filp) { - int cpu = (int)(long)inode->i_private; + struct trace_array *tr = inode->i_private; struct ftrace_buffer_info *info; + int ret; if (tracing_disabled) return -ENODEV; + if (trace_array_get(tr) < 0) + return -ENODEV; + info = kzalloc(sizeof(*info), GFP_KERNEL); - if (!info) + if (!info) { + trace_array_put(tr); return -ENOMEM; + } - info->tr = &global_trace; - info->cpu = cpu; - info->spare = NULL; + mutex_lock(&trace_types_lock); + + info->iter.tr = tr; + info->iter.cpu_file = tracing_get_cpu(inode); + info->iter.trace = tr->current_trace; + info->iter.trace_buffer = &tr->trace_buffer; + info->spare = NULL; /* Force reading ring buffer for first read */ - info->read = (unsigned int)-1; + info->read = (unsigned int)-1; filp->private_data = info; - return nonseekable_open(inode, filp); + mutex_unlock(&trace_types_lock); + + ret = nonseekable_open(inode, filp); + if (ret < 0) + trace_array_put(tr); + + return ret; +} + +static unsigned int +tracing_buffers_poll(struct file *filp, poll_table *poll_table) +{ + struct ftrace_buffer_info *info = filp->private_data; + struct trace_iterator *iter = &info->iter; + + return trace_poll(iter, filp, poll_table); } static ssize_t @@ -3385,60 +5301,101 @@ tracing_buffers_read(struct file *filp, char __user *ubuf, size_t count, loff_t *ppos) { struct ftrace_buffer_info *info = filp->private_data; - unsigned int pos; + struct trace_iterator *iter = &info->iter; ssize_t ret; - size_t size; + ssize_t size; if (!count) return 0; + mutex_lock(&trace_types_lock); + +#ifdef CONFIG_TRACER_MAX_TRACE + if (iter->snapshot && iter->tr->current_trace->use_max_tr) { + size = -EBUSY; + goto out_unlock; + } +#endif + if (!info->spare) - info->spare = ring_buffer_alloc_read_page(info->tr->buffer); + info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, + iter->cpu_file); + size = -ENOMEM; if (!info->spare) - return -ENOMEM; + goto out_unlock; /* Do we have previous read data to read? */ if (info->read < PAGE_SIZE) goto read; - info->read = 0; - - ret = ring_buffer_read_page(info->tr->buffer, + again: + trace_access_lock(iter->cpu_file); + ret = ring_buffer_read_page(iter->trace_buffer->buffer, &info->spare, count, - info->cpu, 0); - if (ret < 0) - return 0; + iter->cpu_file, 0); + trace_access_unlock(iter->cpu_file); - pos = ring_buffer_page_len(info->spare); - - if (pos < PAGE_SIZE) - memset(info->spare + pos, 0, PAGE_SIZE - pos); + if (ret < 0) { + if (trace_empty(iter)) { + if ((filp->f_flags & O_NONBLOCK)) { + size = -EAGAIN; + goto out_unlock; + } + mutex_unlock(&trace_types_lock); + ret = wait_on_pipe(iter); + mutex_lock(&trace_types_lock); + if (ret) { + size = ret; + goto out_unlock; + } + if (signal_pending(current)) { + size = -EINTR; + goto out_unlock; + } + goto again; + } + size = 0; + goto out_unlock; + } -read: + info->read = 0; + read: size = PAGE_SIZE - info->read; if (size > count) size = count; ret = copy_to_user(ubuf, info->spare + info->read, size); - if (ret == size) - return -EFAULT; + if (ret == size) { + size = -EFAULT; + goto out_unlock; + } size -= ret; *ppos += size; info->read += size; + out_unlock: + mutex_unlock(&trace_types_lock); + return size; } static int tracing_buffers_release(struct inode *inode, struct file *file) { struct ftrace_buffer_info *info = file->private_data; + struct trace_iterator *iter = &info->iter; + + mutex_lock(&trace_types_lock); + + __trace_array_put(iter->tr); if (info->spare) - ring_buffer_free_read_page(info->tr->buffer, info->spare); + ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); kfree(info); + mutex_unlock(&trace_types_lock); + return 0; } @@ -3461,12 +5418,6 @@ static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, buf->private = 0; } -static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, - struct pipe_buffer *buf) -{ - return 1; -} - static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, struct pipe_buffer *buf) { @@ -3476,13 +5427,11 @@ static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, } /* Pipe buffer operations for a buffer. */ -static struct pipe_buf_operations buffer_pipe_buf_ops = { +static const struct pipe_buf_operations buffer_pipe_buf_ops = { .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, .release = buffer_pipe_buf_release, - .steal = buffer_pipe_buf_steal, + .steal = generic_pipe_buf_steal, .get = buffer_pipe_buf_get, }; @@ -3509,34 +5458,53 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, unsigned int flags) { struct ftrace_buffer_info *info = file->private_data; - struct partial_page partial[PIPE_BUFFERS]; - struct page *pages[PIPE_BUFFERS]; + struct trace_iterator *iter = &info->iter; + struct partial_page partial_def[PIPE_DEF_BUFFERS]; + struct page *pages_def[PIPE_DEF_BUFFERS]; struct splice_pipe_desc spd = { - .pages = pages, - .partial = partial, + .pages = pages_def, + .partial = partial_def, + .nr_pages_max = PIPE_DEF_BUFFERS, .flags = flags, .ops = &buffer_pipe_buf_ops, .spd_release = buffer_spd_release, }; struct buffer_ref *ref; int entries, size, i; - size_t ret; + ssize_t ret; + + mutex_lock(&trace_types_lock); + +#ifdef CONFIG_TRACER_MAX_TRACE + if (iter->snapshot && iter->tr->current_trace->use_max_tr) { + ret = -EBUSY; + goto out; + } +#endif + + if (splice_grow_spd(pipe, &spd)) { + ret = -ENOMEM; + goto out; + } if (*ppos & (PAGE_SIZE - 1)) { - WARN_ONCE(1, "Ftrace: previous read must page-align\n"); - return -EINVAL; + ret = -EINVAL; + goto out; } if (len & (PAGE_SIZE - 1)) { - WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); - if (len < PAGE_SIZE) - return -EINVAL; + if (len < PAGE_SIZE) { + ret = -EINVAL; + goto out; + } len &= PAGE_MASK; } - entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); + again: + trace_access_lock(iter->cpu_file); + entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); - for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) { + for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { struct page *page; int r; @@ -3545,18 +5513,17 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, break; ref->ref = 1; - ref->buffer = info->tr->buffer; - ref->page = ring_buffer_alloc_read_page(ref->buffer); + ref->buffer = iter->trace_buffer->buffer; + ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); if (!ref->page) { kfree(ref); break; } r = ring_buffer_read_page(ref->buffer, &ref->page, - len, info->cpu, 1); + len, iter->cpu_file, 1); if (r < 0) { - ring_buffer_free_read_page(ref->buffer, - ref->page); + ring_buffer_free_read_page(ref->buffer, ref->page); kfree(ref); break; } @@ -3578,22 +5545,34 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, spd.nr_pages++; *ppos += PAGE_SIZE; - entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); + entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); } + trace_access_unlock(iter->cpu_file); spd.nr_pages = i; /* did we read anything? */ if (!spd.nr_pages) { - if (flags & SPLICE_F_NONBLOCK) + if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) { ret = -EAGAIN; - else - ret = 0; - /* TODO: block */ - return ret; + goto out; + } + mutex_unlock(&trace_types_lock); + ret = wait_on_pipe(iter); + mutex_lock(&trace_types_lock); + if (ret) + goto out; + if (signal_pending(current)) { + ret = -EINTR; + goto out; + } + goto again; } ret = splice_to_pipe(pipe, &spd); + splice_shrink_spd(&spd); +out: + mutex_unlock(&trace_types_lock); return ret; } @@ -3601,6 +5580,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, static const struct file_operations tracing_buffers_fops = { .open = tracing_buffers_open, .read = tracing_buffers_read, + .poll = tracing_buffers_poll, .release = tracing_buffers_release, .splice_read = tracing_buffers_splice_read, .llseek = no_llseek, @@ -3610,28 +5590,57 @@ static ssize_t tracing_stats_read(struct file *filp, char __user *ubuf, size_t count, loff_t *ppos) { - unsigned long cpu = (unsigned long)filp->private_data; - struct trace_array *tr = &global_trace; + struct inode *inode = file_inode(filp); + struct trace_array *tr = inode->i_private; + struct trace_buffer *trace_buf = &tr->trace_buffer; + int cpu = tracing_get_cpu(inode); struct trace_seq *s; unsigned long cnt; + unsigned long long t; + unsigned long usec_rem; s = kmalloc(sizeof(*s), GFP_KERNEL); if (!s) - return ENOMEM; + return -ENOMEM; trace_seq_init(s); - cnt = ring_buffer_entries_cpu(tr->buffer, cpu); + cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); trace_seq_printf(s, "entries: %ld\n", cnt); - cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); + cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); trace_seq_printf(s, "overrun: %ld\n", cnt); - cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); + cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); trace_seq_printf(s, "commit overrun: %ld\n", cnt); - cnt = ring_buffer_nmi_dropped_cpu(tr->buffer, cpu); - trace_seq_printf(s, "nmi dropped: %ld\n", cnt); + cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); + trace_seq_printf(s, "bytes: %ld\n", cnt); + + if (trace_clocks[tr->clock_id].in_ns) { + /* local or global for trace_clock */ + t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); + usec_rem = do_div(t, USEC_PER_SEC); + trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", + t, usec_rem); + + t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); + usec_rem = do_div(t, USEC_PER_SEC); + trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); + } else { + /* counter or tsc mode for trace_clock */ + trace_seq_printf(s, "oldest event ts: %llu\n", + ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); + + trace_seq_printf(s, "now ts: %llu\n", + ring_buffer_time_stamp(trace_buf->buffer, cpu)); + } + + cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); + trace_seq_printf(s, "dropped events: %ld\n", cnt); + + cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); + trace_seq_printf(s, "read events: %ld\n", cnt); count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); @@ -3641,8 +5650,10 @@ tracing_stats_read(struct file *filp, char __user *ubuf, } static const struct file_operations tracing_stats_fops = { - .open = tracing_open_generic, + .open = tracing_open_generic_tr, .read = tracing_stats_read, + .llseek = generic_file_llseek, + .release = tracing_release_generic_tr, }; #ifdef CONFIG_DYNAMIC_FTRACE @@ -3679,69 +5690,180 @@ tracing_read_dyn_info(struct file *filp, char __user *ubuf, static const struct file_operations tracing_dyn_info_fops = { .open = tracing_open_generic, .read = tracing_read_dyn_info, + .llseek = generic_file_llseek, }; -#endif +#endif /* CONFIG_DYNAMIC_FTRACE */ + +#if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) +static void +ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data) +{ + tracing_snapshot(); +} -static struct dentry *d_tracer; +static void +ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data) +{ + unsigned long *count = (long *)data; -struct dentry *tracing_init_dentry(void) + if (!*count) + return; + + if (*count != -1) + (*count)--; + + tracing_snapshot(); +} + +static int +ftrace_snapshot_print(struct seq_file *m, unsigned long ip, + struct ftrace_probe_ops *ops, void *data) +{ + long count = (long)data; + + seq_printf(m, "%ps:", (void *)ip); + + seq_printf(m, "snapshot"); + + if (count == -1) + seq_printf(m, ":unlimited\n"); + else + seq_printf(m, ":count=%ld\n", count); + + return 0; +} + +static struct ftrace_probe_ops snapshot_probe_ops = { + .func = ftrace_snapshot, + .print = ftrace_snapshot_print, +}; + +static struct ftrace_probe_ops snapshot_count_probe_ops = { + .func = ftrace_count_snapshot, + .print = ftrace_snapshot_print, +}; + +static int +ftrace_trace_snapshot_callback(struct ftrace_hash *hash, + char *glob, char *cmd, char *param, int enable) +{ + struct ftrace_probe_ops *ops; + void *count = (void *)-1; + char *number; + int ret; + + /* hash funcs only work with set_ftrace_filter */ + if (!enable) + return -EINVAL; + + ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; + + if (glob[0] == '!') { + unregister_ftrace_function_probe_func(glob+1, ops); + return 0; + } + + if (!param) + goto out_reg; + + number = strsep(¶m, ":"); + + if (!strlen(number)) + goto out_reg; + + /* + * We use the callback data field (which is a pointer) + * as our counter. + */ + ret = kstrtoul(number, 0, (unsigned long *)&count); + if (ret) + return ret; + + out_reg: + ret = register_ftrace_function_probe(glob, ops, count); + + if (ret >= 0) + alloc_snapshot(&global_trace); + + return ret < 0 ? ret : 0; +} + +static struct ftrace_func_command ftrace_snapshot_cmd = { + .name = "snapshot", + .func = ftrace_trace_snapshot_callback, +}; + +static __init int register_snapshot_cmd(void) { - static int once; + return register_ftrace_command(&ftrace_snapshot_cmd); +} +#else +static inline __init int register_snapshot_cmd(void) { return 0; } +#endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ - if (d_tracer) - return d_tracer; +struct dentry *tracing_init_dentry_tr(struct trace_array *tr) +{ + if (tr->dir) + return tr->dir; if (!debugfs_initialized()) return NULL; - d_tracer = debugfs_create_dir("tracing", NULL); + if (tr->flags & TRACE_ARRAY_FL_GLOBAL) + tr->dir = debugfs_create_dir("tracing", NULL); - if (!d_tracer && !once) { - once = 1; - pr_warning("Could not create debugfs directory 'tracing'\n"); - return NULL; - } + if (!tr->dir) + pr_warn_once("Could not create debugfs directory 'tracing'\n"); - return d_tracer; + return tr->dir; } -static struct dentry *d_percpu; +struct dentry *tracing_init_dentry(void) +{ + return tracing_init_dentry_tr(&global_trace); +} -struct dentry *tracing_dentry_percpu(void) +static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) { - static int once; struct dentry *d_tracer; - if (d_percpu) - return d_percpu; - - d_tracer = tracing_init_dentry(); + if (tr->percpu_dir) + return tr->percpu_dir; + d_tracer = tracing_init_dentry_tr(tr); if (!d_tracer) return NULL; - d_percpu = debugfs_create_dir("per_cpu", d_tracer); + tr->percpu_dir = debugfs_create_dir("per_cpu", d_tracer); - if (!d_percpu && !once) { - once = 1; - pr_warning("Could not create debugfs directory 'per_cpu'\n"); - return NULL; - } + WARN_ONCE(!tr->percpu_dir, + "Could not create debugfs directory 'per_cpu/%d'\n", cpu); - return d_percpu; + return tr->percpu_dir; } -static void tracing_init_debugfs_percpu(long cpu) +static struct dentry * +trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, + void *data, long cpu, const struct file_operations *fops) +{ + struct dentry *ret = trace_create_file(name, mode, parent, data, fops); + + if (ret) /* See tracing_get_cpu() */ + ret->d_inode->i_cdev = (void *)(cpu + 1); + return ret; +} + +static void +tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) { - struct dentry *d_percpu = tracing_dentry_percpu(); + struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); struct dentry *d_cpu; - /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ - char cpu_dir[7]; + char cpu_dir[30]; /* 30 characters should be more than enough */ - if (cpu > 999 || cpu < 0) + if (!d_percpu) return; - sprintf(cpu_dir, "cpu%ld", cpu); + snprintf(cpu_dir, 30, "cpu%ld", cpu); d_cpu = debugfs_create_dir(cpu_dir, d_percpu); if (!d_cpu) { pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); @@ -3749,18 +5871,29 @@ static void tracing_init_debugfs_percpu(long cpu) } /* per cpu trace_pipe */ - trace_create_file("trace_pipe", 0444, d_cpu, - (void *) cpu, &tracing_pipe_fops); + trace_create_cpu_file("trace_pipe", 0444, d_cpu, + tr, cpu, &tracing_pipe_fops); /* per cpu trace */ - trace_create_file("trace", 0644, d_cpu, - (void *) cpu, &tracing_fops); + trace_create_cpu_file("trace", 0644, d_cpu, + tr, cpu, &tracing_fops); - trace_create_file("trace_pipe_raw", 0444, d_cpu, - (void *) cpu, &tracing_buffers_fops); + trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, + tr, cpu, &tracing_buffers_fops); - trace_create_file("stats", 0444, d_cpu, - (void *) cpu, &tracing_stats_fops); + trace_create_cpu_file("stats", 0444, d_cpu, + tr, cpu, &tracing_stats_fops); + + trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, + tr, cpu, &tracing_entries_fops); + +#ifdef CONFIG_TRACER_SNAPSHOT + trace_create_cpu_file("snapshot", 0644, d_cpu, + tr, cpu, &snapshot_fops); + + trace_create_cpu_file("snapshot_raw", 0444, d_cpu, + tr, cpu, &snapshot_raw_fops); +#endif } #ifdef CONFIG_FTRACE_SELFTEST @@ -3771,6 +5904,7 @@ static void tracing_init_debugfs_percpu(long cpu) struct trace_option_dentry { struct tracer_opt *opt; struct tracer_flags *flags; + struct trace_array *tr; struct dentry *entry; }; @@ -3795,54 +5929,22 @@ trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, { struct trace_option_dentry *topt = filp->private_data; unsigned long val; - char buf[64]; int ret; - if (cnt >= sizeof(buf)) - return -EINVAL; - - if (copy_from_user(&buf, ubuf, cnt)) - return -EFAULT; - - buf[cnt] = 0; - - ret = strict_strtoul(buf, 10, &val); - if (ret < 0) + ret = kstrtoul_from_user(ubuf, cnt, 10, &val); + if (ret) return ret; - ret = 0; - switch (val) { - case 0: - /* do nothing if already cleared */ - if (!(topt->flags->val & topt->opt->bit)) - break; - - mutex_lock(&trace_types_lock); - if (current_trace->set_flag) - ret = current_trace->set_flag(topt->flags->val, - topt->opt->bit, 0); - mutex_unlock(&trace_types_lock); - if (ret) - return ret; - topt->flags->val &= ~topt->opt->bit; - break; - case 1: - /* do nothing if already set */ - if (topt->flags->val & topt->opt->bit) - break; + if (val != 0 && val != 1) + return -EINVAL; + if (!!(topt->flags->val & topt->opt->bit) != val) { mutex_lock(&trace_types_lock); - if (current_trace->set_flag) - ret = current_trace->set_flag(topt->flags->val, - topt->opt->bit, 1); + ret = __set_tracer_option(topt->tr, topt->flags, + topt->opt, !val); mutex_unlock(&trace_types_lock); if (ret) return ret; - topt->flags->val |= topt->opt->bit; - break; - - default: - return -EINVAL; } *ppos += cnt; @@ -3855,6 +5957,7 @@ static const struct file_operations trace_options_fops = { .open = tracing_open_generic, .read = trace_options_read, .write = trace_options_write, + .llseek = generic_file_llseek, }; static ssize_t @@ -3876,35 +5979,25 @@ static ssize_t trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { + struct trace_array *tr = &global_trace; long index = (long)filp->private_data; - char buf[64]; unsigned long val; int ret; - if (cnt >= sizeof(buf)) - return -EINVAL; + ret = kstrtoul_from_user(ubuf, cnt, 10, &val); + if (ret) + return ret; - if (copy_from_user(&buf, ubuf, cnt)) - return -EFAULT; + if (val != 0 && val != 1) + return -EINVAL; - buf[cnt] = 0; + mutex_lock(&trace_types_lock); + ret = set_tracer_flag(tr, 1 << index, val); + mutex_unlock(&trace_types_lock); - ret = strict_strtoul(buf, 10, &val); if (ret < 0) return ret; - switch (val) { - case 0: - trace_flags &= ~(1 << index); - break; - case 1: - trace_flags |= 1 << index; - break; - - default: - return -EINVAL; - } - *ppos += cnt; return cnt; @@ -3914,10 +6007,11 @@ static const struct file_operations trace_options_core_fops = { .open = tracing_open_generic, .read = trace_options_core_read, .write = trace_options_core_write, + .llseek = generic_file_llseek, }; struct dentry *trace_create_file(const char *name, - mode_t mode, + umode_t mode, struct dentry *parent, void *data, const struct file_operations *fops) @@ -3932,40 +6026,41 @@ struct dentry *trace_create_file(const char *name, } -static struct dentry *trace_options_init_dentry(void) +static struct dentry *trace_options_init_dentry(struct trace_array *tr) { struct dentry *d_tracer; - static struct dentry *t_options; - if (t_options) - return t_options; + if (tr->options) + return tr->options; - d_tracer = tracing_init_dentry(); + d_tracer = tracing_init_dentry_tr(tr); if (!d_tracer) return NULL; - t_options = debugfs_create_dir("options", d_tracer); - if (!t_options) { + tr->options = debugfs_create_dir("options", d_tracer); + if (!tr->options) { pr_warning("Could not create debugfs directory 'options'\n"); return NULL; } - return t_options; + return tr->options; } static void -create_trace_option_file(struct trace_option_dentry *topt, +create_trace_option_file(struct trace_array *tr, + struct trace_option_dentry *topt, struct tracer_flags *flags, struct tracer_opt *opt) { struct dentry *t_options; - t_options = trace_options_init_dentry(); + t_options = trace_options_init_dentry(tr); if (!t_options) return; topt->flags = flags; topt->opt = opt; + topt->tr = tr; topt->entry = trace_create_file(opt->name, 0644, t_options, topt, &trace_options_fops); @@ -3973,7 +6068,7 @@ create_trace_option_file(struct trace_option_dentry *topt, } static struct trace_option_dentry * -create_trace_option_files(struct tracer *tracer) +create_trace_option_files(struct trace_array *tr, struct tracer *tracer) { struct trace_option_dentry *topts; struct tracer_flags *flags; @@ -3998,7 +6093,7 @@ create_trace_option_files(struct tracer *tracer) return NULL; for (cnt = 0; opts[cnt].name; cnt++) - create_trace_option_file(&topts[cnt], flags, + create_trace_option_file(tr, &topts[cnt], flags, &opts[cnt]); return topts; @@ -4021,11 +6116,12 @@ destroy_trace_option_files(struct trace_option_dentry *topts) } static struct dentry * -create_trace_option_core_file(const char *option, long index) +create_trace_option_core_file(struct trace_array *tr, + const char *option, long index) { struct dentry *t_options; - t_options = trace_options_init_dentry(); + t_options = trace_options_init_dentry(tr); if (!t_options) return NULL; @@ -4033,77 +6129,429 @@ create_trace_option_core_file(const char *option, long index) &trace_options_core_fops); } -static __init void create_trace_options_dir(void) +static __init void create_trace_options_dir(struct trace_array *tr) { struct dentry *t_options; int i; - t_options = trace_options_init_dentry(); + t_options = trace_options_init_dentry(tr); if (!t_options) return; for (i = 0; trace_options[i]; i++) - create_trace_option_core_file(trace_options[i], i); + create_trace_option_core_file(tr, trace_options[i], i); } -static __init int tracer_init_debugfs(void) +static ssize_t +rb_simple_read(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) { - struct dentry *d_tracer; - int cpu; + struct trace_array *tr = filp->private_data; + char buf[64]; + int r; - d_tracer = tracing_init_dentry(); + r = tracer_tracing_is_on(tr); + r = sprintf(buf, "%d\n", r); - trace_create_file("tracing_enabled", 0644, d_tracer, - &global_trace, &tracing_ctrl_fops); + return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); +} - trace_create_file("trace_options", 0644, d_tracer, - NULL, &tracing_iter_fops); +static ssize_t +rb_simple_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + struct trace_array *tr = filp->private_data; + struct ring_buffer *buffer = tr->trace_buffer.buffer; + unsigned long val; + int ret; - trace_create_file("tracing_cpumask", 0644, d_tracer, - NULL, &tracing_cpumask_fops); + ret = kstrtoul_from_user(ubuf, cnt, 10, &val); + if (ret) + return ret; - trace_create_file("trace", 0644, d_tracer, - (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); + if (buffer) { + mutex_lock(&trace_types_lock); + if (val) { + tracer_tracing_on(tr); + if (tr->current_trace->start) + tr->current_trace->start(tr); + } else { + tracer_tracing_off(tr); + if (tr->current_trace->stop) + tr->current_trace->stop(tr); + } + mutex_unlock(&trace_types_lock); + } + + (*ppos)++; + + return cnt; +} + +static const struct file_operations rb_simple_fops = { + .open = tracing_open_generic_tr, + .read = rb_simple_read, + .write = rb_simple_write, + .release = tracing_release_generic_tr, + .llseek = default_llseek, +}; + +struct dentry *trace_instance_dir; + +static void +init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer); + +static int +allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) +{ + enum ring_buffer_flags rb_flags; + + rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; + + buf->tr = tr; + + buf->buffer = ring_buffer_alloc(size, rb_flags); + if (!buf->buffer) + return -ENOMEM; + + buf->data = alloc_percpu(struct trace_array_cpu); + if (!buf->data) { + ring_buffer_free(buf->buffer); + return -ENOMEM; + } + + /* Allocate the first page for all buffers */ + set_buffer_entries(&tr->trace_buffer, + ring_buffer_size(tr->trace_buffer.buffer, 0)); + + return 0; +} + +static int allocate_trace_buffers(struct trace_array *tr, int size) +{ + int ret; + + ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); + if (ret) + return ret; + +#ifdef CONFIG_TRACER_MAX_TRACE + ret = allocate_trace_buffer(tr, &tr->max_buffer, + allocate_snapshot ? size : 1); + if (WARN_ON(ret)) { + ring_buffer_free(tr->trace_buffer.buffer); + free_percpu(tr->trace_buffer.data); + return -ENOMEM; + } + tr->allocated_snapshot = allocate_snapshot; + + /* + * Only the top level trace array gets its snapshot allocated + * from the kernel command line. + */ + allocate_snapshot = false; +#endif + return 0; +} + +static void free_trace_buffer(struct trace_buffer *buf) +{ + if (buf->buffer) { + ring_buffer_free(buf->buffer); + buf->buffer = NULL; + free_percpu(buf->data); + buf->data = NULL; + } +} + +static void free_trace_buffers(struct trace_array *tr) +{ + if (!tr) + return; + + free_trace_buffer(&tr->trace_buffer); + +#ifdef CONFIG_TRACER_MAX_TRACE + free_trace_buffer(&tr->max_buffer); +#endif +} + +static int new_instance_create(const char *name) +{ + struct trace_array *tr; + int ret; + + mutex_lock(&trace_types_lock); + + ret = -EEXIST; + list_for_each_entry(tr, &ftrace_trace_arrays, list) { + if (tr->name && strcmp(tr->name, name) == 0) + goto out_unlock; + } + + ret = -ENOMEM; + tr = kzalloc(sizeof(*tr), GFP_KERNEL); + if (!tr) + goto out_unlock; + + tr->name = kstrdup(name, GFP_KERNEL); + if (!tr->name) + goto out_free_tr; + + if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) + goto out_free_tr; + + cpumask_copy(tr->tracing_cpumask, cpu_all_mask); + + raw_spin_lock_init(&tr->start_lock); + + tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; + + tr->current_trace = &nop_trace; + + INIT_LIST_HEAD(&tr->systems); + INIT_LIST_HEAD(&tr->events); + + if (allocate_trace_buffers(tr, trace_buf_size) < 0) + goto out_free_tr; + + tr->dir = debugfs_create_dir(name, trace_instance_dir); + if (!tr->dir) + goto out_free_tr; + + ret = event_trace_add_tracer(tr->dir, tr); + if (ret) { + debugfs_remove_recursive(tr->dir); + goto out_free_tr; + } + + init_tracer_debugfs(tr, tr->dir); + + list_add(&tr->list, &ftrace_trace_arrays); + + mutex_unlock(&trace_types_lock); + + return 0; + + out_free_tr: + free_trace_buffers(tr); + free_cpumask_var(tr->tracing_cpumask); + kfree(tr->name); + kfree(tr); + + out_unlock: + mutex_unlock(&trace_types_lock); + + return ret; + +} + +static int instance_delete(const char *name) +{ + struct trace_array *tr; + int found = 0; + int ret; + + mutex_lock(&trace_types_lock); + + ret = -ENODEV; + list_for_each_entry(tr, &ftrace_trace_arrays, list) { + if (tr->name && strcmp(tr->name, name) == 0) { + found = 1; + break; + } + } + if (!found) + goto out_unlock; + + ret = -EBUSY; + if (tr->ref) + goto out_unlock; + + list_del(&tr->list); + + tracing_set_nop(tr); + event_trace_del_tracer(tr); + ftrace_destroy_function_files(tr); + debugfs_remove_recursive(tr->dir); + free_trace_buffers(tr); + + kfree(tr->name); + kfree(tr); + + ret = 0; + + out_unlock: + mutex_unlock(&trace_types_lock); + + return ret; +} + +static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t mode) +{ + struct dentry *parent; + int ret; + + /* Paranoid: Make sure the parent is the "instances" directory */ + parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); + if (WARN_ON_ONCE(parent != trace_instance_dir)) + return -ENOENT; + + /* + * The inode mutex is locked, but debugfs_create_dir() will also + * take the mutex. As the instances directory can not be destroyed + * or changed in any other way, it is safe to unlock it, and + * let the dentry try. If two users try to make the same dir at + * the same time, then the new_instance_create() will determine the + * winner. + */ + mutex_unlock(&inode->i_mutex); + + ret = new_instance_create(dentry->d_iname); + + mutex_lock(&inode->i_mutex); + + return ret; +} + +static int instance_rmdir(struct inode *inode, struct dentry *dentry) +{ + struct dentry *parent; + int ret; + + /* Paranoid: Make sure the parent is the "instances" directory */ + parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); + if (WARN_ON_ONCE(parent != trace_instance_dir)) + return -ENOENT; + + /* The caller did a dget() on dentry */ + mutex_unlock(&dentry->d_inode->i_mutex); + + /* + * The inode mutex is locked, but debugfs_create_dir() will also + * take the mutex. As the instances directory can not be destroyed + * or changed in any other way, it is safe to unlock it, and + * let the dentry try. If two users try to make the same dir at + * the same time, then the instance_delete() will determine the + * winner. + */ + mutex_unlock(&inode->i_mutex); + + ret = instance_delete(dentry->d_iname); + + mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); + mutex_lock(&dentry->d_inode->i_mutex); + + return ret; +} + +static const struct inode_operations instance_dir_inode_operations = { + .lookup = simple_lookup, + .mkdir = instance_mkdir, + .rmdir = instance_rmdir, +}; + +static __init void create_trace_instances(struct dentry *d_tracer) +{ + trace_instance_dir = debugfs_create_dir("instances", d_tracer); + if (WARN_ON(!trace_instance_dir)) + return; + + /* Hijack the dir inode operations, to allow mkdir */ + trace_instance_dir->d_inode->i_op = &instance_dir_inode_operations; +} + +static void +init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) +{ + int cpu; trace_create_file("available_tracers", 0444, d_tracer, - &global_trace, &show_traces_fops); + tr, &show_traces_fops); trace_create_file("current_tracer", 0644, d_tracer, - &global_trace, &set_tracer_fops); + tr, &set_tracer_fops); - trace_create_file("tracing_max_latency", 0644, d_tracer, - &tracing_max_latency, &tracing_max_lat_fops); + trace_create_file("tracing_cpumask", 0644, d_tracer, + tr, &tracing_cpumask_fops); - trace_create_file("tracing_thresh", 0644, d_tracer, - &tracing_thresh, &tracing_max_lat_fops); + trace_create_file("trace_options", 0644, d_tracer, + tr, &tracing_iter_fops); - trace_create_file("README", 0444, d_tracer, - NULL, &tracing_readme_fops); + trace_create_file("trace", 0644, d_tracer, + tr, &tracing_fops); trace_create_file("trace_pipe", 0444, d_tracer, - (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); + tr, &tracing_pipe_fops); trace_create_file("buffer_size_kb", 0644, d_tracer, - &global_trace, &tracing_entries_fops); + tr, &tracing_entries_fops); + + trace_create_file("buffer_total_size_kb", 0444, d_tracer, + tr, &tracing_total_entries_fops); + + trace_create_file("free_buffer", 0200, d_tracer, + tr, &tracing_free_buffer_fops); trace_create_file("trace_marker", 0220, d_tracer, - NULL, &tracing_mark_fops); + tr, &tracing_mark_fops); + + trace_create_file("trace_clock", 0644, d_tracer, tr, + &trace_clock_fops); + + trace_create_file("tracing_on", 0644, d_tracer, + tr, &rb_simple_fops); + +#ifdef CONFIG_TRACER_MAX_TRACE + trace_create_file("tracing_max_latency", 0644, d_tracer, + &tr->max_latency, &tracing_max_lat_fops); +#endif + + if (ftrace_create_function_files(tr, d_tracer)) + WARN(1, "Could not allocate function filter files"); + +#ifdef CONFIG_TRACER_SNAPSHOT + trace_create_file("snapshot", 0644, d_tracer, + tr, &snapshot_fops); +#endif + + for_each_tracing_cpu(cpu) + tracing_init_debugfs_percpu(tr, cpu); + +} + +static __init int tracer_init_debugfs(void) +{ + struct dentry *d_tracer; + + trace_access_lock_init(); + + d_tracer = tracing_init_dentry(); + if (!d_tracer) + return 0; + + init_tracer_debugfs(&global_trace, d_tracer); + + trace_create_file("tracing_thresh", 0644, d_tracer, + &tracing_thresh, &tracing_max_lat_fops); + + trace_create_file("README", 0444, d_tracer, + NULL, &tracing_readme_fops); trace_create_file("saved_cmdlines", 0444, d_tracer, NULL, &tracing_saved_cmdlines_fops); + trace_create_file("saved_cmdlines_size", 0644, d_tracer, + NULL, &tracing_saved_cmdlines_size_fops); + #ifdef CONFIG_DYNAMIC_FTRACE trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, &ftrace_update_tot_cnt, &tracing_dyn_info_fops); #endif -#ifdef CONFIG_SYSPROF_TRACER - init_tracer_sysprof_debugfs(d_tracer); -#endif - create_trace_options_dir(); + create_trace_instances(d_tracer); - for_each_tracing_cpu(cpu) - tracing_init_debugfs_percpu(cpu); + create_trace_options_dir(&global_trace); return 0; } @@ -4112,7 +6560,7 @@ static int trace_panic_handler(struct notifier_block *this, unsigned long event, void *unused) { if (ftrace_dump_on_oops) - ftrace_dump(); + ftrace_dump(ftrace_dump_on_oops); return NOTIFY_OK; } @@ -4129,7 +6577,7 @@ static int trace_die_handler(struct notifier_block *self, switch (val) { case DIE_OOPS: if (ftrace_dump_on_oops) - ftrace_dump(); + ftrace_dump(ftrace_dump_on_oops); break; default: break; @@ -4155,12 +6603,12 @@ static struct notifier_block trace_die_notifier = { */ #define KERN_TRACE KERN_EMERG -static void +void trace_printk_seq(struct trace_seq *s) { /* Probably should print a warning here. */ - if (s->len >= 1000) - s->len = 1000; + if (s->len >= TRACE_MAX_PRINT) + s->len = TRACE_MAX_PRINT; /* should be zero ended, but we are paranoid. */ s->buffer[s->len] = 0; @@ -4170,32 +6618,57 @@ trace_printk_seq(struct trace_seq *s) trace_seq_init(s); } -static void __ftrace_dump(bool disable_tracing) +void trace_init_global_iter(struct trace_iterator *iter) +{ + iter->tr = &global_trace; + iter->trace = iter->tr->current_trace; + iter->cpu_file = RING_BUFFER_ALL_CPUS; + iter->trace_buffer = &global_trace.trace_buffer; + + if (iter->trace && iter->trace->open) + iter->trace->open(iter); + + /* Annotate start of buffers if we had overruns */ + if (ring_buffer_overruns(iter->trace_buffer->buffer)) + iter->iter_flags |= TRACE_FILE_ANNOTATE; + + /* Output in nanoseconds only if we are using a clock in nanoseconds. */ + if (trace_clocks[iter->tr->clock_id].in_ns) + iter->iter_flags |= TRACE_FILE_TIME_IN_NS; +} + +void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { - static raw_spinlock_t ftrace_dump_lock = - (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; /* use static because iter can be a bit big for the stack */ static struct trace_iterator iter; + static atomic_t dump_running; unsigned int old_userobj; - static int dump_ran; unsigned long flags; int cnt = 0, cpu; - /* only one dump */ - local_irq_save(flags); - __raw_spin_lock(&ftrace_dump_lock); - if (dump_ran) - goto out; - - dump_ran = 1; + /* Only allow one dump user at a time. */ + if (atomic_inc_return(&dump_running) != 1) { + atomic_dec(&dump_running); + return; + } + /* + * Always turn off tracing when we dump. + * We don't need to show trace output of what happens + * between multiple crashes. + * + * If the user does a sysrq-z, then they can re-enable + * tracing with echo 1 > tracing_on. + */ tracing_off(); - if (disable_tracing) - ftrace_kill(); + local_irq_save(flags); + + /* Simulate the iterator */ + trace_init_global_iter(&iter); for_each_tracing_cpu(cpu) { - atomic_inc(&global_trace.data[cpu]->disabled); + atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled); } old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; @@ -4203,12 +6676,27 @@ static void __ftrace_dump(bool disable_tracing) /* don't look at user memory in panic mode */ trace_flags &= ~TRACE_ITER_SYM_USEROBJ; + switch (oops_dump_mode) { + case DUMP_ALL: + iter.cpu_file = RING_BUFFER_ALL_CPUS; + break; + case DUMP_ORIG: + iter.cpu_file = raw_smp_processor_id(); + break; + case DUMP_NONE: + goto out_enable; + default: + printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); + iter.cpu_file = RING_BUFFER_ALL_CPUS; + } + printk(KERN_TRACE "Dumping ftrace buffer:\n"); - /* Simulate the iterator */ - iter.tr = &global_trace; - iter.trace = current_trace; - iter.cpu_file = TRACE_PIPE_ALL_CPU; + /* Did function tracer already get disabled? */ + if (ftrace_is_dead()) { + printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); + printk("# MAY BE MISSING FUNCTION EVENTS\n"); + } /* * We need to stop all tracing on all CPUS to read the @@ -4231,10 +6719,14 @@ static void __ftrace_dump(bool disable_tracing) iter.iter_flags |= TRACE_FILE_LAT_FMT; iter.pos = -1; - if (find_next_entry_inc(&iter) != NULL) { - print_trace_line(&iter); - trace_consume(&iter); + if (trace_find_next_entry_inc(&iter) != NULL) { + int ret; + + ret = print_trace_line(&iter); + if (ret != TRACE_TYPE_NO_CONSUME) + trace_consume(&iter); } + touch_nmi_watchdog(); trace_printk_seq(&iter.seq); } @@ -4244,42 +6736,33 @@ static void __ftrace_dump(bool disable_tracing) else printk(KERN_TRACE "---------------------------------\n"); - /* Re-enable tracing if requested */ - if (!disable_tracing) { - trace_flags |= old_userobj; + out_enable: + trace_flags |= old_userobj; - for_each_tracing_cpu(cpu) { - atomic_dec(&global_trace.data[cpu]->disabled); - } - tracing_on(); + for_each_tracing_cpu(cpu) { + atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); } - - out: - __raw_spin_unlock(&ftrace_dump_lock); + atomic_dec(&dump_running); local_irq_restore(flags); } - -/* By default: disable tracing after the dump */ -void ftrace_dump(void) -{ - __ftrace_dump(true); -} +EXPORT_SYMBOL_GPL(ftrace_dump); __init static int tracer_alloc_buffers(void) { - struct trace_array_cpu *data; int ring_buf_size; - int i; int ret = -ENOMEM; + if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) goto out; - if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) + if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) goto out_free_buffer_mask; - if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) - goto out_free_tracing_cpumask; + /* Only allocate trace_printk buffers if a trace_printk exists */ + if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) + /* Must be called before global_trace.buffer is allocated */ + trace_printk_init_buffers(); /* To save memory, keep the ring buffer size to its minimum */ if (ring_buffer_expanded) @@ -4288,46 +6771,48 @@ __init static int tracer_alloc_buffers(void) ring_buf_size = 1; cpumask_copy(tracing_buffer_mask, cpu_possible_mask); - cpumask_copy(tracing_cpumask, cpu_all_mask); - cpumask_clear(tracing_reader_cpumask); + cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); + + raw_spin_lock_init(&global_trace.start_lock); + + /* Used for event triggers */ + temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); + if (!temp_buffer) + goto out_free_cpumask; + + if (trace_create_savedcmd() < 0) + goto out_free_temp_buffer; /* TODO: make the number of buffers hot pluggable with CPUS */ - global_trace.buffer = ring_buffer_alloc(ring_buf_size, - TRACE_BUFFER_FLAGS); - if (!global_trace.buffer) { + if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); WARN_ON(1); - goto out_free_cpumask; + goto out_free_savedcmd; } - global_trace.entries = ring_buffer_size(global_trace.buffer); + if (global_trace.buffer_disabled) + tracing_off(); -#ifdef CONFIG_TRACER_MAX_TRACE - max_tr.buffer = ring_buffer_alloc(ring_buf_size, - TRACE_BUFFER_FLAGS); - if (!max_tr.buffer) { - printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); - WARN_ON(1); - ring_buffer_free(global_trace.buffer); - goto out_free_cpumask; + if (trace_boot_clock) { + ret = tracing_set_clock(&global_trace, trace_boot_clock); + if (ret < 0) + pr_warning("Trace clock %s not defined, going back to default\n", + trace_boot_clock); } - max_tr.entries = ring_buffer_size(max_tr.buffer); - WARN_ON(max_tr.entries != global_trace.entries); -#endif - /* Allocate the first page for all buffers */ - for_each_tracing_cpu(i) { - data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); - max_tr.data[i] = &per_cpu(max_data, i); - } + /* + * register_tracer() might reference current_trace, so it + * needs to be set before we register anything. This is + * just a bootstrap of current_trace anyway. + */ + global_trace.current_trace = &nop_trace; + + global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; - trace_init_cmdlines(); + ftrace_init_global_array_ops(&global_trace); register_tracer(&nop_trace); - current_trace = &nop_trace; -#ifdef CONFIG_BOOT_TRACER - register_tracer(&boot_tracer); -#endif + /* All seems OK, enable tracing */ tracing_disabled = 0; @@ -4336,12 +6821,29 @@ __init static int tracer_alloc_buffers(void) register_die_notifier(&trace_die_notifier); + global_trace.flags = TRACE_ARRAY_FL_GLOBAL; + + INIT_LIST_HEAD(&global_trace.systems); + INIT_LIST_HEAD(&global_trace.events); + list_add(&global_trace.list, &ftrace_trace_arrays); + + while (trace_boot_options) { + char *option; + + option = strsep(&trace_boot_options, ","); + trace_set_options(&global_trace, option); + } + + register_snapshot_cmd(); + return 0; +out_free_savedcmd: + free_saved_cmdlines_buffer(savedcmd); +out_free_temp_buffer: + ring_buffer_free(temp_buffer); out_free_cpumask: - free_cpumask_var(tracing_reader_cpumask); -out_free_tracing_cpumask: - free_cpumask_var(tracing_cpumask); + free_cpumask_var(global_trace.tracing_cpumask); out_free_buffer_mask: free_cpumask_var(tracing_buffer_mask); out: diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 3548ae5cc78..9258f5a815d 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -1,19 +1,24 @@ + #ifndef _LINUX_KERNEL_TRACE_H #define _LINUX_KERNEL_TRACE_H #include <linux/fs.h> -#include <asm/atomic.h> +#include <linux/atomic.h> #include <linux/sched.h> #include <linux/clocksource.h> #include <linux/ring_buffer.h> #include <linux/mmiotrace.h> +#include <linux/tracepoint.h> #include <linux/ftrace.h> -#include <trace/boot.h> -#include <linux/kmemtrace.h> -#include <trace/power.h> - +#include <linux/hw_breakpoint.h> #include <linux/trace_seq.h> #include <linux/ftrace_event.h> +#include <linux/compiler.h> + +#ifdef CONFIG_FTRACE_SYSCALLS +#include <asm/unistd.h> /* For NR_SYSCALLS */ +#include <asm/syscall.h> /* some archs define it here */ +#endif enum trace_type { __TRACE_FIRST_TYPE = 0, @@ -24,177 +29,65 @@ enum trace_type { TRACE_STACK, TRACE_PRINT, TRACE_BPRINT, - TRACE_SPECIAL, TRACE_MMIO_RW, TRACE_MMIO_MAP, TRACE_BRANCH, - TRACE_BOOT_CALL, - TRACE_BOOT_RET, TRACE_GRAPH_RET, TRACE_GRAPH_ENT, TRACE_USER_STACK, - TRACE_HW_BRANCHES, - TRACE_SYSCALL_ENTER, - TRACE_SYSCALL_EXIT, - TRACE_KMEM_ALLOC, - TRACE_KMEM_FREE, - TRACE_POWER, TRACE_BLK, + TRACE_BPUTS, __TRACE_LAST_TYPE, }; -/* - * Function trace entry - function address and parent function addres: - */ -struct ftrace_entry { - struct trace_entry ent; - unsigned long ip; - unsigned long parent_ip; -}; - -/* Function call entry */ -struct ftrace_graph_ent_entry { - struct trace_entry ent; - struct ftrace_graph_ent graph_ent; -}; - -/* Function return entry */ -struct ftrace_graph_ret_entry { - struct trace_entry ent; - struct ftrace_graph_ret ret; -}; -extern struct tracer boot_tracer; - -/* - * Context switch trace entry - which task (and prio) we switched from/to: - */ -struct ctx_switch_entry { - struct trace_entry ent; - unsigned int prev_pid; - unsigned char prev_prio; - unsigned char prev_state; - unsigned int next_pid; - unsigned char next_prio; - unsigned char next_state; - unsigned int next_cpu; -}; - -/* - * Special (free-form) trace entry: - */ -struct special_entry { - struct trace_entry ent; - unsigned long arg1; - unsigned long arg2; - unsigned long arg3; -}; - -/* - * Stack-trace entry: - */ - -#define FTRACE_STACK_ENTRIES 8 - -struct stack_entry { - struct trace_entry ent; - unsigned long caller[FTRACE_STACK_ENTRIES]; -}; - -struct userstack_entry { - struct trace_entry ent; - unsigned long caller[FTRACE_STACK_ENTRIES]; -}; - -/* - * trace_printk entry: - */ -struct bprint_entry { - struct trace_entry ent; - unsigned long ip; - const char *fmt; - u32 buf[]; -}; - -struct print_entry { - struct trace_entry ent; - unsigned long ip; - char buf[]; -}; -#define TRACE_OLD_SIZE 88 +#undef __field +#define __field(type, item) type item; -struct trace_field_cont { - unsigned char type; - /* Temporary till we get rid of this completely */ - char buf[TRACE_OLD_SIZE - 1]; -}; +#undef __field_struct +#define __field_struct(type, item) __field(type, item) -struct trace_mmiotrace_rw { - struct trace_entry ent; - struct mmiotrace_rw rw; -}; +#undef __field_desc +#define __field_desc(type, container, item) -struct trace_mmiotrace_map { - struct trace_entry ent; - struct mmiotrace_map map; -}; +#undef __array +#define __array(type, item, size) type item[size]; -struct trace_boot_call { - struct trace_entry ent; - struct boot_trace_call boot_call; -}; +#undef __array_desc +#define __array_desc(type, container, item, size) -struct trace_boot_ret { - struct trace_entry ent; - struct boot_trace_ret boot_ret; -}; +#undef __dynamic_array +#define __dynamic_array(type, item) type item[]; -#define TRACE_FUNC_SIZE 30 -#define TRACE_FILE_SIZE 20 -struct trace_branch { - struct trace_entry ent; - unsigned line; - char func[TRACE_FUNC_SIZE+1]; - char file[TRACE_FILE_SIZE+1]; - char correct; -}; +#undef F_STRUCT +#define F_STRUCT(args...) args -struct hw_branch_entry { - struct trace_entry ent; - u64 from; - u64 to; -}; +#undef FTRACE_ENTRY +#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \ + struct struct_name { \ + struct trace_entry ent; \ + tstruct \ + } -struct trace_power { - struct trace_entry ent; - struct power_trace state_data; -}; +#undef TP_ARGS +#define TP_ARGS(args...) args -enum kmemtrace_type_id { - KMEMTRACE_TYPE_KMALLOC = 0, /* kmalloc() or kfree(). */ - KMEMTRACE_TYPE_CACHE, /* kmem_cache_*(). */ - KMEMTRACE_TYPE_PAGES, /* __get_free_pages() and friends. */ -}; +#undef FTRACE_ENTRY_DUP +#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter) -struct kmemtrace_alloc_entry { - struct trace_entry ent; - enum kmemtrace_type_id type_id; - unsigned long call_site; - const void *ptr; - size_t bytes_req; - size_t bytes_alloc; - gfp_t gfp_flags; - int node; -}; +#undef FTRACE_ENTRY_REG +#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \ + filter, regfn) \ + FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \ + filter) -struct kmemtrace_free_entry { - struct trace_entry ent; - enum kmemtrace_type_id type_id; - unsigned long call_site; - const void *ptr; -}; +#include "trace_entries.h" +/* + * syscalls are special, and need special handling, this is why + * they are not included in trace_entries.h + */ struct syscall_trace_enter { struct trace_entry ent; int nr; @@ -204,16 +97,26 @@ struct syscall_trace_enter { struct syscall_trace_exit { struct trace_entry ent; int nr; - unsigned long ret; + long ret; }; +struct kprobe_trace_entry_head { + struct trace_entry ent; + unsigned long ip; +}; + +struct kretprobe_trace_entry_head { + struct trace_entry ent; + unsigned long func; + unsigned long ret_ip; +}; /* * trace_flag_type is an enumeration that holds different * states when a trace occurs. These are: * IRQS_OFF - interrupts were disabled * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags - * NEED_RESCED - reschedule is requested + * NEED_RESCHED - reschedule is requested * HARDIRQ - inside an interrupt handler * SOFTIRQ - inside a softirq handler */ @@ -223,10 +126,13 @@ enum trace_flag_type { TRACE_FLAG_NEED_RESCHED = 0x04, TRACE_FLAG_HARDIRQ = 0x08, TRACE_FLAG_SOFTIRQ = 0x10, + TRACE_FLAG_PREEMPT_RESCHED = 0x20, }; #define TRACE_BUF_SIZE 1024 +struct trace_array; + /* * The CPU trace array - it consists of thousands of trace entries * plus some other descriptor data: (for example which task started @@ -236,9 +142,7 @@ struct trace_array_cpu { atomic_t disabled; void *buffer_page; /* ring buffer spare */ - /* these fields get copied into max-trace: */ - unsigned long trace_idx; - unsigned long overrun; + unsigned long entries; unsigned long saved_latency; unsigned long critical_start; unsigned long critical_end; @@ -246,26 +150,117 @@ struct trace_array_cpu { unsigned long nice; unsigned long policy; unsigned long rt_priority; + unsigned long skipped_entries; cycle_t preempt_timestamp; pid_t pid; - uid_t uid; + kuid_t uid; char comm[TASK_COMM_LEN]; }; +struct tracer; + +struct trace_buffer { + struct trace_array *tr; + struct ring_buffer *buffer; + struct trace_array_cpu __percpu *data; + cycle_t time_start; + int cpu; +}; + /* * The trace array - an array of per-CPU trace arrays. This is the * highest level data structure that individual tracers deal with. * They have on/off state as well: */ struct trace_array { - struct ring_buffer *buffer; - unsigned long entries; - int cpu; - cycle_t time_start; - struct task_struct *waiter; - struct trace_array_cpu *data[NR_CPUS]; + struct list_head list; + char *name; + struct trace_buffer trace_buffer; +#ifdef CONFIG_TRACER_MAX_TRACE + /* + * The max_buffer is used to snapshot the trace when a maximum + * latency is reached, or when the user initiates a snapshot. + * Some tracers will use this to store a maximum trace while + * it continues examining live traces. + * + * The buffers for the max_buffer are set up the same as the trace_buffer + * When a snapshot is taken, the buffer of the max_buffer is swapped + * with the buffer of the trace_buffer and the buffers are reset for + * the trace_buffer so the tracing can continue. + */ + struct trace_buffer max_buffer; + bool allocated_snapshot; + unsigned long max_latency; +#endif + /* + * max_lock is used to protect the swapping of buffers + * when taking a max snapshot. The buffers themselves are + * protected by per_cpu spinlocks. But the action of the swap + * needs its own lock. + * + * This is defined as a arch_spinlock_t in order to help + * with performance when lockdep debugging is enabled. + * + * It is also used in other places outside the update_max_tr + * so it needs to be defined outside of the + * CONFIG_TRACER_MAX_TRACE. + */ + arch_spinlock_t max_lock; + int buffer_disabled; +#ifdef CONFIG_FTRACE_SYSCALLS + int sys_refcount_enter; + int sys_refcount_exit; + struct ftrace_event_file __rcu *enter_syscall_files[NR_syscalls]; + struct ftrace_event_file __rcu *exit_syscall_files[NR_syscalls]; +#endif + int stop_count; + int clock_id; + struct tracer *current_trace; + unsigned int flags; + raw_spinlock_t start_lock; + struct dentry *dir; + struct dentry *options; + struct dentry *percpu_dir; + struct dentry *event_dir; + struct list_head systems; + struct list_head events; + cpumask_var_t tracing_cpumask; /* only trace on set CPUs */ + int ref; +#ifdef CONFIG_FUNCTION_TRACER + struct ftrace_ops *ops; + /* function tracing enabled */ + int function_enabled; +#endif }; +enum { + TRACE_ARRAY_FL_GLOBAL = (1 << 0) +}; + +extern struct list_head ftrace_trace_arrays; + +extern struct mutex trace_types_lock; + +extern int trace_array_get(struct trace_array *tr); +extern void trace_array_put(struct trace_array *tr); + +/* + * The global tracer (top) should be the first trace array added, + * but we check the flag anyway. + */ +static inline struct trace_array *top_trace_array(void) +{ + struct trace_array *tr; + + if (list_empty(&ftrace_trace_arrays)) + return NULL; + + tr = list_entry(ftrace_trace_arrays.prev, + typeof(*tr), list); + WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); + return tr; +} + #define FTRACE_CMP_TYPE(var, type) \ __builtin_types_compatible_p(typeof(var), type *) @@ -301,28 +296,16 @@ extern void __ftrace_bad_type(void); IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\ IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \ IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \ - IF_ASSIGN(var, ent, struct special_entry, 0); \ + IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \ IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \ TRACE_MMIO_RW); \ IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \ TRACE_MMIO_MAP); \ - IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\ - IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\ IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \ IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \ TRACE_GRAPH_ENT); \ IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \ TRACE_GRAPH_RET); \ - IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\ - IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \ - IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry, \ - TRACE_KMEM_ALLOC); \ - IF_ASSIGN(var, ent, struct kmemtrace_free_entry, \ - TRACE_KMEM_FREE); \ - IF_ASSIGN(var, ent, struct syscall_trace_enter, \ - TRACE_SYSCALL_ENTER); \ - IF_ASSIGN(var, ent, struct syscall_trace_exit, \ - TRACE_SYSCALL_EXIT); \ __ftrace_bad_type(); \ } while (0) @@ -358,8 +341,8 @@ struct tracer_flags { * @stop: called when tracing is paused (echo 0 > tracing_enabled) * @open: called when the trace file is opened * @pipe_open: called when the trace_pipe file is opened - * @wait_pipe: override how the user waits for traces on trace_pipe * @close: called when the trace file is released + * @pipe_close: called when the trace_pipe file is released * @read: override the default read callback on trace_pipe * @splice_read: override the default splice_read callback on trace_pipe * @selftest: selftest to run on boot (see trace_selftest.c) @@ -376,8 +359,8 @@ struct tracer { void (*stop)(struct trace_array *tr); void (*open)(struct trace_iterator *iter); void (*pipe_open)(struct trace_iterator *iter); - void (*wait_pipe)(struct trace_iterator *iter); void (*close)(struct trace_iterator *iter); + void (*pipe_close)(struct trace_iterator *iter); ssize_t (*read)(struct trace_iterator *iter, struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos); @@ -394,43 +377,178 @@ struct tracer { void (*print_header)(struct seq_file *m); enum print_line_t (*print_line)(struct trace_iterator *iter); /* If you handled the flag setting, return 0 */ - int (*set_flag)(u32 old_flags, u32 bit, int set); + int (*set_flag)(struct trace_array *tr, + u32 old_flags, u32 bit, int set); + /* Return 0 if OK with change, else return non-zero */ + int (*flag_changed)(struct trace_array *tr, + u32 mask, int set); struct tracer *next; - int print_max; struct tracer_flags *flags; - struct tracer_stat *stats; + int enabled; + bool print_max; + bool allow_instances; +#ifdef CONFIG_TRACER_MAX_TRACE + bool use_max_tr; +#endif +}; + + +/* Only current can touch trace_recursion */ + +/* + * For function tracing recursion: + * The order of these bits are important. + * + * When function tracing occurs, the following steps are made: + * If arch does not support a ftrace feature: + * call internal function (uses INTERNAL bits) which calls... + * If callback is registered to the "global" list, the list + * function is called and recursion checks the GLOBAL bits. + * then this function calls... + * The function callback, which can use the FTRACE bits to + * check for recursion. + * + * Now if the arch does not suppport a feature, and it calls + * the global list function which calls the ftrace callback + * all three of these steps will do a recursion protection. + * There's no reason to do one if the previous caller already + * did. The recursion that we are protecting against will + * go through the same steps again. + * + * To prevent the multiple recursion checks, if a recursion + * bit is set that is higher than the MAX bit of the current + * check, then we know that the check was made by the previous + * caller, and we can skip the current check. + */ +enum { + TRACE_BUFFER_BIT, + TRACE_BUFFER_NMI_BIT, + TRACE_BUFFER_IRQ_BIT, + TRACE_BUFFER_SIRQ_BIT, + + /* Start of function recursion bits */ + TRACE_FTRACE_BIT, + TRACE_FTRACE_NMI_BIT, + TRACE_FTRACE_IRQ_BIT, + TRACE_FTRACE_SIRQ_BIT, + + /* INTERNAL_BITs must be greater than FTRACE_BITs */ + TRACE_INTERNAL_BIT, + TRACE_INTERNAL_NMI_BIT, + TRACE_INTERNAL_IRQ_BIT, + TRACE_INTERNAL_SIRQ_BIT, + + TRACE_CONTROL_BIT, + +/* + * Abuse of the trace_recursion. + * As we need a way to maintain state if we are tracing the function + * graph in irq because we want to trace a particular function that + * was called in irq context but we have irq tracing off. Since this + * can only be modified by current, we can reuse trace_recursion. + */ + TRACE_IRQ_BIT, }; +#define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0) +#define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0) +#define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit))) + +#define TRACE_CONTEXT_BITS 4 + +#define TRACE_FTRACE_START TRACE_FTRACE_BIT +#define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1) + +#define TRACE_LIST_START TRACE_INTERNAL_BIT +#define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1) + +#define TRACE_CONTEXT_MASK TRACE_LIST_MAX + +static __always_inline int trace_get_context_bit(void) +{ + int bit; + + if (in_interrupt()) { + if (in_nmi()) + bit = 0; -#define TRACE_PIPE_ALL_CPU -1 + else if (in_irq()) + bit = 1; + else + bit = 2; + } else + bit = 3; + + return bit; +} + +static __always_inline int trace_test_and_set_recursion(int start, int max) +{ + unsigned int val = current->trace_recursion; + int bit; + + /* A previous recursion check was made */ + if ((val & TRACE_CONTEXT_MASK) > max) + return 0; + + bit = trace_get_context_bit() + start; + if (unlikely(val & (1 << bit))) + return -1; + + val |= 1 << bit; + current->trace_recursion = val; + barrier(); + + return bit; +} + +static __always_inline void trace_clear_recursion(int bit) +{ + unsigned int val = current->trace_recursion; + + if (!bit) + return; + + bit = 1 << bit; + val &= ~bit; + + barrier(); + current->trace_recursion = val; +} + +static inline struct ring_buffer_iter * +trace_buffer_iter(struct trace_iterator *iter, int cpu) +{ + if (iter->buffer_iter && iter->buffer_iter[cpu]) + return iter->buffer_iter[cpu]; + return NULL; +} int tracer_init(struct tracer *t, struct trace_array *tr); int tracing_is_enabled(void); -void trace_wake_up(void); -void tracing_reset(struct trace_array *tr, int cpu); -void tracing_reset_online_cpus(struct trace_array *tr); +void tracing_reset(struct trace_buffer *buf, int cpu); +void tracing_reset_online_cpus(struct trace_buffer *buf); void tracing_reset_current(int cpu); -void tracing_reset_current_online_cpus(void); +void tracing_reset_all_online_cpus(void); int tracing_open_generic(struct inode *inode, struct file *filp); +bool tracing_is_disabled(void); struct dentry *trace_create_file(const char *name, - mode_t mode, + umode_t mode, struct dentry *parent, void *data, const struct file_operations *fops); +struct dentry *tracing_init_dentry_tr(struct trace_array *tr); struct dentry *tracing_init_dentry(void); -void init_tracer_sysprof_debugfs(struct dentry *d_tracer); struct ring_buffer_event; -struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr, - int type, - unsigned long len, - unsigned long flags, - int pc); -void trace_buffer_unlock_commit(struct trace_array *tr, - struct ring_buffer_event *event, - unsigned long flags, int pc); +struct ring_buffer_event * +trace_buffer_lock_reserve(struct ring_buffer *buffer, + int type, + unsigned long len, + unsigned long flags, + int pc); struct trace_entry *tracing_get_trace_entry(struct trace_array *tr, struct trace_array_cpu *data); @@ -438,18 +556,17 @@ struct trace_entry *tracing_get_trace_entry(struct trace_array *tr, struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts); -void tracing_generic_entry_update(struct trace_entry *entry, - unsigned long flags, - int pc); +void __buffer_unlock_commit(struct ring_buffer *buffer, + struct ring_buffer_event *event); + +int trace_empty(struct trace_iterator *iter); + +void *trace_find_next_entry_inc(struct trace_iterator *iter); -void default_wait_pipe(struct trace_iterator *iter); -void poll_wait_pipe(struct trace_iterator *iter); +void trace_init_global_iter(struct trace_iterator *iter); + +void tracing_iter_reset(struct trace_iterator *iter, int cpu); -void ftrace(struct trace_array *tr, - struct trace_array_cpu *data, - unsigned long ip, - unsigned long parent_ip, - unsigned long flags, int pc); void tracing_sched_switch_trace(struct trace_array *tr, struct task_struct *prev, struct task_struct *next, @@ -459,18 +576,22 @@ void tracing_sched_wakeup_trace(struct trace_array *tr, struct task_struct *wakee, struct task_struct *cur, unsigned long flags, int pc); -void trace_special(struct trace_array *tr, - struct trace_array_cpu *data, - unsigned long arg1, - unsigned long arg2, - unsigned long arg3, int pc); void trace_function(struct trace_array *tr, unsigned long ip, unsigned long parent_ip, unsigned long flags, int pc); +void trace_graph_function(struct trace_array *tr, + unsigned long ip, + unsigned long parent_ip, + unsigned long flags, int pc); +void trace_latency_header(struct seq_file *m); +void trace_default_header(struct seq_file *m); +void print_trace_header(struct seq_file *m, struct trace_iterator *iter); +int trace_empty(struct trace_iterator *iter); void trace_graph_return(struct ftrace_graph_ret *trace); int trace_graph_entry(struct ftrace_graph_ent *trace); +void set_graph_array(struct trace_array *tr); void tracing_start_cmdline_record(void); void tracing_stop_cmdline_record(void); @@ -478,44 +599,75 @@ void tracing_sched_switch_assign_trace(struct trace_array *tr); void tracing_stop_sched_switch_record(void); void tracing_start_sched_switch_record(void); int register_tracer(struct tracer *type); -void unregister_tracer(struct tracer *type); +int is_tracing_stopped(void); + +loff_t tracing_lseek(struct file *file, loff_t offset, int whence); + +extern cpumask_var_t __read_mostly tracing_buffer_mask; + +#define for_each_tracing_cpu(cpu) \ + for_each_cpu(cpu, tracing_buffer_mask) extern unsigned long nsecs_to_usecs(unsigned long nsecs); -extern unsigned long tracing_max_latency; extern unsigned long tracing_thresh; +#ifdef CONFIG_TRACER_MAX_TRACE void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu); void update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu); +#endif /* CONFIG_TRACER_MAX_TRACE */ -void __trace_stack(struct trace_array *tr, - unsigned long flags, - int skip, int pc); +#ifdef CONFIG_STACKTRACE +void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, + int skip, int pc); -extern cycle_t ftrace_now(int cpu); +void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, + int skip, int pc, struct pt_regs *regs); -#ifdef CONFIG_CONTEXT_SWITCH_TRACER -typedef void -(*tracer_switch_func_t)(void *private, - void *__rq, - struct task_struct *prev, - struct task_struct *next); - -struct tracer_switch_ops { - tracer_switch_func_t func; - void *private; - struct tracer_switch_ops *next; -}; -#endif /* CONFIG_CONTEXT_SWITCH_TRACER */ +void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, + int pc); + +void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, + int pc); +#else +static inline void ftrace_trace_stack(struct ring_buffer *buffer, + unsigned long flags, int skip, int pc) +{ +} + +static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer, + unsigned long flags, int skip, + int pc, struct pt_regs *regs) +{ +} + +static inline void ftrace_trace_userstack(struct ring_buffer *buffer, + unsigned long flags, int pc) +{ +} + +static inline void __trace_stack(struct trace_array *tr, unsigned long flags, + int skip, int pc) +{ +} +#endif /* CONFIG_STACKTRACE */ + +extern cycle_t ftrace_now(int cpu); extern void trace_find_cmdline(int pid, char comm[]); #ifdef CONFIG_DYNAMIC_FTRACE extern unsigned long ftrace_update_tot_cnt; +#endif #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func extern int DYN_FTRACE_TEST_NAME(void); -#endif +#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2 +extern int DYN_FTRACE_TEST_NAME2(void); + +extern bool ring_buffer_expanded; +extern bool tracing_selftest_disabled; +DECLARE_PER_CPU(int, ftrace_cpu_disabled); #ifdef CONFIG_FTRACE_STARTUP_TEST extern int trace_selftest_startup_function(struct tracer *trace, @@ -534,12 +686,17 @@ extern int trace_selftest_startup_nop(struct tracer *trace, struct trace_array *tr); extern int trace_selftest_startup_sched_switch(struct tracer *trace, struct trace_array *tr); -extern int trace_selftest_startup_sysprof(struct tracer *trace, - struct trace_array *tr); extern int trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr); -extern int trace_selftest_startup_hw_branches(struct tracer *trace, - struct trace_array *tr); +/* + * Tracer data references selftest functions that only occur + * on boot up. These can be __init functions. Thus, when selftests + * are enabled, then the tracers need to reference __init functions. + */ +#define __tracer_data __refdata +#else +/* Tracers are seldom changed. Optimize when selftests are disabled. */ +#define __tracer_data __read_mostly #endif /* CONFIG_FTRACE_STARTUP_TEST */ extern void *head_page(struct trace_array_cpu *data); @@ -548,69 +705,202 @@ extern int trace_vbprintk(unsigned long ip, const char *fmt, va_list args); extern int trace_vprintk(unsigned long ip, const char *fmt, va_list args); +extern int +trace_array_vprintk(struct trace_array *tr, + unsigned long ip, const char *fmt, va_list args); +int trace_array_printk(struct trace_array *tr, + unsigned long ip, const char *fmt, ...); +int trace_array_printk_buf(struct ring_buffer *buffer, + unsigned long ip, const char *fmt, ...); +void trace_printk_seq(struct trace_seq *s); +enum print_line_t print_trace_line(struct trace_iterator *iter); extern unsigned long trace_flags; /* Standard output formatting function used for function return traces */ #ifdef CONFIG_FUNCTION_GRAPH_TRACER -extern enum print_line_t print_graph_function(struct trace_iterator *iter); + +/* Flag options */ +#define TRACE_GRAPH_PRINT_OVERRUN 0x1 +#define TRACE_GRAPH_PRINT_CPU 0x2 +#define TRACE_GRAPH_PRINT_OVERHEAD 0x4 +#define TRACE_GRAPH_PRINT_PROC 0x8 +#define TRACE_GRAPH_PRINT_DURATION 0x10 +#define TRACE_GRAPH_PRINT_ABS_TIME 0x20 +#define TRACE_GRAPH_PRINT_IRQS 0x40 +#define TRACE_GRAPH_PRINT_TAIL 0x80 +#define TRACE_GRAPH_PRINT_FILL_SHIFT 28 +#define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT) + +extern enum print_line_t +print_graph_function_flags(struct trace_iterator *iter, u32 flags); +extern void print_graph_headers_flags(struct seq_file *s, u32 flags); extern enum print_line_t trace_print_graph_duration(unsigned long long duration, struct trace_seq *s); +extern void graph_trace_open(struct trace_iterator *iter); +extern void graph_trace_close(struct trace_iterator *iter); +extern int __trace_graph_entry(struct trace_array *tr, + struct ftrace_graph_ent *trace, + unsigned long flags, int pc); +extern void __trace_graph_return(struct trace_array *tr, + struct ftrace_graph_ret *trace, + unsigned long flags, int pc); + #ifdef CONFIG_DYNAMIC_FTRACE /* TODO: make this variable */ #define FTRACE_GRAPH_MAX_FUNCS 32 extern int ftrace_graph_count; extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS]; +extern int ftrace_graph_notrace_count; +extern unsigned long ftrace_graph_notrace_funcs[FTRACE_GRAPH_MAX_FUNCS]; static inline int ftrace_graph_addr(unsigned long addr) { int i; - if (!ftrace_graph_count || test_tsk_trace_graph(current)) + if (!ftrace_graph_count) return 1; for (i = 0; i < ftrace_graph_count; i++) { - if (addr == ftrace_graph_funcs[i]) + if (addr == ftrace_graph_funcs[i]) { + /* + * If no irqs are to be traced, but a set_graph_function + * is set, and called by an interrupt handler, we still + * want to trace it. + */ + if (in_irq()) + trace_recursion_set(TRACE_IRQ_BIT); + else + trace_recursion_clear(TRACE_IRQ_BIT); return 1; + } } return 0; } -#else -static inline int ftrace_trace_addr(unsigned long addr) + +static inline int ftrace_graph_notrace_addr(unsigned long addr) { - return 1; + int i; + + if (!ftrace_graph_notrace_count) + return 0; + + for (i = 0; i < ftrace_graph_notrace_count; i++) { + if (addr == ftrace_graph_notrace_funcs[i]) + return 1; + } + + return 0; } +#else static inline int ftrace_graph_addr(unsigned long addr) { return 1; } + +static inline int ftrace_graph_notrace_addr(unsigned long addr) +{ + return 0; +} #endif /* CONFIG_DYNAMIC_FTRACE */ #else /* CONFIG_FUNCTION_GRAPH_TRACER */ static inline enum print_line_t -print_graph_function(struct trace_iterator *iter) +print_graph_function_flags(struct trace_iterator *iter, u32 flags) { return TRACE_TYPE_UNHANDLED; } #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ -extern struct pid *ftrace_pid_trace; +extern struct list_head ftrace_pids; #ifdef CONFIG_FUNCTION_TRACER +extern bool ftrace_filter_param __initdata; static inline int ftrace_trace_task(struct task_struct *task) { - if (!ftrace_pid_trace) + if (list_empty(&ftrace_pids)) return 1; return test_tsk_trace_trace(task); } +extern int ftrace_is_dead(void); +int ftrace_create_function_files(struct trace_array *tr, + struct dentry *parent); +void ftrace_destroy_function_files(struct trace_array *tr); +void ftrace_init_global_array_ops(struct trace_array *tr); +void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func); +void ftrace_reset_array_ops(struct trace_array *tr); +int using_ftrace_ops_list_func(void); #else static inline int ftrace_trace_task(struct task_struct *task) { return 1; } -#endif +static inline int ftrace_is_dead(void) { return 0; } +static inline int +ftrace_create_function_files(struct trace_array *tr, + struct dentry *parent) +{ + return 0; +} +static inline void ftrace_destroy_function_files(struct trace_array *tr) { } +static inline __init void +ftrace_init_global_array_ops(struct trace_array *tr) { } +static inline void ftrace_reset_array_ops(struct trace_array *tr) { } +/* ftace_func_t type is not defined, use macro instead of static inline */ +#define ftrace_init_array_ops(tr, func) do { } while (0) +#endif /* CONFIG_FUNCTION_TRACER */ + +#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE) +void ftrace_create_filter_files(struct ftrace_ops *ops, + struct dentry *parent); +void ftrace_destroy_filter_files(struct ftrace_ops *ops); +#else +/* + * The ops parameter passed in is usually undefined. + * This must be a macro. + */ +#define ftrace_create_filter_files(ops, parent) do { } while (0) +#define ftrace_destroy_filter_files(ops) do { } while (0) +#endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */ + +int ftrace_event_is_function(struct ftrace_event_call *call); + +/* + * struct trace_parser - servers for reading the user input separated by spaces + * @cont: set if the input is not complete - no final space char was found + * @buffer: holds the parsed user input + * @idx: user input length + * @size: buffer size + */ +struct trace_parser { + bool cont; + char *buffer; + unsigned idx; + unsigned size; +}; + +static inline bool trace_parser_loaded(struct trace_parser *parser) +{ + return (parser->idx != 0); +} + +static inline bool trace_parser_cont(struct trace_parser *parser) +{ + return parser->cont; +} + +static inline void trace_parser_clear(struct trace_parser *parser) +{ + parser->cont = false; + parser->idx = 0; +} + +extern int trace_parser_get_init(struct trace_parser *parser, int size); +extern void trace_parser_put(struct trace_parser *parser); +extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf, + size_t cnt, loff_t *ppos); /* * trace_iterator_flags is an enumeration that defines bit @@ -629,19 +919,23 @@ enum trace_iterator_flags { TRACE_ITER_BIN = 0x40, TRACE_ITER_BLOCK = 0x80, TRACE_ITER_STACKTRACE = 0x100, - TRACE_ITER_SCHED_TREE = 0x200, - TRACE_ITER_PRINTK = 0x400, - TRACE_ITER_PREEMPTONLY = 0x800, - TRACE_ITER_BRANCH = 0x1000, - TRACE_ITER_ANNOTATE = 0x2000, - TRACE_ITER_USERSTACKTRACE = 0x4000, - TRACE_ITER_SYM_USEROBJ = 0x8000, - TRACE_ITER_PRINTK_MSGONLY = 0x10000, - TRACE_ITER_CONTEXT_INFO = 0x20000, /* Print pid/cpu/time */ - TRACE_ITER_LATENCY_FMT = 0x40000, - TRACE_ITER_GLOBAL_CLK = 0x80000, - TRACE_ITER_SLEEP_TIME = 0x100000, - TRACE_ITER_GRAPH_TIME = 0x200000, + TRACE_ITER_PRINTK = 0x200, + TRACE_ITER_PREEMPTONLY = 0x400, + TRACE_ITER_BRANCH = 0x800, + TRACE_ITER_ANNOTATE = 0x1000, + TRACE_ITER_USERSTACKTRACE = 0x2000, + TRACE_ITER_SYM_USEROBJ = 0x4000, + TRACE_ITER_PRINTK_MSGONLY = 0x8000, + TRACE_ITER_CONTEXT_INFO = 0x10000, /* Print pid/cpu/time */ + TRACE_ITER_LATENCY_FMT = 0x20000, + TRACE_ITER_SLEEP_TIME = 0x40000, + TRACE_ITER_GRAPH_TIME = 0x80000, + TRACE_ITER_RECORD_CMD = 0x100000, + TRACE_ITER_OVERWRITE = 0x200000, + TRACE_ITER_STOP_ON_FREE = 0x400000, + TRACE_ITER_IRQ_INFO = 0x800000, + TRACE_ITER_MARKERS = 0x1000000, + TRACE_ITER_FUNCTION = 0x2000000, }; /* @@ -653,54 +947,6 @@ enum trace_iterator_flags { extern struct tracer nop_trace; -/** - * ftrace_preempt_disable - disable preemption scheduler safe - * - * When tracing can happen inside the scheduler, there exists - * cases that the tracing might happen before the need_resched - * flag is checked. If this happens and the tracer calls - * preempt_enable (after a disable), a schedule might take place - * causing an infinite recursion. - * - * To prevent this, we read the need_resched flag before - * disabling preemption. When we want to enable preemption we - * check the flag, if it is set, then we call preempt_enable_no_resched. - * Otherwise, we call preempt_enable. - * - * The rational for doing the above is that if need_resched is set - * and we have yet to reschedule, we are either in an atomic location - * (where we do not need to check for scheduling) or we are inside - * the scheduler and do not want to resched. - */ -static inline int ftrace_preempt_disable(void) -{ - int resched; - - resched = need_resched(); - preempt_disable_notrace(); - - return resched; -} - -/** - * ftrace_preempt_enable - enable preemption scheduler safe - * @resched: the return value from ftrace_preempt_disable - * - * This is a scheduler safe way to enable preemption and not miss - * any preemption checks. The disabled saved the state of preemption. - * If resched is set, then we are either inside an atomic or - * are inside the scheduler (we would have already scheduled - * otherwise). In this case, we do not want to call normal - * preempt_enable, but preempt_enable_no_resched instead. - */ -static inline void ftrace_preempt_enable(int resched) -{ - if (resched) - preempt_enable_no_resched_notrace(); - else - preempt_enable_notrace(); -} - #ifdef CONFIG_BRANCH_TRACER extern int enable_branch_tracing(struct trace_array *tr); extern void disable_branch_tracing(void); @@ -728,125 +974,338 @@ static inline void trace_branch_disable(void) /* set ring buffers to default size if not already done so */ int tracing_update_buffers(void); -/* trace event type bit fields, not numeric */ -enum { - TRACE_EVENT_TYPE_PRINTF = 1, - TRACE_EVENT_TYPE_RAW = 2, -}; - struct ftrace_event_field { struct list_head link; - char *name; - char *type; + const char *name; + const char *type; + int filter_type; int offset; int size; int is_signed; }; struct event_filter { - int n_preds; - struct filter_pred **preds; + int n_preds; /* Number assigned */ + int a_preds; /* allocated */ + struct filter_pred *preds; + struct filter_pred *root; char *filter_string; }; struct event_subsystem { struct list_head list; const char *name; - struct dentry *entry; - void *filter; + struct event_filter *filter; + int ref_count; }; +struct ftrace_subsystem_dir { + struct list_head list; + struct event_subsystem *subsystem; + struct trace_array *tr; + struct dentry *entry; + int ref_count; + int nr_events; +}; + +#define FILTER_PRED_INVALID ((unsigned short)-1) +#define FILTER_PRED_IS_RIGHT (1 << 15) +#define FILTER_PRED_FOLD (1 << 15) + +/* + * The max preds is the size of unsigned short with + * two flags at the MSBs. One bit is used for both the IS_RIGHT + * and FOLD flags. The other is reserved. + * + * 2^14 preds is way more than enough. + */ +#define MAX_FILTER_PRED 16384 + struct filter_pred; +struct regex; -typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event, - int val1, int val2); +typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event); + +typedef int (*regex_match_func)(char *str, struct regex *r, int len); + +enum regex_type { + MATCH_FULL = 0, + MATCH_FRONT_ONLY, + MATCH_MIDDLE_ONLY, + MATCH_END_ONLY, +}; + +struct regex { + char pattern[MAX_FILTER_STR_VAL]; + int len; + int field_len; + regex_match_func match; +}; struct filter_pred { - filter_pred_fn_t fn; - u64 val; - char str_val[MAX_FILTER_STR_VAL]; - int str_len; - char *field_name; - int offset; - int not; - int op; - int pop_n; + filter_pred_fn_t fn; + u64 val; + struct regex regex; + unsigned short *ops; + struct ftrace_event_field *field; + int offset; + int not; + int op; + unsigned short index; + unsigned short parent; + unsigned short left; + unsigned short right; }; -extern void print_event_filter(struct ftrace_event_call *call, +extern enum regex_type +filter_parse_regex(char *buff, int len, char **search, int *not); +extern void print_event_filter(struct ftrace_event_file *file, struct trace_seq *s); -extern int apply_event_filter(struct ftrace_event_call *call, +extern int apply_event_filter(struct ftrace_event_file *file, char *filter_string); -extern int apply_subsystem_event_filter(struct event_subsystem *system, +extern int apply_subsystem_event_filter(struct ftrace_subsystem_dir *dir, char *filter_string); extern void print_subsystem_event_filter(struct event_subsystem *system, struct trace_seq *s); +extern int filter_assign_type(const char *type); +extern int create_event_filter(struct ftrace_event_call *call, + char *filter_str, bool set_str, + struct event_filter **filterp); +extern void free_event_filter(struct event_filter *filter); -static inline int -filter_check_discard(struct ftrace_event_call *call, void *rec, - struct ring_buffer *buffer, - struct ring_buffer_event *event) -{ - if (unlikely(call->filter_active) && !filter_match_preds(call, rec)) { - ring_buffer_discard_commit(buffer, event); - return 1; - } +struct ftrace_event_field * +trace_find_event_field(struct ftrace_event_call *call, char *name); - return 0; -} +extern void trace_event_enable_cmd_record(bool enable); +extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr); +extern int event_trace_del_tracer(struct trace_array *tr); -#define DEFINE_COMPARISON_PRED(type) \ -static int filter_pred_##type(struct filter_pred *pred, void *event, \ - int val1, int val2) \ -{ \ - type *addr = (type *)(event + pred->offset); \ - type val = (type)pred->val; \ - int match = 0; \ - \ - switch (pred->op) { \ - case OP_LT: \ - match = (*addr < val); \ - break; \ - case OP_LE: \ - match = (*addr <= val); \ - break; \ - case OP_GT: \ - match = (*addr > val); \ - break; \ - case OP_GE: \ - match = (*addr >= val); \ - break; \ - default: \ - break; \ - } \ - \ - return match; \ -} +extern struct ftrace_event_file *find_event_file(struct trace_array *tr, + const char *system, + const char *event); -#define DEFINE_EQUALITY_PRED(size) \ -static int filter_pred_##size(struct filter_pred *pred, void *event, \ - int val1, int val2) \ -{ \ - u##size *addr = (u##size *)(event + pred->offset); \ - u##size val = (u##size)pred->val; \ - int match; \ - \ - match = (val == *addr) ^ pred->not; \ - \ - return match; \ +static inline void *event_file_data(struct file *filp) +{ + return ACCESS_ONCE(file_inode(filp)->i_private); } extern struct mutex event_mutex; extern struct list_head ftrace_events; +extern const struct file_operations event_trigger_fops; + +extern int register_trigger_cmds(void); +extern void clear_event_triggers(struct trace_array *tr); + +struct event_trigger_data { + unsigned long count; + int ref; + struct event_trigger_ops *ops; + struct event_command *cmd_ops; + struct event_filter __rcu *filter; + char *filter_str; + void *private_data; + struct list_head list; +}; + +/** + * struct event_trigger_ops - callbacks for trace event triggers + * + * The methods in this structure provide per-event trigger hooks for + * various trigger operations. + * + * All the methods below, except for @init() and @free(), must be + * implemented. + * + * @func: The trigger 'probe' function called when the triggering + * event occurs. The data passed into this callback is the data + * that was supplied to the event_command @reg() function that + * registered the trigger (see struct event_command). + * + * @init: An optional initialization function called for the trigger + * when the trigger is registered (via the event_command reg() + * function). This can be used to perform per-trigger + * initialization such as incrementing a per-trigger reference + * count, for instance. This is usually implemented by the + * generic utility function @event_trigger_init() (see + * trace_event_triggers.c). + * + * @free: An optional de-initialization function called for the + * trigger when the trigger is unregistered (via the + * event_command @reg() function). This can be used to perform + * per-trigger de-initialization such as decrementing a + * per-trigger reference count and freeing corresponding trigger + * data, for instance. This is usually implemented by the + * generic utility function @event_trigger_free() (see + * trace_event_triggers.c). + * + * @print: The callback function invoked to have the trigger print + * itself. This is usually implemented by a wrapper function + * that calls the generic utility function @event_trigger_print() + * (see trace_event_triggers.c). + */ +struct event_trigger_ops { + void (*func)(struct event_trigger_data *data); + int (*init)(struct event_trigger_ops *ops, + struct event_trigger_data *data); + void (*free)(struct event_trigger_ops *ops, + struct event_trigger_data *data); + int (*print)(struct seq_file *m, + struct event_trigger_ops *ops, + struct event_trigger_data *data); +}; + +/** + * struct event_command - callbacks and data members for event commands + * + * Event commands are invoked by users by writing the command name + * into the 'trigger' file associated with a trace event. The + * parameters associated with a specific invocation of an event + * command are used to create an event trigger instance, which is + * added to the list of trigger instances associated with that trace + * event. When the event is hit, the set of triggers associated with + * that event is invoked. + * + * The data members in this structure provide per-event command data + * for various event commands. + * + * All the data members below, except for @post_trigger, must be set + * for each event command. + * + * @name: The unique name that identifies the event command. This is + * the name used when setting triggers via trigger files. + * + * @trigger_type: A unique id that identifies the event command + * 'type'. This value has two purposes, the first to ensure that + * only one trigger of the same type can be set at a given time + * for a particular event e.g. it doesn't make sense to have both + * a traceon and traceoff trigger attached to a single event at + * the same time, so traceon and traceoff have the same type + * though they have different names. The @trigger_type value is + * also used as a bit value for deferring the actual trigger + * action until after the current event is finished. Some + * commands need to do this if they themselves log to the trace + * buffer (see the @post_trigger() member below). @trigger_type + * values are defined by adding new values to the trigger_type + * enum in include/linux/ftrace_event.h. + * + * @post_trigger: A flag that says whether or not this command needs + * to have its action delayed until after the current event has + * been closed. Some triggers need to avoid being invoked while + * an event is currently in the process of being logged, since + * the trigger may itself log data into the trace buffer. Thus + * we make sure the current event is committed before invoking + * those triggers. To do that, the trigger invocation is split + * in two - the first part checks the filter using the current + * trace record; if a command has the @post_trigger flag set, it + * sets a bit for itself in the return value, otherwise it + * directly invokes the trigger. Once all commands have been + * either invoked or set their return flag, the current record is + * either committed or discarded. At that point, if any commands + * have deferred their triggers, those commands are finally + * invoked following the close of the current event. In other + * words, if the event_trigger_ops @func() probe implementation + * itself logs to the trace buffer, this flag should be set, + * otherwise it can be left unspecified. + * + * All the methods below, except for @set_filter(), must be + * implemented. + * + * @func: The callback function responsible for parsing and + * registering the trigger written to the 'trigger' file by the + * user. It allocates the trigger instance and registers it with + * the appropriate trace event. It makes use of the other + * event_command callback functions to orchestrate this, and is + * usually implemented by the generic utility function + * @event_trigger_callback() (see trace_event_triggers.c). + * + * @reg: Adds the trigger to the list of triggers associated with the + * event, and enables the event trigger itself, after + * initializing it (via the event_trigger_ops @init() function). + * This is also where commands can use the @trigger_type value to + * make the decision as to whether or not multiple instances of + * the trigger should be allowed. This is usually implemented by + * the generic utility function @register_trigger() (see + * trace_event_triggers.c). + * + * @unreg: Removes the trigger from the list of triggers associated + * with the event, and disables the event trigger itself, after + * initializing it (via the event_trigger_ops @free() function). + * This is usually implemented by the generic utility function + * @unregister_trigger() (see trace_event_triggers.c). + * + * @set_filter: An optional function called to parse and set a filter + * for the trigger. If no @set_filter() method is set for the + * event command, filters set by the user for the command will be + * ignored. This is usually implemented by the generic utility + * function @set_trigger_filter() (see trace_event_triggers.c). + * + * @get_trigger_ops: The callback function invoked to retrieve the + * event_trigger_ops implementation associated with the command. + */ +struct event_command { + struct list_head list; + char *name; + enum event_trigger_type trigger_type; + bool post_trigger; + int (*func)(struct event_command *cmd_ops, + struct ftrace_event_file *file, + char *glob, char *cmd, char *params); + int (*reg)(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct ftrace_event_file *file); + void (*unreg)(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct ftrace_event_file *file); + int (*set_filter)(char *filter_str, + struct event_trigger_data *data, + struct ftrace_event_file *file); + struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param); +}; + +extern int trace_event_enable_disable(struct ftrace_event_file *file, + int enable, int soft_disable); +extern int tracing_alloc_snapshot(void); + extern const char *__start___trace_bprintk_fmt[]; extern const char *__stop___trace_bprintk_fmt[]; -#undef TRACE_EVENT_FORMAT -#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \ - extern struct ftrace_event_call event_##call; -#undef TRACE_EVENT_FORMAT_NOFILTER -#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, tpfmt) -#include "trace_event_types.h" +extern const char *__start___tracepoint_str[]; +extern const char *__stop___tracepoint_str[]; + +void trace_printk_init_buffers(void); +void trace_printk_start_comm(void); +int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set); +int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled); + +/* + * Normal trace_printk() and friends allocates special buffers + * to do the manipulation, as well as saves the print formats + * into sections to display. But the trace infrastructure wants + * to use these without the added overhead at the price of being + * a bit slower (used mainly for warnings, where we don't care + * about performance). The internal_trace_puts() is for such + * a purpose. + */ +#define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str)) + +#undef FTRACE_ENTRY +#define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \ + extern struct ftrace_event_call \ + __aligned(4) event_##call; +#undef FTRACE_ENTRY_DUP +#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \ + FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \ + filter) +#include "trace_entries.h" + +#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER) +int perf_ftrace_event_register(struct ftrace_event_call *call, + enum trace_reg type, void *data); +#else +#define perf_ftrace_event_register NULL +#endif #endif /* _LINUX_KERNEL_TRACE_H */ diff --git a/kernel/trace/trace_benchmark.c b/kernel/trace/trace_benchmark.c new file mode 100644 index 00000000000..40a14cbcf8e --- /dev/null +++ b/kernel/trace/trace_benchmark.c @@ -0,0 +1,198 @@ +#include <linux/delay.h> +#include <linux/module.h> +#include <linux/kthread.h> +#include <linux/trace_clock.h> + +#define CREATE_TRACE_POINTS +#include "trace_benchmark.h" + +static struct task_struct *bm_event_thread; + +static char bm_str[BENCHMARK_EVENT_STRLEN] = "START"; + +static u64 bm_total; +static u64 bm_totalsq; +static u64 bm_last; +static u64 bm_max; +static u64 bm_min; +static u64 bm_first; +static u64 bm_cnt; +static u64 bm_stddev; +static unsigned int bm_avg; +static unsigned int bm_std; + +/* + * This gets called in a loop recording the time it took to write + * the tracepoint. What it writes is the time statistics of the last + * tracepoint write. As there is nothing to write the first time + * it simply writes "START". As the first write is cold cache and + * the rest is hot, we save off that time in bm_first and it is + * reported as "first", which is shown in the second write to the + * tracepoint. The "first" field is writen within the statics from + * then on but never changes. + */ +static void trace_do_benchmark(void) +{ + u64 start; + u64 stop; + u64 delta; + u64 stddev; + u64 seed; + u64 last_seed; + unsigned int avg; + unsigned int std = 0; + + /* Only run if the tracepoint is actually active */ + if (!trace_benchmark_event_enabled()) + return; + + local_irq_disable(); + start = trace_clock_local(); + trace_benchmark_event(bm_str); + stop = trace_clock_local(); + local_irq_enable(); + + bm_cnt++; + + delta = stop - start; + + /* + * The first read is cold cached, keep it separate from the + * other calculations. + */ + if (bm_cnt == 1) { + bm_first = delta; + scnprintf(bm_str, BENCHMARK_EVENT_STRLEN, + "first=%llu [COLD CACHED]", bm_first); + return; + } + + bm_last = delta; + + if (delta > bm_max) + bm_max = delta; + if (!bm_min || delta < bm_min) + bm_min = delta; + + /* + * When bm_cnt is greater than UINT_MAX, it breaks the statistics + * accounting. Freeze the statistics when that happens. + * We should have enough data for the avg and stddev anyway. + */ + if (bm_cnt > UINT_MAX) { + scnprintf(bm_str, BENCHMARK_EVENT_STRLEN, + "last=%llu first=%llu max=%llu min=%llu ** avg=%u std=%d std^2=%lld", + bm_last, bm_first, bm_max, bm_min, bm_avg, bm_std, bm_stddev); + return; + } + + bm_total += delta; + bm_totalsq += delta * delta; + + + if (bm_cnt > 1) { + /* + * Apply Welford's method to calculate standard deviation: + * s^2 = 1 / (n * (n-1)) * (n * \Sum (x_i)^2 - (\Sum x_i)^2) + */ + stddev = (u64)bm_cnt * bm_totalsq - bm_total * bm_total; + do_div(stddev, (u32)bm_cnt); + do_div(stddev, (u32)bm_cnt - 1); + } else + stddev = 0; + + delta = bm_total; + do_div(delta, bm_cnt); + avg = delta; + + if (stddev > 0) { + int i = 0; + /* + * stddev is the square of standard deviation but + * we want the actualy number. Use the average + * as our seed to find the std. + * + * The next try is: + * x = (x + N/x) / 2 + * + * Where N is the squared number to find the square + * root of. + */ + seed = avg; + do { + last_seed = seed; + seed = stddev; + if (!last_seed) + break; + do_div(seed, last_seed); + seed += last_seed; + do_div(seed, 2); + } while (i++ < 10 && last_seed != seed); + + std = seed; + } + + scnprintf(bm_str, BENCHMARK_EVENT_STRLEN, + "last=%llu first=%llu max=%llu min=%llu avg=%u std=%d std^2=%lld", + bm_last, bm_first, bm_max, bm_min, avg, std, stddev); + + bm_std = std; + bm_avg = avg; + bm_stddev = stddev; +} + +static int benchmark_event_kthread(void *arg) +{ + /* sleep a bit to make sure the tracepoint gets activated */ + msleep(100); + + while (!kthread_should_stop()) { + + trace_do_benchmark(); + + /* + * We don't go to sleep, but let others + * run as well. + */ + cond_resched(); + } + + return 0; +} + +/* + * When the benchmark tracepoint is enabled, it calls this + * function and the thread that calls the tracepoint is created. + */ +void trace_benchmark_reg(void) +{ + bm_event_thread = kthread_run(benchmark_event_kthread, + NULL, "event_benchmark"); + WARN_ON(!bm_event_thread); +} + +/* + * When the benchmark tracepoint is disabled, it calls this + * function and the thread that calls the tracepoint is deleted + * and all the numbers are reset. + */ +void trace_benchmark_unreg(void) +{ + if (!bm_event_thread) + return; + + kthread_stop(bm_event_thread); + + strcpy(bm_str, "START"); + bm_total = 0; + bm_totalsq = 0; + bm_last = 0; + bm_max = 0; + bm_min = 0; + bm_cnt = 0; + /* These don't need to be reset but reset them anyway */ + bm_first = 0; + bm_std = 0; + bm_avg = 0; + bm_stddev = 0; +} diff --git a/kernel/trace/trace_benchmark.h b/kernel/trace/trace_benchmark.h new file mode 100644 index 00000000000..3c1df1df4e2 --- /dev/null +++ b/kernel/trace/trace_benchmark.h @@ -0,0 +1,41 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM benchmark + +#if !defined(_TRACE_BENCHMARK_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_BENCHMARK_H + +#include <linux/tracepoint.h> + +extern void trace_benchmark_reg(void); +extern void trace_benchmark_unreg(void); + +#define BENCHMARK_EVENT_STRLEN 128 + +TRACE_EVENT_FN(benchmark_event, + + TP_PROTO(const char *str), + + TP_ARGS(str), + + TP_STRUCT__entry( + __array( char, str, BENCHMARK_EVENT_STRLEN ) + ), + + TP_fast_assign( + memcpy(__entry->str, str, BENCHMARK_EVENT_STRLEN); + ), + + TP_printk("%s", __entry->str), + + trace_benchmark_reg, trace_benchmark_unreg +); + +#endif /* _TRACE_BENCHMARK_H */ + +#undef TRACE_INCLUDE_FILE +#undef TRACE_INCLUDE_PATH +#define TRACE_INCLUDE_PATH . +#define TRACE_INCLUDE_FILE trace_benchmark + +/* This part must be outside protection */ +#include <trace/define_trace.h> diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c deleted file mode 100644 index a29ef23ffb4..00000000000 --- a/kernel/trace/trace_boot.c +++ /dev/null @@ -1,179 +0,0 @@ -/* - * ring buffer based initcalls tracer - * - * Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com> - * - */ - -#include <linux/init.h> -#include <linux/debugfs.h> -#include <linux/ftrace.h> -#include <linux/kallsyms.h> -#include <linux/time.h> - -#include "trace.h" -#include "trace_output.h" - -static struct trace_array *boot_trace; -static bool pre_initcalls_finished; - -/* Tells the boot tracer that the pre_smp_initcalls are finished. - * So we are ready . - * It doesn't enable sched events tracing however. - * You have to call enable_boot_trace to do so. - */ -void start_boot_trace(void) -{ - pre_initcalls_finished = true; -} - -void enable_boot_trace(void) -{ - if (boot_trace && pre_initcalls_finished) - tracing_start_sched_switch_record(); -} - -void disable_boot_trace(void) -{ - if (boot_trace && pre_initcalls_finished) - tracing_stop_sched_switch_record(); -} - -static int boot_trace_init(struct trace_array *tr) -{ - int cpu; - boot_trace = tr; - - if (!tr) - return 0; - - for_each_cpu(cpu, cpu_possible_mask) - tracing_reset(tr, cpu); - - tracing_sched_switch_assign_trace(tr); - return 0; -} - -static enum print_line_t -initcall_call_print_line(struct trace_iterator *iter) -{ - struct trace_entry *entry = iter->ent; - struct trace_seq *s = &iter->seq; - struct trace_boot_call *field; - struct boot_trace_call *call; - u64 ts; - unsigned long nsec_rem; - int ret; - - trace_assign_type(field, entry); - call = &field->boot_call; - ts = iter->ts; - nsec_rem = do_div(ts, NSEC_PER_SEC); - - ret = trace_seq_printf(s, "[%5ld.%09ld] calling %s @ %i\n", - (unsigned long)ts, nsec_rem, call->func, call->caller); - - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - else - return TRACE_TYPE_HANDLED; -} - -static enum print_line_t -initcall_ret_print_line(struct trace_iterator *iter) -{ - struct trace_entry *entry = iter->ent; - struct trace_seq *s = &iter->seq; - struct trace_boot_ret *field; - struct boot_trace_ret *init_ret; - u64 ts; - unsigned long nsec_rem; - int ret; - - trace_assign_type(field, entry); - init_ret = &field->boot_ret; - ts = iter->ts; - nsec_rem = do_div(ts, NSEC_PER_SEC); - - ret = trace_seq_printf(s, "[%5ld.%09ld] initcall %s " - "returned %d after %llu msecs\n", - (unsigned long) ts, - nsec_rem, - init_ret->func, init_ret->result, init_ret->duration); - - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - else - return TRACE_TYPE_HANDLED; -} - -static enum print_line_t initcall_print_line(struct trace_iterator *iter) -{ - struct trace_entry *entry = iter->ent; - - switch (entry->type) { - case TRACE_BOOT_CALL: - return initcall_call_print_line(iter); - case TRACE_BOOT_RET: - return initcall_ret_print_line(iter); - default: - return TRACE_TYPE_UNHANDLED; - } -} - -struct tracer boot_tracer __read_mostly = -{ - .name = "initcall", - .init = boot_trace_init, - .reset = tracing_reset_online_cpus, - .print_line = initcall_print_line, -}; - -void trace_boot_call(struct boot_trace_call *bt, initcall_t fn) -{ - struct ring_buffer_event *event; - struct trace_boot_call *entry; - struct trace_array *tr = boot_trace; - - if (!tr || !pre_initcalls_finished) - return; - - /* Get its name now since this function could - * disappear because it is in the .init section. - */ - sprint_symbol(bt->func, (unsigned long)fn); - preempt_disable(); - - event = trace_buffer_lock_reserve(tr, TRACE_BOOT_CALL, - sizeof(*entry), 0, 0); - if (!event) - goto out; - entry = ring_buffer_event_data(event); - entry->boot_call = *bt; - trace_buffer_unlock_commit(tr, event, 0, 0); - out: - preempt_enable(); -} - -void trace_boot_ret(struct boot_trace_ret *bt, initcall_t fn) -{ - struct ring_buffer_event *event; - struct trace_boot_ret *entry; - struct trace_array *tr = boot_trace; - - if (!tr || !pre_initcalls_finished) - return; - - sprint_symbol(bt->func, (unsigned long)fn); - preempt_disable(); - - event = trace_buffer_lock_reserve(tr, TRACE_BOOT_RET, - sizeof(*entry), 0, 0); - if (!event) - goto out; - entry = ring_buffer_event_data(event); - entry->boot_ret = *bt; - trace_buffer_unlock_commit(tr, event, 0, 0); - out: - preempt_enable(); -} diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c index 7a7a9fd249a..697fb9bac8f 100644 --- a/kernel/trace/trace_branch.c +++ b/kernel/trace/trace_branch.c @@ -32,8 +32,10 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect) { struct ftrace_event_call *call = &event_branch; struct trace_array *tr = branch_tracer; + struct trace_array_cpu *data; struct ring_buffer_event *event; struct trace_branch *entry; + struct ring_buffer *buffer; unsigned long flags; int cpu, pc; const char *p; @@ -50,11 +52,13 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect) local_irq_save(flags); cpu = raw_smp_processor_id(); - if (atomic_inc_return(&tr->data[cpu]->disabled) != 1) + data = per_cpu_ptr(tr->trace_buffer.data, cpu); + if (atomic_inc_return(&data->disabled) != 1) goto out; pc = preempt_count(); - event = trace_buffer_lock_reserve(tr, TRACE_BRANCH, + buffer = tr->trace_buffer.buffer; + event = trace_buffer_lock_reserve(buffer, TRACE_BRANCH, sizeof(*entry), flags, pc); if (!event) goto out; @@ -74,11 +78,11 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect) entry->line = f->line; entry->correct = val == expect; - if (!filter_check_discard(call, entry, tr->buffer, event)) - ring_buffer_unlock_commit(tr->buffer, event); + if (!call_filter_check_discard(call, entry, buffer, event)) + __buffer_unlock_commit(buffer, event); out: - atomic_dec(&tr->data[cpu]->disabled); + atomic_dec(&data->disabled); local_irq_restore(flags); } @@ -141,7 +145,7 @@ static void branch_trace_reset(struct trace_array *tr) } static enum print_line_t trace_branch_print(struct trace_iterator *iter, - int flags) + int flags, struct trace_event *event) { struct trace_branch *field; @@ -165,9 +169,13 @@ static void branch_print_header(struct seq_file *s) " |\n"); } +static struct trace_event_functions trace_branch_funcs = { + .trace = trace_branch_print, +}; + static struct trace_event trace_branch_event = { .type = TRACE_BRANCH, - .trace = trace_branch_print, + .funcs = &trace_branch_funcs, }; static struct tracer branch_trace __read_mostly = @@ -193,7 +201,7 @@ __init static int init_branch_tracer(void) } return register_tracer(&branch_trace); } -device_initcall(init_branch_tracer); +core_initcall(init_branch_tracer); #else static inline @@ -305,8 +313,23 @@ static int annotated_branch_stat_cmp(void *p1, void *p2) return -1; if (percent_a > percent_b) return 1; - else - return 0; + + if (a->incorrect < b->incorrect) + return -1; + if (a->incorrect > b->incorrect) + return 1; + + /* + * Since the above shows worse (incorrect) cases + * first, we continue that by showing best (correct) + * cases last. + */ + if (a->correct > b->correct) + return -1; + if (a->correct < b->correct) + return 1; + + return 0; } static struct tracer_stat annotated_branch_stats = { diff --git a/kernel/trace/trace_clock.c b/kernel/trace/trace_clock.c index b588fd81f7f..57b67b1f24d 100644 --- a/kernel/trace/trace_clock.c +++ b/kernel/trace/trace_clock.c @@ -13,6 +13,7 @@ * Tracer plugins will chose a default from these clocks. */ #include <linux/spinlock.h> +#include <linux/irqflags.h> #include <linux/hardirq.h> #include <linux/module.h> #include <linux/percpu.h> @@ -28,7 +29,6 @@ */ u64 notrace trace_clock_local(void) { - unsigned long flags; u64 clock; /* @@ -36,15 +36,16 @@ u64 notrace trace_clock_local(void) * lockless clock. It is not guaranteed to be coherent across * CPUs, nor across CPU idle events. */ - raw_local_irq_save(flags); + preempt_disable_notrace(); clock = sched_clock(); - raw_local_irq_restore(flags); + preempt_enable_notrace(); return clock; } +EXPORT_SYMBOL_GPL(trace_clock_local); /* - * trace_clock(): 'inbetween' trace clock. Not completely serialized, + * trace_clock(): 'between' trace clock. Not completely serialized, * but not completely incorrect when crossing CPUs either. * * This is based on cpu_clock(), which will allow at most ~1 jiffy of @@ -53,9 +54,20 @@ u64 notrace trace_clock_local(void) */ u64 notrace trace_clock(void) { - return cpu_clock(raw_smp_processor_id()); + return local_clock(); } +/* + * trace_jiffy_clock(): Simply use jiffies as a clock counter. + * Note that this use of jiffies_64 is not completely safe on + * 32-bit systems. But the window is tiny, and the effect if + * we are affected is that we will have an obviously bogus + * timestamp on a trace event - i.e. not life threatening. + */ +u64 notrace trace_clock_jiffies(void) +{ + return jiffies_64_to_clock_t(jiffies_64 - INITIAL_JIFFIES); +} /* * trace_clock_global(): special globally coherent trace clock @@ -66,10 +78,14 @@ u64 notrace trace_clock(void) * Used by plugins that need globally coherent timestamps. */ -static u64 prev_trace_clock_time; - -static raw_spinlock_t trace_clock_lock ____cacheline_aligned_in_smp = - (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; +/* keep prev_time and lock in the same cacheline. */ +static struct { + u64 prev_time; + arch_spinlock_t lock; +} trace_clock_struct ____cacheline_aligned_in_smp = + { + .lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED, + }; u64 notrace trace_clock_global(void) { @@ -77,10 +93,10 @@ u64 notrace trace_clock_global(void) int this_cpu; u64 now; - raw_local_irq_save(flags); + local_irq_save(flags); this_cpu = raw_smp_processor_id(); - now = cpu_clock(this_cpu); + now = sched_clock_cpu(this_cpu); /* * If in an NMI context then dont risk lockups and return the * cpu_clock() time: @@ -88,22 +104,34 @@ u64 notrace trace_clock_global(void) if (unlikely(in_nmi())) goto out; - __raw_spin_lock(&trace_clock_lock); + arch_spin_lock(&trace_clock_struct.lock); /* * TODO: if this happens often then maybe we should reset - * my_scd->clock to prev_trace_clock_time+1, to make sure + * my_scd->clock to prev_time+1, to make sure * we start ticking with the local clock from now on? */ - if ((s64)(now - prev_trace_clock_time) < 0) - now = prev_trace_clock_time + 1; + if ((s64)(now - trace_clock_struct.prev_time) < 0) + now = trace_clock_struct.prev_time + 1; - prev_trace_clock_time = now; + trace_clock_struct.prev_time = now; - __raw_spin_unlock(&trace_clock_lock); + arch_spin_unlock(&trace_clock_struct.lock); out: - raw_local_irq_restore(flags); + local_irq_restore(flags); return now; } + +static atomic64_t trace_counter; + +/* + * trace_clock_counter(): simply an atomic counter. + * Use the trace_counter "counter" for cases where you do not care + * about timings, but are interested in strict ordering. + */ +u64 notrace trace_clock_counter(void) +{ + return atomic64_add_return(1, &trace_counter); +} diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h new file mode 100644 index 00000000000..e2d027ac66a --- /dev/null +++ b/kernel/trace/trace_entries.h @@ -0,0 +1,324 @@ +/* + * This file defines the trace event structures that go into the ring + * buffer directly. They are created via macros so that changes for them + * appear in the format file. Using macros will automate this process. + * + * The macro used to create a ftrace data structure is: + * + * FTRACE_ENTRY( name, struct_name, id, structure, print ) + * + * @name: the name used the event name, as well as the name of + * the directory that holds the format file. + * + * @struct_name: the name of the structure that is created. + * + * @id: The event identifier that is used to detect what event + * this is from the ring buffer. + * + * @structure: the structure layout + * + * - __field( type, item ) + * This is equivalent to declaring + * type item; + * in the structure. + * - __array( type, item, size ) + * This is equivalent to declaring + * type item[size]; + * in the structure. + * + * * for structures within structures, the format of the internal + * structure is laid out. This allows the internal structure + * to be deciphered for the format file. Although these macros + * may become out of sync with the internal structure, they + * will create a compile error if it happens. Since the + * internel structures are just tracing helpers, this is not + * an issue. + * + * When an internal structure is used, it should use: + * + * __field_struct( type, item ) + * + * instead of __field. This will prevent it from being shown in + * the output file. The fields in the structure should use. + * + * __field_desc( type, container, item ) + * __array_desc( type, container, item, len ) + * + * type, item and len are the same as __field and __array, but + * container is added. This is the name of the item in + * __field_struct that this is describing. + * + * + * @print: the print format shown to users in the format file. + */ + +/* + * Function trace entry - function address and parent function address: + */ +FTRACE_ENTRY_REG(function, ftrace_entry, + + TRACE_FN, + + F_STRUCT( + __field( unsigned long, ip ) + __field( unsigned long, parent_ip ) + ), + + F_printk(" %lx <-- %lx", __entry->ip, __entry->parent_ip), + + FILTER_TRACE_FN, + + perf_ftrace_event_register +); + +/* Function call entry */ +FTRACE_ENTRY(funcgraph_entry, ftrace_graph_ent_entry, + + TRACE_GRAPH_ENT, + + F_STRUCT( + __field_struct( struct ftrace_graph_ent, graph_ent ) + __field_desc( unsigned long, graph_ent, func ) + __field_desc( int, graph_ent, depth ) + ), + + F_printk("--> %lx (%d)", __entry->func, __entry->depth), + + FILTER_OTHER +); + +/* Function return entry */ +FTRACE_ENTRY(funcgraph_exit, ftrace_graph_ret_entry, + + TRACE_GRAPH_RET, + + F_STRUCT( + __field_struct( struct ftrace_graph_ret, ret ) + __field_desc( unsigned long, ret, func ) + __field_desc( unsigned long long, ret, calltime) + __field_desc( unsigned long long, ret, rettime ) + __field_desc( unsigned long, ret, overrun ) + __field_desc( int, ret, depth ) + ), + + F_printk("<-- %lx (%d) (start: %llx end: %llx) over: %d", + __entry->func, __entry->depth, + __entry->calltime, __entry->rettime, + __entry->depth), + + FILTER_OTHER +); + +/* + * Context switch trace entry - which task (and prio) we switched from/to: + * + * This is used for both wakeup and context switches. We only want + * to create one structure, but we need two outputs for it. + */ +#define FTRACE_CTX_FIELDS \ + __field( unsigned int, prev_pid ) \ + __field( unsigned int, next_pid ) \ + __field( unsigned int, next_cpu ) \ + __field( unsigned char, prev_prio ) \ + __field( unsigned char, prev_state ) \ + __field( unsigned char, next_prio ) \ + __field( unsigned char, next_state ) + +FTRACE_ENTRY(context_switch, ctx_switch_entry, + + TRACE_CTX, + + F_STRUCT( + FTRACE_CTX_FIELDS + ), + + F_printk("%u:%u:%u ==> %u:%u:%u [%03u]", + __entry->prev_pid, __entry->prev_prio, __entry->prev_state, + __entry->next_pid, __entry->next_prio, __entry->next_state, + __entry->next_cpu), + + FILTER_OTHER +); + +/* + * FTRACE_ENTRY_DUP only creates the format file, it will not + * create another structure. + */ +FTRACE_ENTRY_DUP(wakeup, ctx_switch_entry, + + TRACE_WAKE, + + F_STRUCT( + FTRACE_CTX_FIELDS + ), + + F_printk("%u:%u:%u ==+ %u:%u:%u [%03u]", + __entry->prev_pid, __entry->prev_prio, __entry->prev_state, + __entry->next_pid, __entry->next_prio, __entry->next_state, + __entry->next_cpu), + + FILTER_OTHER +); + +/* + * Stack-trace entry: + */ + +#define FTRACE_STACK_ENTRIES 8 + +#ifndef CONFIG_64BIT +# define IP_FMT "%08lx" +#else +# define IP_FMT "%016lx" +#endif + +FTRACE_ENTRY(kernel_stack, stack_entry, + + TRACE_STACK, + + F_STRUCT( + __field( int, size ) + __dynamic_array(unsigned long, caller ) + ), + + F_printk("\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n" + "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n" + "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n", + __entry->caller[0], __entry->caller[1], __entry->caller[2], + __entry->caller[3], __entry->caller[4], __entry->caller[5], + __entry->caller[6], __entry->caller[7]), + + FILTER_OTHER +); + +FTRACE_ENTRY(user_stack, userstack_entry, + + TRACE_USER_STACK, + + F_STRUCT( + __field( unsigned int, tgid ) + __array( unsigned long, caller, FTRACE_STACK_ENTRIES ) + ), + + F_printk("\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n" + "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n" + "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n", + __entry->caller[0], __entry->caller[1], __entry->caller[2], + __entry->caller[3], __entry->caller[4], __entry->caller[5], + __entry->caller[6], __entry->caller[7]), + + FILTER_OTHER +); + +/* + * trace_printk entry: + */ +FTRACE_ENTRY(bprint, bprint_entry, + + TRACE_BPRINT, + + F_STRUCT( + __field( unsigned long, ip ) + __field( const char *, fmt ) + __dynamic_array( u32, buf ) + ), + + F_printk("%pf: %s", + (void *)__entry->ip, __entry->fmt), + + FILTER_OTHER +); + +FTRACE_ENTRY(print, print_entry, + + TRACE_PRINT, + + F_STRUCT( + __field( unsigned long, ip ) + __dynamic_array( char, buf ) + ), + + F_printk("%pf: %s", + (void *)__entry->ip, __entry->buf), + + FILTER_OTHER +); + +FTRACE_ENTRY(bputs, bputs_entry, + + TRACE_BPUTS, + + F_STRUCT( + __field( unsigned long, ip ) + __field( const char *, str ) + ), + + F_printk("%pf: %s", + (void *)__entry->ip, __entry->str), + + FILTER_OTHER +); + +FTRACE_ENTRY(mmiotrace_rw, trace_mmiotrace_rw, + + TRACE_MMIO_RW, + + F_STRUCT( + __field_struct( struct mmiotrace_rw, rw ) + __field_desc( resource_size_t, rw, phys ) + __field_desc( unsigned long, rw, value ) + __field_desc( unsigned long, rw, pc ) + __field_desc( int, rw, map_id ) + __field_desc( unsigned char, rw, opcode ) + __field_desc( unsigned char, rw, width ) + ), + + F_printk("%lx %lx %lx %d %x %x", + (unsigned long)__entry->phys, __entry->value, __entry->pc, + __entry->map_id, __entry->opcode, __entry->width), + + FILTER_OTHER +); + +FTRACE_ENTRY(mmiotrace_map, trace_mmiotrace_map, + + TRACE_MMIO_MAP, + + F_STRUCT( + __field_struct( struct mmiotrace_map, map ) + __field_desc( resource_size_t, map, phys ) + __field_desc( unsigned long, map, virt ) + __field_desc( unsigned long, map, len ) + __field_desc( int, map, map_id ) + __field_desc( unsigned char, map, opcode ) + ), + + F_printk("%lx %lx %lx %d %x", + (unsigned long)__entry->phys, __entry->virt, __entry->len, + __entry->map_id, __entry->opcode), + + FILTER_OTHER +); + + +#define TRACE_FUNC_SIZE 30 +#define TRACE_FILE_SIZE 20 + +FTRACE_ENTRY(branch, trace_branch, + + TRACE_BRANCH, + + F_STRUCT( + __field( unsigned int, line ) + __array( char, func, TRACE_FUNC_SIZE+1 ) + __array( char, file, TRACE_FILE_SIZE+1 ) + __field( char, correct ) + ), + + F_printk("%u:%s:%s (%u)", + __entry->line, + __entry->func, __entry->file, __entry->correct), + + FILTER_OTHER +); + diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c new file mode 100644 index 00000000000..5d12bb407b4 --- /dev/null +++ b/kernel/trace/trace_event_perf.c @@ -0,0 +1,370 @@ +/* + * trace event based perf event profiling/tracing + * + * Copyright (C) 2009 Red Hat Inc, Peter Zijlstra <pzijlstr@redhat.com> + * Copyright (C) 2009-2010 Frederic Weisbecker <fweisbec@gmail.com> + */ + +#include <linux/module.h> +#include <linux/kprobes.h> +#include "trace.h" + +static char __percpu *perf_trace_buf[PERF_NR_CONTEXTS]; + +/* + * Force it to be aligned to unsigned long to avoid misaligned accesses + * suprises + */ +typedef typeof(unsigned long [PERF_MAX_TRACE_SIZE / sizeof(unsigned long)]) + perf_trace_t; + +/* Count the events in use (per event id, not per instance) */ +static int total_ref_count; + +static int perf_trace_event_perm(struct ftrace_event_call *tp_event, + struct perf_event *p_event) +{ + if (tp_event->perf_perm) { + int ret = tp_event->perf_perm(tp_event, p_event); + if (ret) + return ret; + } + + /* The ftrace function trace is allowed only for root. */ + if (ftrace_event_is_function(tp_event)) { + if (perf_paranoid_tracepoint_raw() && !capable(CAP_SYS_ADMIN)) + return -EPERM; + + /* + * We don't allow user space callchains for function trace + * event, due to issues with page faults while tracing page + * fault handler and its overall trickiness nature. + */ + if (!p_event->attr.exclude_callchain_user) + return -EINVAL; + + /* + * Same reason to disable user stack dump as for user space + * callchains above. + */ + if (p_event->attr.sample_type & PERF_SAMPLE_STACK_USER) + return -EINVAL; + } + + /* No tracing, just counting, so no obvious leak */ + if (!(p_event->attr.sample_type & PERF_SAMPLE_RAW)) + return 0; + + /* Some events are ok to be traced by non-root users... */ + if (p_event->attach_state == PERF_ATTACH_TASK) { + if (tp_event->flags & TRACE_EVENT_FL_CAP_ANY) + return 0; + } + + /* + * ...otherwise raw tracepoint data can be a severe data leak, + * only allow root to have these. + */ + if (perf_paranoid_tracepoint_raw() && !capable(CAP_SYS_ADMIN)) + return -EPERM; + + return 0; +} + +static int perf_trace_event_reg(struct ftrace_event_call *tp_event, + struct perf_event *p_event) +{ + struct hlist_head __percpu *list; + int ret = -ENOMEM; + int cpu; + + p_event->tp_event = tp_event; + if (tp_event->perf_refcount++ > 0) + return 0; + + list = alloc_percpu(struct hlist_head); + if (!list) + goto fail; + + for_each_possible_cpu(cpu) + INIT_HLIST_HEAD(per_cpu_ptr(list, cpu)); + + tp_event->perf_events = list; + + if (!total_ref_count) { + char __percpu *buf; + int i; + + for (i = 0; i < PERF_NR_CONTEXTS; i++) { + buf = (char __percpu *)alloc_percpu(perf_trace_t); + if (!buf) + goto fail; + + perf_trace_buf[i] = buf; + } + } + + ret = tp_event->class->reg(tp_event, TRACE_REG_PERF_REGISTER, NULL); + if (ret) + goto fail; + + total_ref_count++; + return 0; + +fail: + if (!total_ref_count) { + int i; + + for (i = 0; i < PERF_NR_CONTEXTS; i++) { + free_percpu(perf_trace_buf[i]); + perf_trace_buf[i] = NULL; + } + } + + if (!--tp_event->perf_refcount) { + free_percpu(tp_event->perf_events); + tp_event->perf_events = NULL; + } + + return ret; +} + +static void perf_trace_event_unreg(struct perf_event *p_event) +{ + struct ftrace_event_call *tp_event = p_event->tp_event; + int i; + + if (--tp_event->perf_refcount > 0) + goto out; + + tp_event->class->reg(tp_event, TRACE_REG_PERF_UNREGISTER, NULL); + + /* + * Ensure our callback won't be called anymore. The buffers + * will be freed after that. + */ + tracepoint_synchronize_unregister(); + + free_percpu(tp_event->perf_events); + tp_event->perf_events = NULL; + + if (!--total_ref_count) { + for (i = 0; i < PERF_NR_CONTEXTS; i++) { + free_percpu(perf_trace_buf[i]); + perf_trace_buf[i] = NULL; + } + } +out: + module_put(tp_event->mod); +} + +static int perf_trace_event_open(struct perf_event *p_event) +{ + struct ftrace_event_call *tp_event = p_event->tp_event; + return tp_event->class->reg(tp_event, TRACE_REG_PERF_OPEN, p_event); +} + +static void perf_trace_event_close(struct perf_event *p_event) +{ + struct ftrace_event_call *tp_event = p_event->tp_event; + tp_event->class->reg(tp_event, TRACE_REG_PERF_CLOSE, p_event); +} + +static int perf_trace_event_init(struct ftrace_event_call *tp_event, + struct perf_event *p_event) +{ + int ret; + + ret = perf_trace_event_perm(tp_event, p_event); + if (ret) + return ret; + + ret = perf_trace_event_reg(tp_event, p_event); + if (ret) + return ret; + + ret = perf_trace_event_open(p_event); + if (ret) { + perf_trace_event_unreg(p_event); + return ret; + } + + return 0; +} + +int perf_trace_init(struct perf_event *p_event) +{ + struct ftrace_event_call *tp_event; + u64 event_id = p_event->attr.config; + int ret = -EINVAL; + + mutex_lock(&event_mutex); + list_for_each_entry(tp_event, &ftrace_events, list) { + if (tp_event->event.type == event_id && + tp_event->class && tp_event->class->reg && + try_module_get(tp_event->mod)) { + ret = perf_trace_event_init(tp_event, p_event); + if (ret) + module_put(tp_event->mod); + break; + } + } + mutex_unlock(&event_mutex); + + return ret; +} + +void perf_trace_destroy(struct perf_event *p_event) +{ + mutex_lock(&event_mutex); + perf_trace_event_close(p_event); + perf_trace_event_unreg(p_event); + mutex_unlock(&event_mutex); +} + +int perf_trace_add(struct perf_event *p_event, int flags) +{ + struct ftrace_event_call *tp_event = p_event->tp_event; + struct hlist_head __percpu *pcpu_list; + struct hlist_head *list; + + pcpu_list = tp_event->perf_events; + if (WARN_ON_ONCE(!pcpu_list)) + return -EINVAL; + + if (!(flags & PERF_EF_START)) + p_event->hw.state = PERF_HES_STOPPED; + + list = this_cpu_ptr(pcpu_list); + hlist_add_head_rcu(&p_event->hlist_entry, list); + + return tp_event->class->reg(tp_event, TRACE_REG_PERF_ADD, p_event); +} + +void perf_trace_del(struct perf_event *p_event, int flags) +{ + struct ftrace_event_call *tp_event = p_event->tp_event; + hlist_del_rcu(&p_event->hlist_entry); + tp_event->class->reg(tp_event, TRACE_REG_PERF_DEL, p_event); +} + +void *perf_trace_buf_prepare(int size, unsigned short type, + struct pt_regs *regs, int *rctxp) +{ + struct trace_entry *entry; + unsigned long flags; + char *raw_data; + int pc; + + BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(unsigned long)); + + if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, + "perf buffer not large enough")) + return NULL; + + pc = preempt_count(); + + *rctxp = perf_swevent_get_recursion_context(); + if (*rctxp < 0) + return NULL; + + raw_data = this_cpu_ptr(perf_trace_buf[*rctxp]); + + /* zero the dead bytes from align to not leak stack to user */ + memset(&raw_data[size - sizeof(u64)], 0, sizeof(u64)); + + entry = (struct trace_entry *)raw_data; + local_save_flags(flags); + tracing_generic_entry_update(entry, flags, pc); + entry->type = type; + + return raw_data; +} +EXPORT_SYMBOL_GPL(perf_trace_buf_prepare); +NOKPROBE_SYMBOL(perf_trace_buf_prepare); + +#ifdef CONFIG_FUNCTION_TRACER +static void +perf_ftrace_function_call(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *ops, struct pt_regs *pt_regs) +{ + struct ftrace_entry *entry; + struct hlist_head *head; + struct pt_regs regs; + int rctx; + + head = this_cpu_ptr(event_function.perf_events); + if (hlist_empty(head)) + return; + +#define ENTRY_SIZE (ALIGN(sizeof(struct ftrace_entry) + sizeof(u32), \ + sizeof(u64)) - sizeof(u32)) + + BUILD_BUG_ON(ENTRY_SIZE > PERF_MAX_TRACE_SIZE); + + perf_fetch_caller_regs(®s); + + entry = perf_trace_buf_prepare(ENTRY_SIZE, TRACE_FN, NULL, &rctx); + if (!entry) + return; + + entry->ip = ip; + entry->parent_ip = parent_ip; + perf_trace_buf_submit(entry, ENTRY_SIZE, rctx, 0, + 1, ®s, head, NULL); + +#undef ENTRY_SIZE +} + +static int perf_ftrace_function_register(struct perf_event *event) +{ + struct ftrace_ops *ops = &event->ftrace_ops; + + ops->flags |= FTRACE_OPS_FL_CONTROL; + ops->func = perf_ftrace_function_call; + return register_ftrace_function(ops); +} + +static int perf_ftrace_function_unregister(struct perf_event *event) +{ + struct ftrace_ops *ops = &event->ftrace_ops; + int ret = unregister_ftrace_function(ops); + ftrace_free_filter(ops); + return ret; +} + +static void perf_ftrace_function_enable(struct perf_event *event) +{ + ftrace_function_local_enable(&event->ftrace_ops); +} + +static void perf_ftrace_function_disable(struct perf_event *event) +{ + ftrace_function_local_disable(&event->ftrace_ops); +} + +int perf_ftrace_event_register(struct ftrace_event_call *call, + enum trace_reg type, void *data) +{ + switch (type) { + case TRACE_REG_REGISTER: + case TRACE_REG_UNREGISTER: + break; + case TRACE_REG_PERF_REGISTER: + case TRACE_REG_PERF_UNREGISTER: + return 0; + case TRACE_REG_PERF_OPEN: + return perf_ftrace_function_register(data); + case TRACE_REG_PERF_CLOSE: + return perf_ftrace_function_unregister(data); + case TRACE_REG_PERF_ADD: + perf_ftrace_function_enable(data); + return 0; + case TRACE_REG_PERF_DEL: + perf_ftrace_function_disable(data); + return 0; + } + + return -EINVAL; +} +#endif /* CONFIG_FUNCTION_TRACER */ diff --git a/kernel/trace/trace_event_profile.c b/kernel/trace/trace_event_profile.c deleted file mode 100644 index 5b5895afecf..00000000000 --- a/kernel/trace/trace_event_profile.c +++ /dev/null @@ -1,39 +0,0 @@ -/* - * trace event based perf counter profiling - * - * Copyright (C) 2009 Red Hat Inc, Peter Zijlstra <pzijlstr@redhat.com> - * - */ - -#include "trace.h" - -int ftrace_profile_enable(int event_id) -{ - struct ftrace_event_call *event; - int ret = -EINVAL; - - mutex_lock(&event_mutex); - list_for_each_entry(event, &ftrace_events, list) { - if (event->id == event_id) { - ret = event->profile_enable(event); - break; - } - } - mutex_unlock(&event_mutex); - - return ret; -} - -void ftrace_profile_disable(int event_id) -{ - struct ftrace_event_call *event; - - mutex_lock(&event_mutex); - list_for_each_entry(event, &ftrace_events, list) { - if (event->id == event_id) { - event->profile_disable(event); - break; - } - } - mutex_unlock(&event_mutex); -} diff --git a/kernel/trace/trace_event_types.h b/kernel/trace/trace_event_types.h deleted file mode 100644 index 5e32e375134..00000000000 --- a/kernel/trace/trace_event_types.h +++ /dev/null @@ -1,175 +0,0 @@ -#undef TRACE_SYSTEM -#define TRACE_SYSTEM ftrace - -/* - * We cheat and use the proto type field as the ID - * and args as the entry type (minus 'struct') - */ -TRACE_EVENT_FORMAT(function, TRACE_FN, ftrace_entry, ignore, - TRACE_STRUCT( - TRACE_FIELD(unsigned long, ip, ip) - TRACE_FIELD(unsigned long, parent_ip, parent_ip) - ), - TP_RAW_FMT(" %lx <-- %lx") -); - -TRACE_EVENT_FORMAT(funcgraph_entry, TRACE_GRAPH_ENT, - ftrace_graph_ent_entry, ignore, - TRACE_STRUCT( - TRACE_FIELD(unsigned long, graph_ent.func, func) - TRACE_FIELD(int, graph_ent.depth, depth) - ), - TP_RAW_FMT("--> %lx (%d)") -); - -TRACE_EVENT_FORMAT(funcgraph_exit, TRACE_GRAPH_RET, - ftrace_graph_ret_entry, ignore, - TRACE_STRUCT( - TRACE_FIELD(unsigned long, ret.func, func) - TRACE_FIELD(int, ret.depth, depth) - ), - TP_RAW_FMT("<-- %lx (%d)") -); - -TRACE_EVENT_FORMAT(wakeup, TRACE_WAKE, ctx_switch_entry, ignore, - TRACE_STRUCT( - TRACE_FIELD(unsigned int, prev_pid, prev_pid) - TRACE_FIELD(unsigned char, prev_prio, prev_prio) - TRACE_FIELD(unsigned char, prev_state, prev_state) - TRACE_FIELD(unsigned int, next_pid, next_pid) - TRACE_FIELD(unsigned char, next_prio, next_prio) - TRACE_FIELD(unsigned char, next_state, next_state) - TRACE_FIELD(unsigned int, next_cpu, next_cpu) - ), - TP_RAW_FMT("%u:%u:%u ==+ %u:%u:%u [%03u]") -); - -TRACE_EVENT_FORMAT(context_switch, TRACE_CTX, ctx_switch_entry, ignore, - TRACE_STRUCT( - TRACE_FIELD(unsigned int, prev_pid, prev_pid) - TRACE_FIELD(unsigned char, prev_prio, prev_prio) - TRACE_FIELD(unsigned char, prev_state, prev_state) - TRACE_FIELD(unsigned int, next_pid, next_pid) - TRACE_FIELD(unsigned char, next_prio, next_prio) - TRACE_FIELD(unsigned char, next_state, next_state) - TRACE_FIELD(unsigned int, next_cpu, next_cpu) - ), - TP_RAW_FMT("%u:%u:%u ==+ %u:%u:%u [%03u]") -); - -TRACE_EVENT_FORMAT_NOFILTER(special, TRACE_SPECIAL, special_entry, ignore, - TRACE_STRUCT( - TRACE_FIELD(unsigned long, arg1, arg1) - TRACE_FIELD(unsigned long, arg2, arg2) - TRACE_FIELD(unsigned long, arg3, arg3) - ), - TP_RAW_FMT("(%08lx) (%08lx) (%08lx)") -); - -/* - * Stack-trace entry: - */ - -/* #define FTRACE_STACK_ENTRIES 8 */ - -TRACE_EVENT_FORMAT(kernel_stack, TRACE_STACK, stack_entry, ignore, - TRACE_STRUCT( - TRACE_FIELD(unsigned long, caller[0], stack0) - TRACE_FIELD(unsigned long, caller[1], stack1) - TRACE_FIELD(unsigned long, caller[2], stack2) - TRACE_FIELD(unsigned long, caller[3], stack3) - TRACE_FIELD(unsigned long, caller[4], stack4) - TRACE_FIELD(unsigned long, caller[5], stack5) - TRACE_FIELD(unsigned long, caller[6], stack6) - TRACE_FIELD(unsigned long, caller[7], stack7) - ), - TP_RAW_FMT("\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n" - "\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n") -); - -TRACE_EVENT_FORMAT(user_stack, TRACE_USER_STACK, userstack_entry, ignore, - TRACE_STRUCT( - TRACE_FIELD(unsigned long, caller[0], stack0) - TRACE_FIELD(unsigned long, caller[1], stack1) - TRACE_FIELD(unsigned long, caller[2], stack2) - TRACE_FIELD(unsigned long, caller[3], stack3) - TRACE_FIELD(unsigned long, caller[4], stack4) - TRACE_FIELD(unsigned long, caller[5], stack5) - TRACE_FIELD(unsigned long, caller[6], stack6) - TRACE_FIELD(unsigned long, caller[7], stack7) - ), - TP_RAW_FMT("\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n" - "\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n") -); - -TRACE_EVENT_FORMAT(bprint, TRACE_BPRINT, bprint_entry, ignore, - TRACE_STRUCT( - TRACE_FIELD(unsigned long, ip, ip) - TRACE_FIELD(char *, fmt, fmt) - TRACE_FIELD_ZERO_CHAR(buf) - ), - TP_RAW_FMT("%08lx (%d) fmt:%p %s") -); - -TRACE_EVENT_FORMAT(print, TRACE_PRINT, print_entry, ignore, - TRACE_STRUCT( - TRACE_FIELD(unsigned long, ip, ip) - TRACE_FIELD_ZERO_CHAR(buf) - ), - TP_RAW_FMT("%08lx (%d) fmt:%p %s") -); - -TRACE_EVENT_FORMAT(branch, TRACE_BRANCH, trace_branch, ignore, - TRACE_STRUCT( - TRACE_FIELD(unsigned int, line, line) - TRACE_FIELD_SPECIAL(char func[TRACE_FUNC_SIZE+1], func, - TRACE_FUNC_SIZE+1, func) - TRACE_FIELD_SPECIAL(char file[TRACE_FUNC_SIZE+1], file, - TRACE_FUNC_SIZE+1, file) - TRACE_FIELD(char, correct, correct) - ), - TP_RAW_FMT("%u:%s:%s (%u)") -); - -TRACE_EVENT_FORMAT(hw_branch, TRACE_HW_BRANCHES, hw_branch_entry, ignore, - TRACE_STRUCT( - TRACE_FIELD(u64, from, from) - TRACE_FIELD(u64, to, to) - ), - TP_RAW_FMT("from: %llx to: %llx") -); - -TRACE_EVENT_FORMAT(power, TRACE_POWER, trace_power, ignore, - TRACE_STRUCT( - TRACE_FIELD_SIGN(ktime_t, state_data.stamp, stamp, 1) - TRACE_FIELD_SIGN(ktime_t, state_data.end, end, 1) - TRACE_FIELD(int, state_data.type, type) - TRACE_FIELD(int, state_data.state, state) - ), - TP_RAW_FMT("%llx->%llx type:%u state:%u") -); - -TRACE_EVENT_FORMAT(kmem_alloc, TRACE_KMEM_ALLOC, kmemtrace_alloc_entry, ignore, - TRACE_STRUCT( - TRACE_FIELD(enum kmemtrace_type_id, type_id, type_id) - TRACE_FIELD(unsigned long, call_site, call_site) - TRACE_FIELD(const void *, ptr, ptr) - TRACE_FIELD(size_t, bytes_req, bytes_req) - TRACE_FIELD(size_t, bytes_alloc, bytes_alloc) - TRACE_FIELD(gfp_t, gfp_flags, gfp_flags) - TRACE_FIELD(int, node, node) - ), - TP_RAW_FMT("type:%u call_site:%lx ptr:%p req:%lu alloc:%lu" - " flags:%x node:%d") -); - -TRACE_EVENT_FORMAT(kmem_free, TRACE_KMEM_FREE, kmemtrace_free_entry, ignore, - TRACE_STRUCT( - TRACE_FIELD(enum kmemtrace_type_id, type_id, type_id) - TRACE_FIELD(unsigned long, call_site, call_site) - TRACE_FIELD(const void *, ptr, ptr) - ), - TP_RAW_FMT("type:%u call_site:%lx ptr:%p") -); - -#undef TRACE_SYSTEM diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 53c8fd376a8..2de53628689 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -15,135 +15,520 @@ #include <linux/uaccess.h> #include <linux/module.h> #include <linux/ctype.h> +#include <linux/slab.h> #include <linux/delay.h> +#include <asm/setup.h> + #include "trace_output.h" +#undef TRACE_SYSTEM #define TRACE_SYSTEM "TRACE_SYSTEM" DEFINE_MUTEX(event_mutex); LIST_HEAD(ftrace_events); +static LIST_HEAD(ftrace_common_fields); + +#define GFP_TRACE (GFP_KERNEL | __GFP_ZERO) + +static struct kmem_cache *field_cachep; +static struct kmem_cache *file_cachep; + +#define SYSTEM_FL_FREE_NAME (1 << 31) + +static inline int system_refcount(struct event_subsystem *system) +{ + return system->ref_count & ~SYSTEM_FL_FREE_NAME; +} + +static int system_refcount_inc(struct event_subsystem *system) +{ + return (system->ref_count++) & ~SYSTEM_FL_FREE_NAME; +} + +static int system_refcount_dec(struct event_subsystem *system) +{ + return (--system->ref_count) & ~SYSTEM_FL_FREE_NAME; +} + +/* Double loops, do not use break, only goto's work */ +#define do_for_each_event_file(tr, file) \ + list_for_each_entry(tr, &ftrace_trace_arrays, list) { \ + list_for_each_entry(file, &tr->events, list) -int trace_define_field(struct ftrace_event_call *call, char *type, - char *name, int offset, int size, int is_signed) +#define do_for_each_event_file_safe(tr, file) \ + list_for_each_entry(tr, &ftrace_trace_arrays, list) { \ + struct ftrace_event_file *___n; \ + list_for_each_entry_safe(file, ___n, &tr->events, list) + +#define while_for_each_event_file() \ + } + +static struct list_head * +trace_get_fields(struct ftrace_event_call *event_call) +{ + if (!event_call->class->get_fields) + return &event_call->class->fields; + return event_call->class->get_fields(event_call); +} + +static struct ftrace_event_field * +__find_event_field(struct list_head *head, char *name) +{ + struct ftrace_event_field *field; + + list_for_each_entry(field, head, link) { + if (!strcmp(field->name, name)) + return field; + } + + return NULL; +} + +struct ftrace_event_field * +trace_find_event_field(struct ftrace_event_call *call, char *name) { struct ftrace_event_field *field; + struct list_head *head; + + field = __find_event_field(&ftrace_common_fields, name); + if (field) + return field; - field = kzalloc(sizeof(*field), GFP_KERNEL); + head = trace_get_fields(call); + return __find_event_field(head, name); +} + +static int __trace_define_field(struct list_head *head, const char *type, + const char *name, int offset, int size, + int is_signed, int filter_type) +{ + struct ftrace_event_field *field; + + field = kmem_cache_alloc(field_cachep, GFP_TRACE); if (!field) - goto err; + return -ENOMEM; - field->name = kstrdup(name, GFP_KERNEL); - if (!field->name) - goto err; + field->name = name; + field->type = type; - field->type = kstrdup(type, GFP_KERNEL); - if (!field->type) - goto err; + if (filter_type == FILTER_OTHER) + field->filter_type = filter_assign_type(type); + else + field->filter_type = filter_type; field->offset = offset; field->size = size; field->is_signed = is_signed; - list_add(&field->link, &call->fields); + + list_add(&field->link, head); return 0; +} -err: - if (field) { - kfree(field->name); - kfree(field->type); - } - kfree(field); +int trace_define_field(struct ftrace_event_call *call, const char *type, + const char *name, int offset, int size, int is_signed, + int filter_type) +{ + struct list_head *head; - return -ENOMEM; + if (WARN_ON(!call->class)) + return 0; + + head = trace_get_fields(call); + return __trace_define_field(head, type, name, offset, size, + is_signed, filter_type); } EXPORT_SYMBOL_GPL(trace_define_field); -#ifdef CONFIG_MODULES +#define __common_field(type, item) \ + ret = __trace_define_field(&ftrace_common_fields, #type, \ + "common_" #item, \ + offsetof(typeof(ent), item), \ + sizeof(ent.item), \ + is_signed_type(type), FILTER_OTHER); \ + if (ret) \ + return ret; + +static int trace_define_common_fields(void) +{ + int ret; + struct trace_entry ent; + + __common_field(unsigned short, type); + __common_field(unsigned char, flags); + __common_field(unsigned char, preempt_count); + __common_field(int, pid); + + return ret; +} static void trace_destroy_fields(struct ftrace_event_call *call) { struct ftrace_event_field *field, *next; + struct list_head *head; - list_for_each_entry_safe(field, next, &call->fields, link) { + head = trace_get_fields(call); + list_for_each_entry_safe(field, next, head, link) { list_del(&field->link); - kfree(field->type); - kfree(field->name); - kfree(field); + kmem_cache_free(field_cachep, field); } } -#endif /* CONFIG_MODULES */ +int trace_event_raw_init(struct ftrace_event_call *call) +{ + int id; + + id = register_ftrace_event(&call->event); + if (!id) + return -ENODEV; + + return 0; +} +EXPORT_SYMBOL_GPL(trace_event_raw_init); + +void *ftrace_event_buffer_reserve(struct ftrace_event_buffer *fbuffer, + struct ftrace_event_file *ftrace_file, + unsigned long len) +{ + struct ftrace_event_call *event_call = ftrace_file->event_call; + + local_save_flags(fbuffer->flags); + fbuffer->pc = preempt_count(); + fbuffer->ftrace_file = ftrace_file; + + fbuffer->event = + trace_event_buffer_lock_reserve(&fbuffer->buffer, ftrace_file, + event_call->event.type, len, + fbuffer->flags, fbuffer->pc); + if (!fbuffer->event) + return NULL; + + fbuffer->entry = ring_buffer_event_data(fbuffer->event); + return fbuffer->entry; +} +EXPORT_SYMBOL_GPL(ftrace_event_buffer_reserve); + +void ftrace_event_buffer_commit(struct ftrace_event_buffer *fbuffer) +{ + event_trigger_unlock_commit(fbuffer->ftrace_file, fbuffer->buffer, + fbuffer->event, fbuffer->entry, + fbuffer->flags, fbuffer->pc); +} +EXPORT_SYMBOL_GPL(ftrace_event_buffer_commit); + +int ftrace_event_reg(struct ftrace_event_call *call, + enum trace_reg type, void *data) +{ + struct ftrace_event_file *file = data; + + WARN_ON(!(call->flags & TRACE_EVENT_FL_TRACEPOINT)); + switch (type) { + case TRACE_REG_REGISTER: + return tracepoint_probe_register(call->tp, + call->class->probe, + file); + case TRACE_REG_UNREGISTER: + tracepoint_probe_unregister(call->tp, + call->class->probe, + file); + return 0; -static void ftrace_event_enable_disable(struct ftrace_event_call *call, - int enable) +#ifdef CONFIG_PERF_EVENTS + case TRACE_REG_PERF_REGISTER: + return tracepoint_probe_register(call->tp, + call->class->perf_probe, + call); + case TRACE_REG_PERF_UNREGISTER: + tracepoint_probe_unregister(call->tp, + call->class->perf_probe, + call); + return 0; + case TRACE_REG_PERF_OPEN: + case TRACE_REG_PERF_CLOSE: + case TRACE_REG_PERF_ADD: + case TRACE_REG_PERF_DEL: + return 0; +#endif + } + return 0; +} +EXPORT_SYMBOL_GPL(ftrace_event_reg); + +void trace_event_enable_cmd_record(bool enable) { + struct ftrace_event_file *file; + struct trace_array *tr; + + mutex_lock(&event_mutex); + do_for_each_event_file(tr, file) { + + if (!(file->flags & FTRACE_EVENT_FL_ENABLED)) + continue; + + if (enable) { + tracing_start_cmdline_record(); + set_bit(FTRACE_EVENT_FL_RECORDED_CMD_BIT, &file->flags); + } else { + tracing_stop_cmdline_record(); + clear_bit(FTRACE_EVENT_FL_RECORDED_CMD_BIT, &file->flags); + } + } while_for_each_event_file(); + mutex_unlock(&event_mutex); +} + +static int __ftrace_event_enable_disable(struct ftrace_event_file *file, + int enable, int soft_disable) +{ + struct ftrace_event_call *call = file->event_call; + int ret = 0; + int disable; + switch (enable) { case 0: - if (call->enabled) { - call->enabled = 0; - tracing_stop_cmdline_record(); - call->unregfunc(); + /* + * When soft_disable is set and enable is cleared, the sm_ref + * reference counter is decremented. If it reaches 0, we want + * to clear the SOFT_DISABLED flag but leave the event in the + * state that it was. That is, if the event was enabled and + * SOFT_DISABLED isn't set, then do nothing. But if SOFT_DISABLED + * is set we do not want the event to be enabled before we + * clear the bit. + * + * When soft_disable is not set but the SOFT_MODE flag is, + * we do nothing. Do not disable the tracepoint, otherwise + * "soft enable"s (clearing the SOFT_DISABLED bit) wont work. + */ + if (soft_disable) { + if (atomic_dec_return(&file->sm_ref) > 0) + break; + disable = file->flags & FTRACE_EVENT_FL_SOFT_DISABLED; + clear_bit(FTRACE_EVENT_FL_SOFT_MODE_BIT, &file->flags); + } else + disable = !(file->flags & FTRACE_EVENT_FL_SOFT_MODE); + + if (disable && (file->flags & FTRACE_EVENT_FL_ENABLED)) { + clear_bit(FTRACE_EVENT_FL_ENABLED_BIT, &file->flags); + if (file->flags & FTRACE_EVENT_FL_RECORDED_CMD) { + tracing_stop_cmdline_record(); + clear_bit(FTRACE_EVENT_FL_RECORDED_CMD_BIT, &file->flags); + } + call->class->reg(call, TRACE_REG_UNREGISTER, file); } + /* If in SOFT_MODE, just set the SOFT_DISABLE_BIT, else clear it */ + if (file->flags & FTRACE_EVENT_FL_SOFT_MODE) + set_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags); + else + clear_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags); break; case 1: - if (!call->enabled) { - call->enabled = 1; - tracing_start_cmdline_record(); - call->regfunc(); + /* + * When soft_disable is set and enable is set, we want to + * register the tracepoint for the event, but leave the event + * as is. That means, if the event was already enabled, we do + * nothing (but set SOFT_MODE). If the event is disabled, we + * set SOFT_DISABLED before enabling the event tracepoint, so + * it still seems to be disabled. + */ + if (!soft_disable) + clear_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags); + else { + if (atomic_inc_return(&file->sm_ref) > 1) + break; + set_bit(FTRACE_EVENT_FL_SOFT_MODE_BIT, &file->flags); + } + + if (!(file->flags & FTRACE_EVENT_FL_ENABLED)) { + + /* Keep the event disabled, when going to SOFT_MODE. */ + if (soft_disable) + set_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags); + + if (trace_flags & TRACE_ITER_RECORD_CMD) { + tracing_start_cmdline_record(); + set_bit(FTRACE_EVENT_FL_RECORDED_CMD_BIT, &file->flags); + } + ret = call->class->reg(call, TRACE_REG_REGISTER, file); + if (ret) { + tracing_stop_cmdline_record(); + pr_info("event trace: Could not enable event " + "%s\n", ftrace_event_name(call)); + break; + } + set_bit(FTRACE_EVENT_FL_ENABLED_BIT, &file->flags); + + /* WAS_ENABLED gets set but never cleared. */ + call->flags |= TRACE_EVENT_FL_WAS_ENABLED; } break; } + + return ret; } -static void ftrace_clear_events(void) +int trace_event_enable_disable(struct ftrace_event_file *file, + int enable, int soft_disable) { - struct ftrace_event_call *call; + return __ftrace_event_enable_disable(file, enable, soft_disable); +} + +static int ftrace_event_enable_disable(struct ftrace_event_file *file, + int enable) +{ + return __ftrace_event_enable_disable(file, enable, 0); +} + +static void ftrace_clear_events(struct trace_array *tr) +{ + struct ftrace_event_file *file; mutex_lock(&event_mutex); - list_for_each_entry(call, &ftrace_events, list) { - ftrace_event_enable_disable(call, 0); + list_for_each_entry(file, &tr->events, list) { + ftrace_event_enable_disable(file, 0); } mutex_unlock(&event_mutex); } +static void __put_system(struct event_subsystem *system) +{ + struct event_filter *filter = system->filter; + + WARN_ON_ONCE(system_refcount(system) == 0); + if (system_refcount_dec(system)) + return; + + list_del(&system->list); + + if (filter) { + kfree(filter->filter_string); + kfree(filter); + } + if (system->ref_count & SYSTEM_FL_FREE_NAME) + kfree(system->name); + kfree(system); +} + +static void __get_system(struct event_subsystem *system) +{ + WARN_ON_ONCE(system_refcount(system) == 0); + system_refcount_inc(system); +} + +static void __get_system_dir(struct ftrace_subsystem_dir *dir) +{ + WARN_ON_ONCE(dir->ref_count == 0); + dir->ref_count++; + __get_system(dir->subsystem); +} + +static void __put_system_dir(struct ftrace_subsystem_dir *dir) +{ + WARN_ON_ONCE(dir->ref_count == 0); + /* If the subsystem is about to be freed, the dir must be too */ + WARN_ON_ONCE(system_refcount(dir->subsystem) == 1 && dir->ref_count != 1); + + __put_system(dir->subsystem); + if (!--dir->ref_count) + kfree(dir); +} + +static void put_system(struct ftrace_subsystem_dir *dir) +{ + mutex_lock(&event_mutex); + __put_system_dir(dir); + mutex_unlock(&event_mutex); +} + +static void remove_subsystem(struct ftrace_subsystem_dir *dir) +{ + if (!dir) + return; + + if (!--dir->nr_events) { + debugfs_remove_recursive(dir->entry); + list_del(&dir->list); + __put_system_dir(dir); + } +} + +static void remove_event_file_dir(struct ftrace_event_file *file) +{ + struct dentry *dir = file->dir; + struct dentry *child; + + if (dir) { + spin_lock(&dir->d_lock); /* probably unneeded */ + list_for_each_entry(child, &dir->d_subdirs, d_u.d_child) { + if (child->d_inode) /* probably unneeded */ + child->d_inode->i_private = NULL; + } + spin_unlock(&dir->d_lock); + + debugfs_remove_recursive(dir); + } + + list_del(&file->list); + remove_subsystem(file->system); + free_event_filter(file->filter); + kmem_cache_free(file_cachep, file); +} + /* * __ftrace_set_clr_event(NULL, NULL, NULL, set) will set/unset all events. */ -static int __ftrace_set_clr_event(const char *match, const char *sub, - const char *event, int set) +static int +__ftrace_set_clr_event_nolock(struct trace_array *tr, const char *match, + const char *sub, const char *event, int set) { + struct ftrace_event_file *file; struct ftrace_event_call *call; + const char *name; int ret = -EINVAL; - mutex_lock(&event_mutex); - list_for_each_entry(call, &ftrace_events, list) { + list_for_each_entry(file, &tr->events, list) { - if (!call->name || !call->regfunc) + call = file->event_call; + name = ftrace_event_name(call); + + if (!name || !call->class || !call->class->reg) + continue; + + if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) continue; if (match && - strcmp(match, call->name) != 0 && - strcmp(match, call->system) != 0) + strcmp(match, name) != 0 && + strcmp(match, call->class->system) != 0) continue; - if (sub && strcmp(sub, call->system) != 0) + if (sub && strcmp(sub, call->class->system) != 0) continue; - if (event && strcmp(event, call->name) != 0) + if (event && strcmp(event, name) != 0) continue; - ftrace_event_enable_disable(call, set); + ftrace_event_enable_disable(file, set); ret = 0; } + + return ret; +} + +static int __ftrace_set_clr_event(struct trace_array *tr, const char *match, + const char *sub, const char *event, int set) +{ + int ret; + + mutex_lock(&event_mutex); + ret = __ftrace_set_clr_event_nolock(tr, match, sub, event, set); mutex_unlock(&event_mutex); return ret; } -static int ftrace_set_clr_event(char *buf, int set) +static int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set) { char *event = NULL, *sub = NULL, *match; @@ -171,7 +556,7 @@ static int ftrace_set_clr_event(char *buf, int set) event = NULL; } - return __ftrace_set_clr_event(match, sub, event, set); + return __ftrace_set_clr_event(tr, match, sub, event, set); } /** @@ -188,8 +573,14 @@ static int ftrace_set_clr_event(char *buf, int set) */ int trace_set_clr_event(const char *system, const char *event, int set) { - return __ftrace_set_clr_event(NULL, system, event, set); + struct trace_array *tr = top_trace_array(); + + if (!tr) + return -ENODEV; + + return __ftrace_set_clr_event(tr, NULL, system, event, set); } +EXPORT_SYMBOL_GPL(trace_set_clr_event); /* 128 should be much more than enough */ #define EVENT_BUF_SIZE 127 @@ -198,73 +589,40 @@ static ssize_t ftrace_event_write(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos) { - size_t read = 0; - int i, set = 1; - ssize_t ret; - char *buf; - char ch; + struct trace_parser parser; + struct seq_file *m = file->private_data; + struct trace_array *tr = m->private; + ssize_t read, ret; - if (!cnt || cnt < 0) + if (!cnt) return 0; ret = tracing_update_buffers(); if (ret < 0) return ret; - ret = get_user(ch, ubuf++); - if (ret) - return ret; - read++; - cnt--; - - /* skip white space */ - while (cnt && isspace(ch)) { - ret = get_user(ch, ubuf++); - if (ret) - return ret; - read++; - cnt--; - } - - /* Only white space found? */ - if (isspace(ch)) { - file->f_pos += read; - ret = read; - return ret; - } - - buf = kmalloc(EVENT_BUF_SIZE+1, GFP_KERNEL); - if (!buf) + if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1)) return -ENOMEM; - if (cnt > EVENT_BUF_SIZE) - cnt = EVENT_BUF_SIZE; + read = trace_get_user(&parser, ubuf, cnt, ppos); - i = 0; - while (cnt && !isspace(ch)) { - if (!i && ch == '!') + if (read >= 0 && trace_parser_loaded((&parser))) { + int set = 1; + + if (*parser.buffer == '!') set = 0; - else - buf[i++] = ch; - ret = get_user(ch, ubuf++); + parser.buffer[parser.idx] = 0; + + ret = ftrace_set_clr_event(tr, parser.buffer + !set, set); if (ret) - goto out_free; - read++; - cnt--; + goto out_put; } - buf[i] = 0; - - file->f_pos += read; - - ret = ftrace_set_clr_event(buf, set); - if (ret) - goto out_free; ret = read; - out_free: - kfree(buf); + out_put: + trace_parser_put(&parser); return ret; } @@ -272,95 +630,83 @@ ftrace_event_write(struct file *file, const char __user *ubuf, static void * t_next(struct seq_file *m, void *v, loff_t *pos) { - struct list_head *list = m->private; + struct ftrace_event_file *file = v; struct ftrace_event_call *call; + struct trace_array *tr = m->private; (*pos)++; - for (;;) { - if (list == &ftrace_events) - return NULL; - - call = list_entry(list, struct ftrace_event_call, list); - + list_for_each_entry_continue(file, &tr->events, list) { + call = file->event_call; /* * The ftrace subsystem is for showing formats only. * They can not be enabled or disabled via the event files. */ - if (call->regfunc) - break; - - list = list->next; + if (call->class && call->class->reg) + return file; } - m->private = list->next; - - return call; + return NULL; } static void *t_start(struct seq_file *m, loff_t *pos) { - struct ftrace_event_call *call = NULL; + struct ftrace_event_file *file; + struct trace_array *tr = m->private; loff_t l; mutex_lock(&event_mutex); - m->private = ftrace_events.next; + file = list_entry(&tr->events, struct ftrace_event_file, list); for (l = 0; l <= *pos; ) { - call = t_next(m, NULL, &l); - if (!call) + file = t_next(m, file, &l); + if (!file) break; } - return call; + return file; } static void * s_next(struct seq_file *m, void *v, loff_t *pos) { - struct list_head *list = m->private; - struct ftrace_event_call *call; + struct ftrace_event_file *file = v; + struct trace_array *tr = m->private; (*pos)++; - retry: - if (list == &ftrace_events) - return NULL; - - call = list_entry(list, struct ftrace_event_call, list); - - if (!call->enabled) { - list = list->next; - goto retry; + list_for_each_entry_continue(file, &tr->events, list) { + if (file->flags & FTRACE_EVENT_FL_ENABLED) + return file; } - m->private = list->next; - - return call; + return NULL; } static void *s_start(struct seq_file *m, loff_t *pos) { - struct ftrace_event_call *call = NULL; + struct ftrace_event_file *file; + struct trace_array *tr = m->private; loff_t l; mutex_lock(&event_mutex); - m->private = ftrace_events.next; + file = list_entry(&tr->events, struct ftrace_event_file, list); for (l = 0; l <= *pos; ) { - call = s_next(m, NULL, &l); - if (!call) + file = s_next(m, file, &l); + if (!file) break; } - return call; + return file; } static int t_show(struct seq_file *m, void *v) { - struct ftrace_event_call *call = v; + struct ftrace_event_file *file = v; + struct ftrace_event_call *call = file->event_call; - if (strcmp(call->system, TRACE_SYSTEM) != 0) - seq_printf(m, "%s:", call->system); - seq_printf(m, "%s\n", call->name); + if (strcmp(call->class->system, TRACE_SYSTEM) != 0) + seq_printf(m, "%s:", call->class->system); + seq_printf(m, "%s\n", ftrace_event_name(call)); return 0; } @@ -370,53 +716,46 @@ static void t_stop(struct seq_file *m, void *p) mutex_unlock(&event_mutex); } -static int -ftrace_event_seq_open(struct inode *inode, struct file *file) -{ - const struct seq_operations *seq_ops; - - if ((file->f_mode & FMODE_WRITE) && - !(file->f_flags & O_APPEND)) - ftrace_clear_events(); - - seq_ops = inode->i_private; - return seq_open(file, seq_ops); -} - static ssize_t event_enable_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { - struct ftrace_event_call *call = filp->private_data; - char *buf; + struct ftrace_event_file *file; + unsigned long flags; + char buf[4] = "0"; - if (call->enabled) - buf = "1\n"; - else - buf = "0\n"; + mutex_lock(&event_mutex); + file = event_file_data(filp); + if (likely(file)) + flags = file->flags; + mutex_unlock(&event_mutex); + + if (!file) + return -ENODEV; + + if (flags & FTRACE_EVENT_FL_ENABLED && + !(flags & FTRACE_EVENT_FL_SOFT_DISABLED)) + strcpy(buf, "1"); + + if (flags & FTRACE_EVENT_FL_SOFT_DISABLED || + flags & FTRACE_EVENT_FL_SOFT_MODE) + strcat(buf, "*"); - return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); + strcat(buf, "\n"); + + return simple_read_from_buffer(ubuf, cnt, ppos, buf, strlen(buf)); } static ssize_t event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { - struct ftrace_event_call *call = filp->private_data; - char buf[64]; + struct ftrace_event_file *file; unsigned long val; int ret; - if (cnt >= sizeof(buf)) - return -EINVAL; - - if (copy_from_user(&buf, ubuf, cnt)) - return -EFAULT; - - buf[cnt] = 0; - - ret = strict_strtoul(buf, 10, &val); - if (ret < 0) + ret = kstrtoul_from_user(ubuf, cnt, 10, &val); + if (ret) return ret; ret = tracing_update_buffers(); @@ -426,8 +765,11 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, switch (val) { case 0: case 1: + ret = -ENODEV; mutex_lock(&event_mutex); - ftrace_event_enable_disable(call, val); + file = event_file_data(filp); + if (likely(file)) + ret = ftrace_event_enable_disable(file, val); mutex_unlock(&event_mutex); break; @@ -437,7 +779,7 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, *ppos += cnt; - return cnt; + return ret ? ret : cnt; } static ssize_t @@ -445,18 +787,22 @@ system_enable_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { const char set_to_char[4] = { '?', '0', '1', 'X' }; - const char *system = filp->private_data; + struct ftrace_subsystem_dir *dir = filp->private_data; + struct event_subsystem *system = dir->subsystem; struct ftrace_event_call *call; + struct ftrace_event_file *file; + struct trace_array *tr = dir->tr; char buf[2]; int set = 0; int ret; mutex_lock(&event_mutex); - list_for_each_entry(call, &ftrace_events, list) { - if (!call->name || !call->regfunc) + list_for_each_entry(file, &tr->events, list) { + call = file->event_call; + if (!ftrace_event_name(call) || !call->class || !call->class->reg) continue; - if (system && strcmp(call->system, system) != 0) + if (system && strcmp(call->class->system, system->name) != 0) continue; /* @@ -464,7 +810,7 @@ system_enable_read(struct file *filp, char __user *ubuf, size_t cnt, * or if all events or cleared, or if we have * a mixture. */ - set |= (1 << !!call->enabled); + set |= (1 << !!(file->flags & FTRACE_EVENT_FL_ENABLED)); /* * If we have a mixture, no need to look further. @@ -486,21 +832,14 @@ static ssize_t system_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { - const char *system = filp->private_data; + struct ftrace_subsystem_dir *dir = filp->private_data; + struct event_subsystem *system = dir->subsystem; + const char *name = NULL; unsigned long val; - char buf[64]; ssize_t ret; - if (cnt >= sizeof(buf)) - return -EINVAL; - - if (copy_from_user(&buf, ubuf, cnt)) - return -EFAULT; - - buf[cnt] = 0; - - ret = strict_strtoul(buf, 10, &val); - if (ret < 0) + ret = kstrtoul_from_user(ubuf, cnt, 10, &val); + if (ret) return ret; ret = tracing_update_buffers(); @@ -510,7 +849,14 @@ system_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, if (val != 0 && val != 1) return -EINVAL; - ret = __ftrace_set_clr_event(NULL, system, NULL, val); + /* + * Opening of "enable" adds a ref count to system, + * so the name is safe to use. + */ + if (system) + name = system->name; + + ret = __ftrace_set_clr_event(dir->tr, NULL, name, NULL, val); if (ret) goto out; @@ -522,118 +868,181 @@ out: return ret; } -extern char *__bad_type_size(void); - -#undef FIELD -#define FIELD(type, name) \ - sizeof(type) != sizeof(field.name) ? __bad_type_size() : \ - #type, "common_" #name, offsetof(typeof(field), name), \ - sizeof(field.name) +enum { + FORMAT_HEADER = 1, + FORMAT_FIELD_SEPERATOR = 2, + FORMAT_PRINTFMT = 3, +}; -static int trace_write_header(struct trace_seq *s) +static void *f_next(struct seq_file *m, void *v, loff_t *pos) { - struct trace_entry field; + struct ftrace_event_call *call = event_file_data(m->private); + struct list_head *common_head = &ftrace_common_fields; + struct list_head *head = trace_get_fields(call); + struct list_head *node = v; + + (*pos)++; + + switch ((unsigned long)v) { + case FORMAT_HEADER: + node = common_head; + break; + + case FORMAT_FIELD_SEPERATOR: + node = head; + break; + + case FORMAT_PRINTFMT: + /* all done */ + return NULL; + } - /* struct trace_entry */ - return trace_seq_printf(s, - "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n" - "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n" - "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n" - "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n" - "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n" - "\n", - FIELD(unsigned short, type), - FIELD(unsigned char, flags), - FIELD(unsigned char, preempt_count), - FIELD(int, pid), - FIELD(int, tgid)); + node = node->prev; + if (node == common_head) + return (void *)FORMAT_FIELD_SEPERATOR; + else if (node == head) + return (void *)FORMAT_PRINTFMT; + else + return node; } -static ssize_t -event_format_read(struct file *filp, char __user *ubuf, size_t cnt, - loff_t *ppos) +static int f_show(struct seq_file *m, void *v) { - struct ftrace_event_call *call = filp->private_data; - struct trace_seq *s; - char *buf; - int r; + struct ftrace_event_call *call = event_file_data(m->private); + struct ftrace_event_field *field; + const char *array_descriptor; - if (*ppos) + switch ((unsigned long)v) { + case FORMAT_HEADER: + seq_printf(m, "name: %s\n", ftrace_event_name(call)); + seq_printf(m, "ID: %d\n", call->event.type); + seq_printf(m, "format:\n"); return 0; - s = kmalloc(sizeof(*s), GFP_KERNEL); - if (!s) - return -ENOMEM; + case FORMAT_FIELD_SEPERATOR: + seq_putc(m, '\n'); + return 0; - trace_seq_init(s); + case FORMAT_PRINTFMT: + seq_printf(m, "\nprint fmt: %s\n", + call->print_fmt); + return 0; + } - /* If any of the first writes fail, so will the show_format. */ + field = list_entry(v, struct ftrace_event_field, link); + /* + * Smartly shows the array type(except dynamic array). + * Normal: + * field:TYPE VAR + * If TYPE := TYPE[LEN], it is shown: + * field:TYPE VAR[LEN] + */ + array_descriptor = strchr(field->type, '['); - trace_seq_printf(s, "name: %s\n", call->name); - trace_seq_printf(s, "ID: %d\n", call->id); - trace_seq_printf(s, "format:\n"); - trace_write_header(s); + if (!strncmp(field->type, "__data_loc", 10)) + array_descriptor = NULL; - r = call->show_format(s); - if (!r) { - /* - * ug! The format output is bigger than a PAGE!! - */ - buf = "FORMAT TOO BIG\n"; - r = simple_read_from_buffer(ubuf, cnt, ppos, - buf, strlen(buf)); - goto out; - } + if (!array_descriptor) + seq_printf(m, "\tfield:%s %s;\toffset:%u;\tsize:%u;\tsigned:%d;\n", + field->type, field->name, field->offset, + field->size, !!field->is_signed); + else + seq_printf(m, "\tfield:%.*s %s%s;\toffset:%u;\tsize:%u;\tsigned:%d;\n", + (int)(array_descriptor - field->type), + field->type, field->name, + array_descriptor, field->offset, + field->size, !!field->is_signed); - r = simple_read_from_buffer(ubuf, cnt, ppos, - s->buffer, s->len); - out: - kfree(s); - return r; + return 0; +} + +static void *f_start(struct seq_file *m, loff_t *pos) +{ + void *p = (void *)FORMAT_HEADER; + loff_t l = 0; + + /* ->stop() is called even if ->start() fails */ + mutex_lock(&event_mutex); + if (!event_file_data(m->private)) + return ERR_PTR(-ENODEV); + + while (l < *pos && p) + p = f_next(m, p, &l); + + return p; +} + +static void f_stop(struct seq_file *m, void *p) +{ + mutex_unlock(&event_mutex); +} + +static const struct seq_operations trace_format_seq_ops = { + .start = f_start, + .next = f_next, + .stop = f_stop, + .show = f_show, +}; + +static int trace_format_open(struct inode *inode, struct file *file) +{ + struct seq_file *m; + int ret; + + ret = seq_open(file, &trace_format_seq_ops); + if (ret < 0) + return ret; + + m = file->private_data; + m->private = file; + + return 0; } static ssize_t event_id_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { - struct ftrace_event_call *call = filp->private_data; - struct trace_seq *s; - int r; + int id = (long)event_file_data(filp); + char buf[32]; + int len; if (*ppos) return 0; - s = kmalloc(sizeof(*s), GFP_KERNEL); - if (!s) - return -ENOMEM; + if (unlikely(!id)) + return -ENODEV; - trace_seq_init(s); - trace_seq_printf(s, "%d\n", call->id); + len = sprintf(buf, "%d\n", id); - r = simple_read_from_buffer(ubuf, cnt, ppos, - s->buffer, s->len); - kfree(s); - return r; + return simple_read_from_buffer(ubuf, cnt, ppos, buf, len); } static ssize_t event_filter_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { - struct ftrace_event_call *call = filp->private_data; + struct ftrace_event_file *file; struct trace_seq *s; - int r; + int r = -ENODEV; if (*ppos) return 0; s = kmalloc(sizeof(*s), GFP_KERNEL); + if (!s) return -ENOMEM; trace_seq_init(s); - print_event_filter(call, s); - r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len); + mutex_lock(&event_mutex); + file = event_file_data(filp); + if (file) + print_event_filter(file, s); + mutex_unlock(&event_mutex); + + if (file) + r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len); kfree(s); @@ -644,9 +1053,9 @@ static ssize_t event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { - struct ftrace_event_call *call = filp->private_data; + struct ftrace_event_file *file; char *buf; - int err; + int err = -ENODEV; if (cnt >= PAGE_SIZE) return -EINVAL; @@ -661,7 +1070,12 @@ event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, } buf[cnt] = '\0'; - err = apply_event_filter(call, buf); + mutex_lock(&event_mutex); + file = event_file_data(filp); + if (file) + err = apply_event_filter(file, buf); + mutex_unlock(&event_mutex); + free_page((unsigned long) buf); if (err < 0) return err; @@ -671,11 +1085,116 @@ event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, return cnt; } +static LIST_HEAD(event_subsystems); + +static int subsystem_open(struct inode *inode, struct file *filp) +{ + struct event_subsystem *system = NULL; + struct ftrace_subsystem_dir *dir = NULL; /* Initialize for gcc */ + struct trace_array *tr; + int ret; + + if (tracing_is_disabled()) + return -ENODEV; + + /* Make sure the system still exists */ + mutex_lock(&trace_types_lock); + mutex_lock(&event_mutex); + list_for_each_entry(tr, &ftrace_trace_arrays, list) { + list_for_each_entry(dir, &tr->systems, list) { + if (dir == inode->i_private) { + /* Don't open systems with no events */ + if (dir->nr_events) { + __get_system_dir(dir); + system = dir->subsystem; + } + goto exit_loop; + } + } + } + exit_loop: + mutex_unlock(&event_mutex); + mutex_unlock(&trace_types_lock); + + if (!system) + return -ENODEV; + + /* Some versions of gcc think dir can be uninitialized here */ + WARN_ON(!dir); + + /* Still need to increment the ref count of the system */ + if (trace_array_get(tr) < 0) { + put_system(dir); + return -ENODEV; + } + + ret = tracing_open_generic(inode, filp); + if (ret < 0) { + trace_array_put(tr); + put_system(dir); + } + + return ret; +} + +static int system_tr_open(struct inode *inode, struct file *filp) +{ + struct ftrace_subsystem_dir *dir; + struct trace_array *tr = inode->i_private; + int ret; + + if (tracing_is_disabled()) + return -ENODEV; + + if (trace_array_get(tr) < 0) + return -ENODEV; + + /* Make a temporary dir that has no system but points to tr */ + dir = kzalloc(sizeof(*dir), GFP_KERNEL); + if (!dir) { + trace_array_put(tr); + return -ENOMEM; + } + + dir->tr = tr; + + ret = tracing_open_generic(inode, filp); + if (ret < 0) { + trace_array_put(tr); + kfree(dir); + return ret; + } + + filp->private_data = dir; + + return 0; +} + +static int subsystem_release(struct inode *inode, struct file *file) +{ + struct ftrace_subsystem_dir *dir = file->private_data; + + trace_array_put(dir->tr); + + /* + * If dir->subsystem is NULL, then this is a temporary + * descriptor that was made for a trace_array to enable + * all subsystems. + */ + if (dir->subsystem) + put_system(dir); + else + kfree(dir); + + return 0; +} + static ssize_t subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { - struct event_subsystem *system = filp->private_data; + struct ftrace_subsystem_dir *dir = filp->private_data; + struct event_subsystem *system = dir->subsystem; struct trace_seq *s; int r; @@ -700,7 +1219,7 @@ static ssize_t subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { - struct event_subsystem *system = filp->private_data; + struct ftrace_subsystem_dir *dir = filp->private_data; char *buf; int err; @@ -717,7 +1236,7 @@ subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, } buf[cnt] = '\0'; - err = apply_subsystem_event_filter(system, buf); + err = apply_subsystem_event_filter(dir, buf); free_page((unsigned long) buf); if (err < 0) return err; @@ -751,6 +1270,10 @@ show_header(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) return r; } +static int ftrace_event_avail_open(struct inode *inode, struct file *file); +static int ftrace_event_set_open(struct inode *inode, struct file *file); +static int ftrace_event_release(struct inode *inode, struct file *file); + static const struct seq_operations show_event_seq_ops = { .start = t_start, .next = t_next, @@ -766,337 +1289,573 @@ static const struct seq_operations show_set_event_seq_ops = { }; static const struct file_operations ftrace_avail_fops = { - .open = ftrace_event_seq_open, + .open = ftrace_event_avail_open, .read = seq_read, .llseek = seq_lseek, .release = seq_release, }; static const struct file_operations ftrace_set_event_fops = { - .open = ftrace_event_seq_open, + .open = ftrace_event_set_open, .read = seq_read, .write = ftrace_event_write, .llseek = seq_lseek, - .release = seq_release, + .release = ftrace_event_release, }; static const struct file_operations ftrace_enable_fops = { .open = tracing_open_generic, .read = event_enable_read, .write = event_enable_write, + .llseek = default_llseek, }; static const struct file_operations ftrace_event_format_fops = { - .open = tracing_open_generic, - .read = event_format_read, + .open = trace_format_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, }; static const struct file_operations ftrace_event_id_fops = { - .open = tracing_open_generic, .read = event_id_read, + .llseek = default_llseek, }; static const struct file_operations ftrace_event_filter_fops = { .open = tracing_open_generic, .read = event_filter_read, .write = event_filter_write, + .llseek = default_llseek, }; static const struct file_operations ftrace_subsystem_filter_fops = { - .open = tracing_open_generic, + .open = subsystem_open, .read = subsystem_filter_read, .write = subsystem_filter_write, + .llseek = default_llseek, + .release = subsystem_release, }; static const struct file_operations ftrace_system_enable_fops = { - .open = tracing_open_generic, + .open = subsystem_open, .read = system_enable_read, .write = system_enable_write, + .llseek = default_llseek, + .release = subsystem_release, +}; + +static const struct file_operations ftrace_tr_enable_fops = { + .open = system_tr_open, + .read = system_enable_read, + .write = system_enable_write, + .llseek = default_llseek, + .release = subsystem_release, }; static const struct file_operations ftrace_show_header_fops = { .open = tracing_open_generic, .read = show_header, + .llseek = default_llseek, }; -static struct dentry *event_trace_events_dir(void) +static int +ftrace_event_open(struct inode *inode, struct file *file, + const struct seq_operations *seq_ops) { - static struct dentry *d_tracer; - static struct dentry *d_events; + struct seq_file *m; + int ret; - if (d_events) - return d_events; + ret = seq_open(file, seq_ops); + if (ret < 0) + return ret; + m = file->private_data; + /* copy tr over to seq ops */ + m->private = inode->i_private; - d_tracer = tracing_init_dentry(); - if (!d_tracer) - return NULL; + return ret; +} - d_events = debugfs_create_dir("events", d_tracer); - if (!d_events) - pr_warning("Could not create debugfs " - "'events' directory\n"); +static int ftrace_event_release(struct inode *inode, struct file *file) +{ + struct trace_array *tr = inode->i_private; + + trace_array_put(tr); - return d_events; + return seq_release(inode, file); } -static LIST_HEAD(event_subsystems); +static int +ftrace_event_avail_open(struct inode *inode, struct file *file) +{ + const struct seq_operations *seq_ops = &show_event_seq_ops; + + return ftrace_event_open(inode, file, seq_ops); +} + +static int +ftrace_event_set_open(struct inode *inode, struct file *file) +{ + const struct seq_operations *seq_ops = &show_set_event_seq_ops; + struct trace_array *tr = inode->i_private; + int ret; + + if (trace_array_get(tr) < 0) + return -ENODEV; + + if ((file->f_mode & FMODE_WRITE) && + (file->f_flags & O_TRUNC)) + ftrace_clear_events(tr); + + ret = ftrace_event_open(inode, file, seq_ops); + if (ret < 0) + trace_array_put(tr); + return ret; +} + +static struct event_subsystem * +create_new_subsystem(const char *name) +{ + struct event_subsystem *system; + + /* need to create new entry */ + system = kmalloc(sizeof(*system), GFP_KERNEL); + if (!system) + return NULL; + + system->ref_count = 1; + + /* Only allocate if dynamic (kprobes and modules) */ + if (!core_kernel_data((unsigned long)name)) { + system->ref_count |= SYSTEM_FL_FREE_NAME; + system->name = kstrdup(name, GFP_KERNEL); + if (!system->name) + goto out_free; + } else + system->name = name; + + system->filter = NULL; + + system->filter = kzalloc(sizeof(struct event_filter), GFP_KERNEL); + if (!system->filter) + goto out_free; + + list_add(&system->list, &event_subsystems); + + return system; + + out_free: + if (system->ref_count & SYSTEM_FL_FREE_NAME) + kfree(system->name); + kfree(system); + return NULL; +} static struct dentry * -event_subsystem_dir(const char *name, struct dentry *d_events) +event_subsystem_dir(struct trace_array *tr, const char *name, + struct ftrace_event_file *file, struct dentry *parent) { + struct ftrace_subsystem_dir *dir; struct event_subsystem *system; struct dentry *entry; /* First see if we did not already create this dir */ + list_for_each_entry(dir, &tr->systems, list) { + system = dir->subsystem; + if (strcmp(system->name, name) == 0) { + dir->nr_events++; + file->system = dir; + return dir->entry; + } + } + + /* Now see if the system itself exists. */ list_for_each_entry(system, &event_subsystems, list) { if (strcmp(system->name, name) == 0) - return system->entry; + break; } + /* Reset system variable when not found */ + if (&system->list == &event_subsystems) + system = NULL; - /* need to create new entry */ - system = kmalloc(sizeof(*system), GFP_KERNEL); - if (!system) { - pr_warning("No memory to create event subsystem %s\n", - name); - return d_events; - } + dir = kmalloc(sizeof(*dir), GFP_KERNEL); + if (!dir) + goto out_fail; - system->entry = debugfs_create_dir(name, d_events); - if (!system->entry) { - pr_warning("Could not create event subsystem %s\n", - name); - kfree(system); - return d_events; - } + if (!system) { + system = create_new_subsystem(name); + if (!system) + goto out_free; + } else + __get_system(system); - system->name = kstrdup(name, GFP_KERNEL); - if (!system->name) { - debugfs_remove(system->entry); - kfree(system); - return d_events; + dir->entry = debugfs_create_dir(name, parent); + if (!dir->entry) { + pr_warning("Failed to create system directory %s\n", name); + __put_system(system); + goto out_free; } - list_add(&system->list, &event_subsystems); + dir->tr = tr; + dir->ref_count = 1; + dir->nr_events = 1; + dir->subsystem = system; + file->system = dir; - system->filter = NULL; - - system->filter = kzalloc(sizeof(struct event_filter), GFP_KERNEL); - if (!system->filter) { - pr_warning("Could not allocate filter for subsystem " - "'%s'\n", name); - return system->entry; - } - - entry = debugfs_create_file("filter", 0644, system->entry, system, + entry = debugfs_create_file("filter", 0644, dir->entry, dir, &ftrace_subsystem_filter_fops); if (!entry) { kfree(system->filter); system->filter = NULL; - pr_warning("Could not create debugfs " - "'%s/filter' entry\n", name); + pr_warning("Could not create debugfs '%s/filter' entry\n", name); } - entry = trace_create_file("enable", 0644, system->entry, - (void *)system->name, - &ftrace_system_enable_fops); + trace_create_file("enable", 0644, dir->entry, dir, + &ftrace_system_enable_fops); + + list_add(&dir->list, &tr->systems); - return system->entry; + return dir->entry; + + out_free: + kfree(dir); + out_fail: + /* Only print this message if failed on memory allocation */ + if (!dir || !system) + pr_warning("No memory to create event subsystem %s\n", + name); + return NULL; } static int -event_create_dir(struct ftrace_event_call *call, struct dentry *d_events, - const struct file_operations *id, - const struct file_operations *enable, - const struct file_operations *filter, - const struct file_operations *format) +event_create_dir(struct dentry *parent, struct ftrace_event_file *file) { - struct dentry *entry; + struct ftrace_event_call *call = file->event_call; + struct trace_array *tr = file->tr; + struct list_head *head; + struct dentry *d_events; + const char *name; int ret; /* * If the trace point header did not define TRACE_SYSTEM * then the system would be called "TRACE_SYSTEM". */ - if (strcmp(call->system, TRACE_SYSTEM) != 0) - d_events = event_subsystem_dir(call->system, d_events); + if (strcmp(call->class->system, TRACE_SYSTEM) != 0) { + d_events = event_subsystem_dir(tr, call->class->system, file, parent); + if (!d_events) + return -ENOMEM; + } else + d_events = parent; + + name = ftrace_event_name(call); + file->dir = debugfs_create_dir(name, d_events); + if (!file->dir) { + pr_warning("Could not create debugfs '%s' directory\n", + name); + return -1; + } + + if (call->class->reg && !(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) + trace_create_file("enable", 0644, file->dir, file, + &ftrace_enable_fops); - if (call->raw_init) { - ret = call->raw_init(); +#ifdef CONFIG_PERF_EVENTS + if (call->event.type && call->class->reg) + trace_create_file("id", 0444, file->dir, + (void *)(long)call->event.type, + &ftrace_event_id_fops); +#endif + + /* + * Other events may have the same class. Only update + * the fields if they are not already defined. + */ + head = trace_get_fields(call); + if (list_empty(head)) { + ret = call->class->define_fields(call); if (ret < 0) { pr_warning("Could not initialize trace point" - " events/%s\n", call->name); - return ret; + " events/%s\n", name); + return -1; } } + trace_create_file("filter", 0644, file->dir, file, + &ftrace_event_filter_fops); - call->dir = debugfs_create_dir(call->name, d_events); - if (!call->dir) { - pr_warning("Could not create debugfs " - "'%s' directory\n", call->name); - return -1; - } + trace_create_file("trigger", 0644, file->dir, file, + &event_trigger_fops); - if (call->regfunc) - entry = trace_create_file("enable", 0644, call->dir, call, - enable); + trace_create_file("format", 0444, file->dir, call, + &ftrace_event_format_fops); - if (call->id) - entry = trace_create_file("id", 0444, call->dir, call, - id); + return 0; +} - if (call->define_fields) { - ret = call->define_fields(); - if (ret < 0) { - pr_warning("Could not initialize trace point" - " events/%s\n", call->name); - return ret; - } - entry = trace_create_file("filter", 0644, call->dir, call, - filter); +static void remove_event_from_tracers(struct ftrace_event_call *call) +{ + struct ftrace_event_file *file; + struct trace_array *tr; + + do_for_each_event_file_safe(tr, file) { + if (file->event_call != call) + continue; + + remove_event_file_dir(file); + /* + * The do_for_each_event_file_safe() is + * a double loop. After finding the call for this + * trace_array, we use break to jump to the next + * trace_array. + */ + break; + } while_for_each_event_file(); +} + +static void event_remove(struct ftrace_event_call *call) +{ + struct trace_array *tr; + struct ftrace_event_file *file; + + do_for_each_event_file(tr, file) { + if (file->event_call != call) + continue; + ftrace_event_enable_disable(file, 0); + destroy_preds(file); + /* + * The do_for_each_event_file() is + * a double loop. After finding the call for this + * trace_array, we use break to jump to the next + * trace_array. + */ + break; + } while_for_each_event_file(); + + if (call->event.funcs) + __unregister_ftrace_event(&call->event); + remove_event_from_tracers(call); + list_del(&call->list); +} + +static int event_init(struct ftrace_event_call *call) +{ + int ret = 0; + const char *name; + + name = ftrace_event_name(call); + if (WARN_ON(!name)) + return -EINVAL; + + if (call->class->raw_init) { + ret = call->class->raw_init(call); + if (ret < 0 && ret != -ENOSYS) + pr_warn("Could not initialize trace events/%s\n", + name); } - /* A trace may not want to export its format */ - if (!call->show_format) - return 0; + return ret; +} - entry = trace_create_file("format", 0444, call->dir, call, - format); +static int +__register_event(struct ftrace_event_call *call, struct module *mod) +{ + int ret; + + ret = event_init(call); + if (ret < 0) + return ret; + + list_add(&call->list, &ftrace_events); + call->mod = mod; return 0; } -#define for_each_event(event, start, end) \ - for (event = start; \ - (unsigned long)event < (unsigned long)end; \ - event++) +static struct ftrace_event_file * +trace_create_new_event(struct ftrace_event_call *call, + struct trace_array *tr) +{ + struct ftrace_event_file *file; -#ifdef CONFIG_MODULES + file = kmem_cache_alloc(file_cachep, GFP_TRACE); + if (!file) + return NULL; + + file->event_call = call; + file->tr = tr; + atomic_set(&file->sm_ref, 0); + atomic_set(&file->tm_ref, 0); + INIT_LIST_HEAD(&file->triggers); + list_add(&file->list, &tr->events); + + return file; +} + +/* Add an event to a trace directory */ +static int +__trace_add_new_event(struct ftrace_event_call *call, struct trace_array *tr) +{ + struct ftrace_event_file *file; -static LIST_HEAD(ftrace_module_file_list); + file = trace_create_new_event(call, tr); + if (!file) + return -ENOMEM; + + return event_create_dir(tr->event_dir, file); +} /* - * Modules must own their file_operations to keep up with - * reference counting. + * Just create a decriptor for early init. A descriptor is required + * for enabling events at boot. We want to enable events before + * the filesystem is initialized. */ -struct ftrace_module_file_ops { - struct list_head list; - struct module *mod; - struct file_operations id; - struct file_operations enable; - struct file_operations format; - struct file_operations filter; -}; +static __init int +__trace_early_add_new_event(struct ftrace_event_call *call, + struct trace_array *tr) +{ + struct ftrace_event_file *file; -static struct ftrace_module_file_ops * -trace_create_file_ops(struct module *mod) + file = trace_create_new_event(call, tr); + if (!file) + return -ENOMEM; + + return 0; +} + +struct ftrace_module_file_ops; +static void __add_event_to_tracers(struct ftrace_event_call *call); + +/* Add an additional event_call dynamically */ +int trace_add_event_call(struct ftrace_event_call *call) { - struct ftrace_module_file_ops *file_ops; + int ret; + mutex_lock(&trace_types_lock); + mutex_lock(&event_mutex); - /* - * This is a bit of a PITA. To allow for correct reference - * counting, modules must "own" their file_operations. - * To do this, we allocate the file operations that will be - * used in the event directory. - */ + ret = __register_event(call, NULL); + if (ret >= 0) + __add_event_to_tracers(call); - file_ops = kmalloc(sizeof(*file_ops), GFP_KERNEL); - if (!file_ops) - return NULL; + mutex_unlock(&event_mutex); + mutex_unlock(&trace_types_lock); + return ret; +} - file_ops->mod = mod; +/* + * Must be called under locking of trace_types_lock, event_mutex and + * trace_event_sem. + */ +static void __trace_remove_event_call(struct ftrace_event_call *call) +{ + event_remove(call); + trace_destroy_fields(call); + destroy_call_preds(call); +} - file_ops->id = ftrace_event_id_fops; - file_ops->id.owner = mod; +static int probe_remove_event_call(struct ftrace_event_call *call) +{ + struct trace_array *tr; + struct ftrace_event_file *file; - file_ops->enable = ftrace_enable_fops; - file_ops->enable.owner = mod; +#ifdef CONFIG_PERF_EVENTS + if (call->perf_refcount) + return -EBUSY; +#endif + do_for_each_event_file(tr, file) { + if (file->event_call != call) + continue; + /* + * We can't rely on ftrace_event_enable_disable(enable => 0) + * we are going to do, FTRACE_EVENT_FL_SOFT_MODE can suppress + * TRACE_REG_UNREGISTER. + */ + if (file->flags & FTRACE_EVENT_FL_ENABLED) + return -EBUSY; + /* + * The do_for_each_event_file_safe() is + * a double loop. After finding the call for this + * trace_array, we use break to jump to the next + * trace_array. + */ + break; + } while_for_each_event_file(); - file_ops->filter = ftrace_event_filter_fops; - file_ops->filter.owner = mod; + __trace_remove_event_call(call); - file_ops->format = ftrace_event_format_fops; - file_ops->format.owner = mod; + return 0; +} - list_add(&file_ops->list, &ftrace_module_file_list); +/* Remove an event_call */ +int trace_remove_event_call(struct ftrace_event_call *call) +{ + int ret; - return file_ops; + mutex_lock(&trace_types_lock); + mutex_lock(&event_mutex); + down_write(&trace_event_sem); + ret = probe_remove_event_call(call); + up_write(&trace_event_sem); + mutex_unlock(&event_mutex); + mutex_unlock(&trace_types_lock); + + return ret; } +#define for_each_event(event, start, end) \ + for (event = start; \ + (unsigned long)event < (unsigned long)end; \ + event++) + +#ifdef CONFIG_MODULES + static void trace_module_add_events(struct module *mod) { - struct ftrace_module_file_ops *file_ops = NULL; - struct ftrace_event_call *call, *start, *end; - struct dentry *d_events; - - start = mod->trace_events; - end = mod->trace_events + mod->num_trace_events; + struct ftrace_event_call **call, **start, **end; - if (start == end) + if (!mod->num_trace_events) return; - d_events = event_trace_events_dir(); - if (!d_events) + /* Don't add infrastructure for mods without tracepoints */ + if (trace_module_has_bad_taint(mod)) { + pr_err("%s: module has bad taint, not creating trace events\n", + mod->name); return; + } - for_each_event(call, start, end) { - /* The linker may leave blanks */ - if (!call->name) - continue; + start = mod->trace_events; + end = mod->trace_events + mod->num_trace_events; - /* - * This module has events, create file ops for this module - * if not already done. - */ - if (!file_ops) { - file_ops = trace_create_file_ops(mod); - if (!file_ops) - return; - } - call->mod = mod; - list_add(&call->list, &ftrace_events); - event_create_dir(call, d_events, - &file_ops->id, &file_ops->enable, - &file_ops->filter, &file_ops->format); + for_each_event(call, start, end) { + __register_event(*call, mod); + __add_event_to_tracers(*call); } } static void trace_module_remove_events(struct module *mod) { - struct ftrace_module_file_ops *file_ops; struct ftrace_event_call *call, *p; - bool found = false; + bool clear_trace = false; - down_write(&trace_event_mutex); + down_write(&trace_event_sem); list_for_each_entry_safe(call, p, &ftrace_events, list) { if (call->mod == mod) { - found = true; - ftrace_event_enable_disable(call, 0); - if (call->event) - __unregister_ftrace_event(call->event); - debugfs_remove_recursive(call->dir); - list_del(&call->list); - trace_destroy_fields(call); - destroy_preds(call); + if (call->flags & TRACE_EVENT_FL_WAS_ENABLED) + clear_trace = true; + __trace_remove_event_call(call); } } - - /* Now free the file_operations */ - list_for_each_entry(file_ops, &ftrace_module_file_list, list) { - if (file_ops->mod == mod) - break; - } - if (&file_ops->list != &ftrace_module_file_list) { - list_del(&file_ops->list); - kfree(file_ops); - } + up_write(&trace_event_sem); /* * It is safest to reset the ring buffer if the module being unloaded - * registered any events. + * registered any events that were used. The only worry is if + * a new module gets loaded, and takes on the same id as the events + * of this module. When printing out the buffer, traced events left + * over from this module may be passed to the new module events and + * unexpected results may occur. */ - if (found) - tracing_reset_current_online_cpus(); - up_write(&trace_event_mutex); + if (clear_trace) + tracing_reset_all_online_cpus(); } static int trace_module_notify(struct notifier_block *self, @@ -1104,6 +1863,7 @@ static int trace_module_notify(struct notifier_block *self, { struct module *mod = data; + mutex_lock(&trace_types_lock); mutex_lock(&event_mutex); switch (val) { case MODULE_STATE_COMING: @@ -1114,54 +1874,421 @@ static int trace_module_notify(struct notifier_block *self, break; } mutex_unlock(&event_mutex); + mutex_unlock(&trace_types_lock); return 0; } -#else -static int trace_module_notify(struct notifier_block *self, - unsigned long val, void *data) + +static struct notifier_block trace_module_nb = { + .notifier_call = trace_module_notify, + .priority = 0, +}; +#endif /* CONFIG_MODULES */ + +/* Create a new event directory structure for a trace directory. */ +static void +__trace_add_event_dirs(struct trace_array *tr) { + struct ftrace_event_call *call; + int ret; + + list_for_each_entry(call, &ftrace_events, list) { + ret = __trace_add_new_event(call, tr); + if (ret < 0) + pr_warning("Could not create directory for event %s\n", + ftrace_event_name(call)); + } +} + +struct ftrace_event_file * +find_event_file(struct trace_array *tr, const char *system, const char *event) +{ + struct ftrace_event_file *file; + struct ftrace_event_call *call; + const char *name; + + list_for_each_entry(file, &tr->events, list) { + + call = file->event_call; + name = ftrace_event_name(call); + + if (!name || !call->class || !call->class->reg) + continue; + + if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) + continue; + + if (strcmp(event, name) == 0 && + strcmp(system, call->class->system) == 0) + return file; + } + return NULL; +} + +#ifdef CONFIG_DYNAMIC_FTRACE + +/* Avoid typos */ +#define ENABLE_EVENT_STR "enable_event" +#define DISABLE_EVENT_STR "disable_event" + +struct event_probe_data { + struct ftrace_event_file *file; + unsigned long count; + int ref; + bool enable; +}; + +static void +event_enable_probe(unsigned long ip, unsigned long parent_ip, void **_data) +{ + struct event_probe_data **pdata = (struct event_probe_data **)_data; + struct event_probe_data *data = *pdata; + + if (!data) + return; + + if (data->enable) + clear_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &data->file->flags); + else + set_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &data->file->flags); +} + +static void +event_enable_count_probe(unsigned long ip, unsigned long parent_ip, void **_data) +{ + struct event_probe_data **pdata = (struct event_probe_data **)_data; + struct event_probe_data *data = *pdata; + + if (!data) + return; + + if (!data->count) + return; + + /* Skip if the event is in a state we want to switch to */ + if (data->enable == !(data->file->flags & FTRACE_EVENT_FL_SOFT_DISABLED)) + return; + + if (data->count != -1) + (data->count)--; + + event_enable_probe(ip, parent_ip, _data); +} + +static int +event_enable_print(struct seq_file *m, unsigned long ip, + struct ftrace_probe_ops *ops, void *_data) +{ + struct event_probe_data *data = _data; + + seq_printf(m, "%ps:", (void *)ip); + + seq_printf(m, "%s:%s:%s", + data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR, + data->file->event_call->class->system, + ftrace_event_name(data->file->event_call)); + + if (data->count == -1) + seq_printf(m, ":unlimited\n"); + else + seq_printf(m, ":count=%ld\n", data->count); + return 0; } -#endif /* CONFIG_MODULES */ -struct notifier_block trace_module_nb = { - .notifier_call = trace_module_notify, - .priority = 0, +static int +event_enable_init(struct ftrace_probe_ops *ops, unsigned long ip, + void **_data) +{ + struct event_probe_data **pdata = (struct event_probe_data **)_data; + struct event_probe_data *data = *pdata; + + data->ref++; + return 0; +} + +static void +event_enable_free(struct ftrace_probe_ops *ops, unsigned long ip, + void **_data) +{ + struct event_probe_data **pdata = (struct event_probe_data **)_data; + struct event_probe_data *data = *pdata; + + if (WARN_ON_ONCE(data->ref <= 0)) + return; + + data->ref--; + if (!data->ref) { + /* Remove the SOFT_MODE flag */ + __ftrace_event_enable_disable(data->file, 0, 1); + module_put(data->file->event_call->mod); + kfree(data); + } + *pdata = NULL; +} + +static struct ftrace_probe_ops event_enable_probe_ops = { + .func = event_enable_probe, + .print = event_enable_print, + .init = event_enable_init, + .free = event_enable_free, }; -extern struct ftrace_event_call __start_ftrace_events[]; -extern struct ftrace_event_call __stop_ftrace_events[]; +static struct ftrace_probe_ops event_enable_count_probe_ops = { + .func = event_enable_count_probe, + .print = event_enable_print, + .init = event_enable_init, + .free = event_enable_free, +}; -static __init int event_trace_init(void) +static struct ftrace_probe_ops event_disable_probe_ops = { + .func = event_enable_probe, + .print = event_enable_print, + .init = event_enable_init, + .free = event_enable_free, +}; + +static struct ftrace_probe_ops event_disable_count_probe_ops = { + .func = event_enable_count_probe, + .print = event_enable_print, + .init = event_enable_init, + .free = event_enable_free, +}; + +static int +event_enable_func(struct ftrace_hash *hash, + char *glob, char *cmd, char *param, int enabled) +{ + struct trace_array *tr = top_trace_array(); + struct ftrace_event_file *file; + struct ftrace_probe_ops *ops; + struct event_probe_data *data; + const char *system; + const char *event; + char *number; + bool enable; + int ret; + + if (!tr) + return -ENODEV; + + /* hash funcs only work with set_ftrace_filter */ + if (!enabled || !param) + return -EINVAL; + + system = strsep(¶m, ":"); + if (!param) + return -EINVAL; + + event = strsep(¶m, ":"); + + mutex_lock(&event_mutex); + + ret = -EINVAL; + file = find_event_file(tr, system, event); + if (!file) + goto out; + + enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; + + if (enable) + ops = param ? &event_enable_count_probe_ops : &event_enable_probe_ops; + else + ops = param ? &event_disable_count_probe_ops : &event_disable_probe_ops; + + if (glob[0] == '!') { + unregister_ftrace_function_probe_func(glob+1, ops); + ret = 0; + goto out; + } + + ret = -ENOMEM; + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + goto out; + + data->enable = enable; + data->count = -1; + data->file = file; + + if (!param) + goto out_reg; + + number = strsep(¶m, ":"); + + ret = -EINVAL; + if (!strlen(number)) + goto out_free; + + /* + * We use the callback data field (which is a pointer) + * as our counter. + */ + ret = kstrtoul(number, 0, &data->count); + if (ret) + goto out_free; + + out_reg: + /* Don't let event modules unload while probe registered */ + ret = try_module_get(file->event_call->mod); + if (!ret) { + ret = -EBUSY; + goto out_free; + } + + ret = __ftrace_event_enable_disable(file, 1, 1); + if (ret < 0) + goto out_put; + ret = register_ftrace_function_probe(glob, ops, data); + /* + * The above returns on success the # of functions enabled, + * but if it didn't find any functions it returns zero. + * Consider no functions a failure too. + */ + if (!ret) { + ret = -ENOENT; + goto out_disable; + } else if (ret < 0) + goto out_disable; + /* Just return zero, not the number of enabled functions */ + ret = 0; + out: + mutex_unlock(&event_mutex); + return ret; + + out_disable: + __ftrace_event_enable_disable(file, 0, 1); + out_put: + module_put(file->event_call->mod); + out_free: + kfree(data); + goto out; +} + +static struct ftrace_func_command event_enable_cmd = { + .name = ENABLE_EVENT_STR, + .func = event_enable_func, +}; + +static struct ftrace_func_command event_disable_cmd = { + .name = DISABLE_EVENT_STR, + .func = event_enable_func, +}; + +static __init int register_event_cmds(void) +{ + int ret; + + ret = register_ftrace_command(&event_enable_cmd); + if (WARN_ON(ret < 0)) + return ret; + ret = register_ftrace_command(&event_disable_cmd); + if (WARN_ON(ret < 0)) + unregister_ftrace_command(&event_enable_cmd); + return ret; +} +#else +static inline int register_event_cmds(void) { return 0; } +#endif /* CONFIG_DYNAMIC_FTRACE */ + +/* + * The top level array has already had its ftrace_event_file + * descriptors created in order to allow for early events to + * be recorded. This function is called after the debugfs has been + * initialized, and we now have to create the files associated + * to the events. + */ +static __init void +__trace_early_add_event_dirs(struct trace_array *tr) +{ + struct ftrace_event_file *file; + int ret; + + + list_for_each_entry(file, &tr->events, list) { + ret = event_create_dir(tr->event_dir, file); + if (ret < 0) + pr_warning("Could not create directory for event %s\n", + ftrace_event_name(file->event_call)); + } +} + +/* + * For early boot up, the top trace array requires to have + * a list of events that can be enabled. This must be done before + * the filesystem is set up in order to allow events to be traced + * early. + */ +static __init void +__trace_early_add_events(struct trace_array *tr) { struct ftrace_event_call *call; - struct dentry *d_tracer; - struct dentry *entry; - struct dentry *d_events; int ret; - d_tracer = tracing_init_dentry(); - if (!d_tracer) - return 0; + list_for_each_entry(call, &ftrace_events, list) { + /* Early boot up should not have any modules loaded */ + if (WARN_ON_ONCE(call->mod)) + continue; - entry = debugfs_create_file("available_events", 0444, d_tracer, - (void *)&show_event_seq_ops, - &ftrace_avail_fops); - if (!entry) - pr_warning("Could not create debugfs " - "'available_events' entry\n"); + ret = __trace_early_add_new_event(call, tr); + if (ret < 0) + pr_warning("Could not create early event %s\n", + ftrace_event_name(call)); + } +} - entry = debugfs_create_file("set_event", 0644, d_tracer, - (void *)&show_set_event_seq_ops, - &ftrace_set_event_fops); - if (!entry) - pr_warning("Could not create debugfs " - "'set_event' entry\n"); +/* Remove the event directory structure for a trace directory. */ +static void +__trace_remove_event_dirs(struct trace_array *tr) +{ + struct ftrace_event_file *file, *next; - d_events = event_trace_events_dir(); - if (!d_events) - return 0; + list_for_each_entry_safe(file, next, &tr->events, list) + remove_event_file_dir(file); +} + +static void __add_event_to_tracers(struct ftrace_event_call *call) +{ + struct trace_array *tr; + + list_for_each_entry(tr, &ftrace_trace_arrays, list) + __trace_add_new_event(call, tr); +} + +extern struct ftrace_event_call *__start_ftrace_events[]; +extern struct ftrace_event_call *__stop_ftrace_events[]; + +static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata; + +static __init int setup_trace_event(char *str) +{ + strlcpy(bootup_event_buf, str, COMMAND_LINE_SIZE); + ring_buffer_expanded = true; + tracing_selftest_disabled = true; + + return 1; +} +__setup("trace_event=", setup_trace_event); + +/* Expects to have event_mutex held when called */ +static int +create_event_toplevel_files(struct dentry *parent, struct trace_array *tr) +{ + struct dentry *d_events; + struct dentry *entry; + + entry = debugfs_create_file("set_event", 0644, parent, + tr, &ftrace_set_event_fops); + if (!entry) { + pr_warning("Could not create debugfs 'set_event' entry\n"); + return -ENOMEM; + } + + d_events = debugfs_create_dir("events", parent); + if (!d_events) { + pr_warning("Could not create debugfs 'events' directory\n"); + return -ENOMEM; + } /* ring buffer internal formats */ trace_create_file("header_page", 0444, d_events, @@ -1173,24 +2300,187 @@ static __init int event_trace_init(void) &ftrace_show_header_fops); trace_create_file("enable", 0644, d_events, - NULL, &ftrace_system_enable_fops); + tr, &ftrace_tr_enable_fops); + + tr->event_dir = d_events; - for_each_event(call, __start_ftrace_events, __stop_ftrace_events) { - /* The linker may leave blanks */ - if (!call->name) + return 0; +} + +/** + * event_trace_add_tracer - add a instance of a trace_array to events + * @parent: The parent dentry to place the files/directories for events in + * @tr: The trace array associated with these events + * + * When a new instance is created, it needs to set up its events + * directory, as well as other files associated with events. It also + * creates the event hierachry in the @parent/events directory. + * + * Returns 0 on success. + */ +int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr) +{ + int ret; + + mutex_lock(&event_mutex); + + ret = create_event_toplevel_files(parent, tr); + if (ret) + goto out_unlock; + + down_write(&trace_event_sem); + __trace_add_event_dirs(tr); + up_write(&trace_event_sem); + + out_unlock: + mutex_unlock(&event_mutex); + + return ret; +} + +/* + * The top trace array already had its file descriptors created. + * Now the files themselves need to be created. + */ +static __init int +early_event_add_tracer(struct dentry *parent, struct trace_array *tr) +{ + int ret; + + mutex_lock(&event_mutex); + + ret = create_event_toplevel_files(parent, tr); + if (ret) + goto out_unlock; + + down_write(&trace_event_sem); + __trace_early_add_event_dirs(tr); + up_write(&trace_event_sem); + + out_unlock: + mutex_unlock(&event_mutex); + + return ret; +} + +int event_trace_del_tracer(struct trace_array *tr) +{ + mutex_lock(&event_mutex); + + /* Disable any event triggers and associated soft-disabled events */ + clear_event_triggers(tr); + + /* Disable any running events */ + __ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0); + + /* Access to events are within rcu_read_lock_sched() */ + synchronize_sched(); + + down_write(&trace_event_sem); + __trace_remove_event_dirs(tr); + debugfs_remove_recursive(tr->event_dir); + up_write(&trace_event_sem); + + tr->event_dir = NULL; + + mutex_unlock(&event_mutex); + + return 0; +} + +static __init int event_trace_memsetup(void) +{ + field_cachep = KMEM_CACHE(ftrace_event_field, SLAB_PANIC); + file_cachep = KMEM_CACHE(ftrace_event_file, SLAB_PANIC); + return 0; +} + +static __init int event_trace_enable(void) +{ + struct trace_array *tr = top_trace_array(); + struct ftrace_event_call **iter, *call; + char *buf = bootup_event_buf; + char *token; + int ret; + + if (!tr) + return -ENODEV; + + for_each_event(iter, __start_ftrace_events, __stop_ftrace_events) { + + call = *iter; + ret = event_init(call); + if (!ret) + list_add(&call->list, &ftrace_events); + } + + /* + * We need the top trace array to have a working set of trace + * points at early init, before the debug files and directories + * are created. Create the file entries now, and attach them + * to the actual file dentries later. + */ + __trace_early_add_events(tr); + + while (true) { + token = strsep(&buf, ","); + + if (!token) + break; + if (!*token) continue; - list_add(&call->list, &ftrace_events); - event_create_dir(call, d_events, &ftrace_event_id_fops, - &ftrace_enable_fops, &ftrace_event_filter_fops, - &ftrace_event_format_fops); + + ret = ftrace_set_clr_event(tr, token, 1); + if (ret) + pr_warn("Failed to enable trace event: %s\n", token); } + trace_printk_start_comm(); + + register_event_cmds(); + + register_trigger_cmds(); + + return 0; +} + +static __init int event_trace_init(void) +{ + struct trace_array *tr; + struct dentry *d_tracer; + struct dentry *entry; + int ret; + + tr = top_trace_array(); + if (!tr) + return -ENODEV; + + d_tracer = tracing_init_dentry(); + if (!d_tracer) + return 0; + + entry = debugfs_create_file("available_events", 0444, d_tracer, + tr, &ftrace_avail_fops); + if (!entry) + pr_warning("Could not create debugfs " + "'available_events' entry\n"); + + if (trace_define_common_fields()) + pr_warning("tracing: Failed to allocate common fields"); + + ret = early_event_add_tracer(d_tracer, tr); + if (ret) + return ret; + +#ifdef CONFIG_MODULES ret = register_module_notifier(&trace_module_nb); if (ret) pr_warning("Failed to register trace events module notifier\n"); - +#endif return 0; } +early_initcall(event_trace_memsetup); +core_initcall(event_trace_enable); fs_initcall(event_trace_init); #ifdef CONFIG_FTRACE_STARTUP_TEST @@ -1249,33 +2539,54 @@ static __init void event_test_stuff(void) */ static __init void event_trace_self_tests(void) { + struct ftrace_subsystem_dir *dir; + struct ftrace_event_file *file; struct ftrace_event_call *call; struct event_subsystem *system; + struct trace_array *tr; int ret; + tr = top_trace_array(); + if (!tr) + return; + pr_info("Running tests on trace events:\n"); - list_for_each_entry(call, &ftrace_events, list) { + list_for_each_entry(file, &tr->events, list) { - /* Only test those that have a regfunc */ - if (!call->regfunc) + call = file->event_call; + + /* Only test those that have a probe */ + if (!call->class || !call->class->probe) continue; - pr_info("Testing event %s: ", call->name); +/* + * Testing syscall events here is pretty useless, but + * we still do it if configured. But this is time consuming. + * What we really need is a user thread to perform the + * syscalls as we test. + */ +#ifndef CONFIG_EVENT_TRACE_TEST_SYSCALLS + if (call->class->system && + strcmp(call->class->system, "syscalls") == 0) + continue; +#endif + + pr_info("Testing event %s: ", ftrace_event_name(call)); /* * If an event is already enabled, someone is using * it and the self test should not be on. */ - if (call->enabled) { + if (file->flags & FTRACE_EVENT_FL_ENABLED) { pr_warning("Enabled event during self test!\n"); WARN_ON_ONCE(1); continue; } - ftrace_event_enable_disable(call, 1); + ftrace_event_enable_disable(file, 1); event_test_stuff(); - ftrace_event_enable_disable(call, 0); + ftrace_event_enable_disable(file, 0); pr_cont("OK\n"); } @@ -1284,7 +2595,9 @@ static __init void event_trace_self_tests(void) pr_info("Running tests on trace event systems:\n"); - list_for_each_entry(system, &event_subsystems, list) { + list_for_each_entry(dir, &tr->systems, list) { + + system = dir->subsystem; /* the ftrace system is special, skip it */ if (strcmp(system->name, "ftrace") == 0) @@ -1292,7 +2605,7 @@ static __init void event_trace_self_tests(void) pr_info("Testing event system %s: ", system->name); - ret = __ftrace_set_clr_event(NULL, system->name, NULL, 1); + ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 1); if (WARN_ON_ONCE(ret)) { pr_warning("error enabling system %s\n", system->name); @@ -1301,10 +2614,12 @@ static __init void event_trace_self_tests(void) event_test_stuff(); - ret = __ftrace_set_clr_event(NULL, system->name, NULL, 0); - if (WARN_ON_ONCE(ret)) + ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 0); + if (WARN_ON_ONCE(ret)) { pr_warning("error disabling system %s\n", system->name); + continue; + } pr_cont("OK\n"); } @@ -1314,7 +2629,7 @@ static __init void event_trace_self_tests(void) pr_info("Running tests on all trace events:\n"); pr_info("Testing all events: "); - ret = __ftrace_set_clr_event(NULL, NULL, NULL, 1); + ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 1); if (WARN_ON_ONCE(ret)) { pr_warning("error enabling all events\n"); return; @@ -1323,7 +2638,7 @@ static __init void event_trace_self_tests(void) event_test_stuff(); /* reset sysname */ - ret = __ftrace_set_clr_event(NULL, NULL, NULL, 0); + ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 0); if (WARN_ON_ONCE(ret)) { pr_warning("error disabling all events\n"); return; @@ -1334,30 +2649,32 @@ static __init void event_trace_self_tests(void) #ifdef CONFIG_FUNCTION_TRACER -static DEFINE_PER_CPU(atomic_t, test_event_disable); +static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable); static void -function_test_events_call(unsigned long ip, unsigned long parent_ip) +function_test_events_call(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct pt_regs *pt_regs) { struct ring_buffer_event *event; + struct ring_buffer *buffer; struct ftrace_entry *entry; unsigned long flags; long disabled; - int resched; int cpu; int pc; pc = preempt_count(); - resched = ftrace_preempt_disable(); + preempt_disable_notrace(); cpu = raw_smp_processor_id(); - disabled = atomic_inc_return(&per_cpu(test_event_disable, cpu)); + disabled = atomic_inc_return(&per_cpu(ftrace_test_event_disable, cpu)); if (disabled != 1) goto out; local_save_flags(flags); - event = trace_current_buffer_lock_reserve(TRACE_FN, sizeof(*entry), + event = trace_current_buffer_lock_reserve(&buffer, + TRACE_FN, sizeof(*entry), flags, pc); if (!event) goto out; @@ -1365,21 +2682,27 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip) entry->ip = ip; entry->parent_ip = parent_ip; - trace_nowake_buffer_unlock_commit(event, flags, pc); + trace_buffer_unlock_commit(buffer, event, flags, pc); out: - atomic_dec(&per_cpu(test_event_disable, cpu)); - ftrace_preempt_enable(resched); + atomic_dec(&per_cpu(ftrace_test_event_disable, cpu)); + preempt_enable_notrace(); } static struct ftrace_ops trace_ops __initdata = { .func = function_test_events_call, + .flags = FTRACE_OPS_FL_RECURSION_SAFE, }; static __init void event_trace_self_test_with_function(void) { - register_ftrace_function(&trace_ops); + int ret; + ret = register_ftrace_function(&trace_ops); + if (WARN_ON(ret < 0)) { + pr_info("Failed to enable function tracer for event tests\n"); + return; + } pr_info("Running tests again, along with the function tracer\n"); event_trace_self_tests(); unregister_ftrace_function(&trace_ops); @@ -1392,10 +2715,10 @@ static __init void event_trace_self_test_with_function(void) static __init int event_trace_self_tests_init(void) { - - event_trace_self_tests(); - - event_trace_self_test_with_function(); + if (!tracing_selftest_disabled) { + event_trace_self_tests(); + event_trace_self_test_with_function(); + } return 0; } diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 936c621bbf4..8a8631926a0 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -18,25 +18,33 @@ * Copyright (C) 2009 Tom Zanussi <tzanussi@gmail.com> */ -#include <linux/debugfs.h> -#include <linux/uaccess.h> #include <linux/module.h> #include <linux/ctype.h> #include <linux/mutex.h> +#include <linux/perf_event.h> +#include <linux/slab.h> #include "trace.h" #include "trace_output.h" +#define DEFAULT_SYS_FILTER_MESSAGE \ + "### global filter ###\n" \ + "# Use this to set filters for multiple events.\n" \ + "# Only events with the given fields will be affected.\n" \ + "# If no events are modified, an error message will be displayed here" + enum filter_op_ids { OP_OR, OP_AND, + OP_GLOB, OP_NE, OP_EQ, OP_LT, OP_LE, OP_GT, OP_GE, + OP_BAND, OP_NONE, OP_OPEN_PAREN, }; @@ -47,17 +55,20 @@ struct filter_op { int precedence; }; +/* Order must be the same as enum filter_op_ids above */ static struct filter_op filter_ops[] = { - { OP_OR, "||", 1 }, - { OP_AND, "&&", 2 }, - { OP_NE, "!=", 4 }, - { OP_EQ, "==", 4 }, - { OP_LT, "<", 5 }, - { OP_LE, "<=", 5 }, - { OP_GT, ">", 5 }, - { OP_GE, ">=", 5 }, - { OP_NONE, "OP_NONE", 0 }, - { OP_OPEN_PAREN, "(", 0 }, + { OP_OR, "||", 1 }, + { OP_AND, "&&", 2 }, + { OP_GLOB, "~", 4 }, + { OP_NE, "!=", 4 }, + { OP_EQ, "==", 4 }, + { OP_LT, "<", 5 }, + { OP_LE, "<=", 5 }, + { OP_GT, ">", 5 }, + { OP_GE, ">=", 5 }, + { OP_BAND, "&", 6 }, + { OP_NONE, "OP_NONE", 0 }, + { OP_OPEN_PAREN, "(", 0 }, }; enum { @@ -73,6 +84,7 @@ enum { FILT_ERR_TOO_MANY_PREDS, FILT_ERR_MISSING_FIELD, FILT_ERR_INVALID_FILTER, + FILT_ERR_IP_FIELD_ONLY, }; static char *err_text[] = { @@ -88,6 +100,7 @@ static char *err_text[] = { "Too many terms in predicate expression", "Missing field name and/or value", "Meaningless filter expression", + "Only 'ip' field is supported for function trace", }; struct opstack_op { @@ -121,6 +134,53 @@ struct filter_parse_state { } operand; }; +struct pred_stack { + struct filter_pred **preds; + int index; +}; + +#define DEFINE_COMPARISON_PRED(type) \ +static int filter_pred_##type(struct filter_pred *pred, void *event) \ +{ \ + type *addr = (type *)(event + pred->offset); \ + type val = (type)pred->val; \ + int match = 0; \ + \ + switch (pred->op) { \ + case OP_LT: \ + match = (*addr < val); \ + break; \ + case OP_LE: \ + match = (*addr <= val); \ + break; \ + case OP_GT: \ + match = (*addr > val); \ + break; \ + case OP_GE: \ + match = (*addr >= val); \ + break; \ + case OP_BAND: \ + match = (*addr & val); \ + break; \ + default: \ + break; \ + } \ + \ + return match; \ +} + +#define DEFINE_EQUALITY_PRED(size) \ +static int filter_pred_##size(struct filter_pred *pred, void *event) \ +{ \ + u##size *addr = (u##size *)(event + pred->offset); \ + u##size val = (u##size)pred->val; \ + int match; \ + \ + match = (val == *addr) ^ pred->not; \ + \ + return match; \ +} + DEFINE_COMPARISON_PRED(s64); DEFINE_COMPARISON_PRED(u64); DEFINE_COMPARISON_PRED(s32); @@ -135,30 +195,29 @@ DEFINE_EQUALITY_PRED(32); DEFINE_EQUALITY_PRED(16); DEFINE_EQUALITY_PRED(8); -static int filter_pred_and(struct filter_pred *pred __attribute((unused)), - void *event __attribute((unused)), - int val1, int val2) +/* Filter predicate for fixed sized arrays of characters */ +static int filter_pred_string(struct filter_pred *pred, void *event) { - return val1 && val2; -} + char *addr = (char *)(event + pred->offset); + int cmp, match; -static int filter_pred_or(struct filter_pred *pred __attribute((unused)), - void *event __attribute((unused)), - int val1, int val2) -{ - return val1 || val2; + cmp = pred->regex.match(addr, &pred->regex, pred->regex.field_len); + + match = cmp ^ pred->not; + + return match; } -/* Filter predicate for fixed sized arrays of characters */ -static int filter_pred_string(struct filter_pred *pred, void *event, - int val1, int val2) +/* Filter predicate for char * pointers */ +static int filter_pred_pchar(struct filter_pred *pred, void *event) { - char *addr = (char *)(event + pred->offset); + char **addr = (char **)(event + pred->offset); int cmp, match; + int len = strlen(*addr) + 1; /* including tailing '\0' */ - cmp = strncmp(addr, pred->str_val, pred->str_len); + cmp = pred->regex.match(*addr, &pred->regex, len); - match = (!cmp) ^ pred->not; + match = cmp ^ pred->not; return match; } @@ -173,53 +232,340 @@ static int filter_pred_string(struct filter_pred *pred, void *event, * and add it to the address of the entry, and at last we have * the address of the string. */ -static int filter_pred_strloc(struct filter_pred *pred, void *event, - int val1, int val2) +static int filter_pred_strloc(struct filter_pred *pred, void *event) { - unsigned short str_loc = *(unsigned short *)(event + pred->offset); + u32 str_item = *(u32 *)(event + pred->offset); + int str_loc = str_item & 0xffff; + int str_len = str_item >> 16; char *addr = (char *)(event + str_loc); int cmp, match; - cmp = strncmp(addr, pred->str_val, pred->str_len); + cmp = pred->regex.match(addr, &pred->regex, str_len); - match = (!cmp) ^ pred->not; + match = cmp ^ pred->not; return match; } -static int filter_pred_none(struct filter_pred *pred, void *event, - int val1, int val2) +static int filter_pred_none(struct filter_pred *pred, void *event) { return 0; } -/* return 1 if event matches, 0 otherwise (discard) */ -int filter_match_preds(struct ftrace_event_call *call, void *rec) +/* + * regex_match_foo - Basic regex callbacks + * + * @str: the string to be searched + * @r: the regex structure containing the pattern string + * @len: the length of the string to be searched (including '\0') + * + * Note: + * - @str might not be NULL-terminated if it's of type DYN_STRING + * or STATIC_STRING + */ + +static int regex_match_full(char *str, struct regex *r, int len) { - struct event_filter *filter = call->filter; - int match, top = 0, val1 = 0, val2 = 0; - int stack[MAX_FILTER_PRED]; - struct filter_pred *pred; + if (strncmp(str, r->pattern, len) == 0) + return 1; + return 0; +} + +static int regex_match_front(char *str, struct regex *r, int len) +{ + if (strncmp(str, r->pattern, r->len) == 0) + return 1; + return 0; +} + +static int regex_match_middle(char *str, struct regex *r, int len) +{ + if (strnstr(str, r->pattern, len)) + return 1; + return 0; +} + +static int regex_match_end(char *str, struct regex *r, int len) +{ + int strlen = len - 1; + + if (strlen >= r->len && + memcmp(str + strlen - r->len, r->pattern, r->len) == 0) + return 1; + return 0; +} + +/** + * filter_parse_regex - parse a basic regex + * @buff: the raw regex + * @len: length of the regex + * @search: will point to the beginning of the string to compare + * @not: tell whether the match will have to be inverted + * + * This passes in a buffer containing a regex and this function will + * set search to point to the search part of the buffer and + * return the type of search it is (see enum above). + * This does modify buff. + * + * Returns enum type. + * search returns the pointer to use for comparison. + * not returns 1 if buff started with a '!' + * 0 otherwise. + */ +enum regex_type filter_parse_regex(char *buff, int len, char **search, int *not) +{ + int type = MATCH_FULL; int i; - for (i = 0; i < filter->n_preds; i++) { - pred = filter->preds[i]; - if (!pred->pop_n) { - match = pred->fn(pred, rec, val1, val2); - stack[top++] = match; + if (buff[0] == '!') { + *not = 1; + buff++; + len--; + } else + *not = 0; + + *search = buff; + + for (i = 0; i < len; i++) { + if (buff[i] == '*') { + if (!i) { + *search = buff + 1; + type = MATCH_END_ONLY; + } else { + if (type == MATCH_END_ONLY) + type = MATCH_MIDDLE_ONLY; + else + type = MATCH_FRONT_ONLY; + buff[i] = 0; + break; + } + } + } + + return type; +} + +static void filter_build_regex(struct filter_pred *pred) +{ + struct regex *r = &pred->regex; + char *search; + enum regex_type type = MATCH_FULL; + int not = 0; + + if (pred->op == OP_GLOB) { + type = filter_parse_regex(r->pattern, r->len, &search, ¬); + r->len = strlen(search); + memmove(r->pattern, search, r->len+1); + } + + switch (type) { + case MATCH_FULL: + r->match = regex_match_full; + break; + case MATCH_FRONT_ONLY: + r->match = regex_match_front; + break; + case MATCH_MIDDLE_ONLY: + r->match = regex_match_middle; + break; + case MATCH_END_ONLY: + r->match = regex_match_end; + break; + } + + pred->not ^= not; +} + +enum move_type { + MOVE_DOWN, + MOVE_UP_FROM_LEFT, + MOVE_UP_FROM_RIGHT +}; + +static struct filter_pred * +get_pred_parent(struct filter_pred *pred, struct filter_pred *preds, + int index, enum move_type *move) +{ + if (pred->parent & FILTER_PRED_IS_RIGHT) + *move = MOVE_UP_FROM_RIGHT; + else + *move = MOVE_UP_FROM_LEFT; + pred = &preds[pred->parent & ~FILTER_PRED_IS_RIGHT]; + + return pred; +} + +enum walk_return { + WALK_PRED_ABORT, + WALK_PRED_PARENT, + WALK_PRED_DEFAULT, +}; + +typedef int (*filter_pred_walkcb_t) (enum move_type move, + struct filter_pred *pred, + int *err, void *data); + +static int walk_pred_tree(struct filter_pred *preds, + struct filter_pred *root, + filter_pred_walkcb_t cb, void *data) +{ + struct filter_pred *pred = root; + enum move_type move = MOVE_DOWN; + int done = 0; + + if (!preds) + return -EINVAL; + + do { + int err = 0, ret; + + ret = cb(move, pred, &err, data); + if (ret == WALK_PRED_ABORT) + return err; + if (ret == WALK_PRED_PARENT) + goto get_parent; + + switch (move) { + case MOVE_DOWN: + if (pred->left != FILTER_PRED_INVALID) { + pred = &preds[pred->left]; + continue; + } + goto get_parent; + case MOVE_UP_FROM_LEFT: + pred = &preds[pred->right]; + move = MOVE_DOWN; + continue; + case MOVE_UP_FROM_RIGHT: + get_parent: + if (pred == root) + break; + pred = get_pred_parent(pred, preds, + pred->parent, + &move); continue; } - if (pred->pop_n > top) { - WARN_ON_ONCE(1); - return 0; + done = 1; + } while (!done); + + /* We are fine. */ + return 0; +} + +/* + * A series of AND or ORs where found together. Instead of + * climbing up and down the tree branches, an array of the + * ops were made in order of checks. We can just move across + * the array and short circuit if needed. + */ +static int process_ops(struct filter_pred *preds, + struct filter_pred *op, void *rec) +{ + struct filter_pred *pred; + int match = 0; + int type; + int i; + + /* + * Micro-optimization: We set type to true if op + * is an OR and false otherwise (AND). Then we + * just need to test if the match is equal to + * the type, and if it is, we can short circuit the + * rest of the checks: + * + * if ((match && op->op == OP_OR) || + * (!match && op->op == OP_AND)) + * return match; + */ + type = op->op == OP_OR; + + for (i = 0; i < op->val; i++) { + pred = &preds[op->ops[i]]; + if (!WARN_ON_ONCE(!pred->fn)) + match = pred->fn(pred, rec); + if (!!match == type) + return match; + } + return match; +} + +struct filter_match_preds_data { + struct filter_pred *preds; + int match; + void *rec; +}; + +static int filter_match_preds_cb(enum move_type move, struct filter_pred *pred, + int *err, void *data) +{ + struct filter_match_preds_data *d = data; + + *err = 0; + switch (move) { + case MOVE_DOWN: + /* only AND and OR have children */ + if (pred->left != FILTER_PRED_INVALID) { + /* If ops is set, then it was folded. */ + if (!pred->ops) + return WALK_PRED_DEFAULT; + /* We can treat folded ops as a leaf node */ + d->match = process_ops(d->preds, pred, d->rec); + } else { + if (!WARN_ON_ONCE(!pred->fn)) + d->match = pred->fn(pred, d->rec); } - val1 = stack[--top]; - val2 = stack[--top]; - match = pred->fn(pred, rec, val1, val2); - stack[top++] = match; + + return WALK_PRED_PARENT; + case MOVE_UP_FROM_LEFT: + /* + * Check for short circuits. + * + * Optimization: !!match == (pred->op == OP_OR) + * is the same as: + * if ((match && pred->op == OP_OR) || + * (!match && pred->op == OP_AND)) + */ + if (!!d->match == (pred->op == OP_OR)) + return WALK_PRED_PARENT; + break; + case MOVE_UP_FROM_RIGHT: + break; } - return stack[--top]; + return WALK_PRED_DEFAULT; +} + +/* return 1 if event matches, 0 otherwise (discard) */ +int filter_match_preds(struct event_filter *filter, void *rec) +{ + struct filter_pred *preds; + struct filter_pred *root; + struct filter_match_preds_data data = { + /* match is currently meaningless */ + .match = -1, + .rec = rec, + }; + int n_preds, ret; + + /* no filter is considered a match */ + if (!filter) + return 1; + + n_preds = filter->n_preds; + if (!n_preds) + return 1; + + /* + * n_preds, root and filter->preds are protect with preemption disabled. + */ + root = rcu_dereference_sched(filter->root); + if (!root) + return 1; + + data.preds = preds = rcu_dereference_sched(filter->preds); + ret = walk_pred_tree(preds, root, filter_match_preds_cb, &data); + WARN_ON(ret); + return data.match; } EXPORT_SYMBOL_GPL(filter_match_preds); @@ -231,6 +577,9 @@ static void parse_error(struct filter_parse_state *ps, int err, int pos) static void remove_filter_string(struct event_filter *filter) { + if (!filter) + return; + kfree(filter->filter_string); filter->filter_string = NULL; } @@ -288,192 +637,306 @@ static void append_filter_err(struct filter_parse_state *ps, free_page((unsigned long) buf); } -void print_event_filter(struct ftrace_event_call *call, struct trace_seq *s) +static inline struct event_filter *event_filter(struct ftrace_event_file *file) { - struct event_filter *filter = call->filter; + if (file->event_call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + return file->event_call->filter; + else + return file->filter; +} - mutex_lock(&event_mutex); - if (filter->filter_string) +/* caller must hold event_mutex */ +void print_event_filter(struct ftrace_event_file *file, struct trace_seq *s) +{ + struct event_filter *filter = event_filter(file); + + if (filter && filter->filter_string) trace_seq_printf(s, "%s\n", filter->filter_string); else - trace_seq_printf(s, "none\n"); - mutex_unlock(&event_mutex); + trace_seq_puts(s, "none\n"); } void print_subsystem_event_filter(struct event_subsystem *system, struct trace_seq *s) { - struct event_filter *filter = system->filter; + struct event_filter *filter; mutex_lock(&event_mutex); - if (filter->filter_string) + filter = system->filter; + if (filter && filter->filter_string) trace_seq_printf(s, "%s\n", filter->filter_string); else - trace_seq_printf(s, "none\n"); + trace_seq_puts(s, DEFAULT_SYS_FILTER_MESSAGE "\n"); mutex_unlock(&event_mutex); } -static struct ftrace_event_field * -find_event_field(struct ftrace_event_call *call, char *name) +static int __alloc_pred_stack(struct pred_stack *stack, int n_preds) { - struct ftrace_event_field *field; - - list_for_each_entry(field, &call->fields, link) { - if (!strcmp(field->name, name)) - return field; - } + stack->preds = kcalloc(n_preds + 1, sizeof(*stack->preds), GFP_KERNEL); + if (!stack->preds) + return -ENOMEM; + stack->index = n_preds; + return 0; +} - return NULL; +static void __free_pred_stack(struct pred_stack *stack) +{ + kfree(stack->preds); + stack->index = 0; } -static void filter_free_pred(struct filter_pred *pred) +static int __push_pred_stack(struct pred_stack *stack, + struct filter_pred *pred) { - if (!pred) - return; + int index = stack->index; + + if (WARN_ON(index == 0)) + return -ENOSPC; - kfree(pred->field_name); - kfree(pred); + stack->preds[--index] = pred; + stack->index = index; + return 0; } -static void filter_clear_pred(struct filter_pred *pred) +static struct filter_pred * +__pop_pred_stack(struct pred_stack *stack) { - kfree(pred->field_name); - pred->field_name = NULL; - pred->str_len = 0; + struct filter_pred *pred; + int index = stack->index; + + pred = stack->preds[index++]; + if (!pred) + return NULL; + + stack->index = index; + return pred; } -static int filter_set_pred(struct filter_pred *dest, - struct filter_pred *src, - filter_pred_fn_t fn) +static int filter_set_pred(struct event_filter *filter, + int idx, + struct pred_stack *stack, + struct filter_pred *src) { + struct filter_pred *dest = &filter->preds[idx]; + struct filter_pred *left; + struct filter_pred *right; + *dest = *src; - if (src->field_name) { - dest->field_name = kstrdup(src->field_name, GFP_KERNEL); - if (!dest->field_name) - return -ENOMEM; + dest->index = idx; + + if (dest->op == OP_OR || dest->op == OP_AND) { + right = __pop_pred_stack(stack); + left = __pop_pred_stack(stack); + if (!left || !right) + return -EINVAL; + /* + * If both children can be folded + * and they are the same op as this op or a leaf, + * then this op can be folded. + */ + if (left->index & FILTER_PRED_FOLD && + (left->op == dest->op || + left->left == FILTER_PRED_INVALID) && + right->index & FILTER_PRED_FOLD && + (right->op == dest->op || + right->left == FILTER_PRED_INVALID)) + dest->index |= FILTER_PRED_FOLD; + + dest->left = left->index & ~FILTER_PRED_FOLD; + dest->right = right->index & ~FILTER_PRED_FOLD; + left->parent = dest->index & ~FILTER_PRED_FOLD; + right->parent = dest->index | FILTER_PRED_IS_RIGHT; + } else { + /* + * Make dest->left invalid to be used as a quick + * way to know this is a leaf node. + */ + dest->left = FILTER_PRED_INVALID; + + /* All leafs allow folding the parent ops. */ + dest->index |= FILTER_PRED_FOLD; } - dest->fn = fn; - return 0; + return __push_pred_stack(stack, dest); } -static void filter_disable_preds(struct ftrace_event_call *call) +static void __free_preds(struct event_filter *filter) { - struct event_filter *filter = call->filter; int i; - call->filter_active = 0; + if (filter->preds) { + for (i = 0; i < filter->n_preds; i++) + kfree(filter->preds[i].ops); + kfree(filter->preds); + filter->preds = NULL; + } + filter->a_preds = 0; filter->n_preds = 0; +} - for (i = 0; i < MAX_FILTER_PRED; i++) - filter->preds[i]->fn = filter_pred_none; +static void call_filter_disable(struct ftrace_event_call *call) +{ + call->flags &= ~TRACE_EVENT_FL_FILTERED; } -void destroy_preds(struct ftrace_event_call *call) +static void filter_disable(struct ftrace_event_file *file) { - struct event_filter *filter = call->filter; - int i; + struct ftrace_event_call *call = file->event_call; - for (i = 0; i < MAX_FILTER_PRED; i++) { - if (filter->preds[i]) - filter_free_pred(filter->preds[i]); - } - kfree(filter->preds); + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + call_filter_disable(call); + else + file->flags &= ~FTRACE_EVENT_FL_FILTERED; +} + +static void __free_filter(struct event_filter *filter) +{ + if (!filter) + return; + + __free_preds(filter); kfree(filter->filter_string); kfree(filter); +} + +void free_event_filter(struct event_filter *filter) +{ + __free_filter(filter); +} + +void destroy_call_preds(struct ftrace_event_call *call) +{ + __free_filter(call->filter); call->filter = NULL; } -int init_preds(struct ftrace_event_call *call) +static void destroy_file_preds(struct ftrace_event_file *file) +{ + __free_filter(file->filter); + file->filter = NULL; +} + +/* + * Called when destroying the ftrace_event_file. + * The file is being freed, so we do not need to worry about + * the file being currently used. This is for module code removing + * the tracepoints from within it. + */ +void destroy_preds(struct ftrace_event_file *file) +{ + if (file->event_call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + destroy_call_preds(file->event_call); + else + destroy_file_preds(file); +} + +static struct event_filter *__alloc_filter(void) { struct event_filter *filter; + + filter = kzalloc(sizeof(*filter), GFP_KERNEL); + return filter; +} + +static int __alloc_preds(struct event_filter *filter, int n_preds) +{ struct filter_pred *pred; int i; - filter = call->filter = kzalloc(sizeof(*filter), GFP_KERNEL); - if (!call->filter) - return -ENOMEM; + if (filter->preds) + __free_preds(filter); - call->filter_active = 0; - filter->n_preds = 0; + filter->preds = kcalloc(n_preds, sizeof(*filter->preds), GFP_KERNEL); - filter->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred), GFP_KERNEL); if (!filter->preds) - goto oom; + return -ENOMEM; - for (i = 0; i < MAX_FILTER_PRED; i++) { - pred = kzalloc(sizeof(*pred), GFP_KERNEL); - if (!pred) - goto oom; + filter->a_preds = n_preds; + filter->n_preds = 0; + + for (i = 0; i < n_preds; i++) { + pred = &filter->preds[i]; pred->fn = filter_pred_none; - filter->preds[i] = pred; } return 0; +} -oom: - destroy_preds(call); +static inline void __remove_filter(struct ftrace_event_file *file) +{ + struct ftrace_event_call *call = file->event_call; - return -ENOMEM; + filter_disable(file); + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + remove_filter_string(call->filter); + else + remove_filter_string(file->filter); } -EXPORT_SYMBOL_GPL(init_preds); -static void filter_free_subsystem_preds(struct event_subsystem *system) +static void filter_free_subsystem_preds(struct event_subsystem *system, + struct trace_array *tr) { - struct event_filter *filter = system->filter; + struct ftrace_event_file *file; struct ftrace_event_call *call; - int i; - if (filter->n_preds) { - for (i = 0; i < filter->n_preds; i++) - filter_free_pred(filter->preds[i]); - kfree(filter->preds); - filter->preds = NULL; - filter->n_preds = 0; + list_for_each_entry(file, &tr->events, list) { + call = file->event_call; + if (strcmp(call->class->system, system->name) != 0) + continue; + + __remove_filter(file); } +} - list_for_each_entry(call, &ftrace_events, list) { - if (!call->define_fields) - continue; +static inline void __free_subsystem_filter(struct ftrace_event_file *file) +{ + struct ftrace_event_call *call = file->event_call; - if (!strcmp(call->system, system->name)) { - filter_disable_preds(call); - remove_filter_string(call->filter); - } + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) { + __free_filter(call->filter); + call->filter = NULL; + } else { + __free_filter(file->filter); + file->filter = NULL; } } -static int filter_add_pred_fn(struct filter_parse_state *ps, - struct ftrace_event_call *call, - struct filter_pred *pred, - filter_pred_fn_t fn) +static void filter_free_subsystem_filters(struct event_subsystem *system, + struct trace_array *tr) { - struct event_filter *filter = call->filter; - int idx, err; + struct ftrace_event_file *file; + struct ftrace_event_call *call; + + list_for_each_entry(file, &tr->events, list) { + call = file->event_call; + if (strcmp(call->class->system, system->name) != 0) + continue; + __free_subsystem_filter(file); + } +} - if (filter->n_preds == MAX_FILTER_PRED) { +static int filter_add_pred(struct filter_parse_state *ps, + struct event_filter *filter, + struct filter_pred *pred, + struct pred_stack *stack) +{ + int err; + + if (WARN_ON(filter->n_preds == filter->a_preds)) { parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0); return -ENOSPC; } - idx = filter->n_preds; - filter_clear_pred(filter->preds[idx]); - err = filter_set_pred(filter->preds[idx], pred, fn); + err = filter_set_pred(filter, filter->n_preds, stack, pred); if (err) return err; filter->n_preds++; - call->filter_active = 1; return 0; } -enum { - FILTER_STATIC_STRING = 1, - FILTER_DYN_STRING -}; - -static int is_string_field(const char *type) +int filter_assign_type(const char *type) { if (strstr(type, "__data_loc") && strstr(type, "char")) return FILTER_DYN_STRING; @@ -481,12 +944,27 @@ static int is_string_field(const char *type) if (strchr(type, '[') && strstr(type, "char")) return FILTER_STATIC_STRING; - return 0; + return FILTER_OTHER; +} + +static bool is_function_field(struct ftrace_event_field *field) +{ + return field->filter_type == FILTER_TRACE_FN; +} + +static bool is_string_field(struct ftrace_event_field *field) +{ + return field->filter_type == FILTER_DYN_STRING || + field->filter_type == FILTER_STATIC_STRING || + field->filter_type == FILTER_PTR_STRING; } static int is_legal_op(struct ftrace_event_field *field, int op) { - if (is_string_field(field->type) && (op != OP_EQ && op != OP_NE)) + if (is_string_field(field) && + (op != OP_EQ && op != OP_NE && op != OP_GLOB)) + return 0; + if (!is_string_field(field) && op == OP_GLOB) return 0; return 1; @@ -535,32 +1013,15 @@ static filter_pred_fn_t select_comparison_fn(int op, int field_size, return fn; } -static int filter_add_pred(struct filter_parse_state *ps, - struct ftrace_event_call *call, - struct filter_pred *pred) +static int init_pred(struct filter_parse_state *ps, + struct ftrace_event_field *field, + struct filter_pred *pred) + { - struct ftrace_event_field *field; - filter_pred_fn_t fn; + filter_pred_fn_t fn = filter_pred_none; unsigned long long val; - int string_type; int ret; - pred->fn = filter_pred_none; - - if (pred->op == OP_AND) { - pred->pop_n = 2; - return filter_add_pred_fn(ps, call, pred, filter_pred_and); - } else if (pred->op == OP_OR) { - pred->pop_n = 2; - return filter_add_pred_fn(ps, call, pred, filter_pred_or); - } - - field = find_event_field(call, pred->field_name); - if (!field) { - parse_error(ps, FILT_ERR_FIELD_NOT_FOUND, 0); - return -EINVAL; - } - pred->offset = field->offset; if (!is_legal_op(field, pred->op)) { @@ -568,83 +1029,45 @@ static int filter_add_pred(struct filter_parse_state *ps, return -EINVAL; } - string_type = is_string_field(field->type); - if (string_type) { - if (string_type == FILTER_STATIC_STRING) + if (is_string_field(field)) { + filter_build_regex(pred); + + if (field->filter_type == FILTER_STATIC_STRING) { fn = filter_pred_string; - else + pred->regex.field_len = field->size; + } else if (field->filter_type == FILTER_DYN_STRING) fn = filter_pred_strloc; - pred->str_len = field->size; - if (pred->op == OP_NE) - pred->not = 1; - return filter_add_pred_fn(ps, call, pred, fn); + else + fn = filter_pred_pchar; + } else if (is_function_field(field)) { + if (strcmp(field->name, "ip")) { + parse_error(ps, FILT_ERR_IP_FIELD_ONLY, 0); + return -EINVAL; + } } else { if (field->is_signed) - ret = strict_strtoll(pred->str_val, 0, &val); + ret = kstrtoll(pred->regex.pattern, 0, &val); else - ret = strict_strtoull(pred->str_val, 0, &val); + ret = kstrtoull(pred->regex.pattern, 0, &val); if (ret) { parse_error(ps, FILT_ERR_ILLEGAL_INTVAL, 0); return -EINVAL; } pred->val = val; - } - fn = select_comparison_fn(pred->op, field->size, field->is_signed); - if (!fn) { - parse_error(ps, FILT_ERR_INVALID_OP, 0); - return -EINVAL; + fn = select_comparison_fn(pred->op, field->size, + field->is_signed); + if (!fn) { + parse_error(ps, FILT_ERR_INVALID_OP, 0); + return -EINVAL; + } } if (pred->op == OP_NE) pred->not = 1; - return filter_add_pred_fn(ps, call, pred, fn); -} - -static int filter_add_subsystem_pred(struct filter_parse_state *ps, - struct event_subsystem *system, - struct filter_pred *pred, - char *filter_string) -{ - struct event_filter *filter = system->filter; - struct ftrace_event_call *call; - int err = 0; - - if (!filter->preds) { - filter->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred), - GFP_KERNEL); - - if (!filter->preds) - return -ENOMEM; - } - - if (filter->n_preds == MAX_FILTER_PRED) { - parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0); - return -ENOSPC; - } - - filter->preds[filter->n_preds] = pred; - filter->n_preds++; - - list_for_each_entry(call, &ftrace_events, list) { - - if (!call->define_fields) - continue; - - if (strcmp(call->system, system->name)) - continue; - - err = filter_add_pred(ps, call, pred); - if (err) { - filter_free_subsystem_preds(system); - parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0); - goto out; - } - replace_filter_string(call->filter, filter_string); - } -out: - return err; + pred->fn = fn; + return 0; } static void parse_init(struct filter_parse_state *ps, @@ -844,8 +1267,9 @@ static void postfix_clear(struct filter_parse_state *ps) while (!list_empty(&ps->postfix)) { elt = list_first_entry(&ps->postfix, struct postfix_elt, list); - kfree(elt->operand); list_del(&elt->list); + kfree(elt->operand); + kfree(elt); } } @@ -941,39 +1365,34 @@ parse_operand: return 0; } -static struct filter_pred *create_pred(int op, char *operand1, char *operand2) +static struct filter_pred *create_pred(struct filter_parse_state *ps, + struct ftrace_event_call *call, + int op, char *operand1, char *operand2) { - struct filter_pred *pred; + struct ftrace_event_field *field; + static struct filter_pred pred; - pred = kzalloc(sizeof(*pred), GFP_KERNEL); - if (!pred) - return NULL; + memset(&pred, 0, sizeof(pred)); + pred.op = op; - pred->field_name = kstrdup(operand1, GFP_KERNEL); - if (!pred->field_name) { - kfree(pred); + if (op == OP_AND || op == OP_OR) + return &pred; + + if (!operand1 || !operand2) { + parse_error(ps, FILT_ERR_MISSING_FIELD, 0); return NULL; } - strcpy(pred->str_val, operand2); - pred->str_len = strlen(operand2); - - pred->op = op; - - return pred; -} - -static struct filter_pred *create_logical_pred(int op) -{ - struct filter_pred *pred; - - pred = kzalloc(sizeof(*pred), GFP_KERNEL); - if (!pred) + field = trace_find_event_field(call, operand1); + if (!field) { + parse_error(ps, FILT_ERR_FIELD_NOT_FOUND, 0); return NULL; + } - pred->op = op; - - return pred; + strcpy(pred.regex.pattern, operand2); + pred.regex.len = strlen(pred.regex.pattern); + pred.field = field; + return init_pred(ps, field, &pred) ? NULL : &pred; } static int check_preds(struct filter_parse_state *ps) @@ -1000,20 +1419,200 @@ static int check_preds(struct filter_parse_state *ps) return 0; } -static int replace_preds(struct event_subsystem *system, - struct ftrace_event_call *call, +static int count_preds(struct filter_parse_state *ps) +{ + struct postfix_elt *elt; + int n_preds = 0; + + list_for_each_entry(elt, &ps->postfix, list) { + if (elt->op == OP_NONE) + continue; + n_preds++; + } + + return n_preds; +} + +struct check_pred_data { + int count; + int max; +}; + +static int check_pred_tree_cb(enum move_type move, struct filter_pred *pred, + int *err, void *data) +{ + struct check_pred_data *d = data; + + if (WARN_ON(d->count++ > d->max)) { + *err = -EINVAL; + return WALK_PRED_ABORT; + } + return WALK_PRED_DEFAULT; +} + +/* + * The tree is walked at filtering of an event. If the tree is not correctly + * built, it may cause an infinite loop. Check here that the tree does + * indeed terminate. + */ +static int check_pred_tree(struct event_filter *filter, + struct filter_pred *root) +{ + struct check_pred_data data = { + /* + * The max that we can hit a node is three times. + * Once going down, once coming up from left, and + * once coming up from right. This is more than enough + * since leafs are only hit a single time. + */ + .max = 3 * filter->n_preds, + .count = 0, + }; + + return walk_pred_tree(filter->preds, root, + check_pred_tree_cb, &data); +} + +static int count_leafs_cb(enum move_type move, struct filter_pred *pred, + int *err, void *data) +{ + int *count = data; + + if ((move == MOVE_DOWN) && + (pred->left == FILTER_PRED_INVALID)) + (*count)++; + + return WALK_PRED_DEFAULT; +} + +static int count_leafs(struct filter_pred *preds, struct filter_pred *root) +{ + int count = 0, ret; + + ret = walk_pred_tree(preds, root, count_leafs_cb, &count); + WARN_ON(ret); + return count; +} + +struct fold_pred_data { + struct filter_pred *root; + int count; + int children; +}; + +static int fold_pred_cb(enum move_type move, struct filter_pred *pred, + int *err, void *data) +{ + struct fold_pred_data *d = data; + struct filter_pred *root = d->root; + + if (move != MOVE_DOWN) + return WALK_PRED_DEFAULT; + if (pred->left != FILTER_PRED_INVALID) + return WALK_PRED_DEFAULT; + + if (WARN_ON(d->count == d->children)) { + *err = -EINVAL; + return WALK_PRED_ABORT; + } + + pred->index &= ~FILTER_PRED_FOLD; + root->ops[d->count++] = pred->index; + return WALK_PRED_DEFAULT; +} + +static int fold_pred(struct filter_pred *preds, struct filter_pred *root) +{ + struct fold_pred_data data = { + .root = root, + .count = 0, + }; + int children; + + /* No need to keep the fold flag */ + root->index &= ~FILTER_PRED_FOLD; + + /* If the root is a leaf then do nothing */ + if (root->left == FILTER_PRED_INVALID) + return 0; + + /* count the children */ + children = count_leafs(preds, &preds[root->left]); + children += count_leafs(preds, &preds[root->right]); + + root->ops = kcalloc(children, sizeof(*root->ops), GFP_KERNEL); + if (!root->ops) + return -ENOMEM; + + root->val = children; + data.children = children; + return walk_pred_tree(preds, root, fold_pred_cb, &data); +} + +static int fold_pred_tree_cb(enum move_type move, struct filter_pred *pred, + int *err, void *data) +{ + struct filter_pred *preds = data; + + if (move != MOVE_DOWN) + return WALK_PRED_DEFAULT; + if (!(pred->index & FILTER_PRED_FOLD)) + return WALK_PRED_DEFAULT; + + *err = fold_pred(preds, pred); + if (*err) + return WALK_PRED_ABORT; + + /* eveyrhing below is folded, continue with parent */ + return WALK_PRED_PARENT; +} + +/* + * To optimize the processing of the ops, if we have several "ors" or + * "ands" together, we can put them in an array and process them all + * together speeding up the filter logic. + */ +static int fold_pred_tree(struct event_filter *filter, + struct filter_pred *root) +{ + return walk_pred_tree(filter->preds, root, fold_pred_tree_cb, + filter->preds); +} + +static int replace_preds(struct ftrace_event_call *call, + struct event_filter *filter, struct filter_parse_state *ps, - char *filter_string) + char *filter_string, + bool dry_run) { char *operand1 = NULL, *operand2 = NULL; struct filter_pred *pred; + struct filter_pred *root; struct postfix_elt *elt; + struct pred_stack stack = { }; /* init to NULL */ int err; + int n_preds = 0; + + n_preds = count_preds(ps); + if (n_preds >= MAX_FILTER_PRED) { + parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0); + return -ENOSPC; + } err = check_preds(ps); if (err) return err; + if (!dry_run) { + err = __alloc_pred_stack(&stack, n_preds); + if (err) + return err; + err = __alloc_preds(filter, n_preds); + if (err) + goto fail; + } + + n_preds = 0; list_for_each_entry(elt, &ps->postfix, list) { if (elt->op == OP_NONE) { if (!operand1) @@ -1022,133 +1621,829 @@ static int replace_preds(struct event_subsystem *system, operand2 = elt->operand; else { parse_error(ps, FILT_ERR_TOO_MANY_OPERANDS, 0); - return -EINVAL; + err = -EINVAL; + goto fail; } continue; } - if (elt->op == OP_AND || elt->op == OP_OR) { - pred = create_logical_pred(elt->op); - if (call) { - err = filter_add_pred(ps, call, pred); - filter_free_pred(pred); - } else - err = filter_add_subsystem_pred(ps, system, - pred, filter_string); - if (err) - return err; + if (WARN_ON(n_preds++ == MAX_FILTER_PRED)) { + parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0); + err = -ENOSPC; + goto fail; + } - operand1 = operand2 = NULL; - continue; + pred = create_pred(ps, call, elt->op, operand1, operand2); + if (!pred) { + err = -EINVAL; + goto fail; + } + + if (!dry_run) { + err = filter_add_pred(ps, filter, pred, &stack); + if (err) + goto fail; } - if (!operand1 || !operand2) { - parse_error(ps, FILT_ERR_MISSING_FIELD, 0); + operand1 = operand2 = NULL; + } + + if (!dry_run) { + /* We should have one item left on the stack */ + pred = __pop_pred_stack(&stack); + if (!pred) return -EINVAL; + /* This item is where we start from in matching */ + root = pred; + /* Make sure the stack is empty */ + pred = __pop_pred_stack(&stack); + if (WARN_ON(pred)) { + err = -EINVAL; + filter->root = NULL; + goto fail; } + err = check_pred_tree(filter, root); + if (err) + goto fail; - pred = create_pred(elt->op, operand1, operand2); - if (call) { - err = filter_add_pred(ps, call, pred); - filter_free_pred(pred); - } else - err = filter_add_subsystem_pred(ps, system, pred, - filter_string); + /* Optimize the tree */ + err = fold_pred_tree(filter, root); if (err) - return err; + goto fail; - operand1 = operand2 = NULL; + /* We don't set root until we know it works */ + barrier(); + filter->root = root; } - return 0; + err = 0; +fail: + __free_pred_stack(&stack); + return err; +} + +static inline void event_set_filtered_flag(struct ftrace_event_file *file) +{ + struct ftrace_event_call *call = file->event_call; + + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + call->flags |= TRACE_EVENT_FL_FILTERED; + else + file->flags |= FTRACE_EVENT_FL_FILTERED; } -int apply_event_filter(struct ftrace_event_call *call, char *filter_string) +static inline void event_set_filter(struct ftrace_event_file *file, + struct event_filter *filter) { + struct ftrace_event_call *call = file->event_call; + + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + rcu_assign_pointer(call->filter, filter); + else + rcu_assign_pointer(file->filter, filter); +} + +static inline void event_clear_filter(struct ftrace_event_file *file) +{ + struct ftrace_event_call *call = file->event_call; + + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + RCU_INIT_POINTER(call->filter, NULL); + else + RCU_INIT_POINTER(file->filter, NULL); +} + +static inline void +event_set_no_set_filter_flag(struct ftrace_event_file *file) +{ + struct ftrace_event_call *call = file->event_call; + + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + call->flags |= TRACE_EVENT_FL_NO_SET_FILTER; + else + file->flags |= FTRACE_EVENT_FL_NO_SET_FILTER; +} + +static inline void +event_clear_no_set_filter_flag(struct ftrace_event_file *file) +{ + struct ftrace_event_call *call = file->event_call; + + if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) + call->flags &= ~TRACE_EVENT_FL_NO_SET_FILTER; + else + file->flags &= ~FTRACE_EVENT_FL_NO_SET_FILTER; +} + +static inline bool +event_no_set_filter_flag(struct ftrace_event_file *file) +{ + struct ftrace_event_call *call = file->event_call; + + if (file->flags & FTRACE_EVENT_FL_NO_SET_FILTER) + return true; + + if ((call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) && + (call->flags & TRACE_EVENT_FL_NO_SET_FILTER)) + return true; + + return false; +} + +struct filter_list { + struct list_head list; + struct event_filter *filter; +}; + +static int replace_system_preds(struct event_subsystem *system, + struct trace_array *tr, + struct filter_parse_state *ps, + char *filter_string) +{ + struct ftrace_event_file *file; + struct ftrace_event_call *call; + struct filter_list *filter_item; + struct filter_list *tmp; + LIST_HEAD(filter_list); + bool fail = true; int err; - struct filter_parse_state *ps; + list_for_each_entry(file, &tr->events, list) { + call = file->event_call; + if (strcmp(call->class->system, system->name) != 0) + continue; - mutex_lock(&event_mutex); + /* + * Try to see if the filter can be applied + * (filter arg is ignored on dry_run) + */ + err = replace_preds(call, NULL, ps, filter_string, true); + if (err) + event_set_no_set_filter_flag(file); + else + event_clear_no_set_filter_flag(file); + } - if (!strcmp(strstrip(filter_string), "0")) { - filter_disable_preds(call); - remove_filter_string(call->filter); - mutex_unlock(&event_mutex); - return 0; + list_for_each_entry(file, &tr->events, list) { + struct event_filter *filter; + + call = file->event_call; + + if (strcmp(call->class->system, system->name) != 0) + continue; + + if (event_no_set_filter_flag(file)) + continue; + + filter_item = kzalloc(sizeof(*filter_item), GFP_KERNEL); + if (!filter_item) + goto fail_mem; + + list_add_tail(&filter_item->list, &filter_list); + + filter_item->filter = __alloc_filter(); + if (!filter_item->filter) + goto fail_mem; + filter = filter_item->filter; + + /* Can only fail on no memory */ + err = replace_filter_string(filter, filter_string); + if (err) + goto fail_mem; + + err = replace_preds(call, filter, ps, filter_string, false); + if (err) { + filter_disable(file); + parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0); + append_filter_err(ps, filter); + } else + event_set_filtered_flag(file); + /* + * Regardless of if this returned an error, we still + * replace the filter for the call. + */ + filter = event_filter(file); + event_set_filter(file, filter_item->filter); + filter_item->filter = filter; + + fail = false; } - err = -ENOMEM; + if (fail) + goto fail; + + /* + * The calls can still be using the old filters. + * Do a synchronize_sched() to ensure all calls are + * done with them before we free them. + */ + synchronize_sched(); + list_for_each_entry_safe(filter_item, tmp, &filter_list, list) { + __free_filter(filter_item->filter); + list_del(&filter_item->list); + kfree(filter_item); + } + return 0; + fail: + /* No call succeeded */ + list_for_each_entry_safe(filter_item, tmp, &filter_list, list) { + list_del(&filter_item->list); + kfree(filter_item); + } + parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0); + return -EINVAL; + fail_mem: + /* If any call succeeded, we still need to sync */ + if (!fail) + synchronize_sched(); + list_for_each_entry_safe(filter_item, tmp, &filter_list, list) { + __free_filter(filter_item->filter); + list_del(&filter_item->list); + kfree(filter_item); + } + return -ENOMEM; +} + +static int create_filter_start(char *filter_str, bool set_str, + struct filter_parse_state **psp, + struct event_filter **filterp) +{ + struct event_filter *filter; + struct filter_parse_state *ps = NULL; + int err = 0; + + WARN_ON_ONCE(*psp || *filterp); + + /* allocate everything, and if any fails, free all and fail */ + filter = __alloc_filter(); + if (filter && set_str) + err = replace_filter_string(filter, filter_str); + ps = kzalloc(sizeof(*ps), GFP_KERNEL); - if (!ps) - goto out_unlock; - filter_disable_preds(call); - replace_filter_string(call->filter, filter_string); + if (!filter || !ps || err) { + kfree(ps); + __free_filter(filter); + return -ENOMEM; + } + + /* we're committed to creating a new filter */ + *filterp = filter; + *psp = ps; - parse_init(ps, filter_ops, filter_string); + parse_init(ps, filter_ops, filter_str); err = filter_parse(ps); - if (err) { - append_filter_err(ps, call->filter); - goto out; + if (err && set_str) + append_filter_err(ps, filter); + return err; +} + +static void create_filter_finish(struct filter_parse_state *ps) +{ + if (ps) { + filter_opstack_clear(ps); + postfix_clear(ps); + kfree(ps); } +} - err = replace_preds(NULL, call, ps, filter_string); - if (err) - append_filter_err(ps, call->filter); +/** + * create_filter - create a filter for a ftrace_event_call + * @call: ftrace_event_call to create a filter for + * @filter_str: filter string + * @set_str: remember @filter_str and enable detailed error in filter + * @filterp: out param for created filter (always updated on return) + * + * Creates a filter for @call with @filter_str. If @set_str is %true, + * @filter_str is copied and recorded in the new filter. + * + * On success, returns 0 and *@filterp points to the new filter. On + * failure, returns -errno and *@filterp may point to %NULL or to a new + * filter. In the latter case, the returned filter contains error + * information if @set_str is %true and the caller is responsible for + * freeing it. + */ +static int create_filter(struct ftrace_event_call *call, + char *filter_str, bool set_str, + struct event_filter **filterp) +{ + struct event_filter *filter = NULL; + struct filter_parse_state *ps = NULL; + int err; -out: - filter_opstack_clear(ps); - postfix_clear(ps); - kfree(ps); -out_unlock: - mutex_unlock(&event_mutex); + err = create_filter_start(filter_str, set_str, &ps, &filter); + if (!err) { + err = replace_preds(call, filter, ps, filter_str, false); + if (err && set_str) + append_filter_err(ps, filter); + } + create_filter_finish(ps); + *filterp = filter; return err; } -int apply_subsystem_event_filter(struct event_subsystem *system, - char *filter_string) +int create_event_filter(struct ftrace_event_call *call, + char *filter_str, bool set_str, + struct event_filter **filterp) +{ + return create_filter(call, filter_str, set_str, filterp); +} + +/** + * create_system_filter - create a filter for an event_subsystem + * @system: event_subsystem to create a filter for + * @filter_str: filter string + * @filterp: out param for created filter (always updated on return) + * + * Identical to create_filter() except that it creates a subsystem filter + * and always remembers @filter_str. + */ +static int create_system_filter(struct event_subsystem *system, + struct trace_array *tr, + char *filter_str, struct event_filter **filterp) +{ + struct event_filter *filter = NULL; + struct filter_parse_state *ps = NULL; + int err; + + err = create_filter_start(filter_str, true, &ps, &filter); + if (!err) { + err = replace_system_preds(system, tr, ps, filter_str); + if (!err) { + /* System filters just show a default message */ + kfree(filter->filter_string); + filter->filter_string = NULL; + } else { + append_filter_err(ps, filter); + } + } + create_filter_finish(ps); + + *filterp = filter; + return err; +} + +/* caller must hold event_mutex */ +int apply_event_filter(struct ftrace_event_file *file, char *filter_string) { + struct ftrace_event_call *call = file->event_call; + struct event_filter *filter; int err; - struct filter_parse_state *ps; + if (!strcmp(strstrip(filter_string), "0")) { + filter_disable(file); + filter = event_filter(file); + + if (!filter) + return 0; + + event_clear_filter(file); + + /* Make sure the filter is not being used */ + synchronize_sched(); + __free_filter(filter); + + return 0; + } + + err = create_filter(call, filter_string, true, &filter); + + /* + * Always swap the call filter with the new filter + * even if there was an error. If there was an error + * in the filter, we disable the filter and show the error + * string + */ + if (filter) { + struct event_filter *tmp; + + tmp = event_filter(file); + if (!err) + event_set_filtered_flag(file); + else + filter_disable(file); + + event_set_filter(file, filter); + + if (tmp) { + /* Make sure the call is done with the filter */ + synchronize_sched(); + __free_filter(tmp); + } + } + + return err; +} + +int apply_subsystem_event_filter(struct ftrace_subsystem_dir *dir, + char *filter_string) +{ + struct event_subsystem *system = dir->subsystem; + struct trace_array *tr = dir->tr; + struct event_filter *filter; + int err = 0; mutex_lock(&event_mutex); + /* Make sure the system still has events */ + if (!dir->nr_events) { + err = -ENODEV; + goto out_unlock; + } + if (!strcmp(strstrip(filter_string), "0")) { - filter_free_subsystem_preds(system); + filter_free_subsystem_preds(system, tr); remove_filter_string(system->filter); - mutex_unlock(&event_mutex); - return 0; + filter = system->filter; + system->filter = NULL; + /* Ensure all filters are no longer used */ + synchronize_sched(); + filter_free_subsystem_filters(system, tr); + __free_filter(filter); + goto out_unlock; } - err = -ENOMEM; - ps = kzalloc(sizeof(*ps), GFP_KERNEL); - if (!ps) - goto out_unlock; + err = create_system_filter(system, tr, filter_string, &filter); + if (filter) { + /* + * No event actually uses the system filter + * we can free it without synchronize_sched(). + */ + __free_filter(system->filter); + system->filter = filter; + } +out_unlock: + mutex_unlock(&event_mutex); + + return err; +} - filter_free_subsystem_preds(system); - replace_filter_string(system->filter, filter_string); +#ifdef CONFIG_PERF_EVENTS - parse_init(ps, filter_ops, filter_string); - err = filter_parse(ps); - if (err) { - append_filter_err(ps, system->filter); - goto out; +void ftrace_profile_free_filter(struct perf_event *event) +{ + struct event_filter *filter = event->filter; + + event->filter = NULL; + __free_filter(filter); +} + +struct function_filter_data { + struct ftrace_ops *ops; + int first_filter; + int first_notrace; +}; + +#ifdef CONFIG_FUNCTION_TRACER +static char ** +ftrace_function_filter_re(char *buf, int len, int *count) +{ + char *str, *sep, **re; + + str = kstrndup(buf, len, GFP_KERNEL); + if (!str) + return NULL; + + /* + * The argv_split function takes white space + * as a separator, so convert ',' into spaces. + */ + while ((sep = strchr(str, ','))) + *sep = ' '; + + re = argv_split(GFP_KERNEL, str, count); + kfree(str); + return re; +} + +static int ftrace_function_set_regexp(struct ftrace_ops *ops, int filter, + int reset, char *re, int len) +{ + int ret; + + if (filter) + ret = ftrace_set_filter(ops, re, len, reset); + else + ret = ftrace_set_notrace(ops, re, len, reset); + + return ret; +} + +static int __ftrace_function_set_filter(int filter, char *buf, int len, + struct function_filter_data *data) +{ + int i, re_cnt, ret = -EINVAL; + int *reset; + char **re; + + reset = filter ? &data->first_filter : &data->first_notrace; + + /* + * The 'ip' field could have multiple filters set, separated + * either by space or comma. We first cut the filter and apply + * all pieces separatelly. + */ + re = ftrace_function_filter_re(buf, len, &re_cnt); + if (!re) + return -EINVAL; + + for (i = 0; i < re_cnt; i++) { + ret = ftrace_function_set_regexp(data->ops, filter, *reset, + re[i], strlen(re[i])); + if (ret) + break; + + if (*reset) + *reset = 0; } - err = replace_preds(system, NULL, ps, filter_string); + argv_free(re); + return ret; +} + +static int ftrace_function_check_pred(struct filter_pred *pred, int leaf) +{ + struct ftrace_event_field *field = pred->field; + + if (leaf) { + /* + * Check the leaf predicate for function trace, verify: + * - only '==' and '!=' is used + * - the 'ip' field is used + */ + if ((pred->op != OP_EQ) && (pred->op != OP_NE)) + return -EINVAL; + + if (strcmp(field->name, "ip")) + return -EINVAL; + } else { + /* + * Check the non leaf predicate for function trace, verify: + * - only '||' is used + */ + if (pred->op != OP_OR) + return -EINVAL; + } + + return 0; +} + +static int ftrace_function_set_filter_cb(enum move_type move, + struct filter_pred *pred, + int *err, void *data) +{ + /* Checking the node is valid for function trace. */ + if ((move != MOVE_DOWN) || + (pred->left != FILTER_PRED_INVALID)) { + *err = ftrace_function_check_pred(pred, 0); + } else { + *err = ftrace_function_check_pred(pred, 1); + if (*err) + return WALK_PRED_ABORT; + + *err = __ftrace_function_set_filter(pred->op == OP_EQ, + pred->regex.pattern, + pred->regex.len, + data); + } + + return (*err) ? WALK_PRED_ABORT : WALK_PRED_DEFAULT; +} + +static int ftrace_function_set_filter(struct perf_event *event, + struct event_filter *filter) +{ + struct function_filter_data data = { + .first_filter = 1, + .first_notrace = 1, + .ops = &event->ftrace_ops, + }; + + return walk_pred_tree(filter->preds, filter->root, + ftrace_function_set_filter_cb, &data); +} +#else +static int ftrace_function_set_filter(struct perf_event *event, + struct event_filter *filter) +{ + return -ENODEV; +} +#endif /* CONFIG_FUNCTION_TRACER */ + +int ftrace_profile_set_filter(struct perf_event *event, int event_id, + char *filter_str) +{ + int err; + struct event_filter *filter; + struct ftrace_event_call *call; + + mutex_lock(&event_mutex); + + call = event->tp_event; + + err = -EINVAL; + if (!call) + goto out_unlock; + + err = -EEXIST; + if (event->filter) + goto out_unlock; + + err = create_filter(call, filter_str, false, &filter); if (err) - append_filter_err(ps, system->filter); + goto free_filter; + + if (ftrace_event_is_function(call)) + err = ftrace_function_set_filter(event, filter); + else + event->filter = filter; + +free_filter: + if (err || ftrace_event_is_function(call)) + __free_filter(filter); -out: - filter_opstack_clear(ps); - postfix_clear(ps); - kfree(ps); out_unlock: mutex_unlock(&event_mutex); return err; } +#endif /* CONFIG_PERF_EVENTS */ + +#ifdef CONFIG_FTRACE_STARTUP_TEST + +#include <linux/types.h> +#include <linux/tracepoint.h> + +#define CREATE_TRACE_POINTS +#include "trace_events_filter_test.h" + +#define DATA_REC(m, va, vb, vc, vd, ve, vf, vg, vh, nvisit) \ +{ \ + .filter = FILTER, \ + .rec = { .a = va, .b = vb, .c = vc, .d = vd, \ + .e = ve, .f = vf, .g = vg, .h = vh }, \ + .match = m, \ + .not_visited = nvisit, \ +} +#define YES 1 +#define NO 0 + +static struct test_filter_data_t { + char *filter; + struct ftrace_raw_ftrace_test_filter rec; + int match; + char *not_visited; +} test_filter_data[] = { +#define FILTER "a == 1 && b == 1 && c == 1 && d == 1 && " \ + "e == 1 && f == 1 && g == 1 && h == 1" + DATA_REC(YES, 1, 1, 1, 1, 1, 1, 1, 1, ""), + DATA_REC(NO, 0, 1, 1, 1, 1, 1, 1, 1, "bcdefgh"), + DATA_REC(NO, 1, 1, 1, 1, 1, 1, 1, 0, ""), +#undef FILTER +#define FILTER "a == 1 || b == 1 || c == 1 || d == 1 || " \ + "e == 1 || f == 1 || g == 1 || h == 1" + DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 0, ""), + DATA_REC(YES, 0, 0, 0, 0, 0, 0, 0, 1, ""), + DATA_REC(YES, 1, 0, 0, 0, 0, 0, 0, 0, "bcdefgh"), +#undef FILTER +#define FILTER "(a == 1 || b == 1) && (c == 1 || d == 1) && " \ + "(e == 1 || f == 1) && (g == 1 || h == 1)" + DATA_REC(NO, 0, 0, 1, 1, 1, 1, 1, 1, "dfh"), + DATA_REC(YES, 0, 1, 0, 1, 0, 1, 0, 1, ""), + DATA_REC(YES, 1, 0, 1, 0, 0, 1, 0, 1, "bd"), + DATA_REC(NO, 1, 0, 1, 0, 0, 1, 0, 0, "bd"), +#undef FILTER +#define FILTER "(a == 1 && b == 1) || (c == 1 && d == 1) || " \ + "(e == 1 && f == 1) || (g == 1 && h == 1)" + DATA_REC(YES, 1, 0, 1, 1, 1, 1, 1, 1, "efgh"), + DATA_REC(YES, 0, 0, 0, 0, 0, 0, 1, 1, ""), + DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 1, ""), +#undef FILTER +#define FILTER "(a == 1 && b == 1) && (c == 1 && d == 1) && " \ + "(e == 1 && f == 1) || (g == 1 && h == 1)" + DATA_REC(YES, 1, 1, 1, 1, 1, 1, 0, 0, "gh"), + DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 1, ""), + DATA_REC(YES, 1, 1, 1, 1, 1, 0, 1, 1, ""), +#undef FILTER +#define FILTER "((a == 1 || b == 1) || (c == 1 || d == 1) || " \ + "(e == 1 || f == 1)) && (g == 1 || h == 1)" + DATA_REC(YES, 1, 1, 1, 1, 1, 1, 0, 1, "bcdef"), + DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 0, ""), + DATA_REC(YES, 1, 1, 1, 1, 1, 0, 1, 1, "h"), +#undef FILTER +#define FILTER "((((((((a == 1) && (b == 1)) || (c == 1)) && (d == 1)) || " \ + "(e == 1)) && (f == 1)) || (g == 1)) && (h == 1))" + DATA_REC(YES, 1, 1, 1, 1, 1, 1, 1, 1, "ceg"), + DATA_REC(NO, 0, 1, 0, 1, 0, 1, 0, 1, ""), + DATA_REC(NO, 1, 0, 1, 0, 1, 0, 1, 0, ""), +#undef FILTER +#define FILTER "((((((((a == 1) || (b == 1)) && (c == 1)) || (d == 1)) && " \ + "(e == 1)) || (f == 1)) && (g == 1)) || (h == 1))" + DATA_REC(YES, 1, 1, 1, 1, 1, 1, 1, 1, "bdfh"), + DATA_REC(YES, 0, 1, 0, 1, 0, 1, 0, 1, ""), + DATA_REC(YES, 1, 0, 1, 0, 1, 0, 1, 0, "bdfh"), +}; + +#undef DATA_REC +#undef FILTER +#undef YES +#undef NO + +#define DATA_CNT (sizeof(test_filter_data)/sizeof(struct test_filter_data_t)) + +static int test_pred_visited; + +static int test_pred_visited_fn(struct filter_pred *pred, void *event) +{ + struct ftrace_event_field *field = pred->field; + + test_pred_visited = 1; + printk(KERN_INFO "\npred visited %s\n", field->name); + return 1; +} + +static int test_walk_pred_cb(enum move_type move, struct filter_pred *pred, + int *err, void *data) +{ + char *fields = data; + + if ((move == MOVE_DOWN) && + (pred->left == FILTER_PRED_INVALID)) { + struct ftrace_event_field *field = pred->field; + + if (!field) { + WARN(1, "all leafs should have field defined"); + return WALK_PRED_DEFAULT; + } + if (!strchr(fields, *field->name)) + return WALK_PRED_DEFAULT; + + WARN_ON(!pred->fn); + pred->fn = test_pred_visited_fn; + } + return WALK_PRED_DEFAULT; +} + +static __init int ftrace_test_event_filter(void) +{ + int i; + + printk(KERN_INFO "Testing ftrace filter: "); + + for (i = 0; i < DATA_CNT; i++) { + struct event_filter *filter = NULL; + struct test_filter_data_t *d = &test_filter_data[i]; + int err; + + err = create_filter(&event_ftrace_test_filter, d->filter, + false, &filter); + if (err) { + printk(KERN_INFO + "Failed to get filter for '%s', err %d\n", + d->filter, err); + __free_filter(filter); + break; + } + + /* + * The preemption disabling is not really needed for self + * tests, but the rcu dereference will complain without it. + */ + preempt_disable(); + if (*d->not_visited) + walk_pred_tree(filter->preds, filter->root, + test_walk_pred_cb, + d->not_visited); + + test_pred_visited = 0; + err = filter_match_preds(filter, &d->rec); + preempt_enable(); + + __free_filter(filter); + + if (test_pred_visited) { + printk(KERN_INFO + "Failed, unwanted pred visited for filter %s\n", + d->filter); + break; + } + + if (err != d->match) { + printk(KERN_INFO + "Failed to match filter '%s', expected %d\n", + d->filter, d->match); + break; + } + } + + if (i == DATA_CNT) + printk(KERN_CONT "OK\n"); + + return 0; +} + +late_initcall(ftrace_test_event_filter); + +#endif /* CONFIG_FTRACE_STARTUP_TEST */ diff --git a/kernel/trace/trace_events_filter_test.h b/kernel/trace/trace_events_filter_test.h new file mode 100644 index 00000000000..bfd4dba0d60 --- /dev/null +++ b/kernel/trace/trace_events_filter_test.h @@ -0,0 +1,50 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM test + +#if !defined(_TRACE_TEST_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_TEST_H + +#include <linux/tracepoint.h> + +TRACE_EVENT(ftrace_test_filter, + + TP_PROTO(int a, int b, int c, int d, int e, int f, int g, int h), + + TP_ARGS(a, b, c, d, e, f, g, h), + + TP_STRUCT__entry( + __field(int, a) + __field(int, b) + __field(int, c) + __field(int, d) + __field(int, e) + __field(int, f) + __field(int, g) + __field(int, h) + ), + + TP_fast_assign( + __entry->a = a; + __entry->b = b; + __entry->c = c; + __entry->d = d; + __entry->e = e; + __entry->f = f; + __entry->g = g; + __entry->h = h; + ), + + TP_printk("a %d, b %d, c %d, d %d, e %d, f %d, g %d, h %d", + __entry->a, __entry->b, __entry->c, __entry->d, + __entry->e, __entry->f, __entry->g, __entry->h) +); + +#endif /* _TRACE_TEST_H || TRACE_HEADER_MULTI_READ */ + +#undef TRACE_INCLUDE_PATH +#undef TRACE_INCLUDE_FILE +#define TRACE_INCLUDE_PATH . +#define TRACE_INCLUDE_FILE trace_events_filter_test + +/* This part must be outside protection */ +#include <trace/define_trace.h> diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c new file mode 100644 index 00000000000..4747b476a03 --- /dev/null +++ b/kernel/trace/trace_events_trigger.c @@ -0,0 +1,1437 @@ +/* + * trace_events_trigger - trace event triggers + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright (C) 2013 Tom Zanussi <tom.zanussi@linux.intel.com> + */ + +#include <linux/module.h> +#include <linux/ctype.h> +#include <linux/mutex.h> +#include <linux/slab.h> + +#include "trace.h" + +static LIST_HEAD(trigger_commands); +static DEFINE_MUTEX(trigger_cmd_mutex); + +static void +trigger_data_free(struct event_trigger_data *data) +{ + if (data->cmd_ops->set_filter) + data->cmd_ops->set_filter(NULL, data, NULL); + + synchronize_sched(); /* make sure current triggers exit before free */ + kfree(data); +} + +/** + * event_triggers_call - Call triggers associated with a trace event + * @file: The ftrace_event_file associated with the event + * @rec: The trace entry for the event, NULL for unconditional invocation + * + * For each trigger associated with an event, invoke the trigger + * function registered with the associated trigger command. If rec is + * non-NULL, it means that the trigger requires further processing and + * shouldn't be unconditionally invoked. If rec is non-NULL and the + * trigger has a filter associated with it, rec will checked against + * the filter and if the record matches the trigger will be invoked. + * If the trigger is a 'post_trigger', meaning it shouldn't be invoked + * in any case until the current event is written, the trigger + * function isn't invoked but the bit associated with the deferred + * trigger is set in the return value. + * + * Returns an enum event_trigger_type value containing a set bit for + * any trigger that should be deferred, ETT_NONE if nothing to defer. + * + * Called from tracepoint handlers (with rcu_read_lock_sched() held). + * + * Return: an enum event_trigger_type value containing a set bit for + * any trigger that should be deferred, ETT_NONE if nothing to defer. + */ +enum event_trigger_type +event_triggers_call(struct ftrace_event_file *file, void *rec) +{ + struct event_trigger_data *data; + enum event_trigger_type tt = ETT_NONE; + struct event_filter *filter; + + if (list_empty(&file->triggers)) + return tt; + + list_for_each_entry_rcu(data, &file->triggers, list) { + if (!rec) { + data->ops->func(data); + continue; + } + filter = rcu_dereference_sched(data->filter); + if (filter && !filter_match_preds(filter, rec)) + continue; + if (data->cmd_ops->post_trigger) { + tt |= data->cmd_ops->trigger_type; + continue; + } + data->ops->func(data); + } + return tt; +} +EXPORT_SYMBOL_GPL(event_triggers_call); + +/** + * event_triggers_post_call - Call 'post_triggers' for a trace event + * @file: The ftrace_event_file associated with the event + * @tt: enum event_trigger_type containing a set bit for each trigger to invoke + * + * For each trigger associated with an event, invoke the trigger + * function registered with the associated trigger command, if the + * corresponding bit is set in the tt enum passed into this function. + * See @event_triggers_call for details on how those bits are set. + * + * Called from tracepoint handlers (with rcu_read_lock_sched() held). + */ +void +event_triggers_post_call(struct ftrace_event_file *file, + enum event_trigger_type tt) +{ + struct event_trigger_data *data; + + list_for_each_entry_rcu(data, &file->triggers, list) { + if (data->cmd_ops->trigger_type & tt) + data->ops->func(data); + } +} +EXPORT_SYMBOL_GPL(event_triggers_post_call); + +#define SHOW_AVAILABLE_TRIGGERS (void *)(1UL) + +static void *trigger_next(struct seq_file *m, void *t, loff_t *pos) +{ + struct ftrace_event_file *event_file = event_file_data(m->private); + + if (t == SHOW_AVAILABLE_TRIGGERS) + return NULL; + + return seq_list_next(t, &event_file->triggers, pos); +} + +static void *trigger_start(struct seq_file *m, loff_t *pos) +{ + struct ftrace_event_file *event_file; + + /* ->stop() is called even if ->start() fails */ + mutex_lock(&event_mutex); + event_file = event_file_data(m->private); + if (unlikely(!event_file)) + return ERR_PTR(-ENODEV); + + if (list_empty(&event_file->triggers)) + return *pos == 0 ? SHOW_AVAILABLE_TRIGGERS : NULL; + + return seq_list_start(&event_file->triggers, *pos); +} + +static void trigger_stop(struct seq_file *m, void *t) +{ + mutex_unlock(&event_mutex); +} + +static int trigger_show(struct seq_file *m, void *v) +{ + struct event_trigger_data *data; + struct event_command *p; + + if (v == SHOW_AVAILABLE_TRIGGERS) { + seq_puts(m, "# Available triggers:\n"); + seq_putc(m, '#'); + mutex_lock(&trigger_cmd_mutex); + list_for_each_entry_reverse(p, &trigger_commands, list) + seq_printf(m, " %s", p->name); + seq_putc(m, '\n'); + mutex_unlock(&trigger_cmd_mutex); + return 0; + } + + data = list_entry(v, struct event_trigger_data, list); + data->ops->print(m, data->ops, data); + + return 0; +} + +static const struct seq_operations event_triggers_seq_ops = { + .start = trigger_start, + .next = trigger_next, + .stop = trigger_stop, + .show = trigger_show, +}; + +static int event_trigger_regex_open(struct inode *inode, struct file *file) +{ + int ret = 0; + + mutex_lock(&event_mutex); + + if (unlikely(!event_file_data(file))) { + mutex_unlock(&event_mutex); + return -ENODEV; + } + + if (file->f_mode & FMODE_READ) { + ret = seq_open(file, &event_triggers_seq_ops); + if (!ret) { + struct seq_file *m = file->private_data; + m->private = file; + } + } + + mutex_unlock(&event_mutex); + + return ret; +} + +static int trigger_process_regex(struct ftrace_event_file *file, char *buff) +{ + char *command, *next = buff; + struct event_command *p; + int ret = -EINVAL; + + command = strsep(&next, ": \t"); + command = (command[0] != '!') ? command : command + 1; + + mutex_lock(&trigger_cmd_mutex); + list_for_each_entry(p, &trigger_commands, list) { + if (strcmp(p->name, command) == 0) { + ret = p->func(p, file, buff, command, next); + goto out_unlock; + } + } + out_unlock: + mutex_unlock(&trigger_cmd_mutex); + + return ret; +} + +static ssize_t event_trigger_regex_write(struct file *file, + const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + struct ftrace_event_file *event_file; + ssize_t ret; + char *buf; + + if (!cnt) + return 0; + + if (cnt >= PAGE_SIZE) + return -EINVAL; + + buf = (char *)__get_free_page(GFP_TEMPORARY); + if (!buf) + return -ENOMEM; + + if (copy_from_user(buf, ubuf, cnt)) { + free_page((unsigned long)buf); + return -EFAULT; + } + buf[cnt] = '\0'; + strim(buf); + + mutex_lock(&event_mutex); + event_file = event_file_data(file); + if (unlikely(!event_file)) { + mutex_unlock(&event_mutex); + free_page((unsigned long)buf); + return -ENODEV; + } + ret = trigger_process_regex(event_file, buf); + mutex_unlock(&event_mutex); + + free_page((unsigned long)buf); + if (ret < 0) + goto out; + + *ppos += cnt; + ret = cnt; + out: + return ret; +} + +static int event_trigger_regex_release(struct inode *inode, struct file *file) +{ + mutex_lock(&event_mutex); + + if (file->f_mode & FMODE_READ) + seq_release(inode, file); + + mutex_unlock(&event_mutex); + + return 0; +} + +static ssize_t +event_trigger_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + return event_trigger_regex_write(filp, ubuf, cnt, ppos); +} + +static int +event_trigger_open(struct inode *inode, struct file *filp) +{ + return event_trigger_regex_open(inode, filp); +} + +static int +event_trigger_release(struct inode *inode, struct file *file) +{ + return event_trigger_regex_release(inode, file); +} + +const struct file_operations event_trigger_fops = { + .open = event_trigger_open, + .read = seq_read, + .write = event_trigger_write, + .llseek = tracing_lseek, + .release = event_trigger_release, +}; + +/* + * Currently we only register event commands from __init, so mark this + * __init too. + */ +static __init int register_event_command(struct event_command *cmd) +{ + struct event_command *p; + int ret = 0; + + mutex_lock(&trigger_cmd_mutex); + list_for_each_entry(p, &trigger_commands, list) { + if (strcmp(cmd->name, p->name) == 0) { + ret = -EBUSY; + goto out_unlock; + } + } + list_add(&cmd->list, &trigger_commands); + out_unlock: + mutex_unlock(&trigger_cmd_mutex); + + return ret; +} + +/* + * Currently we only unregister event commands from __init, so mark + * this __init too. + */ +static __init int unregister_event_command(struct event_command *cmd) +{ + struct event_command *p, *n; + int ret = -ENODEV; + + mutex_lock(&trigger_cmd_mutex); + list_for_each_entry_safe(p, n, &trigger_commands, list) { + if (strcmp(cmd->name, p->name) == 0) { + ret = 0; + list_del_init(&p->list); + goto out_unlock; + } + } + out_unlock: + mutex_unlock(&trigger_cmd_mutex); + + return ret; +} + +/** + * event_trigger_print - Generic event_trigger_ops @print implementation + * @name: The name of the event trigger + * @m: The seq_file being printed to + * @data: Trigger-specific data + * @filter_str: filter_str to print, if present + * + * Common implementation for event triggers to print themselves. + * + * Usually wrapped by a function that simply sets the @name of the + * trigger command and then invokes this. + * + * Return: 0 on success, errno otherwise + */ +static int +event_trigger_print(const char *name, struct seq_file *m, + void *data, char *filter_str) +{ + long count = (long)data; + + seq_printf(m, "%s", name); + + if (count == -1) + seq_puts(m, ":unlimited"); + else + seq_printf(m, ":count=%ld", count); + + if (filter_str) + seq_printf(m, " if %s\n", filter_str); + else + seq_puts(m, "\n"); + + return 0; +} + +/** + * event_trigger_init - Generic event_trigger_ops @init implementation + * @ops: The trigger ops associated with the trigger + * @data: Trigger-specific data + * + * Common implementation of event trigger initialization. + * + * Usually used directly as the @init method in event trigger + * implementations. + * + * Return: 0 on success, errno otherwise + */ +static int +event_trigger_init(struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + data->ref++; + return 0; +} + +/** + * event_trigger_free - Generic event_trigger_ops @free implementation + * @ops: The trigger ops associated with the trigger + * @data: Trigger-specific data + * + * Common implementation of event trigger de-initialization. + * + * Usually used directly as the @free method in event trigger + * implementations. + */ +static void +event_trigger_free(struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + if (WARN_ON_ONCE(data->ref <= 0)) + return; + + data->ref--; + if (!data->ref) + trigger_data_free(data); +} + +static int trace_event_trigger_enable_disable(struct ftrace_event_file *file, + int trigger_enable) +{ + int ret = 0; + + if (trigger_enable) { + if (atomic_inc_return(&file->tm_ref) > 1) + return ret; + set_bit(FTRACE_EVENT_FL_TRIGGER_MODE_BIT, &file->flags); + ret = trace_event_enable_disable(file, 1, 1); + } else { + if (atomic_dec_return(&file->tm_ref) > 0) + return ret; + clear_bit(FTRACE_EVENT_FL_TRIGGER_MODE_BIT, &file->flags); + ret = trace_event_enable_disable(file, 0, 1); + } + + return ret; +} + +/** + * clear_event_triggers - Clear all triggers associated with a trace array + * @tr: The trace array to clear + * + * For each trigger, the triggering event has its tm_ref decremented + * via trace_event_trigger_enable_disable(), and any associated event + * (in the case of enable/disable_event triggers) will have its sm_ref + * decremented via free()->trace_event_enable_disable(). That + * combination effectively reverses the soft-mode/trigger state added + * by trigger registration. + * + * Must be called with event_mutex held. + */ +void +clear_event_triggers(struct trace_array *tr) +{ + struct ftrace_event_file *file; + + list_for_each_entry(file, &tr->events, list) { + struct event_trigger_data *data; + list_for_each_entry_rcu(data, &file->triggers, list) { + trace_event_trigger_enable_disable(file, 0); + if (data->ops->free) + data->ops->free(data->ops, data); + } + } +} + +/** + * update_cond_flag - Set or reset the TRIGGER_COND bit + * @file: The ftrace_event_file associated with the event + * + * If an event has triggers and any of those triggers has a filter or + * a post_trigger, trigger invocation needs to be deferred until after + * the current event has logged its data, and the event should have + * its TRIGGER_COND bit set, otherwise the TRIGGER_COND bit should be + * cleared. + */ +static void update_cond_flag(struct ftrace_event_file *file) +{ + struct event_trigger_data *data; + bool set_cond = false; + + list_for_each_entry_rcu(data, &file->triggers, list) { + if (data->filter || data->cmd_ops->post_trigger) { + set_cond = true; + break; + } + } + + if (set_cond) + set_bit(FTRACE_EVENT_FL_TRIGGER_COND_BIT, &file->flags); + else + clear_bit(FTRACE_EVENT_FL_TRIGGER_COND_BIT, &file->flags); +} + +/** + * register_trigger - Generic event_command @reg implementation + * @glob: The raw string used to register the trigger + * @ops: The trigger ops associated with the trigger + * @data: Trigger-specific data to associate with the trigger + * @file: The ftrace_event_file associated with the event + * + * Common implementation for event trigger registration. + * + * Usually used directly as the @reg method in event command + * implementations. + * + * Return: 0 on success, errno otherwise + */ +static int register_trigger(char *glob, struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct ftrace_event_file *file) +{ + struct event_trigger_data *test; + int ret = 0; + + list_for_each_entry_rcu(test, &file->triggers, list) { + if (test->cmd_ops->trigger_type == data->cmd_ops->trigger_type) { + ret = -EEXIST; + goto out; + } + } + + if (data->ops->init) { + ret = data->ops->init(data->ops, data); + if (ret < 0) + goto out; + } + + list_add_rcu(&data->list, &file->triggers); + ret++; + + if (trace_event_trigger_enable_disable(file, 1) < 0) { + list_del_rcu(&data->list); + ret--; + } + update_cond_flag(file); +out: + return ret; +} + +/** + * unregister_trigger - Generic event_command @unreg implementation + * @glob: The raw string used to register the trigger + * @ops: The trigger ops associated with the trigger + * @test: Trigger-specific data used to find the trigger to remove + * @file: The ftrace_event_file associated with the event + * + * Common implementation for event trigger unregistration. + * + * Usually used directly as the @unreg method in event command + * implementations. + */ +static void unregister_trigger(char *glob, struct event_trigger_ops *ops, + struct event_trigger_data *test, + struct ftrace_event_file *file) +{ + struct event_trigger_data *data; + bool unregistered = false; + + list_for_each_entry_rcu(data, &file->triggers, list) { + if (data->cmd_ops->trigger_type == test->cmd_ops->trigger_type) { + unregistered = true; + list_del_rcu(&data->list); + update_cond_flag(file); + trace_event_trigger_enable_disable(file, 0); + break; + } + } + + if (unregistered && data->ops->free) + data->ops->free(data->ops, data); +} + +/** + * event_trigger_callback - Generic event_command @func implementation + * @cmd_ops: The command ops, used for trigger registration + * @file: The ftrace_event_file associated with the event + * @glob: The raw string used to register the trigger + * @cmd: The cmd portion of the string used to register the trigger + * @param: The params portion of the string used to register the trigger + * + * Common implementation for event command parsing and trigger + * instantiation. + * + * Usually used directly as the @func method in event command + * implementations. + * + * Return: 0 on success, errno otherwise + */ +static int +event_trigger_callback(struct event_command *cmd_ops, + struct ftrace_event_file *file, + char *glob, char *cmd, char *param) +{ + struct event_trigger_data *trigger_data; + struct event_trigger_ops *trigger_ops; + char *trigger = NULL; + char *number; + int ret; + + /* separate the trigger from the filter (t:n [if filter]) */ + if (param && isdigit(param[0])) + trigger = strsep(¶m, " \t"); + + trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); + + ret = -ENOMEM; + trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); + if (!trigger_data) + goto out; + + trigger_data->count = -1; + trigger_data->ops = trigger_ops; + trigger_data->cmd_ops = cmd_ops; + INIT_LIST_HEAD(&trigger_data->list); + + if (glob[0] == '!') { + cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); + kfree(trigger_data); + ret = 0; + goto out; + } + + if (trigger) { + number = strsep(&trigger, ":"); + + ret = -EINVAL; + if (!strlen(number)) + goto out_free; + + /* + * We use the callback data field (which is a pointer) + * as our counter. + */ + ret = kstrtoul(number, 0, &trigger_data->count); + if (ret) + goto out_free; + } + + if (!param) /* if param is non-empty, it's supposed to be a filter */ + goto out_reg; + + if (!cmd_ops->set_filter) + goto out_reg; + + ret = cmd_ops->set_filter(param, trigger_data, file); + if (ret < 0) + goto out_free; + + out_reg: + ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); + /* + * The above returns on success the # of functions enabled, + * but if it didn't find any functions it returns zero. + * Consider no functions a failure too. + */ + if (!ret) { + ret = -ENOENT; + goto out_free; + } else if (ret < 0) + goto out_free; + ret = 0; + out: + return ret; + + out_free: + if (cmd_ops->set_filter) + cmd_ops->set_filter(NULL, trigger_data, NULL); + kfree(trigger_data); + goto out; +} + +/** + * set_trigger_filter - Generic event_command @set_filter implementation + * @filter_str: The filter string for the trigger, NULL to remove filter + * @trigger_data: Trigger-specific data + * @file: The ftrace_event_file associated with the event + * + * Common implementation for event command filter parsing and filter + * instantiation. + * + * Usually used directly as the @set_filter method in event command + * implementations. + * + * Also used to remove a filter (if filter_str = NULL). + * + * Return: 0 on success, errno otherwise + */ +static int set_trigger_filter(char *filter_str, + struct event_trigger_data *trigger_data, + struct ftrace_event_file *file) +{ + struct event_trigger_data *data = trigger_data; + struct event_filter *filter = NULL, *tmp; + int ret = -EINVAL; + char *s; + + if (!filter_str) /* clear the current filter */ + goto assign; + + s = strsep(&filter_str, " \t"); + + if (!strlen(s) || strcmp(s, "if") != 0) + goto out; + + if (!filter_str) + goto out; + + /* The filter is for the 'trigger' event, not the triggered event */ + ret = create_event_filter(file->event_call, filter_str, false, &filter); + if (ret) + goto out; + assign: + tmp = rcu_access_pointer(data->filter); + + rcu_assign_pointer(data->filter, filter); + + if (tmp) { + /* Make sure the call is done with the filter */ + synchronize_sched(); + free_event_filter(tmp); + } + + kfree(data->filter_str); + data->filter_str = NULL; + + if (filter_str) { + data->filter_str = kstrdup(filter_str, GFP_KERNEL); + if (!data->filter_str) { + free_event_filter(rcu_access_pointer(data->filter)); + data->filter = NULL; + ret = -ENOMEM; + } + } + out: + return ret; +} + +static void +traceon_trigger(struct event_trigger_data *data) +{ + if (tracing_is_on()) + return; + + tracing_on(); +} + +static void +traceon_count_trigger(struct event_trigger_data *data) +{ + if (tracing_is_on()) + return; + + if (!data->count) + return; + + if (data->count != -1) + (data->count)--; + + tracing_on(); +} + +static void +traceoff_trigger(struct event_trigger_data *data) +{ + if (!tracing_is_on()) + return; + + tracing_off(); +} + +static void +traceoff_count_trigger(struct event_trigger_data *data) +{ + if (!tracing_is_on()) + return; + + if (!data->count) + return; + + if (data->count != -1) + (data->count)--; + + tracing_off(); +} + +static int +traceon_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + return event_trigger_print("traceon", m, (void *)data->count, + data->filter_str); +} + +static int +traceoff_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + return event_trigger_print("traceoff", m, (void *)data->count, + data->filter_str); +} + +static struct event_trigger_ops traceon_trigger_ops = { + .func = traceon_trigger, + .print = traceon_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops traceon_count_trigger_ops = { + .func = traceon_count_trigger, + .print = traceon_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops traceoff_trigger_ops = { + .func = traceoff_trigger, + .print = traceoff_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops traceoff_count_trigger_ops = { + .func = traceoff_count_trigger, + .print = traceoff_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops * +onoff_get_trigger_ops(char *cmd, char *param) +{ + struct event_trigger_ops *ops; + + /* we register both traceon and traceoff to this callback */ + if (strcmp(cmd, "traceon") == 0) + ops = param ? &traceon_count_trigger_ops : + &traceon_trigger_ops; + else + ops = param ? &traceoff_count_trigger_ops : + &traceoff_trigger_ops; + + return ops; +} + +static struct event_command trigger_traceon_cmd = { + .name = "traceon", + .trigger_type = ETT_TRACE_ONOFF, + .func = event_trigger_callback, + .reg = register_trigger, + .unreg = unregister_trigger, + .get_trigger_ops = onoff_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static struct event_command trigger_traceoff_cmd = { + .name = "traceoff", + .trigger_type = ETT_TRACE_ONOFF, + .func = event_trigger_callback, + .reg = register_trigger, + .unreg = unregister_trigger, + .get_trigger_ops = onoff_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +#ifdef CONFIG_TRACER_SNAPSHOT +static void +snapshot_trigger(struct event_trigger_data *data) +{ + tracing_snapshot(); +} + +static void +snapshot_count_trigger(struct event_trigger_data *data) +{ + if (!data->count) + return; + + if (data->count != -1) + (data->count)--; + + snapshot_trigger(data); +} + +static int +register_snapshot_trigger(char *glob, struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct ftrace_event_file *file) +{ + int ret = register_trigger(glob, ops, data, file); + + if (ret > 0 && tracing_alloc_snapshot() != 0) { + unregister_trigger(glob, ops, data, file); + ret = 0; + } + + return ret; +} + +static int +snapshot_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + return event_trigger_print("snapshot", m, (void *)data->count, + data->filter_str); +} + +static struct event_trigger_ops snapshot_trigger_ops = { + .func = snapshot_trigger, + .print = snapshot_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops snapshot_count_trigger_ops = { + .func = snapshot_count_trigger, + .print = snapshot_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops * +snapshot_get_trigger_ops(char *cmd, char *param) +{ + return param ? &snapshot_count_trigger_ops : &snapshot_trigger_ops; +} + +static struct event_command trigger_snapshot_cmd = { + .name = "snapshot", + .trigger_type = ETT_SNAPSHOT, + .func = event_trigger_callback, + .reg = register_snapshot_trigger, + .unreg = unregister_trigger, + .get_trigger_ops = snapshot_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static __init int register_trigger_snapshot_cmd(void) +{ + int ret; + + ret = register_event_command(&trigger_snapshot_cmd); + WARN_ON(ret < 0); + + return ret; +} +#else +static __init int register_trigger_snapshot_cmd(void) { return 0; } +#endif /* CONFIG_TRACER_SNAPSHOT */ + +#ifdef CONFIG_STACKTRACE +/* + * Skip 3: + * stacktrace_trigger() + * event_triggers_post_call() + * ftrace_raw_event_xxx() + */ +#define STACK_SKIP 3 + +static void +stacktrace_trigger(struct event_trigger_data *data) +{ + trace_dump_stack(STACK_SKIP); +} + +static void +stacktrace_count_trigger(struct event_trigger_data *data) +{ + if (!data->count) + return; + + if (data->count != -1) + (data->count)--; + + stacktrace_trigger(data); +} + +static int +stacktrace_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + return event_trigger_print("stacktrace", m, (void *)data->count, + data->filter_str); +} + +static struct event_trigger_ops stacktrace_trigger_ops = { + .func = stacktrace_trigger, + .print = stacktrace_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops stacktrace_count_trigger_ops = { + .func = stacktrace_count_trigger, + .print = stacktrace_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops * +stacktrace_get_trigger_ops(char *cmd, char *param) +{ + return param ? &stacktrace_count_trigger_ops : &stacktrace_trigger_ops; +} + +static struct event_command trigger_stacktrace_cmd = { + .name = "stacktrace", + .trigger_type = ETT_STACKTRACE, + .post_trigger = true, + .func = event_trigger_callback, + .reg = register_trigger, + .unreg = unregister_trigger, + .get_trigger_ops = stacktrace_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static __init int register_trigger_stacktrace_cmd(void) +{ + int ret; + + ret = register_event_command(&trigger_stacktrace_cmd); + WARN_ON(ret < 0); + + return ret; +} +#else +static __init int register_trigger_stacktrace_cmd(void) { return 0; } +#endif /* CONFIG_STACKTRACE */ + +static __init void unregister_trigger_traceon_traceoff_cmds(void) +{ + unregister_event_command(&trigger_traceon_cmd); + unregister_event_command(&trigger_traceoff_cmd); +} + +/* Avoid typos */ +#define ENABLE_EVENT_STR "enable_event" +#define DISABLE_EVENT_STR "disable_event" + +struct enable_trigger_data { + struct ftrace_event_file *file; + bool enable; +}; + +static void +event_enable_trigger(struct event_trigger_data *data) +{ + struct enable_trigger_data *enable_data = data->private_data; + + if (enable_data->enable) + clear_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); + else + set_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); +} + +static void +event_enable_count_trigger(struct event_trigger_data *data) +{ + struct enable_trigger_data *enable_data = data->private_data; + + if (!data->count) + return; + + /* Skip if the event is in a state we want to switch to */ + if (enable_data->enable == !(enable_data->file->flags & FTRACE_EVENT_FL_SOFT_DISABLED)) + return; + + if (data->count != -1) + (data->count)--; + + event_enable_trigger(data); +} + +static int +event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + struct enable_trigger_data *enable_data = data->private_data; + + seq_printf(m, "%s:%s:%s", + enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR, + enable_data->file->event_call->class->system, + ftrace_event_name(enable_data->file->event_call)); + + if (data->count == -1) + seq_puts(m, ":unlimited"); + else + seq_printf(m, ":count=%ld", data->count); + + if (data->filter_str) + seq_printf(m, " if %s\n", data->filter_str); + else + seq_puts(m, "\n"); + + return 0; +} + +static void +event_enable_trigger_free(struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + struct enable_trigger_data *enable_data = data->private_data; + + if (WARN_ON_ONCE(data->ref <= 0)) + return; + + data->ref--; + if (!data->ref) { + /* Remove the SOFT_MODE flag */ + trace_event_enable_disable(enable_data->file, 0, 1); + module_put(enable_data->file->event_call->mod); + trigger_data_free(data); + kfree(enable_data); + } +} + +static struct event_trigger_ops event_enable_trigger_ops = { + .func = event_enable_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static struct event_trigger_ops event_enable_count_trigger_ops = { + .func = event_enable_count_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static struct event_trigger_ops event_disable_trigger_ops = { + .func = event_enable_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static struct event_trigger_ops event_disable_count_trigger_ops = { + .func = event_enable_count_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static int +event_enable_trigger_func(struct event_command *cmd_ops, + struct ftrace_event_file *file, + char *glob, char *cmd, char *param) +{ + struct ftrace_event_file *event_enable_file; + struct enable_trigger_data *enable_data; + struct event_trigger_data *trigger_data; + struct event_trigger_ops *trigger_ops; + struct trace_array *tr = file->tr; + const char *system; + const char *event; + char *trigger; + char *number; + bool enable; + int ret; + + if (!param) + return -EINVAL; + + /* separate the trigger from the filter (s:e:n [if filter]) */ + trigger = strsep(¶m, " \t"); + if (!trigger) + return -EINVAL; + + system = strsep(&trigger, ":"); + if (!trigger) + return -EINVAL; + + event = strsep(&trigger, ":"); + + ret = -EINVAL; + event_enable_file = find_event_file(tr, system, event); + if (!event_enable_file) + goto out; + + enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; + + trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); + + ret = -ENOMEM; + trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); + if (!trigger_data) + goto out; + + enable_data = kzalloc(sizeof(*enable_data), GFP_KERNEL); + if (!enable_data) { + kfree(trigger_data); + goto out; + } + + trigger_data->count = -1; + trigger_data->ops = trigger_ops; + trigger_data->cmd_ops = cmd_ops; + INIT_LIST_HEAD(&trigger_data->list); + RCU_INIT_POINTER(trigger_data->filter, NULL); + + enable_data->enable = enable; + enable_data->file = event_enable_file; + trigger_data->private_data = enable_data; + + if (glob[0] == '!') { + cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); + kfree(trigger_data); + kfree(enable_data); + ret = 0; + goto out; + } + + if (trigger) { + number = strsep(&trigger, ":"); + + ret = -EINVAL; + if (!strlen(number)) + goto out_free; + + /* + * We use the callback data field (which is a pointer) + * as our counter. + */ + ret = kstrtoul(number, 0, &trigger_data->count); + if (ret) + goto out_free; + } + + if (!param) /* if param is non-empty, it's supposed to be a filter */ + goto out_reg; + + if (!cmd_ops->set_filter) + goto out_reg; + + ret = cmd_ops->set_filter(param, trigger_data, file); + if (ret < 0) + goto out_free; + + out_reg: + /* Don't let event modules unload while probe registered */ + ret = try_module_get(event_enable_file->event_call->mod); + if (!ret) { + ret = -EBUSY; + goto out_free; + } + + ret = trace_event_enable_disable(event_enable_file, 1, 1); + if (ret < 0) + goto out_put; + ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); + /* + * The above returns on success the # of functions enabled, + * but if it didn't find any functions it returns zero. + * Consider no functions a failure too. + */ + if (!ret) { + ret = -ENOENT; + goto out_disable; + } else if (ret < 0) + goto out_disable; + /* Just return zero, not the number of enabled functions */ + ret = 0; + out: + return ret; + + out_disable: + trace_event_enable_disable(event_enable_file, 0, 1); + out_put: + module_put(event_enable_file->event_call->mod); + out_free: + if (cmd_ops->set_filter) + cmd_ops->set_filter(NULL, trigger_data, NULL); + kfree(trigger_data); + kfree(enable_data); + goto out; +} + +static int event_enable_register_trigger(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct ftrace_event_file *file) +{ + struct enable_trigger_data *enable_data = data->private_data; + struct enable_trigger_data *test_enable_data; + struct event_trigger_data *test; + int ret = 0; + + list_for_each_entry_rcu(test, &file->triggers, list) { + test_enable_data = test->private_data; + if (test_enable_data && + (test_enable_data->file == enable_data->file)) { + ret = -EEXIST; + goto out; + } + } + + if (data->ops->init) { + ret = data->ops->init(data->ops, data); + if (ret < 0) + goto out; + } + + list_add_rcu(&data->list, &file->triggers); + ret++; + + if (trace_event_trigger_enable_disable(file, 1) < 0) { + list_del_rcu(&data->list); + ret--; + } + update_cond_flag(file); +out: + return ret; +} + +static void event_enable_unregister_trigger(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *test, + struct ftrace_event_file *file) +{ + struct enable_trigger_data *test_enable_data = test->private_data; + struct enable_trigger_data *enable_data; + struct event_trigger_data *data; + bool unregistered = false; + + list_for_each_entry_rcu(data, &file->triggers, list) { + enable_data = data->private_data; + if (enable_data && + (enable_data->file == test_enable_data->file)) { + unregistered = true; + list_del_rcu(&data->list); + update_cond_flag(file); + trace_event_trigger_enable_disable(file, 0); + break; + } + } + + if (unregistered && data->ops->free) + data->ops->free(data->ops, data); +} + +static struct event_trigger_ops * +event_enable_get_trigger_ops(char *cmd, char *param) +{ + struct event_trigger_ops *ops; + bool enable; + + enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; + + if (enable) + ops = param ? &event_enable_count_trigger_ops : + &event_enable_trigger_ops; + else + ops = param ? &event_disable_count_trigger_ops : + &event_disable_trigger_ops; + + return ops; +} + +static struct event_command trigger_enable_cmd = { + .name = ENABLE_EVENT_STR, + .trigger_type = ETT_EVENT_ENABLE, + .func = event_enable_trigger_func, + .reg = event_enable_register_trigger, + .unreg = event_enable_unregister_trigger, + .get_trigger_ops = event_enable_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static struct event_command trigger_disable_cmd = { + .name = DISABLE_EVENT_STR, + .trigger_type = ETT_EVENT_ENABLE, + .func = event_enable_trigger_func, + .reg = event_enable_register_trigger, + .unreg = event_enable_unregister_trigger, + .get_trigger_ops = event_enable_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static __init void unregister_trigger_enable_disable_cmds(void) +{ + unregister_event_command(&trigger_enable_cmd); + unregister_event_command(&trigger_disable_cmd); +} + +static __init int register_trigger_enable_disable_cmds(void) +{ + int ret; + + ret = register_event_command(&trigger_enable_cmd); + if (WARN_ON(ret < 0)) + return ret; + ret = register_event_command(&trigger_disable_cmd); + if (WARN_ON(ret < 0)) + unregister_trigger_enable_disable_cmds(); + + return ret; +} + +static __init int register_trigger_traceon_traceoff_cmds(void) +{ + int ret; + + ret = register_event_command(&trigger_traceon_cmd); + if (WARN_ON(ret < 0)) + return ret; + ret = register_event_command(&trigger_traceoff_cmd); + if (WARN_ON(ret < 0)) + unregister_trigger_traceon_traceoff_cmds(); + + return ret; +} + +__init int register_trigger_cmds(void) +{ + register_trigger_traceon_traceoff_cmds(); + register_trigger_snapshot_cmd(); + register_trigger_stacktrace_cmd(); + register_trigger_enable_disable_cmds(); + + return 0; +} diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c index d06cf898dc8..d4ddde28a81 100644 --- a/kernel/trace/trace_export.c +++ b/kernel/trace/trace_export.c @@ -15,192 +15,183 @@ #include "trace_output.h" +#undef TRACE_SYSTEM +#define TRACE_SYSTEM ftrace -#undef TRACE_STRUCT -#define TRACE_STRUCT(args...) args - -extern void __bad_type_size(void); - -#undef TRACE_FIELD -#define TRACE_FIELD(type, item, assign) \ - if (sizeof(type) != sizeof(field.item)) \ - __bad_type_size(); \ - ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t" \ - "offset:%u;\tsize:%u;\n", \ - (unsigned int)offsetof(typeof(field), item), \ - (unsigned int)sizeof(field.item)); \ - if (!ret) \ - return 0; - - -#undef TRACE_FIELD_SPECIAL -#define TRACE_FIELD_SPECIAL(type_item, item, len, cmd) \ - ret = trace_seq_printf(s, "\tfield special:" #type_item ";\t" \ - "offset:%u;\tsize:%u;\n", \ - (unsigned int)offsetof(typeof(field), item), \ - (unsigned int)sizeof(field.item)); \ - if (!ret) \ - return 0; - -#undef TRACE_FIELD_ZERO_CHAR -#define TRACE_FIELD_ZERO_CHAR(item) \ - ret = trace_seq_printf(s, "\tfield:char " #item ";\t" \ - "offset:%u;\tsize:0;\n", \ - (unsigned int)offsetof(typeof(field), item)); \ - if (!ret) \ - return 0; - -#undef TRACE_FIELD_SIGN -#define TRACE_FIELD_SIGN(type, item, assign, is_signed) \ - TRACE_FIELD(type, item, assign) - -#undef TP_RAW_FMT -#define TP_RAW_FMT(args...) args - -#undef TRACE_EVENT_FORMAT -#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \ -static int \ -ftrace_format_##call(struct trace_seq *s) \ -{ \ - struct args field; \ - int ret; \ - \ - tstruct; \ - \ - trace_seq_printf(s, "\nprint fmt: \"%s\"\n", tpfmt); \ - \ - return ret; \ -} - -#undef TRACE_EVENT_FORMAT_NOFILTER -#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, \ - tpfmt) \ -static int \ -ftrace_format_##call(struct trace_seq *s) \ -{ \ - struct args field; \ - int ret; \ - \ - tstruct; \ - \ - trace_seq_printf(s, "\nprint fmt: \"%s\"\n", tpfmt); \ - \ - return ret; \ -} +/* + * The FTRACE_ENTRY_REG macro allows ftrace entry to define register + * function and thus become accesible via perf. + */ +#undef FTRACE_ENTRY_REG +#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \ + filter, regfn) \ + FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \ + filter) -#include "trace_event_types.h" +/* not needed for this file */ +#undef __field_struct +#define __field_struct(type, item) -#undef TRACE_ZERO_CHAR -#define TRACE_ZERO_CHAR(arg) +#undef __field +#define __field(type, item) type item; -#undef TRACE_FIELD -#define TRACE_FIELD(type, item, assign)\ - entry->item = assign; +#undef __field_desc +#define __field_desc(type, container, item) type item; -#undef TRACE_FIELD -#define TRACE_FIELD(type, item, assign)\ - entry->item = assign; +#undef __array +#define __array(type, item, size) type item[size]; -#undef TRACE_FIELD_SIGN -#define TRACE_FIELD_SIGN(type, item, assign, is_signed) \ - TRACE_FIELD(type, item, assign) +#undef __array_desc +#define __array_desc(type, container, item, size) type item[size]; -#undef TP_CMD -#define TP_CMD(cmd...) cmd +#undef __dynamic_array +#define __dynamic_array(type, item) type item[]; -#undef TRACE_ENTRY -#define TRACE_ENTRY entry +#undef F_STRUCT +#define F_STRUCT(args...) args -#undef TRACE_FIELD_SPECIAL -#define TRACE_FIELD_SPECIAL(type_item, item, len, cmd) \ - cmd; +#undef F_printk +#define F_printk(fmt, args...) fmt, args -#undef TRACE_EVENT_FORMAT -#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \ -int ftrace_define_fields_##call(void); \ -static int ftrace_raw_init_event_##call(void); \ - \ -struct ftrace_event_call __used \ -__attribute__((__aligned__(4))) \ -__attribute__((section("_ftrace_events"))) event_##call = { \ - .name = #call, \ - .id = proto, \ - .system = __stringify(TRACE_SYSTEM), \ - .raw_init = ftrace_raw_init_event_##call, \ - .show_format = ftrace_format_##call, \ - .define_fields = ftrace_define_fields_##call, \ +#undef FTRACE_ENTRY +#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \ +struct ____ftrace_##name { \ + tstruct \ }; \ -static int ftrace_raw_init_event_##call(void) \ +static void __always_unused ____ftrace_check_##name(void) \ { \ - INIT_LIST_HEAD(&event_##call.fields); \ - init_preds(&event_##call); \ - return 0; \ -} \ - -#undef TRACE_EVENT_FORMAT_NOFILTER -#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, \ - tpfmt) \ + struct ____ftrace_##name *__entry = NULL; \ \ -struct ftrace_event_call __used \ -__attribute__((__aligned__(4))) \ -__attribute__((section("_ftrace_events"))) event_##call = { \ - .name = #call, \ - .id = proto, \ - .system = __stringify(TRACE_SYSTEM), \ - .show_format = ftrace_format_##call, \ -}; + /* force compile-time check on F_printk() */ \ + printk(print); \ +} + +#undef FTRACE_ENTRY_DUP +#define FTRACE_ENTRY_DUP(name, struct_name, id, tstruct, print, filter) \ + FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \ + filter) -#include "trace_event_types.h" +#include "trace_entries.h" -#undef TRACE_FIELD -#define TRACE_FIELD(type, item, assign) \ +#undef __field +#define __field(type, item) \ ret = trace_define_field(event_call, #type, #item, \ offsetof(typeof(field), item), \ - sizeof(field.item), is_signed_type(type)); \ + sizeof(field.item), \ + is_signed_type(type), filter_type); \ if (ret) \ return ret; -#undef TRACE_FIELD_SPECIAL -#define TRACE_FIELD_SPECIAL(type, item, len, cmd) \ - ret = trace_define_field(event_call, #type "[" #len "]", #item, \ +#undef __field_desc +#define __field_desc(type, container, item) \ + ret = trace_define_field(event_call, #type, #item, \ + offsetof(typeof(field), \ + container.item), \ + sizeof(field.container.item), \ + is_signed_type(type), filter_type); \ + if (ret) \ + return ret; + +#undef __array +#define __array(type, item, len) \ + do { \ + char *type_str = #type"["__stringify(len)"]"; \ + BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \ + ret = trace_define_field(event_call, type_str, #item, \ offsetof(typeof(field), item), \ - sizeof(field.item), 0); \ + sizeof(field.item), \ + is_signed_type(type), filter_type); \ + if (ret) \ + return ret; \ + } while (0); + +#undef __array_desc +#define __array_desc(type, container, item, len) \ + BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \ + ret = trace_define_field(event_call, #type "[" #len "]", #item, \ + offsetof(typeof(field), \ + container.item), \ + sizeof(field.container.item), \ + is_signed_type(type), filter_type); \ if (ret) \ return ret; -#undef TRACE_FIELD_SIGN -#define TRACE_FIELD_SIGN(type, item, assign, is_signed) \ +#undef __dynamic_array +#define __dynamic_array(type, item) \ ret = trace_define_field(event_call, #type, #item, \ offsetof(typeof(field), item), \ - sizeof(field.item), is_signed); \ + 0, is_signed_type(type), filter_type);\ if (ret) \ return ret; -#undef TRACE_FIELD_ZERO_CHAR -#define TRACE_FIELD_ZERO_CHAR(item) - -#undef TRACE_EVENT_FORMAT -#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \ -int \ -ftrace_define_fields_##call(void) \ +#undef FTRACE_ENTRY +#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \ +static int __init \ +ftrace_define_fields_##name(struct ftrace_event_call *event_call) \ { \ - struct ftrace_event_call *event_call = &event_##call; \ - struct args field; \ + struct struct_name field; \ int ret; \ - \ - __common_field(unsigned char, type, 0); \ - __common_field(unsigned char, flags, 0); \ - __common_field(unsigned char, preempt_count, 0); \ - __common_field(int, pid, 1); \ - __common_field(int, tgid, 1); \ + int filter_type = filter; \ \ tstruct; \ \ return ret; \ } -#undef TRACE_EVENT_FORMAT_NOFILTER -#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, \ - tpfmt) +#include "trace_entries.h" + +#undef __entry +#define __entry REC + +#undef __field +#define __field(type, item) + +#undef __field_desc +#define __field_desc(type, container, item) + +#undef __array +#define __array(type, item, len) + +#undef __array_desc +#define __array_desc(type, container, item, len) + +#undef __dynamic_array +#define __dynamic_array(type, item) + +#undef F_printk +#define F_printk(fmt, args...) __stringify(fmt) ", " __stringify(args) + +#undef FTRACE_ENTRY_REG +#define FTRACE_ENTRY_REG(call, struct_name, etype, tstruct, print, filter,\ + regfn) \ + \ +struct ftrace_event_class __refdata event_class_ftrace_##call = { \ + .system = __stringify(TRACE_SYSTEM), \ + .define_fields = ftrace_define_fields_##call, \ + .fields = LIST_HEAD_INIT(event_class_ftrace_##call.fields),\ + .reg = regfn, \ +}; \ + \ +struct ftrace_event_call __used event_##call = { \ + .class = &event_class_ftrace_##call, \ + { \ + .name = #call, \ + }, \ + .event.type = etype, \ + .print_fmt = print, \ + .flags = TRACE_EVENT_FL_IGNORE_ENABLE | TRACE_EVENT_FL_USE_CALL_FILTER, \ +}; \ +struct ftrace_event_call __used \ +__attribute__((section("_ftrace_events"))) *__event_##call = &event_##call; + +#undef FTRACE_ENTRY +#define FTRACE_ENTRY(call, struct_name, etype, tstruct, print, filter) \ + FTRACE_ENTRY_REG(call, struct_name, etype, \ + PARAMS(tstruct), PARAMS(print), filter, NULL) + +int ftrace_event_is_function(struct ftrace_event_call *call) +{ + return call == &event_function; +} -#include "trace_event_types.h" +#include "trace_entries.h" diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c index 7402144bff2..57f0ec962d2 100644 --- a/kernel/trace/trace_functions.c +++ b/kernel/trace/trace_functions.c @@ -7,115 +7,164 @@ * Based on code from the latency_tracer, that is: * * Copyright (C) 2004-2006 Ingo Molnar - * Copyright (C) 2004 William Lee Irwin III + * Copyright (C) 2004 Nadia Yvette Chambers */ #include <linux/ring_buffer.h> #include <linux/debugfs.h> #include <linux/uaccess.h> #include <linux/ftrace.h> +#include <linux/slab.h> #include <linux/fs.h> #include "trace.h" -/* function tracing enabled */ -static int ftrace_function_enabled; +static void tracing_start_function_trace(struct trace_array *tr); +static void tracing_stop_function_trace(struct trace_array *tr); +static void +function_trace_call(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct pt_regs *pt_regs); +static void +function_stack_trace_call(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct pt_regs *pt_regs); +static struct tracer_flags func_flags; + +/* Our option */ +enum { + TRACE_FUNC_OPT_STACK = 0x1, +}; + +static int allocate_ftrace_ops(struct trace_array *tr) +{ + struct ftrace_ops *ops; + + ops = kzalloc(sizeof(*ops), GFP_KERNEL); + if (!ops) + return -ENOMEM; -static struct trace_array *func_trace; + /* Currently only the non stack verision is supported */ + ops->func = function_trace_call; + ops->flags = FTRACE_OPS_FL_RECURSION_SAFE; -static void tracing_start_function_trace(void); -static void tracing_stop_function_trace(void); + tr->ops = ops; + ops->private = tr; + return 0; +} + + +int ftrace_create_function_files(struct trace_array *tr, + struct dentry *parent) +{ + int ret; + + /* + * The top level array uses the "global_ops", and the files are + * created on boot up. + */ + if (tr->flags & TRACE_ARRAY_FL_GLOBAL) + return 0; + + ret = allocate_ftrace_ops(tr); + if (ret) + return ret; + + ftrace_create_filter_files(tr->ops, parent); + + return 0; +} + +void ftrace_destroy_function_files(struct trace_array *tr) +{ + ftrace_destroy_filter_files(tr->ops); + kfree(tr->ops); + tr->ops = NULL; +} static int function_trace_init(struct trace_array *tr) { - func_trace = tr; - tr->cpu = get_cpu(); + ftrace_func_t func; + + /* + * Instance trace_arrays get their ops allocated + * at instance creation. Unless it failed + * the allocation. + */ + if (!tr->ops) + return -ENOMEM; + + /* Currently only the global instance can do stack tracing */ + if (tr->flags & TRACE_ARRAY_FL_GLOBAL && + func_flags.val & TRACE_FUNC_OPT_STACK) + func = function_stack_trace_call; + else + func = function_trace_call; + + ftrace_init_array_ops(tr, func); + + tr->trace_buffer.cpu = get_cpu(); put_cpu(); tracing_start_cmdline_record(); - tracing_start_function_trace(); + tracing_start_function_trace(tr); return 0; } static void function_trace_reset(struct trace_array *tr) { - tracing_stop_function_trace(); + tracing_stop_function_trace(tr); tracing_stop_cmdline_record(); + ftrace_reset_array_ops(tr); } static void function_trace_start(struct trace_array *tr) { - tracing_reset_online_cpus(tr); + tracing_reset_online_cpus(&tr->trace_buffer); } static void -function_trace_call_preempt_only(unsigned long ip, unsigned long parent_ip) +function_trace_call(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct pt_regs *pt_regs) { - struct trace_array *tr = func_trace; + struct trace_array *tr = op->private; struct trace_array_cpu *data; unsigned long flags; - long disabled; - int cpu, resched; + int bit; + int cpu; int pc; - if (unlikely(!ftrace_function_enabled)) + if (unlikely(!tr->function_enabled)) return; pc = preempt_count(); - resched = ftrace_preempt_disable(); - local_save_flags(flags); - cpu = raw_smp_processor_id(); - data = tr->data[cpu]; - disabled = atomic_inc_return(&data->disabled); - - if (likely(disabled == 1)) - trace_function(tr, ip, parent_ip, flags, pc); - - atomic_dec(&data->disabled); - ftrace_preempt_enable(resched); -} - -static void -function_trace_call(unsigned long ip, unsigned long parent_ip) -{ - struct trace_array *tr = func_trace; - struct trace_array_cpu *data; - unsigned long flags; - long disabled; - int cpu; - int pc; - - if (unlikely(!ftrace_function_enabled)) - return; + preempt_disable_notrace(); - /* - * Need to use raw, since this must be called before the - * recursive protection is performed. - */ - local_irq_save(flags); - cpu = raw_smp_processor_id(); - data = tr->data[cpu]; - disabled = atomic_inc_return(&data->disabled); + bit = trace_test_and_set_recursion(TRACE_FTRACE_START, TRACE_FTRACE_MAX); + if (bit < 0) + goto out; - if (likely(disabled == 1)) { - pc = preempt_count(); + cpu = smp_processor_id(); + data = per_cpu_ptr(tr->trace_buffer.data, cpu); + if (!atomic_read(&data->disabled)) { + local_save_flags(flags); trace_function(tr, ip, parent_ip, flags, pc); } + trace_clear_recursion(bit); - atomic_dec(&data->disabled); - local_irq_restore(flags); + out: + preempt_enable_notrace(); } static void -function_stack_trace_call(unsigned long ip, unsigned long parent_ip) +function_stack_trace_call(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct pt_regs *pt_regs) { - struct trace_array *tr = func_trace; + struct trace_array *tr = op->private; struct trace_array_cpu *data; unsigned long flags; long disabled; int cpu; int pc; - if (unlikely(!ftrace_function_enabled)) + if (unlikely(!tr->function_enabled)) return; /* @@ -124,7 +173,7 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip) */ local_irq_save(flags); cpu = raw_smp_processor_id(); - data = tr->data[cpu]; + data = per_cpu_ptr(tr->trace_buffer.data, cpu); disabled = atomic_inc_return(&data->disabled); if (likely(disabled == 1)) { @@ -145,22 +194,6 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip) local_irq_restore(flags); } - -static struct ftrace_ops trace_ops __read_mostly = -{ - .func = function_trace_call, -}; - -static struct ftrace_ops trace_stack_ops __read_mostly = -{ - .func = function_stack_trace_call, -}; - -/* Our two options */ -enum { - TRACE_FUNC_OPT_STACK = 0x1, -}; - static struct tracer_opt func_opts[] = { #ifdef CONFIG_STACKTRACE { TRACER_OPT(func_stack_trace, TRACE_FUNC_OPT_STACK) }, @@ -173,131 +206,159 @@ static struct tracer_flags func_flags = { .opts = func_opts }; -static void tracing_start_function_trace(void) +static void tracing_start_function_trace(struct trace_array *tr) { - ftrace_function_enabled = 0; - - if (trace_flags & TRACE_ITER_PREEMPTONLY) - trace_ops.func = function_trace_call_preempt_only; - else - trace_ops.func = function_trace_call; - - if (func_flags.val & TRACE_FUNC_OPT_STACK) - register_ftrace_function(&trace_stack_ops); - else - register_ftrace_function(&trace_ops); - - ftrace_function_enabled = 1; + tr->function_enabled = 0; + register_ftrace_function(tr->ops); + tr->function_enabled = 1; } -static void tracing_stop_function_trace(void) +static void tracing_stop_function_trace(struct trace_array *tr) { - ftrace_function_enabled = 0; - - if (func_flags.val & TRACE_FUNC_OPT_STACK) - unregister_ftrace_function(&trace_stack_ops); - else - unregister_ftrace_function(&trace_ops); + tr->function_enabled = 0; + unregister_ftrace_function(tr->ops); } -static int func_set_flag(u32 old_flags, u32 bit, int set) +static int +func_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) { - if (bit == TRACE_FUNC_OPT_STACK) { + switch (bit) { + case TRACE_FUNC_OPT_STACK: /* do nothing if already set */ if (!!set == !!(func_flags.val & TRACE_FUNC_OPT_STACK)) - return 0; + break; + + unregister_ftrace_function(tr->ops); if (set) { - unregister_ftrace_function(&trace_ops); - register_ftrace_function(&trace_stack_ops); + tr->ops->func = function_stack_trace_call; + register_ftrace_function(tr->ops); } else { - unregister_ftrace_function(&trace_stack_ops); - register_ftrace_function(&trace_ops); + tr->ops->func = function_trace_call; + register_ftrace_function(tr->ops); } - return 0; + break; + default: + return -EINVAL; } - return -EINVAL; + return 0; } -static struct tracer function_trace __read_mostly = +static struct tracer function_trace __tracer_data = { .name = "function", .init = function_trace_init, .reset = function_trace_reset, .start = function_trace_start, - .wait_pipe = poll_wait_pipe, .flags = &func_flags, .set_flag = func_set_flag, + .allow_instances = true, #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_function, #endif }; #ifdef CONFIG_DYNAMIC_FTRACE -static void -ftrace_traceon(unsigned long ip, unsigned long parent_ip, void **data) +static int update_count(void **data) { - long *count = (long *)data; - - if (tracing_is_on()) - return; + unsigned long *count = (long *)data; if (!*count) - return; + return 0; if (*count != -1) (*count)--; - tracing_on(); + return 1; } static void -ftrace_traceoff(unsigned long ip, unsigned long parent_ip, void **data) +ftrace_traceon_count(unsigned long ip, unsigned long parent_ip, void **data) { - long *count = (long *)data; + if (tracing_is_on()) + return; + + if (update_count(data)) + tracing_on(); +} +static void +ftrace_traceoff_count(unsigned long ip, unsigned long parent_ip, void **data) +{ if (!tracing_is_on()) return; - if (!*count) + if (update_count(data)) + tracing_off(); +} + +static void +ftrace_traceon(unsigned long ip, unsigned long parent_ip, void **data) +{ + if (tracing_is_on()) return; - if (*count != -1) - (*count)--; + tracing_on(); +} + +static void +ftrace_traceoff(unsigned long ip, unsigned long parent_ip, void **data) +{ + if (!tracing_is_on()) + return; tracing_off(); } -static int -ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip, - struct ftrace_probe_ops *ops, void *data); +/* + * Skip 4: + * ftrace_stacktrace() + * function_trace_probe_call() + * ftrace_ops_list_func() + * ftrace_call() + */ +#define STACK_SKIP 4 -static struct ftrace_probe_ops traceon_probe_ops = { - .func = ftrace_traceon, - .print = ftrace_trace_onoff_print, -}; +static void +ftrace_stacktrace(unsigned long ip, unsigned long parent_ip, void **data) +{ + trace_dump_stack(STACK_SKIP); +} -static struct ftrace_probe_ops traceoff_probe_ops = { - .func = ftrace_traceoff, - .print = ftrace_trace_onoff_print, -}; +static void +ftrace_stacktrace_count(unsigned long ip, unsigned long parent_ip, void **data) +{ + if (!tracing_is_on()) + return; + + if (update_count(data)) + trace_dump_stack(STACK_SKIP); +} + +static void +ftrace_dump_probe(unsigned long ip, unsigned long parent_ip, void **data) +{ + if (update_count(data)) + ftrace_dump(DUMP_ALL); +} + +/* Only dump the current CPU buffer. */ +static void +ftrace_cpudump_probe(unsigned long ip, unsigned long parent_ip, void **data) +{ + if (update_count(data)) + ftrace_dump(DUMP_ORIG); +} static int -ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip, - struct ftrace_probe_ops *ops, void *data) +ftrace_probe_print(const char *name, struct seq_file *m, + unsigned long ip, void *data) { - char str[KSYM_SYMBOL_LEN]; long count = (long)data; - kallsyms_lookup(ip, NULL, NULL, NULL, str); - seq_printf(m, "%s:", str); - - if (ops == &traceon_probe_ops) - seq_printf(m, "traceon"); - else - seq_printf(m, "traceoff"); + seq_printf(m, "%ps:%s", (void *)ip, name); if (count == -1) seq_printf(m, ":unlimited\n"); @@ -308,25 +369,85 @@ ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip, } static int -ftrace_trace_onoff_unreg(char *glob, char *cmd, char *param) +ftrace_traceon_print(struct seq_file *m, unsigned long ip, + struct ftrace_probe_ops *ops, void *data) { - struct ftrace_probe_ops *ops; + return ftrace_probe_print("traceon", m, ip, data); +} - /* we register both traceon and traceoff to this callback */ - if (strcmp(cmd, "traceon") == 0) - ops = &traceon_probe_ops; - else - ops = &traceoff_probe_ops; +static int +ftrace_traceoff_print(struct seq_file *m, unsigned long ip, + struct ftrace_probe_ops *ops, void *data) +{ + return ftrace_probe_print("traceoff", m, ip, data); +} - unregister_ftrace_function_probe_func(glob, ops); +static int +ftrace_stacktrace_print(struct seq_file *m, unsigned long ip, + struct ftrace_probe_ops *ops, void *data) +{ + return ftrace_probe_print("stacktrace", m, ip, data); +} - return 0; +static int +ftrace_dump_print(struct seq_file *m, unsigned long ip, + struct ftrace_probe_ops *ops, void *data) +{ + return ftrace_probe_print("dump", m, ip, data); } static int -ftrace_trace_onoff_callback(char *glob, char *cmd, char *param, int enable) +ftrace_cpudump_print(struct seq_file *m, unsigned long ip, + struct ftrace_probe_ops *ops, void *data) +{ + return ftrace_probe_print("cpudump", m, ip, data); +} + +static struct ftrace_probe_ops traceon_count_probe_ops = { + .func = ftrace_traceon_count, + .print = ftrace_traceon_print, +}; + +static struct ftrace_probe_ops traceoff_count_probe_ops = { + .func = ftrace_traceoff_count, + .print = ftrace_traceoff_print, +}; + +static struct ftrace_probe_ops stacktrace_count_probe_ops = { + .func = ftrace_stacktrace_count, + .print = ftrace_stacktrace_print, +}; + +static struct ftrace_probe_ops dump_probe_ops = { + .func = ftrace_dump_probe, + .print = ftrace_dump_print, +}; + +static struct ftrace_probe_ops cpudump_probe_ops = { + .func = ftrace_cpudump_probe, + .print = ftrace_cpudump_print, +}; + +static struct ftrace_probe_ops traceon_probe_ops = { + .func = ftrace_traceon, + .print = ftrace_traceon_print, +}; + +static struct ftrace_probe_ops traceoff_probe_ops = { + .func = ftrace_traceoff, + .print = ftrace_traceoff_print, +}; + +static struct ftrace_probe_ops stacktrace_probe_ops = { + .func = ftrace_stacktrace, + .print = ftrace_stacktrace_print, +}; + +static int +ftrace_trace_probe_callback(struct ftrace_probe_ops *ops, + struct ftrace_hash *hash, char *glob, + char *cmd, char *param, int enable) { - struct ftrace_probe_ops *ops; void *count = (void *)-1; char *number; int ret; @@ -335,14 +456,10 @@ ftrace_trace_onoff_callback(char *glob, char *cmd, char *param, int enable) if (!enable) return -EINVAL; - if (glob[0] == '!') - return ftrace_trace_onoff_unreg(glob+1, cmd, param); - - /* we register both traceon and traceoff to this callback */ - if (strcmp(cmd, "traceon") == 0) - ops = &traceon_probe_ops; - else - ops = &traceoff_probe_ops; + if (glob[0] == '!') { + unregister_ftrace_function_probe_func(glob+1, ops); + return 0; + } if (!param) goto out_reg; @@ -356,14 +473,68 @@ ftrace_trace_onoff_callback(char *glob, char *cmd, char *param, int enable) * We use the callback data field (which is a pointer) * as our counter. */ - ret = strict_strtoul(number, 0, (unsigned long *)&count); + ret = kstrtoul(number, 0, (unsigned long *)&count); if (ret) return ret; out_reg: ret = register_ftrace_function_probe(glob, ops, count); - return ret; + return ret < 0 ? ret : 0; +} + +static int +ftrace_trace_onoff_callback(struct ftrace_hash *hash, + char *glob, char *cmd, char *param, int enable) +{ + struct ftrace_probe_ops *ops; + + /* we register both traceon and traceoff to this callback */ + if (strcmp(cmd, "traceon") == 0) + ops = param ? &traceon_count_probe_ops : &traceon_probe_ops; + else + ops = param ? &traceoff_count_probe_ops : &traceoff_probe_ops; + + return ftrace_trace_probe_callback(ops, hash, glob, cmd, + param, enable); +} + +static int +ftrace_stacktrace_callback(struct ftrace_hash *hash, + char *glob, char *cmd, char *param, int enable) +{ + struct ftrace_probe_ops *ops; + + ops = param ? &stacktrace_count_probe_ops : &stacktrace_probe_ops; + + return ftrace_trace_probe_callback(ops, hash, glob, cmd, + param, enable); +} + +static int +ftrace_dump_callback(struct ftrace_hash *hash, + char *glob, char *cmd, char *param, int enable) +{ + struct ftrace_probe_ops *ops; + + ops = &dump_probe_ops; + + /* Only dump once. */ + return ftrace_trace_probe_callback(ops, hash, glob, cmd, + "1", enable); +} + +static int +ftrace_cpudump_callback(struct ftrace_hash *hash, + char *glob, char *cmd, char *param, int enable) +{ + struct ftrace_probe_ops *ops; + + ops = &cpudump_probe_ops; + + /* Only dump once. */ + return ftrace_trace_probe_callback(ops, hash, glob, cmd, + "1", enable); } static struct ftrace_func_command ftrace_traceon_cmd = { @@ -376,6 +547,21 @@ static struct ftrace_func_command ftrace_traceoff_cmd = { .func = ftrace_trace_onoff_callback, }; +static struct ftrace_func_command ftrace_stacktrace_cmd = { + .name = "stacktrace", + .func = ftrace_stacktrace_callback, +}; + +static struct ftrace_func_command ftrace_dump_cmd = { + .name = "dump", + .func = ftrace_dump_callback, +}; + +static struct ftrace_func_command ftrace_cpudump_cmd = { + .name = "cpudump", + .func = ftrace_cpudump_callback, +}; + static int __init init_func_cmd_traceon(void) { int ret; @@ -386,7 +572,31 @@ static int __init init_func_cmd_traceon(void) ret = register_ftrace_command(&ftrace_traceon_cmd); if (ret) - unregister_ftrace_command(&ftrace_traceoff_cmd); + goto out_free_traceoff; + + ret = register_ftrace_command(&ftrace_stacktrace_cmd); + if (ret) + goto out_free_traceon; + + ret = register_ftrace_command(&ftrace_dump_cmd); + if (ret) + goto out_free_stacktrace; + + ret = register_ftrace_command(&ftrace_cpudump_cmd); + if (ret) + goto out_free_dump; + + return 0; + + out_free_dump: + unregister_ftrace_command(&ftrace_dump_cmd); + out_free_stacktrace: + unregister_ftrace_command(&ftrace_stacktrace_cmd); + out_free_traceon: + unregister_ftrace_command(&ftrace_traceon_cmd); + out_free_traceoff: + unregister_ftrace_command(&ftrace_traceoff_cmd); + return ret; } #else @@ -401,5 +611,4 @@ static __init int init_function_trace(void) init_func_cmd_traceon(); return register_tracer(&function_trace); } -device_initcall(init_function_trace); - +core_initcall(init_function_trace); diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index d2249abafb5..4de3e57f723 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -9,25 +9,36 @@ #include <linux/debugfs.h> #include <linux/uaccess.h> #include <linux/ftrace.h> +#include <linux/slab.h> #include <linux/fs.h> #include "trace.h" #include "trace_output.h" -struct fgraph_data { +/* When set, irq functions will be ignored */ +static int ftrace_graph_skip_irqs; + +struct fgraph_cpu_data { pid_t last_pid; int depth; + int depth_irq; + int ignore; + unsigned long enter_funcs[FTRACE_RETFUNC_DEPTH]; +}; + +struct fgraph_data { + struct fgraph_cpu_data __percpu *cpu_data; + + /* Place to preserve last processed entry. */ + struct ftrace_graph_ent_entry ent; + struct ftrace_graph_ret_entry ret; + int failed; + int cpu; }; #define TRACE_GRAPH_INDENT 2 -/* Flag options */ -#define TRACE_GRAPH_PRINT_OVERRUN 0x1 -#define TRACE_GRAPH_PRINT_CPU 0x2 -#define TRACE_GRAPH_PRINT_OVERHEAD 0x4 -#define TRACE_GRAPH_PRINT_PROC 0x8 -#define TRACE_GRAPH_PRINT_DURATION 0x10 -#define TRACE_GRAPH_PRINT_ABS_TIME 0X20 +static unsigned int max_depth; static struct tracer_opt trace_opts[] = { /* Display overruns? (for self-debug purpose) */ @@ -42,18 +53,36 @@ static struct tracer_opt trace_opts[] = { { TRACER_OPT(funcgraph-duration, TRACE_GRAPH_PRINT_DURATION) }, /* Display absolute time of an entry */ { TRACER_OPT(funcgraph-abstime, TRACE_GRAPH_PRINT_ABS_TIME) }, + /* Display interrupts */ + { TRACER_OPT(funcgraph-irqs, TRACE_GRAPH_PRINT_IRQS) }, + /* Display function name after trailing } */ + { TRACER_OPT(funcgraph-tail, TRACE_GRAPH_PRINT_TAIL) }, { } /* Empty entry */ }; static struct tracer_flags tracer_flags = { - /* Don't display overruns and proc by default */ + /* Don't display overruns, proc, or tail by default */ .val = TRACE_GRAPH_PRINT_CPU | TRACE_GRAPH_PRINT_OVERHEAD | - TRACE_GRAPH_PRINT_DURATION, + TRACE_GRAPH_PRINT_DURATION | TRACE_GRAPH_PRINT_IRQS, .opts = trace_opts }; -/* pid on the last trace processed */ +static struct trace_array *graph_array; +/* + * DURATION column is being also used to display IRQ signs, + * following values are used by print_graph_irq and others + * to fill in space into DURATION column. + */ +enum { + FLAGS_FILL_FULL = 1 << TRACE_GRAPH_PRINT_FILL_SHIFT, + FLAGS_FILL_START = 2 << TRACE_GRAPH_PRINT_FILL_SHIFT, + FLAGS_FILL_END = 3 << TRACE_GRAPH_PRINT_FILL_SHIFT, +}; + +static enum print_line_t +print_graph_duration(unsigned long long duration, struct trace_seq *s, + u32 flags); /* Add a function return address to the trace stack on thread info.*/ int @@ -78,16 +107,37 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth, return -EBUSY; } + /* + * The curr_ret_stack is an index to ftrace return stack of + * current task. Its value should be in [0, FTRACE_RETFUNC_ + * DEPTH) when the function graph tracer is used. To support + * filtering out specific functions, it makes the index + * negative by subtracting huge value (FTRACE_NOTRACE_DEPTH) + * so when it sees a negative index the ftrace will ignore + * the record. And the index gets recovered when returning + * from the filtered function by adding the FTRACE_NOTRACE_ + * DEPTH and then it'll continue to record functions normally. + * + * The curr_ret_stack is initialized to -1 and get increased + * in this function. So it can be less than -1 only if it was + * filtered out via ftrace_graph_notrace_addr() which can be + * set from set_graph_notrace file in debugfs by user. + */ + if (current->curr_ret_stack < -1) + return -EBUSY; + calltime = trace_clock_local(); index = ++current->curr_ret_stack; + if (ftrace_graph_notrace_addr(func)) + current->curr_ret_stack -= FTRACE_NOTRACE_DEPTH; barrier(); current->ret_stack[index].ret = ret; current->ret_stack[index].func = func; current->ret_stack[index].calltime = calltime; current->ret_stack[index].subtime = 0; current->ret_stack[index].fp = frame_pointer; - *depth = index; + *depth = current->curr_ret_stack; return 0; } @@ -101,7 +151,17 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret, index = current->curr_ret_stack; - if (unlikely(index < 0)) { + /* + * A negative index here means that it's just returned from a + * notrace'd function. Recover index to get an original + * return address. See ftrace_push_return_trace(). + * + * TODO: Need to check whether the stack gets corrupted. + */ + if (index < 0) + index += FTRACE_NOTRACE_DEPTH; + + if (unlikely(index < 0 || index >= FTRACE_RETFUNC_DEPTH)) { ftrace_graph_stop(); WARN_ON(1); /* Might as well panic, otherwise we have no where to go */ @@ -109,7 +169,7 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret, return; } -#ifdef CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST +#if defined(CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST) && !defined(CC_USING_FENTRY) /* * The arch may choose to record the frame pointer used * and check it here to make sure that it is what we expect it @@ -120,11 +180,14 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret, * * Currently, x86_32 with optimize for size (-Os) makes the latest * gcc do the above. + * + * Note, -mfentry does not use frame pointers, and this test + * is not needed if CC_USING_FENTRY is set. */ if (unlikely(current->ret_stack[index].fp != frame_pointer)) { ftrace_graph_stop(); WARN(1, "Bad frame pointer: expected %lx, received %lx\n" - " from func %pF return to %lx\n", + " from func %ps return to %lx\n", current->ret_stack[index].fp, frame_pointer, (void *)current->ret_stack[index].func, @@ -152,9 +215,24 @@ unsigned long ftrace_return_to_handler(unsigned long frame_pointer) ftrace_pop_return_trace(&trace, &ret, frame_pointer); trace.rettime = trace_clock_local(); - ftrace_graph_return(&trace); barrier(); current->curr_ret_stack--; + /* + * The curr_ret_stack can be less than -1 only if it was + * filtered out and it's about to return from the function. + * Recover the index and continue to trace normal functions. + */ + if (current->curr_ret_stack < -1) { + current->curr_ret_stack += FTRACE_NOTRACE_DEPTH; + return ret; + } + + /* + * The trace should run after decrementing the ret counter + * in case an interrupt were to come in. We don't want to + * lose the interrupt if max_depth is set. + */ + ftrace_graph_return(&trace); if (unlikely(!ret)) { ftrace_graph_stop(); @@ -166,10 +244,194 @@ unsigned long ftrace_return_to_handler(unsigned long frame_pointer) return ret; } +int __trace_graph_entry(struct trace_array *tr, + struct ftrace_graph_ent *trace, + unsigned long flags, + int pc) +{ + struct ftrace_event_call *call = &event_funcgraph_entry; + struct ring_buffer_event *event; + struct ring_buffer *buffer = tr->trace_buffer.buffer; + struct ftrace_graph_ent_entry *entry; + + if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) + return 0; + + event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_ENT, + sizeof(*entry), flags, pc); + if (!event) + return 0; + entry = ring_buffer_event_data(event); + entry->graph_ent = *trace; + if (!call_filter_check_discard(call, entry, buffer, event)) + __buffer_unlock_commit(buffer, event); + + return 1; +} + +static inline int ftrace_graph_ignore_irqs(void) +{ + if (!ftrace_graph_skip_irqs || trace_recursion_test(TRACE_IRQ_BIT)) + return 0; + + return in_irq(); +} + +int trace_graph_entry(struct ftrace_graph_ent *trace) +{ + struct trace_array *tr = graph_array; + struct trace_array_cpu *data; + unsigned long flags; + long disabled; + int ret; + int cpu; + int pc; + + if (!ftrace_trace_task(current)) + return 0; + + /* trace it when it is-nested-in or is a function enabled. */ + if ((!(trace->depth || ftrace_graph_addr(trace->func)) || + ftrace_graph_ignore_irqs()) || (trace->depth < 0) || + (max_depth && trace->depth >= max_depth)) + return 0; + + /* + * Do not trace a function if it's filtered by set_graph_notrace. + * Make the index of ret stack negative to indicate that it should + * ignore further functions. But it needs its own ret stack entry + * to recover the original index in order to continue tracing after + * returning from the function. + */ + if (ftrace_graph_notrace_addr(trace->func)) + return 1; + + local_irq_save(flags); + cpu = raw_smp_processor_id(); + data = per_cpu_ptr(tr->trace_buffer.data, cpu); + disabled = atomic_inc_return(&data->disabled); + if (likely(disabled == 1)) { + pc = preempt_count(); + ret = __trace_graph_entry(tr, trace, flags, pc); + } else { + ret = 0; + } + + atomic_dec(&data->disabled); + local_irq_restore(flags); + + return ret; +} + +int trace_graph_thresh_entry(struct ftrace_graph_ent *trace) +{ + if (tracing_thresh) + return 1; + else + return trace_graph_entry(trace); +} + +static void +__trace_graph_function(struct trace_array *tr, + unsigned long ip, unsigned long flags, int pc) +{ + u64 time = trace_clock_local(); + struct ftrace_graph_ent ent = { + .func = ip, + .depth = 0, + }; + struct ftrace_graph_ret ret = { + .func = ip, + .depth = 0, + .calltime = time, + .rettime = time, + }; + + __trace_graph_entry(tr, &ent, flags, pc); + __trace_graph_return(tr, &ret, flags, pc); +} + +void +trace_graph_function(struct trace_array *tr, + unsigned long ip, unsigned long parent_ip, + unsigned long flags, int pc) +{ + __trace_graph_function(tr, ip, flags, pc); +} + +void __trace_graph_return(struct trace_array *tr, + struct ftrace_graph_ret *trace, + unsigned long flags, + int pc) +{ + struct ftrace_event_call *call = &event_funcgraph_exit; + struct ring_buffer_event *event; + struct ring_buffer *buffer = tr->trace_buffer.buffer; + struct ftrace_graph_ret_entry *entry; + + if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) + return; + + event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_RET, + sizeof(*entry), flags, pc); + if (!event) + return; + entry = ring_buffer_event_data(event); + entry->ret = *trace; + if (!call_filter_check_discard(call, entry, buffer, event)) + __buffer_unlock_commit(buffer, event); +} + +void trace_graph_return(struct ftrace_graph_ret *trace) +{ + struct trace_array *tr = graph_array; + struct trace_array_cpu *data; + unsigned long flags; + long disabled; + int cpu; + int pc; + + local_irq_save(flags); + cpu = raw_smp_processor_id(); + data = per_cpu_ptr(tr->trace_buffer.data, cpu); + disabled = atomic_inc_return(&data->disabled); + if (likely(disabled == 1)) { + pc = preempt_count(); + __trace_graph_return(tr, trace, flags, pc); + } + atomic_dec(&data->disabled); + local_irq_restore(flags); +} + +void set_graph_array(struct trace_array *tr) +{ + graph_array = tr; + + /* Make graph_array visible before we start tracing */ + + smp_mb(); +} + +void trace_graph_thresh_return(struct ftrace_graph_ret *trace) +{ + if (tracing_thresh && + (trace->rettime - trace->calltime < tracing_thresh)) + return; + else + trace_graph_return(trace); +} + static int graph_trace_init(struct trace_array *tr) { - int ret = register_ftrace_graph(&trace_graph_return, - &trace_graph_entry); + int ret; + + set_graph_array(tr); + if (tracing_thresh) + ret = register_ftrace_graph(&trace_graph_thresh_return, + &trace_graph_thresh_entry); + else + ret = register_ftrace_graph(&trace_graph_return, + &trace_graph_entry); if (ret) return ret; tracing_start_cmdline_record(); @@ -183,43 +445,19 @@ static void graph_trace_reset(struct trace_array *tr) unregister_ftrace_graph(); } -static inline int log10_cpu(int nb) -{ - if (nb / 100) - return 3; - if (nb / 10) - return 2; - return 1; -} +static int max_bytes_for_cpu; static enum print_line_t print_graph_cpu(struct trace_seq *s, int cpu) { - int i; int ret; - int log10_this = log10_cpu(cpu); - int log10_all = log10_cpu(cpumask_weight(cpu_online_mask)); - /* * Start with a space character - to make it stand out * to the right a bit when trace output is pasted into * email: */ - ret = trace_seq_printf(s, " "); - - /* - * Tricky - we space the CPU field according to the max - * number of online CPUs. On a 2-cpu system it would take - * a maximum of 1 digit - on a 128 cpu system it would - * take up to 3 digits: - */ - for (i = 0; i < log10_all - log10_this; i++) { - ret = trace_seq_printf(s, " "); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - } - ret = trace_seq_printf(s, "%d) ", cpu); + ret = trace_seq_printf(s, " %*d) ", max_bytes_for_cpu, cpu); if (!ret) return TRACE_TYPE_PARTIAL_LINE; @@ -251,7 +489,7 @@ print_graph_proc(struct trace_seq *s, pid_t pid) /* First spaces to align center */ for (i = 0; i < spaces / 2; i++) { - ret = trace_seq_printf(s, " "); + ret = trace_seq_putc(s, ' '); if (!ret) return TRACE_TYPE_PARTIAL_LINE; } @@ -262,7 +500,7 @@ print_graph_proc(struct trace_seq *s, pid_t pid) /* Last spaces to align center */ for (i = 0; i < spaces - (spaces / 2); i++) { - ret = trace_seq_printf(s, " "); + ret = trace_seq_putc(s, ' '); if (!ret) return TRACE_TYPE_PARTIAL_LINE; } @@ -270,6 +508,15 @@ print_graph_proc(struct trace_seq *s, pid_t pid) } +static enum print_line_t +print_graph_lat_fmt(struct trace_seq *s, struct trace_entry *entry) +{ + if (!trace_seq_putc(s, ' ')) + return 0; + + return trace_print_lat_fmt(s, entry); +} + /* If the pid changed since the last trace, output this event */ static enum print_line_t verif_pid(struct trace_seq *s, pid_t pid, int cpu, struct fgraph_data *data) @@ -281,7 +528,7 @@ verif_pid(struct trace_seq *s, pid_t pid, int cpu, struct fgraph_data *data) if (!data) return TRACE_TYPE_HANDLED; - last_pid = &(per_cpu_ptr(data, cpu)->last_pid); + last_pid = &(per_cpu_ptr(data->cpu_data, cpu)->last_pid); if (*last_pid == pid) return TRACE_TYPE_HANDLED; @@ -299,7 +546,7 @@ verif_pid(struct trace_seq *s, pid_t pid, int cpu, struct fgraph_data *data) ------------------------------------------ */ - ret = trace_seq_printf(s, + ret = trace_seq_puts(s, " ------------------------------------------\n"); if (!ret) return TRACE_TYPE_PARTIAL_LINE; @@ -312,7 +559,7 @@ verif_pid(struct trace_seq *s, pid_t pid, int cpu, struct fgraph_data *data) if (ret == TRACE_TYPE_PARTIAL_LINE) return TRACE_TYPE_PARTIAL_LINE; - ret = trace_seq_printf(s, " => "); + ret = trace_seq_puts(s, " => "); if (!ret) return TRACE_TYPE_PARTIAL_LINE; @@ -320,7 +567,7 @@ verif_pid(struct trace_seq *s, pid_t pid, int cpu, struct fgraph_data *data) if (ret == TRACE_TYPE_PARTIAL_LINE) return TRACE_TYPE_PARTIAL_LINE; - ret = trace_seq_printf(s, + ret = trace_seq_puts(s, "\n ------------------------------------------\n\n"); if (!ret) return TRACE_TYPE_PARTIAL_LINE; @@ -332,27 +579,59 @@ static struct ftrace_graph_ret_entry * get_return_for_leaf(struct trace_iterator *iter, struct ftrace_graph_ent_entry *curr) { - struct ring_buffer_iter *ring_iter; + struct fgraph_data *data = iter->private; + struct ring_buffer_iter *ring_iter = NULL; struct ring_buffer_event *event; struct ftrace_graph_ret_entry *next; - ring_iter = iter->buffer_iter[iter->cpu]; + /* + * If the previous output failed to write to the seq buffer, + * then we just reuse the data from before. + */ + if (data && data->failed) { + curr = &data->ent; + next = &data->ret; + } else { + + ring_iter = trace_buffer_iter(iter, iter->cpu); + + /* First peek to compare current entry and the next one */ + if (ring_iter) + event = ring_buffer_iter_peek(ring_iter, NULL); + else { + /* + * We need to consume the current entry to see + * the next one. + */ + ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, + NULL, NULL); + event = ring_buffer_peek(iter->trace_buffer->buffer, iter->cpu, + NULL, NULL); + } - /* First peek to compare current entry and the next one */ - if (ring_iter) - event = ring_buffer_iter_peek(ring_iter, NULL); - else { - /* We need to consume the current entry to see the next one */ - ring_buffer_consume(iter->tr->buffer, iter->cpu, NULL); - event = ring_buffer_peek(iter->tr->buffer, iter->cpu, - NULL); + if (!event) + return NULL; + + next = ring_buffer_event_data(event); + + if (data) { + /* + * Save current and next entries for later reference + * if the output fails. + */ + data->ent = *curr; + /* + * If the next event is not a return type, then + * we only care about what type it is. Otherwise we can + * safely copy the entire event. + */ + if (next->ent.type == TRACE_GRAPH_RET) + data->ret = *next; + else + data->ret.ent.type = next->ent.type; + } } - if (!event) - return NULL; - - next = ring_buffer_event_data(event); - if (next->ent.type != TRACE_GRAPH_RET) return NULL; @@ -367,31 +646,6 @@ get_return_for_leaf(struct trace_iterator *iter, return next; } -/* Signal a overhead of time execution to the output */ -static int -print_graph_overhead(unsigned long long duration, struct trace_seq *s) -{ - /* If duration disappear, we don't need anything */ - if (!(tracer_flags.val & TRACE_GRAPH_PRINT_DURATION)) - return 1; - - /* Non nested entry or return */ - if (duration == -1) - return trace_seq_printf(s, " "); - - if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) { - /* Duration exceeded 100 msecs */ - if (duration > 100000ULL) - return trace_seq_printf(s, "! "); - - /* Duration exceeded 10 msecs */ - if (duration > 10000ULL) - return trace_seq_printf(s, "+ "); - } - - return trace_seq_printf(s, " "); -} - static int print_graph_abs_time(u64 t, struct trace_seq *s) { unsigned long usecs_rem; @@ -405,7 +659,7 @@ static int print_graph_abs_time(u64 t, struct trace_seq *s) static enum print_line_t print_graph_irq(struct trace_iterator *iter, unsigned long addr, - enum trace_type type, int cpu, pid_t pid) + enum trace_type type, int cpu, pid_t pid, u32 flags) { int ret; struct trace_seq *s = &iter->seq; @@ -414,46 +668,50 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr, addr >= (unsigned long)__irqentry_text_end) return TRACE_TYPE_UNHANDLED; - /* Absolute time */ - if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME) { - ret = print_graph_abs_time(iter->ts, s); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - } + if (trace_flags & TRACE_ITER_CONTEXT_INFO) { + /* Absolute time */ + if (flags & TRACE_GRAPH_PRINT_ABS_TIME) { + ret = print_graph_abs_time(iter->ts, s); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + } - /* Cpu */ - if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) { - ret = print_graph_cpu(s, cpu); - if (ret == TRACE_TYPE_PARTIAL_LINE) - return TRACE_TYPE_PARTIAL_LINE; - } - /* Proc */ - if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) { - ret = print_graph_proc(s, pid); - if (ret == TRACE_TYPE_PARTIAL_LINE) - return TRACE_TYPE_PARTIAL_LINE; - ret = trace_seq_printf(s, " | "); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; + /* Cpu */ + if (flags & TRACE_GRAPH_PRINT_CPU) { + ret = print_graph_cpu(s, cpu); + if (ret == TRACE_TYPE_PARTIAL_LINE) + return TRACE_TYPE_PARTIAL_LINE; + } + + /* Proc */ + if (flags & TRACE_GRAPH_PRINT_PROC) { + ret = print_graph_proc(s, pid); + if (ret == TRACE_TYPE_PARTIAL_LINE) + return TRACE_TYPE_PARTIAL_LINE; + ret = trace_seq_puts(s, " | "); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + } } /* No overhead */ - ret = print_graph_overhead(-1, s); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; + ret = print_graph_duration(0, s, flags | FLAGS_FILL_START); + if (ret != TRACE_TYPE_HANDLED) + return ret; if (type == TRACE_GRAPH_ENT) - ret = trace_seq_printf(s, "==========>"); + ret = trace_seq_puts(s, "==========>"); else - ret = trace_seq_printf(s, "<=========="); + ret = trace_seq_puts(s, "<=========="); if (!ret) return TRACE_TYPE_PARTIAL_LINE; - /* Don't close the duration column if haven't one */ - if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) - trace_seq_printf(s, " |"); - ret = trace_seq_printf(s, "\n"); + ret = print_graph_duration(0, s, flags | FLAGS_FILL_END); + if (ret != TRACE_TYPE_HANDLED) + return ret; + + ret = trace_seq_putc(s, '\n'); if (!ret) return TRACE_TYPE_PARTIAL_LINE; @@ -481,20 +739,22 @@ trace_print_graph_duration(unsigned long long duration, struct trace_seq *s) /* Print nsecs (we don't want to exceed 7 numbers) */ if (len < 7) { - snprintf(nsecs_str, 8 - len, "%03lu", nsecs_rem); + size_t slen = min_t(size_t, sizeof(nsecs_str), 8UL - len); + + snprintf(nsecs_str, slen, "%03lu", nsecs_rem); ret = trace_seq_printf(s, ".%s", nsecs_str); if (!ret) return TRACE_TYPE_PARTIAL_LINE; len += strlen(nsecs_str); } - ret = trace_seq_printf(s, " us "); + ret = trace_seq_puts(s, " us "); if (!ret) return TRACE_TYPE_PARTIAL_LINE; /* Print remaining spaces to fit the row's width */ for (i = len; i < 7; i++) { - ret = trace_seq_printf(s, " "); + ret = trace_seq_putc(s, ' '); if (!ret) return TRACE_TYPE_PARTIAL_LINE; } @@ -502,15 +762,55 @@ trace_print_graph_duration(unsigned long long duration, struct trace_seq *s) } static enum print_line_t -print_graph_duration(unsigned long long duration, struct trace_seq *s) +print_graph_duration(unsigned long long duration, struct trace_seq *s, + u32 flags) { - int ret; + int ret = -1; + + if (!(flags & TRACE_GRAPH_PRINT_DURATION) || + !(trace_flags & TRACE_ITER_CONTEXT_INFO)) + return TRACE_TYPE_HANDLED; + + /* No real adata, just filling the column with spaces */ + switch (flags & TRACE_GRAPH_PRINT_FILL_MASK) { + case FLAGS_FILL_FULL: + ret = trace_seq_puts(s, " | "); + return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; + case FLAGS_FILL_START: + ret = trace_seq_puts(s, " "); + return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; + case FLAGS_FILL_END: + ret = trace_seq_puts(s, " |"); + return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; + } + + /* Signal a overhead of time execution to the output */ + if (flags & TRACE_GRAPH_PRINT_OVERHEAD) { + /* Duration exceeded 100 msecs */ + if (duration > 100000ULL) + ret = trace_seq_puts(s, "! "); + /* Duration exceeded 10 msecs */ + else if (duration > 10000ULL) + ret = trace_seq_puts(s, "+ "); + } + + /* + * The -1 means we either did not exceed the duration tresholds + * or we dont want to print out the overhead. Either way we need + * to fill out the space. + */ + if (ret == -1) + ret = trace_seq_puts(s, " "); + + /* Catching here any failure happenned above */ + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; ret = trace_print_graph_duration(duration, s); if (ret != TRACE_TYPE_HANDLED) return ret; - ret = trace_seq_printf(s, "| "); + ret = trace_seq_puts(s, "| "); if (!ret) return TRACE_TYPE_PARTIAL_LINE; @@ -521,7 +821,8 @@ print_graph_duration(unsigned long long duration, struct trace_seq *s) static enum print_line_t print_graph_entry_leaf(struct trace_iterator *iter, struct ftrace_graph_ent_entry *entry, - struct ftrace_graph_ret_entry *ret_entry, struct trace_seq *s) + struct ftrace_graph_ret_entry *ret_entry, + struct trace_seq *s, u32 flags) { struct fgraph_data *data = iter->private; struct ftrace_graph_ret *graph_ret; @@ -535,41 +836,36 @@ print_graph_entry_leaf(struct trace_iterator *iter, duration = graph_ret->rettime - graph_ret->calltime; if (data) { + struct fgraph_cpu_data *cpu_data; int cpu = iter->cpu; - int *depth = &(per_cpu_ptr(data, cpu)->depth); + + cpu_data = per_cpu_ptr(data->cpu_data, cpu); /* * Comments display at + 1 to depth. Since * this is a leaf function, keep the comments * equal to this depth. */ - *depth = call->depth - 1; + cpu_data->depth = call->depth - 1; + + /* No need to keep this function around for this depth */ + if (call->depth < FTRACE_RETFUNC_DEPTH) + cpu_data->enter_funcs[call->depth] = 0; } - /* Overhead */ - ret = print_graph_overhead(duration, s); - if (!ret) + /* Overhead and duration */ + ret = print_graph_duration(duration, s, flags); + if (ret == TRACE_TYPE_PARTIAL_LINE) return TRACE_TYPE_PARTIAL_LINE; - /* Duration */ - if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) { - ret = print_graph_duration(duration, s); - if (ret == TRACE_TYPE_PARTIAL_LINE) - return TRACE_TYPE_PARTIAL_LINE; - } - /* Function */ for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) { - ret = trace_seq_printf(s, " "); + ret = trace_seq_putc(s, ' '); if (!ret) return TRACE_TYPE_PARTIAL_LINE; } - ret = seq_print_ip_sym(s, call->func, 0); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - ret = trace_seq_printf(s, "();\n"); + ret = trace_seq_printf(s, "%ps();\n", (void *)call->func); if (!ret) return TRACE_TYPE_PARTIAL_LINE; @@ -579,7 +875,7 @@ print_graph_entry_leaf(struct trace_iterator *iter, static enum print_line_t print_graph_entry_nested(struct trace_iterator *iter, struct ftrace_graph_ent_entry *entry, - struct trace_seq *s, int cpu) + struct trace_seq *s, int cpu, u32 flags) { struct ftrace_graph_ent *call = &entry->graph_ent; struct fgraph_data *data = iter->private; @@ -587,36 +883,30 @@ print_graph_entry_nested(struct trace_iterator *iter, int i; if (data) { + struct fgraph_cpu_data *cpu_data; int cpu = iter->cpu; - int *depth = &(per_cpu_ptr(data, cpu)->depth); - *depth = call->depth; - } + cpu_data = per_cpu_ptr(data->cpu_data, cpu); + cpu_data->depth = call->depth; - /* No overhead */ - ret = print_graph_overhead(-1, s); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; + /* Save this function pointer to see if the exit matches */ + if (call->depth < FTRACE_RETFUNC_DEPTH) + cpu_data->enter_funcs[call->depth] = call->func; + } /* No time */ - if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) { - ret = trace_seq_printf(s, " | "); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - } + ret = print_graph_duration(0, s, flags | FLAGS_FILL_FULL); + if (ret != TRACE_TYPE_HANDLED) + return ret; /* Function */ for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) { - ret = trace_seq_printf(s, " "); + ret = trace_seq_putc(s, ' '); if (!ret) return TRACE_TYPE_PARTIAL_LINE; } - ret = seq_print_ip_sym(s, call->func, 0); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - ret = trace_seq_printf(s, "() {\n"); + ret = trace_seq_printf(s, "%ps() {\n", (void *)call->func); if (!ret) return TRACE_TYPE_PARTIAL_LINE; @@ -629,7 +919,7 @@ print_graph_entry_nested(struct trace_iterator *iter, static enum print_line_t print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s, - int type, unsigned long addr) + int type, unsigned long addr, u32 flags) { struct fgraph_data *data = iter->private; struct trace_entry *ent = iter->ent; @@ -642,116 +932,266 @@ print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s, if (type) { /* Interrupt */ - ret = print_graph_irq(iter, addr, type, cpu, ent->pid); + ret = print_graph_irq(iter, addr, type, cpu, ent->pid, flags); if (ret == TRACE_TYPE_PARTIAL_LINE) return TRACE_TYPE_PARTIAL_LINE; } + if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) + return 0; + /* Absolute time */ - if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME) { + if (flags & TRACE_GRAPH_PRINT_ABS_TIME) { ret = print_graph_abs_time(iter->ts, s); if (!ret) return TRACE_TYPE_PARTIAL_LINE; } /* Cpu */ - if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) { + if (flags & TRACE_GRAPH_PRINT_CPU) { ret = print_graph_cpu(s, cpu); if (ret == TRACE_TYPE_PARTIAL_LINE) return TRACE_TYPE_PARTIAL_LINE; } /* Proc */ - if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) { + if (flags & TRACE_GRAPH_PRINT_PROC) { ret = print_graph_proc(s, ent->pid); if (ret == TRACE_TYPE_PARTIAL_LINE) return TRACE_TYPE_PARTIAL_LINE; - ret = trace_seq_printf(s, " | "); + ret = trace_seq_puts(s, " | "); if (!ret) return TRACE_TYPE_PARTIAL_LINE; } + /* Latency format */ + if (trace_flags & TRACE_ITER_LATENCY_FMT) { + ret = print_graph_lat_fmt(s, ent); + if (ret == TRACE_TYPE_PARTIAL_LINE) + return TRACE_TYPE_PARTIAL_LINE; + } + return 0; } +/* + * Entry check for irq code + * + * returns 1 if + * - we are inside irq code + * - we just entered irq code + * + * retunns 0 if + * - funcgraph-interrupts option is set + * - we are not inside irq code + */ +static int +check_irq_entry(struct trace_iterator *iter, u32 flags, + unsigned long addr, int depth) +{ + int cpu = iter->cpu; + int *depth_irq; + struct fgraph_data *data = iter->private; + + /* + * If we are either displaying irqs, or we got called as + * a graph event and private data does not exist, + * then we bypass the irq check. + */ + if ((flags & TRACE_GRAPH_PRINT_IRQS) || + (!data)) + return 0; + + depth_irq = &(per_cpu_ptr(data->cpu_data, cpu)->depth_irq); + + /* + * We are inside the irq code + */ + if (*depth_irq >= 0) + return 1; + + if ((addr < (unsigned long)__irqentry_text_start) || + (addr >= (unsigned long)__irqentry_text_end)) + return 0; + + /* + * We are entering irq code. + */ + *depth_irq = depth; + return 1; +} + +/* + * Return check for irq code + * + * returns 1 if + * - we are inside irq code + * - we just left irq code + * + * returns 0 if + * - funcgraph-interrupts option is set + * - we are not inside irq code + */ +static int +check_irq_return(struct trace_iterator *iter, u32 flags, int depth) +{ + int cpu = iter->cpu; + int *depth_irq; + struct fgraph_data *data = iter->private; + + /* + * If we are either displaying irqs, or we got called as + * a graph event and private data does not exist, + * then we bypass the irq check. + */ + if ((flags & TRACE_GRAPH_PRINT_IRQS) || + (!data)) + return 0; + + depth_irq = &(per_cpu_ptr(data->cpu_data, cpu)->depth_irq); + + /* + * We are not inside the irq code. + */ + if (*depth_irq == -1) + return 0; + + /* + * We are inside the irq code, and this is returning entry. + * Let's not trace it and clear the entry depth, since + * we are out of irq code. + * + * This condition ensures that we 'leave the irq code' once + * we are out of the entry depth. Thus protecting us from + * the RETURN entry loss. + */ + if (*depth_irq >= depth) { + *depth_irq = -1; + return 1; + } + + /* + * We are inside the irq code, and this is not the entry. + */ + return 1; +} + static enum print_line_t print_graph_entry(struct ftrace_graph_ent_entry *field, struct trace_seq *s, - struct trace_iterator *iter) + struct trace_iterator *iter, u32 flags) { - int cpu = iter->cpu; + struct fgraph_data *data = iter->private; struct ftrace_graph_ent *call = &field->graph_ent; struct ftrace_graph_ret_entry *leaf_ret; + static enum print_line_t ret; + int cpu = iter->cpu; - if (print_graph_prologue(iter, s, TRACE_GRAPH_ENT, call->func)) + if (check_irq_entry(iter, flags, call->func, call->depth)) + return TRACE_TYPE_HANDLED; + + if (print_graph_prologue(iter, s, TRACE_GRAPH_ENT, call->func, flags)) return TRACE_TYPE_PARTIAL_LINE; leaf_ret = get_return_for_leaf(iter, field); if (leaf_ret) - return print_graph_entry_leaf(iter, field, leaf_ret, s); + ret = print_graph_entry_leaf(iter, field, leaf_ret, s, flags); else - return print_graph_entry_nested(iter, field, s, cpu); + ret = print_graph_entry_nested(iter, field, s, cpu, flags); + + if (data) { + /* + * If we failed to write our output, then we need to make + * note of it. Because we already consumed our entry. + */ + if (s->full) { + data->failed = 1; + data->cpu = cpu; + } else + data->failed = 0; + } + return ret; } static enum print_line_t print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s, - struct trace_entry *ent, struct trace_iterator *iter) + struct trace_entry *ent, struct trace_iterator *iter, + u32 flags) { unsigned long long duration = trace->rettime - trace->calltime; struct fgraph_data *data = iter->private; pid_t pid = ent->pid; int cpu = iter->cpu; + int func_match = 1; int ret; int i; + if (check_irq_return(iter, flags, trace->depth)) + return TRACE_TYPE_HANDLED; + if (data) { + struct fgraph_cpu_data *cpu_data; int cpu = iter->cpu; - int *depth = &(per_cpu_ptr(data, cpu)->depth); + + cpu_data = per_cpu_ptr(data->cpu_data, cpu); /* * Comments display at + 1 to depth. This is the * return from a function, we now want the comments * to display at the same level of the bracket. */ - *depth = trace->depth - 1; + cpu_data->depth = trace->depth - 1; + + if (trace->depth < FTRACE_RETFUNC_DEPTH) { + if (cpu_data->enter_funcs[trace->depth] != trace->func) + func_match = 0; + cpu_data->enter_funcs[trace->depth] = 0; + } } - if (print_graph_prologue(iter, s, 0, 0)) + if (print_graph_prologue(iter, s, 0, 0, flags)) return TRACE_TYPE_PARTIAL_LINE; - /* Overhead */ - ret = print_graph_overhead(duration, s); - if (!ret) + /* Overhead and duration */ + ret = print_graph_duration(duration, s, flags); + if (ret == TRACE_TYPE_PARTIAL_LINE) return TRACE_TYPE_PARTIAL_LINE; - /* Duration */ - if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) { - ret = print_graph_duration(duration, s); - if (ret == TRACE_TYPE_PARTIAL_LINE) - return TRACE_TYPE_PARTIAL_LINE; - } - /* Closing brace */ for (i = 0; i < trace->depth * TRACE_GRAPH_INDENT; i++) { - ret = trace_seq_printf(s, " "); + ret = trace_seq_putc(s, ' '); if (!ret) return TRACE_TYPE_PARTIAL_LINE; } - ret = trace_seq_printf(s, "}\n"); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; + /* + * If the return function does not have a matching entry, + * then the entry was lost. Instead of just printing + * the '}' and letting the user guess what function this + * belongs to, write out the function name. Always do + * that if the funcgraph-tail option is enabled. + */ + if (func_match && !(flags & TRACE_GRAPH_PRINT_TAIL)) { + ret = trace_seq_puts(s, "}\n"); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + } else { + ret = trace_seq_printf(s, "} /* %ps */\n", (void *)trace->func); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + } /* Overrun */ - if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERRUN) { + if (flags & TRACE_GRAPH_PRINT_OVERRUN) { ret = trace_seq_printf(s, " (Overruns: %lu)\n", trace->overrun); if (!ret) return TRACE_TYPE_PARTIAL_LINE; } - ret = print_graph_irq(iter, trace->func, TRACE_GRAPH_RET, cpu, pid); + ret = print_graph_irq(iter, trace->func, TRACE_GRAPH_RET, + cpu, pid, flags); if (ret == TRACE_TYPE_PARTIAL_LINE) return TRACE_TYPE_PARTIAL_LINE; @@ -759,8 +1199,8 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s, } static enum print_line_t -print_graph_comment(struct trace_seq *s, struct trace_entry *ent, - struct trace_iterator *iter) +print_graph_comment(struct trace_seq *s, struct trace_entry *ent, + struct trace_iterator *iter, u32 flags) { unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); struct fgraph_data *data = iter->private; @@ -770,33 +1210,26 @@ print_graph_comment(struct trace_seq *s, struct trace_entry *ent, int i; if (data) - depth = per_cpu_ptr(data, iter->cpu)->depth; + depth = per_cpu_ptr(data->cpu_data, iter->cpu)->depth; - if (print_graph_prologue(iter, s, 0, 0)) - return TRACE_TYPE_PARTIAL_LINE; - - /* No overhead */ - ret = print_graph_overhead(-1, s); - if (!ret) + if (print_graph_prologue(iter, s, 0, 0, flags)) return TRACE_TYPE_PARTIAL_LINE; /* No time */ - if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) { - ret = trace_seq_printf(s, " | "); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - } + ret = print_graph_duration(0, s, flags | FLAGS_FILL_FULL); + if (ret != TRACE_TYPE_HANDLED) + return ret; /* Indentation */ if (depth > 0) for (i = 0; i < (depth + 1) * TRACE_GRAPH_INDENT; i++) { - ret = trace_seq_printf(s, " "); + ret = trace_seq_putc(s, ' '); if (!ret) return TRACE_TYPE_PARTIAL_LINE; } /* The comment */ - ret = trace_seq_printf(s, "/* "); + ret = trace_seq_puts(s, "/* "); if (!ret) return TRACE_TYPE_PARTIAL_LINE; @@ -816,7 +1249,7 @@ print_graph_comment(struct trace_seq *s, struct trace_entry *ent, if (!event) return TRACE_TYPE_UNHANDLED; - ret = event->trace(iter, sym_flags); + ret = event->funcs->trace(iter, sym_flags, event); if (ret != TRACE_TYPE_HANDLED) return ret; } @@ -827,7 +1260,7 @@ print_graph_comment(struct trace_seq *s, struct trace_entry *ent, s->len--; } - ret = trace_seq_printf(s, " */\n"); + ret = trace_seq_puts(s, " */\n"); if (!ret) return TRACE_TYPE_PARTIAL_LINE; @@ -836,98 +1269,315 @@ print_graph_comment(struct trace_seq *s, struct trace_entry *ent, enum print_line_t -print_graph_function(struct trace_iterator *iter) +print_graph_function_flags(struct trace_iterator *iter, u32 flags) { + struct ftrace_graph_ent_entry *field; + struct fgraph_data *data = iter->private; struct trace_entry *entry = iter->ent; struct trace_seq *s = &iter->seq; + int cpu = iter->cpu; + int ret; + + if (data && per_cpu_ptr(data->cpu_data, cpu)->ignore) { + per_cpu_ptr(data->cpu_data, cpu)->ignore = 0; + return TRACE_TYPE_HANDLED; + } + + /* + * If the last output failed, there's a possibility we need + * to print out the missing entry which would never go out. + */ + if (data && data->failed) { + field = &data->ent; + iter->cpu = data->cpu; + ret = print_graph_entry(field, s, iter, flags); + if (ret == TRACE_TYPE_HANDLED && iter->cpu != cpu) { + per_cpu_ptr(data->cpu_data, iter->cpu)->ignore = 1; + ret = TRACE_TYPE_NO_CONSUME; + } + iter->cpu = cpu; + return ret; + } switch (entry->type) { case TRACE_GRAPH_ENT: { - struct ftrace_graph_ent_entry *field; + /* + * print_graph_entry() may consume the current event, + * thus @field may become invalid, so we need to save it. + * sizeof(struct ftrace_graph_ent_entry) is very small, + * it can be safely saved at the stack. + */ + struct ftrace_graph_ent_entry saved; trace_assign_type(field, entry); - return print_graph_entry(field, s, iter); + saved = *field; + return print_graph_entry(&saved, s, iter, flags); } case TRACE_GRAPH_RET: { struct ftrace_graph_ret_entry *field; trace_assign_type(field, entry); - return print_graph_return(&field->ret, s, entry, iter); + return print_graph_return(&field->ret, s, entry, iter, flags); } + case TRACE_STACK: + case TRACE_FN: + /* dont trace stack and functions as comments */ + return TRACE_TYPE_UNHANDLED; + default: - return print_graph_comment(s, entry, iter); + return print_graph_comment(s, entry, iter, flags); } return TRACE_TYPE_HANDLED; } -static void print_graph_headers(struct seq_file *s) +static enum print_line_t +print_graph_function(struct trace_iterator *iter) +{ + return print_graph_function_flags(iter, tracer_flags.val); +} + +static enum print_line_t +print_graph_function_event(struct trace_iterator *iter, int flags, + struct trace_event *event) +{ + return print_graph_function(iter); +} + +static void print_lat_header(struct seq_file *s, u32 flags) +{ + static const char spaces[] = " " /* 16 spaces */ + " " /* 4 spaces */ + " "; /* 17 spaces */ + int size = 0; + + if (flags & TRACE_GRAPH_PRINT_ABS_TIME) + size += 16; + if (flags & TRACE_GRAPH_PRINT_CPU) + size += 4; + if (flags & TRACE_GRAPH_PRINT_PROC) + size += 17; + + seq_printf(s, "#%.*s _-----=> irqs-off \n", size, spaces); + seq_printf(s, "#%.*s / _----=> need-resched \n", size, spaces); + seq_printf(s, "#%.*s| / _---=> hardirq/softirq \n", size, spaces); + seq_printf(s, "#%.*s|| / _--=> preempt-depth \n", size, spaces); + seq_printf(s, "#%.*s||| / \n", size, spaces); +} + +static void __print_graph_headers_flags(struct seq_file *s, u32 flags) { + int lat = trace_flags & TRACE_ITER_LATENCY_FMT; + + if (lat) + print_lat_header(s, flags); + /* 1st line */ - seq_printf(s, "# "); - if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME) + seq_printf(s, "#"); + if (flags & TRACE_GRAPH_PRINT_ABS_TIME) seq_printf(s, " TIME "); - if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) - seq_printf(s, "CPU"); - if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) - seq_printf(s, " TASK/PID "); - if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) + if (flags & TRACE_GRAPH_PRINT_CPU) + seq_printf(s, " CPU"); + if (flags & TRACE_GRAPH_PRINT_PROC) + seq_printf(s, " TASK/PID "); + if (lat) + seq_printf(s, "||||"); + if (flags & TRACE_GRAPH_PRINT_DURATION) seq_printf(s, " DURATION "); seq_printf(s, " FUNCTION CALLS\n"); /* 2nd line */ - seq_printf(s, "# "); - if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME) + seq_printf(s, "#"); + if (flags & TRACE_GRAPH_PRINT_ABS_TIME) seq_printf(s, " | "); - if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) - seq_printf(s, "| "); - if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) - seq_printf(s, " | | "); - if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) + if (flags & TRACE_GRAPH_PRINT_CPU) + seq_printf(s, " | "); + if (flags & TRACE_GRAPH_PRINT_PROC) + seq_printf(s, " | | "); + if (lat) + seq_printf(s, "||||"); + if (flags & TRACE_GRAPH_PRINT_DURATION) seq_printf(s, " | | "); seq_printf(s, " | | | |\n"); } -static void graph_trace_open(struct trace_iterator *iter) +void print_graph_headers(struct seq_file *s) +{ + print_graph_headers_flags(s, tracer_flags.val); +} + +void print_graph_headers_flags(struct seq_file *s, u32 flags) +{ + struct trace_iterator *iter = s->private; + + if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) + return; + + if (trace_flags & TRACE_ITER_LATENCY_FMT) { + /* print nothing if the buffers are empty */ + if (trace_empty(iter)) + return; + + print_trace_header(s, iter); + } + + __print_graph_headers_flags(s, flags); +} + +void graph_trace_open(struct trace_iterator *iter) { /* pid and depth on the last trace processed */ - struct fgraph_data *data = alloc_percpu(struct fgraph_data); + struct fgraph_data *data; int cpu; + iter->private = NULL; + + data = kzalloc(sizeof(*data), GFP_KERNEL); if (!data) - pr_warning("function graph tracer: not enough memory\n"); - else - for_each_possible_cpu(cpu) { - pid_t *pid = &(per_cpu_ptr(data, cpu)->last_pid); - int *depth = &(per_cpu_ptr(data, cpu)->depth); - *pid = -1; - *depth = 0; - } + goto out_err; + + data->cpu_data = alloc_percpu(struct fgraph_cpu_data); + if (!data->cpu_data) + goto out_err_free; + + for_each_possible_cpu(cpu) { + pid_t *pid = &(per_cpu_ptr(data->cpu_data, cpu)->last_pid); + int *depth = &(per_cpu_ptr(data->cpu_data, cpu)->depth); + int *ignore = &(per_cpu_ptr(data->cpu_data, cpu)->ignore); + int *depth_irq = &(per_cpu_ptr(data->cpu_data, cpu)->depth_irq); + + *pid = -1; + *depth = 0; + *ignore = 0; + *depth_irq = -1; + } iter->private = data; + + return; + + out_err_free: + kfree(data); + out_err: + pr_warning("function graph tracer: not enough memory\n"); } -static void graph_trace_close(struct trace_iterator *iter) +void graph_trace_close(struct trace_iterator *iter) { - free_percpu(iter->private); + struct fgraph_data *data = iter->private; + + if (data) { + free_percpu(data->cpu_data); + kfree(data); + } } -static struct tracer graph_trace __read_mostly = { +static int +func_graph_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) +{ + if (bit == TRACE_GRAPH_PRINT_IRQS) + ftrace_graph_skip_irqs = !set; + + return 0; +} + +static struct trace_event_functions graph_functions = { + .trace = print_graph_function_event, +}; + +static struct trace_event graph_trace_entry_event = { + .type = TRACE_GRAPH_ENT, + .funcs = &graph_functions, +}; + +static struct trace_event graph_trace_ret_event = { + .type = TRACE_GRAPH_RET, + .funcs = &graph_functions +}; + +static struct tracer graph_trace __tracer_data = { .name = "function_graph", .open = graph_trace_open, + .pipe_open = graph_trace_open, .close = graph_trace_close, - .wait_pipe = poll_wait_pipe, + .pipe_close = graph_trace_close, .init = graph_trace_init, .reset = graph_trace_reset, .print_line = print_graph_function, .print_header = print_graph_headers, .flags = &tracer_flags, + .set_flag = func_graph_set_flag, #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_function_graph, #endif }; + +static ssize_t +graph_depth_write(struct file *filp, const char __user *ubuf, size_t cnt, + loff_t *ppos) +{ + unsigned long val; + int ret; + + ret = kstrtoul_from_user(ubuf, cnt, 10, &val); + if (ret) + return ret; + + max_depth = val; + + *ppos += cnt; + + return cnt; +} + +static ssize_t +graph_depth_read(struct file *filp, char __user *ubuf, size_t cnt, + loff_t *ppos) +{ + char buf[15]; /* More than enough to hold UINT_MAX + "\n"*/ + int n; + + n = sprintf(buf, "%d\n", max_depth); + + return simple_read_from_buffer(ubuf, cnt, ppos, buf, n); +} + +static const struct file_operations graph_depth_fops = { + .open = tracing_open_generic, + .write = graph_depth_write, + .read = graph_depth_read, + .llseek = generic_file_llseek, +}; + +static __init int init_graph_debugfs(void) +{ + struct dentry *d_tracer; + + d_tracer = tracing_init_dentry(); + if (!d_tracer) + return 0; + + trace_create_file("max_graph_depth", 0644, d_tracer, + NULL, &graph_depth_fops); + + return 0; +} +fs_initcall(init_graph_debugfs); + static __init int init_graph_trace(void) { + max_bytes_for_cpu = snprintf(NULL, 0, "%d", nr_cpu_ids - 1); + + if (!register_ftrace_event(&graph_trace_entry_event)) { + pr_warning("Warning: could not register graph trace events\n"); + return 1; + } + + if (!register_ftrace_event(&graph_trace_ret_event)) { + pr_warning("Warning: could not register graph trace events\n"); + return 1; + } + return register_tracer(&graph_trace); } -device_initcall(init_graph_trace); +core_initcall(init_graph_trace); diff --git a/kernel/trace/trace_hw_branches.c b/kernel/trace/trace_hw_branches.c deleted file mode 100644 index ca7d7c4d0c2..00000000000 --- a/kernel/trace/trace_hw_branches.c +++ /dev/null @@ -1,309 +0,0 @@ -/* - * h/w branch tracer for x86 based on BTS - * - * Copyright (C) 2008-2009 Intel Corporation. - * Markus Metzger <markus.t.metzger@gmail.com>, 2008-2009 - */ -#include <linux/kallsyms.h> -#include <linux/debugfs.h> -#include <linux/ftrace.h> -#include <linux/module.h> -#include <linux/cpu.h> -#include <linux/smp.h> -#include <linux/fs.h> - -#include <asm/ds.h> - -#include "trace_output.h" -#include "trace.h" - - -#define BTS_BUFFER_SIZE (1 << 13) - -static DEFINE_PER_CPU(struct bts_tracer *, tracer); -static DEFINE_PER_CPU(unsigned char[BTS_BUFFER_SIZE], buffer); - -#define this_tracer per_cpu(tracer, smp_processor_id()) - -static int trace_hw_branches_enabled __read_mostly; -static int trace_hw_branches_suspended __read_mostly; -static struct trace_array *hw_branch_trace __read_mostly; - - -static void bts_trace_init_cpu(int cpu) -{ - per_cpu(tracer, cpu) = - ds_request_bts_cpu(cpu, per_cpu(buffer, cpu), BTS_BUFFER_SIZE, - NULL, (size_t)-1, BTS_KERNEL); - - if (IS_ERR(per_cpu(tracer, cpu))) - per_cpu(tracer, cpu) = NULL; -} - -static int bts_trace_init(struct trace_array *tr) -{ - int cpu; - - hw_branch_trace = tr; - trace_hw_branches_enabled = 0; - - get_online_cpus(); - for_each_online_cpu(cpu) { - bts_trace_init_cpu(cpu); - - if (likely(per_cpu(tracer, cpu))) - trace_hw_branches_enabled = 1; - } - trace_hw_branches_suspended = 0; - put_online_cpus(); - - /* If we could not enable tracing on a single cpu, we fail. */ - return trace_hw_branches_enabled ? 0 : -EOPNOTSUPP; -} - -static void bts_trace_reset(struct trace_array *tr) -{ - int cpu; - - get_online_cpus(); - for_each_online_cpu(cpu) { - if (likely(per_cpu(tracer, cpu))) { - ds_release_bts(per_cpu(tracer, cpu)); - per_cpu(tracer, cpu) = NULL; - } - } - trace_hw_branches_enabled = 0; - trace_hw_branches_suspended = 0; - put_online_cpus(); -} - -static void bts_trace_start(struct trace_array *tr) -{ - int cpu; - - get_online_cpus(); - for_each_online_cpu(cpu) - if (likely(per_cpu(tracer, cpu))) - ds_resume_bts(per_cpu(tracer, cpu)); - trace_hw_branches_suspended = 0; - put_online_cpus(); -} - -static void bts_trace_stop(struct trace_array *tr) -{ - int cpu; - - get_online_cpus(); - for_each_online_cpu(cpu) - if (likely(per_cpu(tracer, cpu))) - ds_suspend_bts(per_cpu(tracer, cpu)); - trace_hw_branches_suspended = 1; - put_online_cpus(); -} - -static int __cpuinit bts_hotcpu_handler(struct notifier_block *nfb, - unsigned long action, void *hcpu) -{ - int cpu = (long)hcpu; - - switch (action) { - case CPU_ONLINE: - case CPU_DOWN_FAILED: - /* The notification is sent with interrupts enabled. */ - if (trace_hw_branches_enabled) { - bts_trace_init_cpu(cpu); - - if (trace_hw_branches_suspended && - likely(per_cpu(tracer, cpu))) - ds_suspend_bts(per_cpu(tracer, cpu)); - } - break; - - case CPU_DOWN_PREPARE: - /* The notification is sent with interrupts enabled. */ - if (likely(per_cpu(tracer, cpu))) { - ds_release_bts(per_cpu(tracer, cpu)); - per_cpu(tracer, cpu) = NULL; - } - } - - return NOTIFY_DONE; -} - -static struct notifier_block bts_hotcpu_notifier __cpuinitdata = { - .notifier_call = bts_hotcpu_handler -}; - -static void bts_trace_print_header(struct seq_file *m) -{ - seq_puts(m, "# CPU# TO <- FROM\n"); -} - -static enum print_line_t bts_trace_print_line(struct trace_iterator *iter) -{ - unsigned long symflags = TRACE_ITER_SYM_OFFSET; - struct trace_entry *entry = iter->ent; - struct trace_seq *seq = &iter->seq; - struct hw_branch_entry *it; - - trace_assign_type(it, entry); - - if (entry->type == TRACE_HW_BRANCHES) { - if (trace_seq_printf(seq, "%4d ", iter->cpu) && - seq_print_ip_sym(seq, it->to, symflags) && - trace_seq_printf(seq, "\t <- ") && - seq_print_ip_sym(seq, it->from, symflags) && - trace_seq_printf(seq, "\n")) - return TRACE_TYPE_HANDLED; - return TRACE_TYPE_PARTIAL_LINE;; - } - return TRACE_TYPE_UNHANDLED; -} - -void trace_hw_branch(u64 from, u64 to) -{ - struct ftrace_event_call *call = &event_hw_branch; - struct trace_array *tr = hw_branch_trace; - struct ring_buffer_event *event; - struct hw_branch_entry *entry; - unsigned long irq1; - int cpu; - - if (unlikely(!tr)) - return; - - if (unlikely(!trace_hw_branches_enabled)) - return; - - local_irq_save(irq1); - cpu = raw_smp_processor_id(); - if (atomic_inc_return(&tr->data[cpu]->disabled) != 1) - goto out; - - event = trace_buffer_lock_reserve(tr, TRACE_HW_BRANCHES, - sizeof(*entry), 0, 0); - if (!event) - goto out; - entry = ring_buffer_event_data(event); - tracing_generic_entry_update(&entry->ent, 0, from); - entry->ent.type = TRACE_HW_BRANCHES; - entry->from = from; - entry->to = to; - if (!filter_check_discard(call, entry, tr->buffer, event)) - trace_buffer_unlock_commit(tr, event, 0, 0); - - out: - atomic_dec(&tr->data[cpu]->disabled); - local_irq_restore(irq1); -} - -static void trace_bts_at(const struct bts_trace *trace, void *at) -{ - struct bts_struct bts; - int err = 0; - - WARN_ON_ONCE(!trace->read); - if (!trace->read) - return; - - err = trace->read(this_tracer, at, &bts); - if (err < 0) - return; - - switch (bts.qualifier) { - case BTS_BRANCH: - trace_hw_branch(bts.variant.lbr.from, bts.variant.lbr.to); - break; - } -} - -/* - * Collect the trace on the current cpu and write it into the ftrace buffer. - * - * pre: tracing must be suspended on the current cpu - */ -static void trace_bts_cpu(void *arg) -{ - struct trace_array *tr = (struct trace_array *)arg; - const struct bts_trace *trace; - unsigned char *at; - - if (unlikely(!tr)) - return; - - if (unlikely(atomic_read(&tr->data[raw_smp_processor_id()]->disabled))) - return; - - if (unlikely(!this_tracer)) - return; - - trace = ds_read_bts(this_tracer); - if (!trace) - return; - - for (at = trace->ds.top; (void *)at < trace->ds.end; - at += trace->ds.size) - trace_bts_at(trace, at); - - for (at = trace->ds.begin; (void *)at < trace->ds.top; - at += trace->ds.size) - trace_bts_at(trace, at); -} - -static void trace_bts_prepare(struct trace_iterator *iter) -{ - int cpu; - - get_online_cpus(); - for_each_online_cpu(cpu) - if (likely(per_cpu(tracer, cpu))) - ds_suspend_bts(per_cpu(tracer, cpu)); - /* - * We need to collect the trace on the respective cpu since ftrace - * implicitly adds the record for the current cpu. - * Once that is more flexible, we could collect the data from any cpu. - */ - on_each_cpu(trace_bts_cpu, iter->tr, 1); - - for_each_online_cpu(cpu) - if (likely(per_cpu(tracer, cpu))) - ds_resume_bts(per_cpu(tracer, cpu)); - put_online_cpus(); -} - -static void trace_bts_close(struct trace_iterator *iter) -{ - tracing_reset_online_cpus(iter->tr); -} - -void trace_hw_branch_oops(void) -{ - if (this_tracer) { - ds_suspend_bts_noirq(this_tracer); - trace_bts_cpu(hw_branch_trace); - ds_resume_bts_noirq(this_tracer); - } -} - -struct tracer bts_tracer __read_mostly = -{ - .name = "hw-branch-tracer", - .init = bts_trace_init, - .reset = bts_trace_reset, - .print_header = bts_trace_print_header, - .print_line = bts_trace_print_line, - .start = bts_trace_start, - .stop = bts_trace_stop, - .open = trace_bts_prepare, - .close = trace_bts_close, -#ifdef CONFIG_FTRACE_SELFTEST - .selftest = trace_selftest_startup_hw_branches, -#endif /* CONFIG_FTRACE_SELFTEST */ -}; - -__init static int init_bts_trace(void) -{ - register_hotcpu_notifier(&bts_hotcpu_notifier); - return register_tracer(&bts_tracer); -} -device_initcall(init_bts_trace); diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index b923d13e2fa..9bb104f748d 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -7,7 +7,7 @@ * From code in the latency_tracer, that is: * * Copyright (C) 2004-2006 Ingo Molnar - * Copyright (C) 2004 William Lee Irwin III + * Copyright (C) 2004 Nadia Yvette Chambers */ #include <linux/kallsyms.h> #include <linux/debugfs.h> @@ -23,7 +23,7 @@ static int tracer_enabled __read_mostly; static DEFINE_PER_CPU(int, tracing_cpu); -static DEFINE_SPINLOCK(max_trace_lock); +static DEFINE_RAW_SPINLOCK(max_trace_lock); enum { TRACER_IRQS_OFF = (1 << 1), @@ -32,7 +32,11 @@ enum { static int trace_type __read_mostly; -static int save_lat_flag; +static int save_flags; +static bool function_enabled; + +static void stop_irqsoff_tracer(struct trace_array *tr, int graph); +static int start_irqsoff_tracer(struct trace_array *tr, int graph); #ifdef CONFIG_PREEMPT_TRACER static inline int @@ -55,26 +59,51 @@ irq_trace(void) # define irq_trace() (0) #endif +#define TRACE_DISPLAY_GRAPH 1 + +static struct tracer_opt trace_opts[] = { +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + /* display latency trace as call graph */ + { TRACER_OPT(display-graph, TRACE_DISPLAY_GRAPH) }, +#endif + { } /* Empty entry */ +}; + +static struct tracer_flags tracer_flags = { + .val = 0, + .opts = trace_opts, +}; + +#define is_graph() (tracer_flags.val & TRACE_DISPLAY_GRAPH) + /* * Sequence count - we record it when starting a measurement and * skip the latency if the sequence has changed - some other section * did a maximum and could disturb our measurement with serial console * printouts, etc. Truly coinciding maximum latencies should be rare - * and what happens together happens separately as well, so this doesnt + * and what happens together happens separately as well, so this doesn't * decrease the validity of the maximum found: */ static __cacheline_aligned_in_smp unsigned long max_sequence; #ifdef CONFIG_FUNCTION_TRACER /* - * irqsoff uses its own tracer function to keep the overhead down: + * Prologue for the preempt and irqs off function tracers. + * + * Returns 1 if it is OK to continue, and data->disabled is + * incremented. + * 0 if the trace is to be ignored, and data->disabled + * is kept the same. + * + * Note, this function is also used outside this ifdef but + * inside the #ifdef of the function graph tracer below. + * This is OK, since the function graph tracer is + * dependent on the function tracer. */ -static void -irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip) +static int func_prolog_dec(struct trace_array *tr, + struct trace_array_cpu **data, + unsigned long *flags) { - struct trace_array *tr = irqsoff_trace; - struct trace_array_cpu *data; - unsigned long flags; long disabled; int cpu; @@ -86,38 +115,195 @@ irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip) */ cpu = raw_smp_processor_id(); if (likely(!per_cpu(tracing_cpu, cpu))) - return; + return 0; - local_save_flags(flags); + local_save_flags(*flags); /* slight chance to get a false positive on tracing_cpu */ - if (!irqs_disabled_flags(flags)) - return; + if (!irqs_disabled_flags(*flags)) + return 0; - data = tr->data[cpu]; - disabled = atomic_inc_return(&data->disabled); + *data = per_cpu_ptr(tr->trace_buffer.data, cpu); + disabled = atomic_inc_return(&(*data)->disabled); if (likely(disabled == 1)) - trace_function(tr, ip, parent_ip, flags, preempt_count()); + return 1; + + atomic_dec(&(*data)->disabled); + + return 0; +} + +/* + * irqsoff uses its own tracer function to keep the overhead down: + */ +static void +irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct pt_regs *pt_regs) +{ + struct trace_array *tr = irqsoff_trace; + struct trace_array_cpu *data; + unsigned long flags; + + if (!func_prolog_dec(tr, &data, &flags)) + return; + + trace_function(tr, ip, parent_ip, flags, preempt_count()); atomic_dec(&data->disabled); } +#endif /* CONFIG_FUNCTION_TRACER */ -static struct ftrace_ops trace_ops __read_mostly = +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +static int +irqsoff_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) { - .func = irqsoff_tracer_call, -}; + int cpu; + + if (!(bit & TRACE_DISPLAY_GRAPH)) + return -EINVAL; + + if (!(is_graph() ^ set)) + return 0; + + stop_irqsoff_tracer(irqsoff_trace, !set); + + for_each_possible_cpu(cpu) + per_cpu(tracing_cpu, cpu) = 0; + + tr->max_latency = 0; + tracing_reset_online_cpus(&irqsoff_trace->trace_buffer); + + return start_irqsoff_tracer(irqsoff_trace, set); +} + +static int irqsoff_graph_entry(struct ftrace_graph_ent *trace) +{ + struct trace_array *tr = irqsoff_trace; + struct trace_array_cpu *data; + unsigned long flags; + int ret; + int pc; + + if (!func_prolog_dec(tr, &data, &flags)) + return 0; + + pc = preempt_count(); + ret = __trace_graph_entry(tr, trace, flags, pc); + atomic_dec(&data->disabled); + + return ret; +} + +static void irqsoff_graph_return(struct ftrace_graph_ret *trace) +{ + struct trace_array *tr = irqsoff_trace; + struct trace_array_cpu *data; + unsigned long flags; + int pc; + + if (!func_prolog_dec(tr, &data, &flags)) + return; + + pc = preempt_count(); + __trace_graph_return(tr, trace, flags, pc); + atomic_dec(&data->disabled); +} + +static void irqsoff_trace_open(struct trace_iterator *iter) +{ + if (is_graph()) + graph_trace_open(iter); + +} + +static void irqsoff_trace_close(struct trace_iterator *iter) +{ + if (iter->private) + graph_trace_close(iter); +} + +#define GRAPH_TRACER_FLAGS (TRACE_GRAPH_PRINT_CPU | \ + TRACE_GRAPH_PRINT_PROC | \ + TRACE_GRAPH_PRINT_ABS_TIME | \ + TRACE_GRAPH_PRINT_DURATION) + +static enum print_line_t irqsoff_print_line(struct trace_iterator *iter) +{ + /* + * In graph mode call the graph tracer output function, + * otherwise go with the TRACE_FN event handler + */ + if (is_graph()) + return print_graph_function_flags(iter, GRAPH_TRACER_FLAGS); + + return TRACE_TYPE_UNHANDLED; +} + +static void irqsoff_print_header(struct seq_file *s) +{ + if (is_graph()) + print_graph_headers_flags(s, GRAPH_TRACER_FLAGS); + else + trace_default_header(s); +} + +static void +__trace_function(struct trace_array *tr, + unsigned long ip, unsigned long parent_ip, + unsigned long flags, int pc) +{ + if (is_graph()) + trace_graph_function(tr, ip, parent_ip, flags, pc); + else + trace_function(tr, ip, parent_ip, flags, pc); +} + +#else +#define __trace_function trace_function + +static int +irqsoff_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) +{ + return -EINVAL; +} + +static int irqsoff_graph_entry(struct ftrace_graph_ent *trace) +{ + return -1; +} + +static enum print_line_t irqsoff_print_line(struct trace_iterator *iter) +{ + return TRACE_TYPE_UNHANDLED; +} + +static void irqsoff_graph_return(struct ftrace_graph_ret *trace) { } +static void irqsoff_trace_open(struct trace_iterator *iter) { } +static void irqsoff_trace_close(struct trace_iterator *iter) { } + +#ifdef CONFIG_FUNCTION_TRACER +static void irqsoff_print_header(struct seq_file *s) +{ + trace_default_header(s); +} +#else +static void irqsoff_print_header(struct seq_file *s) +{ + trace_latency_header(s); +} #endif /* CONFIG_FUNCTION_TRACER */ +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ /* * Should this new latency be reported/recorded? */ -static int report_latency(cycle_t delta) +static int report_latency(struct trace_array *tr, cycle_t delta) { if (tracing_thresh) { if (delta < tracing_thresh) return 0; } else { - if (delta <= tracing_max_latency) + if (delta <= tr->max_latency) return 0; } return 1; @@ -129,15 +315,10 @@ check_critical_timing(struct trace_array *tr, unsigned long parent_ip, int cpu) { - unsigned long latency, t0, t1; cycle_t T0, T1, delta; unsigned long flags; int pc; - /* - * usecs conversion is slow so we try to delay the conversion - * as long as possible: - */ T0 = data->preempt_timestamp; T1 = ftrace_now(cpu); delta = T1-T0; @@ -146,40 +327,38 @@ check_critical_timing(struct trace_array *tr, pc = preempt_count(); - if (!report_latency(delta)) + if (!report_latency(tr, delta)) goto out; - spin_lock_irqsave(&max_trace_lock, flags); + raw_spin_lock_irqsave(&max_trace_lock, flags); /* check if we are still the max latency */ - if (!report_latency(delta)) + if (!report_latency(tr, delta)) goto out_unlock; - trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc); - - latency = nsecs_to_usecs(delta); + __trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc); + /* Skip 5 functions to get to the irq/preempt enable function */ + __trace_stack(tr, flags, 5, pc); if (data->critical_sequence != max_sequence) goto out_unlock; - tracing_max_latency = delta; - t0 = nsecs_to_usecs(T0); - t1 = nsecs_to_usecs(T1); - data->critical_end = parent_ip; - update_max_tr_single(tr, current, cpu); + if (likely(!is_tracing_stopped())) { + tr->max_latency = delta; + update_max_tr_single(tr, current, cpu); + } max_sequence++; out_unlock: - spin_unlock_irqrestore(&max_trace_lock, flags); + raw_spin_unlock_irqrestore(&max_trace_lock, flags); out: data->critical_sequence = max_sequence; data->preempt_timestamp = ftrace_now(cpu); - tracing_reset(tr, cpu); - trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc); + __trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc); } static inline void @@ -190,7 +369,7 @@ start_critical_timing(unsigned long ip, unsigned long parent_ip) struct trace_array_cpu *data; unsigned long flags; - if (likely(!tracer_enabled)) + if (!tracer_enabled || !tracing_is_enabled()) return; cpu = raw_smp_processor_id(); @@ -198,7 +377,7 @@ start_critical_timing(unsigned long ip, unsigned long parent_ip) if (per_cpu(tracing_cpu, cpu)) return; - data = tr->data[cpu]; + data = per_cpu_ptr(tr->trace_buffer.data, cpu); if (unlikely(!data) || atomic_read(&data->disabled)) return; @@ -208,11 +387,10 @@ start_critical_timing(unsigned long ip, unsigned long parent_ip) data->critical_sequence = max_sequence; data->preempt_timestamp = ftrace_now(cpu); data->critical_start = parent_ip ? : ip; - tracing_reset(tr, cpu); local_save_flags(flags); - trace_function(tr, ip, parent_ip, flags, preempt_count()); + __trace_function(tr, ip, parent_ip, flags, preempt_count()); per_cpu(tracing_cpu, cpu) = 1; @@ -234,10 +412,10 @@ stop_critical_timing(unsigned long ip, unsigned long parent_ip) else return; - if (!tracer_enabled) + if (!tracer_enabled || !tracing_is_enabled()) return; - data = tr->data[cpu]; + data = per_cpu_ptr(tr->trace_buffer.data, cpu); if (unlikely(!data) || !data->critical_start || atomic_read(&data->disabled)) @@ -246,7 +424,7 @@ stop_critical_timing(unsigned long ip, unsigned long parent_ip) atomic_inc(&data->disabled); local_save_flags(flags); - trace_function(tr, ip, parent_ip, flags, preempt_count()); + __trace_function(tr, ip, parent_ip, flags, preempt_count()); check_critical_timing(tr, data, parent_ip ? : ip, cpu); data->critical_start = 0; atomic_dec(&data->disabled); @@ -287,14 +465,6 @@ void time_hardirqs_off(unsigned long a0, unsigned long a1) * Stubs: */ -void early_boot_irqs_off(void) -{ -} - -void early_boot_irqs_on(void) -{ -} - void trace_softirqs_on(unsigned long ip) { } @@ -324,14 +494,14 @@ void trace_hardirqs_off(void) } EXPORT_SYMBOL(trace_hardirqs_off); -void trace_hardirqs_on_caller(unsigned long caller_addr) +__visible void trace_hardirqs_on_caller(unsigned long caller_addr) { if (!preempt_trace() && irq_trace()) stop_critical_timing(CALLER_ADDR0, caller_addr); } EXPORT_SYMBOL(trace_hardirqs_on_caller); -void trace_hardirqs_off_caller(unsigned long caller_addr) +__visible void trace_hardirqs_off_caller(unsigned long caller_addr) { if (!preempt_trace() && irq_trace()) start_critical_timing(CALLER_ADDR0, caller_addr); @@ -344,50 +514,131 @@ EXPORT_SYMBOL(trace_hardirqs_off_caller); #ifdef CONFIG_PREEMPT_TRACER void trace_preempt_on(unsigned long a0, unsigned long a1) { - if (preempt_trace()) + if (preempt_trace() && !irq_trace()) stop_critical_timing(a0, a1); } void trace_preempt_off(unsigned long a0, unsigned long a1) { - if (preempt_trace()) + if (preempt_trace() && !irq_trace()) start_critical_timing(a0, a1); } #endif /* CONFIG_PREEMPT_TRACER */ -static void start_irqsoff_tracer(struct trace_array *tr) +static int register_irqsoff_function(struct trace_array *tr, int graph, int set) { - register_ftrace_function(&trace_ops); - if (tracing_is_enabled()) + int ret; + + /* 'set' is set if TRACE_ITER_FUNCTION is about to be set */ + if (function_enabled || (!set && !(trace_flags & TRACE_ITER_FUNCTION))) + return 0; + + if (graph) + ret = register_ftrace_graph(&irqsoff_graph_return, + &irqsoff_graph_entry); + else + ret = register_ftrace_function(tr->ops); + + if (!ret) + function_enabled = true; + + return ret; +} + +static void unregister_irqsoff_function(struct trace_array *tr, int graph) +{ + if (!function_enabled) + return; + + if (graph) + unregister_ftrace_graph(); + else + unregister_ftrace_function(tr->ops); + + function_enabled = false; +} + +static void irqsoff_function_set(struct trace_array *tr, int set) +{ + if (set) + register_irqsoff_function(tr, is_graph(), 1); + else + unregister_irqsoff_function(tr, is_graph()); +} + +static int irqsoff_flag_changed(struct trace_array *tr, u32 mask, int set) +{ + struct tracer *tracer = tr->current_trace; + + if (mask & TRACE_ITER_FUNCTION) + irqsoff_function_set(tr, set); + + return trace_keep_overwrite(tracer, mask, set); +} + +static int start_irqsoff_tracer(struct trace_array *tr, int graph) +{ + int ret; + + ret = register_irqsoff_function(tr, graph, 0); + + if (!ret && tracing_is_enabled()) tracer_enabled = 1; else tracer_enabled = 0; + + return ret; } -static void stop_irqsoff_tracer(struct trace_array *tr) +static void stop_irqsoff_tracer(struct trace_array *tr, int graph) { tracer_enabled = 0; - unregister_ftrace_function(&trace_ops); + + unregister_irqsoff_function(tr, graph); } -static void __irqsoff_tracer_init(struct trace_array *tr) +static bool irqsoff_busy; + +static int __irqsoff_tracer_init(struct trace_array *tr) { - save_lat_flag = trace_flags & TRACE_ITER_LATENCY_FMT; - trace_flags |= TRACE_ITER_LATENCY_FMT; + if (irqsoff_busy) + return -EBUSY; + + save_flags = trace_flags; - tracing_max_latency = 0; + /* non overwrite screws up the latency tracers */ + set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1); + set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, 1); + + tr->max_latency = 0; irqsoff_trace = tr; /* make sure that the tracer is visible */ smp_wmb(); - start_irqsoff_tracer(tr); + tracing_reset_online_cpus(&tr->trace_buffer); + + ftrace_init_array_ops(tr, irqsoff_tracer_call); + + /* Only toplevel instance supports graph tracing */ + if (start_irqsoff_tracer(tr, (tr->flags & TRACE_ARRAY_FL_GLOBAL && + is_graph()))) + printk(KERN_ERR "failed to start irqsoff tracer\n"); + + irqsoff_busy = true; + return 0; } static void irqsoff_tracer_reset(struct trace_array *tr) { - stop_irqsoff_tracer(tr); + int lat_flag = save_flags & TRACE_ITER_LATENCY_FMT; + int overwrite_flag = save_flags & TRACE_ITER_OVERWRITE; - if (!save_lat_flag) - trace_flags &= ~TRACE_ITER_LATENCY_FMT; + stop_irqsoff_tracer(tr, is_graph()); + + set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag); + set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag); + ftrace_reset_array_ops(tr); + + irqsoff_busy = false; } static void irqsoff_tracer_start(struct trace_array *tr) @@ -405,8 +656,7 @@ static int irqsoff_tracer_init(struct trace_array *tr) { trace_type = TRACER_IRQS_OFF; - __irqsoff_tracer_init(tr); - return 0; + return __irqsoff_tracer_init(tr); } static struct tracer irqsoff_tracer __read_mostly = { @@ -415,10 +665,19 @@ static struct tracer irqsoff_tracer __read_mostly = .reset = irqsoff_tracer_reset, .start = irqsoff_tracer_start, .stop = irqsoff_tracer_stop, - .print_max = 1, + .print_max = true, + .print_header = irqsoff_print_header, + .print_line = irqsoff_print_line, + .flags = &tracer_flags, + .set_flag = irqsoff_set_flag, + .flag_changed = irqsoff_flag_changed, #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_irqsoff, #endif + .open = irqsoff_trace_open, + .close = irqsoff_trace_close, + .allow_instances = true, + .use_max_tr = true, }; # define register_irqsoff(trace) register_tracer(&trace) #else @@ -430,8 +689,7 @@ static int preemptoff_tracer_init(struct trace_array *tr) { trace_type = TRACER_PREEMPT_OFF; - __irqsoff_tracer_init(tr); - return 0; + return __irqsoff_tracer_init(tr); } static struct tracer preemptoff_tracer __read_mostly = @@ -441,10 +699,19 @@ static struct tracer preemptoff_tracer __read_mostly = .reset = irqsoff_tracer_reset, .start = irqsoff_tracer_start, .stop = irqsoff_tracer_stop, - .print_max = 1, + .print_max = true, + .print_header = irqsoff_print_header, + .print_line = irqsoff_print_line, + .flags = &tracer_flags, + .set_flag = irqsoff_set_flag, + .flag_changed = irqsoff_flag_changed, #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_preemptoff, #endif + .open = irqsoff_trace_open, + .close = irqsoff_trace_close, + .allow_instances = true, + .use_max_tr = true, }; # define register_preemptoff(trace) register_tracer(&trace) #else @@ -458,8 +725,7 @@ static int preemptirqsoff_tracer_init(struct trace_array *tr) { trace_type = TRACER_IRQS_OFF | TRACER_PREEMPT_OFF; - __irqsoff_tracer_init(tr); - return 0; + return __irqsoff_tracer_init(tr); } static struct tracer preemptirqsoff_tracer __read_mostly = @@ -469,10 +735,19 @@ static struct tracer preemptirqsoff_tracer __read_mostly = .reset = irqsoff_tracer_reset, .start = irqsoff_tracer_start, .stop = irqsoff_tracer_stop, - .print_max = 1, + .print_max = true, + .print_header = irqsoff_print_header, + .print_line = irqsoff_print_line, + .flags = &tracer_flags, + .set_flag = irqsoff_set_flag, + .flag_changed = irqsoff_flag_changed, #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_preemptirqsoff, #endif + .open = irqsoff_trace_open, + .close = irqsoff_trace_close, + .allow_instances = true, + .use_max_tr = true, }; # define register_preemptirqsoff(trace) register_tracer(&trace) @@ -488,4 +763,4 @@ __init static int init_irqsoff_tracer(void) return 0; } -device_initcall(init_irqsoff_tracer); +core_initcall(init_irqsoff_tracer); diff --git a/kernel/trace/trace_kdb.c b/kernel/trace/trace_kdb.c new file mode 100644 index 00000000000..bd90e1b0608 --- /dev/null +++ b/kernel/trace/trace_kdb.c @@ -0,0 +1,135 @@ +/* + * kdb helper for dumping the ftrace buffer + * + * Copyright (C) 2010 Jason Wessel <jason.wessel@windriver.com> + * + * ftrace_dump_buf based on ftrace_dump: + * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> + * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> + * + */ +#include <linux/init.h> +#include <linux/kgdb.h> +#include <linux/kdb.h> +#include <linux/ftrace.h> + +#include "trace.h" +#include "trace_output.h" + +static void ftrace_dump_buf(int skip_lines, long cpu_file) +{ + /* use static because iter can be a bit big for the stack */ + static struct trace_iterator iter; + unsigned int old_userobj; + int cnt = 0, cpu; + + trace_init_global_iter(&iter); + + for_each_tracing_cpu(cpu) { + atomic_inc(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); + } + + old_userobj = trace_flags; + + /* don't look at user memory in panic mode */ + trace_flags &= ~TRACE_ITER_SYM_USEROBJ; + + kdb_printf("Dumping ftrace buffer:\n"); + + /* reset all but tr, trace, and overruns */ + memset(&iter.seq, 0, + sizeof(struct trace_iterator) - + offsetof(struct trace_iterator, seq)); + iter.iter_flags |= TRACE_FILE_LAT_FMT; + iter.pos = -1; + + if (cpu_file == RING_BUFFER_ALL_CPUS) { + for_each_tracing_cpu(cpu) { + iter.buffer_iter[cpu] = + ring_buffer_read_prepare(iter.trace_buffer->buffer, cpu); + ring_buffer_read_start(iter.buffer_iter[cpu]); + tracing_iter_reset(&iter, cpu); + } + } else { + iter.cpu_file = cpu_file; + iter.buffer_iter[cpu_file] = + ring_buffer_read_prepare(iter.trace_buffer->buffer, cpu_file); + ring_buffer_read_start(iter.buffer_iter[cpu_file]); + tracing_iter_reset(&iter, cpu_file); + } + if (!trace_empty(&iter)) + trace_find_next_entry_inc(&iter); + while (!trace_empty(&iter)) { + if (!cnt) + kdb_printf("---------------------------------\n"); + cnt++; + + if (trace_find_next_entry_inc(&iter) != NULL && !skip_lines) + print_trace_line(&iter); + if (!skip_lines) + trace_printk_seq(&iter.seq); + else + skip_lines--; + if (KDB_FLAG(CMD_INTERRUPT)) + goto out; + } + + if (!cnt) + kdb_printf(" (ftrace buffer empty)\n"); + else + kdb_printf("---------------------------------\n"); + +out: + trace_flags = old_userobj; + + for_each_tracing_cpu(cpu) { + atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); + } + + for_each_tracing_cpu(cpu) + if (iter.buffer_iter[cpu]) + ring_buffer_read_finish(iter.buffer_iter[cpu]); +} + +/* + * kdb_ftdump - Dump the ftrace log buffer + */ +static int kdb_ftdump(int argc, const char **argv) +{ + int skip_lines = 0; + long cpu_file; + char *cp; + + if (argc > 2) + return KDB_ARGCOUNT; + + if (argc) { + skip_lines = simple_strtol(argv[1], &cp, 0); + if (*cp) + skip_lines = 0; + } + + if (argc == 2) { + cpu_file = simple_strtol(argv[2], &cp, 0); + if (*cp || cpu_file >= NR_CPUS || cpu_file < 0 || + !cpu_online(cpu_file)) + return KDB_BADINT; + } else { + cpu_file = RING_BUFFER_ALL_CPUS; + } + + kdb_trap_printk++; + ftrace_dump_buf(skip_lines, cpu_file); + kdb_trap_printk--; + + return 0; +} + +static __init int kdb_ftrace_register(void) +{ + kdb_register_repeat("ftdump", kdb_ftdump, "[skip_#lines] [cpu]", + "Dump ftrace log", 0, KDB_REPEAT_NONE); + return 0; +} + +late_initcall(kdb_ftrace_register); diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c new file mode 100644 index 00000000000..282f6e4e553 --- /dev/null +++ b/kernel/trace/trace_kprobe.c @@ -0,0 +1,1496 @@ +/* + * Kprobes-based tracing events + * + * Created by Masami Hiramatsu <mhiramat@redhat.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/module.h> +#include <linux/uaccess.h> + +#include "trace_probe.h" + +#define KPROBE_EVENT_SYSTEM "kprobes" + +/** + * Kprobe event core functions + */ +struct trace_kprobe { + struct list_head list; + struct kretprobe rp; /* Use rp.kp for kprobe use */ + unsigned long nhit; + const char *symbol; /* symbol name */ + struct trace_probe tp; +}; + +#define SIZEOF_TRACE_KPROBE(n) \ + (offsetof(struct trace_kprobe, tp.args) + \ + (sizeof(struct probe_arg) * (n))) + + +static nokprobe_inline bool trace_kprobe_is_return(struct trace_kprobe *tk) +{ + return tk->rp.handler != NULL; +} + +static nokprobe_inline const char *trace_kprobe_symbol(struct trace_kprobe *tk) +{ + return tk->symbol ? tk->symbol : "unknown"; +} + +static nokprobe_inline unsigned long trace_kprobe_offset(struct trace_kprobe *tk) +{ + return tk->rp.kp.offset; +} + +static nokprobe_inline bool trace_kprobe_has_gone(struct trace_kprobe *tk) +{ + return !!(kprobe_gone(&tk->rp.kp)); +} + +static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk, + struct module *mod) +{ + int len = strlen(mod->name); + const char *name = trace_kprobe_symbol(tk); + return strncmp(mod->name, name, len) == 0 && name[len] == ':'; +} + +static nokprobe_inline bool trace_kprobe_is_on_module(struct trace_kprobe *tk) +{ + return !!strchr(trace_kprobe_symbol(tk), ':'); +} + +static int register_kprobe_event(struct trace_kprobe *tk); +static int unregister_kprobe_event(struct trace_kprobe *tk); + +static DEFINE_MUTEX(probe_lock); +static LIST_HEAD(probe_list); + +static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs); +static int kretprobe_dispatcher(struct kretprobe_instance *ri, + struct pt_regs *regs); + +/* Memory fetching by symbol */ +struct symbol_cache { + char *symbol; + long offset; + unsigned long addr; +}; + +unsigned long update_symbol_cache(struct symbol_cache *sc) +{ + sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol); + + if (sc->addr) + sc->addr += sc->offset; + + return sc->addr; +} + +void free_symbol_cache(struct symbol_cache *sc) +{ + kfree(sc->symbol); + kfree(sc); +} + +struct symbol_cache *alloc_symbol_cache(const char *sym, long offset) +{ + struct symbol_cache *sc; + + if (!sym || strlen(sym) == 0) + return NULL; + + sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL); + if (!sc) + return NULL; + + sc->symbol = kstrdup(sym, GFP_KERNEL); + if (!sc->symbol) { + kfree(sc); + return NULL; + } + sc->offset = offset; + update_symbol_cache(sc); + + return sc; +} + +/* + * Kprobes-specific fetch functions + */ +#define DEFINE_FETCH_stack(type) \ +static void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs, \ + void *offset, void *dest) \ +{ \ + *(type *)dest = (type)regs_get_kernel_stack_nth(regs, \ + (unsigned int)((unsigned long)offset)); \ +} \ +NOKPROBE_SYMBOL(FETCH_FUNC_NAME(stack, type)); + +DEFINE_BASIC_FETCH_FUNCS(stack) +/* No string on the stack entry */ +#define fetch_stack_string NULL +#define fetch_stack_string_size NULL + +#define DEFINE_FETCH_memory(type) \ +static void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs, \ + void *addr, void *dest) \ +{ \ + type retval; \ + if (probe_kernel_address(addr, retval)) \ + *(type *)dest = 0; \ + else \ + *(type *)dest = retval; \ +} \ +NOKPROBE_SYMBOL(FETCH_FUNC_NAME(memory, type)); + +DEFINE_BASIC_FETCH_FUNCS(memory) +/* + * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max + * length and relative data location. + */ +static void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs, + void *addr, void *dest) +{ + long ret; + int maxlen = get_rloc_len(*(u32 *)dest); + u8 *dst = get_rloc_data(dest); + u8 *src = addr; + mm_segment_t old_fs = get_fs(); + + if (!maxlen) + return; + + /* + * Try to get string again, since the string can be changed while + * probing. + */ + set_fs(KERNEL_DS); + pagefault_disable(); + + do + ret = __copy_from_user_inatomic(dst++, src++, 1); + while (dst[-1] && ret == 0 && src - (u8 *)addr < maxlen); + + dst[-1] = '\0'; + pagefault_enable(); + set_fs(old_fs); + + if (ret < 0) { /* Failed to fetch string */ + ((u8 *)get_rloc_data(dest))[0] = '\0'; + *(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest)); + } else { + *(u32 *)dest = make_data_rloc(src - (u8 *)addr, + get_rloc_offs(*(u32 *)dest)); + } +} +NOKPROBE_SYMBOL(FETCH_FUNC_NAME(memory, string)); + +/* Return the length of string -- including null terminal byte */ +static void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs, + void *addr, void *dest) +{ + mm_segment_t old_fs; + int ret, len = 0; + u8 c; + + old_fs = get_fs(); + set_fs(KERNEL_DS); + pagefault_disable(); + + do { + ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1); + len++; + } while (c && ret == 0 && len < MAX_STRING_SIZE); + + pagefault_enable(); + set_fs(old_fs); + + if (ret < 0) /* Failed to check the length */ + *(u32 *)dest = 0; + else + *(u32 *)dest = len; +} +NOKPROBE_SYMBOL(FETCH_FUNC_NAME(memory, string_size)); + +#define DEFINE_FETCH_symbol(type) \ +void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs, void *data, void *dest)\ +{ \ + struct symbol_cache *sc = data; \ + if (sc->addr) \ + fetch_memory_##type(regs, (void *)sc->addr, dest); \ + else \ + *(type *)dest = 0; \ +} \ +NOKPROBE_SYMBOL(FETCH_FUNC_NAME(symbol, type)); + +DEFINE_BASIC_FETCH_FUNCS(symbol) +DEFINE_FETCH_symbol(string) +DEFINE_FETCH_symbol(string_size) + +/* kprobes don't support file_offset fetch methods */ +#define fetch_file_offset_u8 NULL +#define fetch_file_offset_u16 NULL +#define fetch_file_offset_u32 NULL +#define fetch_file_offset_u64 NULL +#define fetch_file_offset_string NULL +#define fetch_file_offset_string_size NULL + +/* Fetch type information table */ +const struct fetch_type kprobes_fetch_type_table[] = { + /* Special types */ + [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string, + sizeof(u32), 1, "__data_loc char[]"), + [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32, + string_size, sizeof(u32), 0, "u32"), + /* Basic types */ + ASSIGN_FETCH_TYPE(u8, u8, 0), + ASSIGN_FETCH_TYPE(u16, u16, 0), + ASSIGN_FETCH_TYPE(u32, u32, 0), + ASSIGN_FETCH_TYPE(u64, u64, 0), + ASSIGN_FETCH_TYPE(s8, u8, 1), + ASSIGN_FETCH_TYPE(s16, u16, 1), + ASSIGN_FETCH_TYPE(s32, u32, 1), + ASSIGN_FETCH_TYPE(s64, u64, 1), + + ASSIGN_FETCH_TYPE_END +}; + +/* + * Allocate new trace_probe and initialize it (including kprobes). + */ +static struct trace_kprobe *alloc_trace_kprobe(const char *group, + const char *event, + void *addr, + const char *symbol, + unsigned long offs, + int nargs, bool is_return) +{ + struct trace_kprobe *tk; + int ret = -ENOMEM; + + tk = kzalloc(SIZEOF_TRACE_KPROBE(nargs), GFP_KERNEL); + if (!tk) + return ERR_PTR(ret); + + if (symbol) { + tk->symbol = kstrdup(symbol, GFP_KERNEL); + if (!tk->symbol) + goto error; + tk->rp.kp.symbol_name = tk->symbol; + tk->rp.kp.offset = offs; + } else + tk->rp.kp.addr = addr; + + if (is_return) + tk->rp.handler = kretprobe_dispatcher; + else + tk->rp.kp.pre_handler = kprobe_dispatcher; + + if (!event || !is_good_name(event)) { + ret = -EINVAL; + goto error; + } + + tk->tp.call.class = &tk->tp.class; + tk->tp.call.name = kstrdup(event, GFP_KERNEL); + if (!tk->tp.call.name) + goto error; + + if (!group || !is_good_name(group)) { + ret = -EINVAL; + goto error; + } + + tk->tp.class.system = kstrdup(group, GFP_KERNEL); + if (!tk->tp.class.system) + goto error; + + INIT_LIST_HEAD(&tk->list); + INIT_LIST_HEAD(&tk->tp.files); + return tk; +error: + kfree(tk->tp.call.name); + kfree(tk->symbol); + kfree(tk); + return ERR_PTR(ret); +} + +static void free_trace_kprobe(struct trace_kprobe *tk) +{ + int i; + + for (i = 0; i < tk->tp.nr_args; i++) + traceprobe_free_probe_arg(&tk->tp.args[i]); + + kfree(tk->tp.call.class->system); + kfree(tk->tp.call.name); + kfree(tk->symbol); + kfree(tk); +} + +static struct trace_kprobe *find_trace_kprobe(const char *event, + const char *group) +{ + struct trace_kprobe *tk; + + list_for_each_entry(tk, &probe_list, list) + if (strcmp(ftrace_event_name(&tk->tp.call), event) == 0 && + strcmp(tk->tp.call.class->system, group) == 0) + return tk; + return NULL; +} + +/* + * Enable trace_probe + * if the file is NULL, enable "perf" handler, or enable "trace" handler. + */ +static int +enable_trace_kprobe(struct trace_kprobe *tk, struct ftrace_event_file *file) +{ + int ret = 0; + + if (file) { + struct event_file_link *link; + + link = kmalloc(sizeof(*link), GFP_KERNEL); + if (!link) { + ret = -ENOMEM; + goto out; + } + + link->file = file; + list_add_tail_rcu(&link->list, &tk->tp.files); + + tk->tp.flags |= TP_FLAG_TRACE; + } else + tk->tp.flags |= TP_FLAG_PROFILE; + + if (trace_probe_is_registered(&tk->tp) && !trace_kprobe_has_gone(tk)) { + if (trace_kprobe_is_return(tk)) + ret = enable_kretprobe(&tk->rp); + else + ret = enable_kprobe(&tk->rp.kp); + } + out: + return ret; +} + +/* + * Disable trace_probe + * if the file is NULL, disable "perf" handler, or disable "trace" handler. + */ +static int +disable_trace_kprobe(struct trace_kprobe *tk, struct ftrace_event_file *file) +{ + struct event_file_link *link = NULL; + int wait = 0; + int ret = 0; + + if (file) { + link = find_event_file_link(&tk->tp, file); + if (!link) { + ret = -EINVAL; + goto out; + } + + list_del_rcu(&link->list); + wait = 1; + if (!list_empty(&tk->tp.files)) + goto out; + + tk->tp.flags &= ~TP_FLAG_TRACE; + } else + tk->tp.flags &= ~TP_FLAG_PROFILE; + + if (!trace_probe_is_enabled(&tk->tp) && trace_probe_is_registered(&tk->tp)) { + if (trace_kprobe_is_return(tk)) + disable_kretprobe(&tk->rp); + else + disable_kprobe(&tk->rp.kp); + wait = 1; + } + out: + if (wait) { + /* + * Synchronize with kprobe_trace_func/kretprobe_trace_func + * to ensure disabled (all running handlers are finished). + * This is not only for kfree(), but also the caller, + * trace_remove_event_call() supposes it for releasing + * event_call related objects, which will be accessed in + * the kprobe_trace_func/kretprobe_trace_func. + */ + synchronize_sched(); + kfree(link); /* Ignored if link == NULL */ + } + + return ret; +} + +/* Internal register function - just handle k*probes and flags */ +static int __register_trace_kprobe(struct trace_kprobe *tk) +{ + int i, ret; + + if (trace_probe_is_registered(&tk->tp)) + return -EINVAL; + + for (i = 0; i < tk->tp.nr_args; i++) + traceprobe_update_arg(&tk->tp.args[i]); + + /* Set/clear disabled flag according to tp->flag */ + if (trace_probe_is_enabled(&tk->tp)) + tk->rp.kp.flags &= ~KPROBE_FLAG_DISABLED; + else + tk->rp.kp.flags |= KPROBE_FLAG_DISABLED; + + if (trace_kprobe_is_return(tk)) + ret = register_kretprobe(&tk->rp); + else + ret = register_kprobe(&tk->rp.kp); + + if (ret == 0) + tk->tp.flags |= TP_FLAG_REGISTERED; + else { + pr_warning("Could not insert probe at %s+%lu: %d\n", + trace_kprobe_symbol(tk), trace_kprobe_offset(tk), ret); + if (ret == -ENOENT && trace_kprobe_is_on_module(tk)) { + pr_warning("This probe might be able to register after" + "target module is loaded. Continue.\n"); + ret = 0; + } else if (ret == -EILSEQ) { + pr_warning("Probing address(0x%p) is not an " + "instruction boundary.\n", + tk->rp.kp.addr); + ret = -EINVAL; + } + } + + return ret; +} + +/* Internal unregister function - just handle k*probes and flags */ +static void __unregister_trace_kprobe(struct trace_kprobe *tk) +{ + if (trace_probe_is_registered(&tk->tp)) { + if (trace_kprobe_is_return(tk)) + unregister_kretprobe(&tk->rp); + else + unregister_kprobe(&tk->rp.kp); + tk->tp.flags &= ~TP_FLAG_REGISTERED; + /* Cleanup kprobe for reuse */ + if (tk->rp.kp.symbol_name) + tk->rp.kp.addr = NULL; + } +} + +/* Unregister a trace_probe and probe_event: call with locking probe_lock */ +static int unregister_trace_kprobe(struct trace_kprobe *tk) +{ + /* Enabled event can not be unregistered */ + if (trace_probe_is_enabled(&tk->tp)) + return -EBUSY; + + /* Will fail if probe is being used by ftrace or perf */ + if (unregister_kprobe_event(tk)) + return -EBUSY; + + __unregister_trace_kprobe(tk); + list_del(&tk->list); + + return 0; +} + +/* Register a trace_probe and probe_event */ +static int register_trace_kprobe(struct trace_kprobe *tk) +{ + struct trace_kprobe *old_tk; + int ret; + + mutex_lock(&probe_lock); + + /* Delete old (same name) event if exist */ + old_tk = find_trace_kprobe(ftrace_event_name(&tk->tp.call), + tk->tp.call.class->system); + if (old_tk) { + ret = unregister_trace_kprobe(old_tk); + if (ret < 0) + goto end; + free_trace_kprobe(old_tk); + } + + /* Register new event */ + ret = register_kprobe_event(tk); + if (ret) { + pr_warning("Failed to register probe event(%d)\n", ret); + goto end; + } + + /* Register k*probe */ + ret = __register_trace_kprobe(tk); + if (ret < 0) + unregister_kprobe_event(tk); + else + list_add_tail(&tk->list, &probe_list); + +end: + mutex_unlock(&probe_lock); + return ret; +} + +/* Module notifier call back, checking event on the module */ +static int trace_kprobe_module_callback(struct notifier_block *nb, + unsigned long val, void *data) +{ + struct module *mod = data; + struct trace_kprobe *tk; + int ret; + + if (val != MODULE_STATE_COMING) + return NOTIFY_DONE; + + /* Update probes on coming module */ + mutex_lock(&probe_lock); + list_for_each_entry(tk, &probe_list, list) { + if (trace_kprobe_within_module(tk, mod)) { + /* Don't need to check busy - this should have gone. */ + __unregister_trace_kprobe(tk); + ret = __register_trace_kprobe(tk); + if (ret) + pr_warning("Failed to re-register probe %s on" + "%s: %d\n", + ftrace_event_name(&tk->tp.call), + mod->name, ret); + } + } + mutex_unlock(&probe_lock); + + return NOTIFY_DONE; +} + +static struct notifier_block trace_kprobe_module_nb = { + .notifier_call = trace_kprobe_module_callback, + .priority = 1 /* Invoked after kprobe module callback */ +}; + +static int create_trace_kprobe(int argc, char **argv) +{ + /* + * Argument syntax: + * - Add kprobe: p[:[GRP/]EVENT] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS] + * - Add kretprobe: r[:[GRP/]EVENT] [MOD:]KSYM[+0] [FETCHARGS] + * Fetch args: + * $retval : fetch return value + * $stack : fetch stack address + * $stackN : fetch Nth of stack (N:0-) + * @ADDR : fetch memory at ADDR (ADDR should be in kernel) + * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol) + * %REG : fetch register REG + * Dereferencing memory fetch: + * +|-offs(ARG) : fetch memory at ARG +|- offs address. + * Alias name of args: + * NAME=FETCHARG : set NAME as alias of FETCHARG. + * Type of args: + * FETCHARG:TYPE : use TYPE instead of unsigned long. + */ + struct trace_kprobe *tk; + int i, ret = 0; + bool is_return = false, is_delete = false; + char *symbol = NULL, *event = NULL, *group = NULL; + char *arg; + unsigned long offset = 0; + void *addr = NULL; + char buf[MAX_EVENT_NAME_LEN]; + + /* argc must be >= 1 */ + if (argv[0][0] == 'p') + is_return = false; + else if (argv[0][0] == 'r') + is_return = true; + else if (argv[0][0] == '-') + is_delete = true; + else { + pr_info("Probe definition must be started with 'p', 'r' or" + " '-'.\n"); + return -EINVAL; + } + + if (argv[0][1] == ':') { + event = &argv[0][2]; + if (strchr(event, '/')) { + group = event; + event = strchr(group, '/') + 1; + event[-1] = '\0'; + if (strlen(group) == 0) { + pr_info("Group name is not specified\n"); + return -EINVAL; + } + } + if (strlen(event) == 0) { + pr_info("Event name is not specified\n"); + return -EINVAL; + } + } + if (!group) + group = KPROBE_EVENT_SYSTEM; + + if (is_delete) { + if (!event) { + pr_info("Delete command needs an event name.\n"); + return -EINVAL; + } + mutex_lock(&probe_lock); + tk = find_trace_kprobe(event, group); + if (!tk) { + mutex_unlock(&probe_lock); + pr_info("Event %s/%s doesn't exist.\n", group, event); + return -ENOENT; + } + /* delete an event */ + ret = unregister_trace_kprobe(tk); + if (ret == 0) + free_trace_kprobe(tk); + mutex_unlock(&probe_lock); + return ret; + } + + if (argc < 2) { + pr_info("Probe point is not specified.\n"); + return -EINVAL; + } + if (isdigit(argv[1][0])) { + if (is_return) { + pr_info("Return probe point must be a symbol.\n"); + return -EINVAL; + } + /* an address specified */ + ret = kstrtoul(&argv[1][0], 0, (unsigned long *)&addr); + if (ret) { + pr_info("Failed to parse address.\n"); + return ret; + } + } else { + /* a symbol specified */ + symbol = argv[1]; + /* TODO: support .init module functions */ + ret = traceprobe_split_symbol_offset(symbol, &offset); + if (ret) { + pr_info("Failed to parse symbol.\n"); + return ret; + } + if (offset && is_return) { + pr_info("Return probe must be used without offset.\n"); + return -EINVAL; + } + } + argc -= 2; argv += 2; + + /* setup a probe */ + if (!event) { + /* Make a new event name */ + if (symbol) + snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld", + is_return ? 'r' : 'p', symbol, offset); + else + snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p", + is_return ? 'r' : 'p', addr); + event = buf; + } + tk = alloc_trace_kprobe(group, event, addr, symbol, offset, argc, + is_return); + if (IS_ERR(tk)) { + pr_info("Failed to allocate trace_probe.(%d)\n", + (int)PTR_ERR(tk)); + return PTR_ERR(tk); + } + + /* parse arguments */ + ret = 0; + for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { + struct probe_arg *parg = &tk->tp.args[i]; + + /* Increment count for freeing args in error case */ + tk->tp.nr_args++; + + /* Parse argument name */ + arg = strchr(argv[i], '='); + if (arg) { + *arg++ = '\0'; + parg->name = kstrdup(argv[i], GFP_KERNEL); + } else { + arg = argv[i]; + /* If argument name is omitted, set "argN" */ + snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1); + parg->name = kstrdup(buf, GFP_KERNEL); + } + + if (!parg->name) { + pr_info("Failed to allocate argument[%d] name.\n", i); + ret = -ENOMEM; + goto error; + } + + if (!is_good_name(parg->name)) { + pr_info("Invalid argument[%d] name: %s\n", + i, parg->name); + ret = -EINVAL; + goto error; + } + + if (traceprobe_conflict_field_name(parg->name, + tk->tp.args, i)) { + pr_info("Argument[%d] name '%s' conflicts with " + "another field.\n", i, argv[i]); + ret = -EINVAL; + goto error; + } + + /* Parse fetch argument */ + ret = traceprobe_parse_probe_arg(arg, &tk->tp.size, parg, + is_return, true); + if (ret) { + pr_info("Parse error at argument[%d]. (%d)\n", i, ret); + goto error; + } + } + + ret = register_trace_kprobe(tk); + if (ret) + goto error; + return 0; + +error: + free_trace_kprobe(tk); + return ret; +} + +static int release_all_trace_kprobes(void) +{ + struct trace_kprobe *tk; + int ret = 0; + + mutex_lock(&probe_lock); + /* Ensure no probe is in use. */ + list_for_each_entry(tk, &probe_list, list) + if (trace_probe_is_enabled(&tk->tp)) { + ret = -EBUSY; + goto end; + } + /* TODO: Use batch unregistration */ + while (!list_empty(&probe_list)) { + tk = list_entry(probe_list.next, struct trace_kprobe, list); + ret = unregister_trace_kprobe(tk); + if (ret) + goto end; + free_trace_kprobe(tk); + } + +end: + mutex_unlock(&probe_lock); + + return ret; +} + +/* Probes listing interfaces */ +static void *probes_seq_start(struct seq_file *m, loff_t *pos) +{ + mutex_lock(&probe_lock); + return seq_list_start(&probe_list, *pos); +} + +static void *probes_seq_next(struct seq_file *m, void *v, loff_t *pos) +{ + return seq_list_next(v, &probe_list, pos); +} + +static void probes_seq_stop(struct seq_file *m, void *v) +{ + mutex_unlock(&probe_lock); +} + +static int probes_seq_show(struct seq_file *m, void *v) +{ + struct trace_kprobe *tk = v; + int i; + + seq_printf(m, "%c", trace_kprobe_is_return(tk) ? 'r' : 'p'); + seq_printf(m, ":%s/%s", tk->tp.call.class->system, + ftrace_event_name(&tk->tp.call)); + + if (!tk->symbol) + seq_printf(m, " 0x%p", tk->rp.kp.addr); + else if (tk->rp.kp.offset) + seq_printf(m, " %s+%u", trace_kprobe_symbol(tk), + tk->rp.kp.offset); + else + seq_printf(m, " %s", trace_kprobe_symbol(tk)); + + for (i = 0; i < tk->tp.nr_args; i++) + seq_printf(m, " %s=%s", tk->tp.args[i].name, tk->tp.args[i].comm); + seq_printf(m, "\n"); + + return 0; +} + +static const struct seq_operations probes_seq_op = { + .start = probes_seq_start, + .next = probes_seq_next, + .stop = probes_seq_stop, + .show = probes_seq_show +}; + +static int probes_open(struct inode *inode, struct file *file) +{ + int ret; + + if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { + ret = release_all_trace_kprobes(); + if (ret < 0) + return ret; + } + + return seq_open(file, &probes_seq_op); +} + +static ssize_t probes_write(struct file *file, const char __user *buffer, + size_t count, loff_t *ppos) +{ + return traceprobe_probes_write(file, buffer, count, ppos, + create_trace_kprobe); +} + +static const struct file_operations kprobe_events_ops = { + .owner = THIS_MODULE, + .open = probes_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, + .write = probes_write, +}; + +/* Probes profiling interfaces */ +static int probes_profile_seq_show(struct seq_file *m, void *v) +{ + struct trace_kprobe *tk = v; + + seq_printf(m, " %-44s %15lu %15lu\n", + ftrace_event_name(&tk->tp.call), tk->nhit, + tk->rp.kp.nmissed); + + return 0; +} + +static const struct seq_operations profile_seq_op = { + .start = probes_seq_start, + .next = probes_seq_next, + .stop = probes_seq_stop, + .show = probes_profile_seq_show +}; + +static int profile_open(struct inode *inode, struct file *file) +{ + return seq_open(file, &profile_seq_op); +} + +static const struct file_operations kprobe_profile_ops = { + .owner = THIS_MODULE, + .open = profile_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +/* Kprobe handler */ +static nokprobe_inline void +__kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs, + struct ftrace_event_file *ftrace_file) +{ + struct kprobe_trace_entry_head *entry; + struct ring_buffer_event *event; + struct ring_buffer *buffer; + int size, dsize, pc; + unsigned long irq_flags; + struct ftrace_event_call *call = &tk->tp.call; + + WARN_ON(call != ftrace_file->event_call); + + if (ftrace_trigger_soft_disabled(ftrace_file)) + return; + + local_save_flags(irq_flags); + pc = preempt_count(); + + dsize = __get_data_size(&tk->tp, regs); + size = sizeof(*entry) + tk->tp.size + dsize; + + event = trace_event_buffer_lock_reserve(&buffer, ftrace_file, + call->event.type, + size, irq_flags, pc); + if (!event) + return; + + entry = ring_buffer_event_data(event); + entry->ip = (unsigned long)tk->rp.kp.addr; + store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); + + event_trigger_unlock_commit_regs(ftrace_file, buffer, event, + entry, irq_flags, pc, regs); +} + +static void +kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs) +{ + struct event_file_link *link; + + list_for_each_entry_rcu(link, &tk->tp.files, list) + __kprobe_trace_func(tk, regs, link->file); +} +NOKPROBE_SYMBOL(kprobe_trace_func); + +/* Kretprobe handler */ +static nokprobe_inline void +__kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, + struct pt_regs *regs, + struct ftrace_event_file *ftrace_file) +{ + struct kretprobe_trace_entry_head *entry; + struct ring_buffer_event *event; + struct ring_buffer *buffer; + int size, pc, dsize; + unsigned long irq_flags; + struct ftrace_event_call *call = &tk->tp.call; + + WARN_ON(call != ftrace_file->event_call); + + if (ftrace_trigger_soft_disabled(ftrace_file)) + return; + + local_save_flags(irq_flags); + pc = preempt_count(); + + dsize = __get_data_size(&tk->tp, regs); + size = sizeof(*entry) + tk->tp.size + dsize; + + event = trace_event_buffer_lock_reserve(&buffer, ftrace_file, + call->event.type, + size, irq_flags, pc); + if (!event) + return; + + entry = ring_buffer_event_data(event); + entry->func = (unsigned long)tk->rp.kp.addr; + entry->ret_ip = (unsigned long)ri->ret_addr; + store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); + + event_trigger_unlock_commit_regs(ftrace_file, buffer, event, + entry, irq_flags, pc, regs); +} + +static void +kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, + struct pt_regs *regs) +{ + struct event_file_link *link; + + list_for_each_entry_rcu(link, &tk->tp.files, list) + __kretprobe_trace_func(tk, ri, regs, link->file); +} +NOKPROBE_SYMBOL(kretprobe_trace_func); + +/* Event entry printers */ +static enum print_line_t +print_kprobe_event(struct trace_iterator *iter, int flags, + struct trace_event *event) +{ + struct kprobe_trace_entry_head *field; + struct trace_seq *s = &iter->seq; + struct trace_probe *tp; + u8 *data; + int i; + + field = (struct kprobe_trace_entry_head *)iter->ent; + tp = container_of(event, struct trace_probe, call.event); + + if (!trace_seq_printf(s, "%s: (", ftrace_event_name(&tp->call))) + goto partial; + + if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET)) + goto partial; + + if (!trace_seq_puts(s, ")")) + goto partial; + + data = (u8 *)&field[1]; + for (i = 0; i < tp->nr_args; i++) + if (!tp->args[i].type->print(s, tp->args[i].name, + data + tp->args[i].offset, field)) + goto partial; + + if (!trace_seq_puts(s, "\n")) + goto partial; + + return TRACE_TYPE_HANDLED; +partial: + return TRACE_TYPE_PARTIAL_LINE; +} + +static enum print_line_t +print_kretprobe_event(struct trace_iterator *iter, int flags, + struct trace_event *event) +{ + struct kretprobe_trace_entry_head *field; + struct trace_seq *s = &iter->seq; + struct trace_probe *tp; + u8 *data; + int i; + + field = (struct kretprobe_trace_entry_head *)iter->ent; + tp = container_of(event, struct trace_probe, call.event); + + if (!trace_seq_printf(s, "%s: (", ftrace_event_name(&tp->call))) + goto partial; + + if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET)) + goto partial; + + if (!trace_seq_puts(s, " <- ")) + goto partial; + + if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET)) + goto partial; + + if (!trace_seq_puts(s, ")")) + goto partial; + + data = (u8 *)&field[1]; + for (i = 0; i < tp->nr_args; i++) + if (!tp->args[i].type->print(s, tp->args[i].name, + data + tp->args[i].offset, field)) + goto partial; + + if (!trace_seq_puts(s, "\n")) + goto partial; + + return TRACE_TYPE_HANDLED; +partial: + return TRACE_TYPE_PARTIAL_LINE; +} + + +static int kprobe_event_define_fields(struct ftrace_event_call *event_call) +{ + int ret, i; + struct kprobe_trace_entry_head field; + struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data; + + DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0); + /* Set argument names as fields */ + for (i = 0; i < tk->tp.nr_args; i++) { + struct probe_arg *parg = &tk->tp.args[i]; + + ret = trace_define_field(event_call, parg->type->fmttype, + parg->name, + sizeof(field) + parg->offset, + parg->type->size, + parg->type->is_signed, + FILTER_OTHER); + if (ret) + return ret; + } + return 0; +} + +static int kretprobe_event_define_fields(struct ftrace_event_call *event_call) +{ + int ret, i; + struct kretprobe_trace_entry_head field; + struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data; + + DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0); + DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0); + /* Set argument names as fields */ + for (i = 0; i < tk->tp.nr_args; i++) { + struct probe_arg *parg = &tk->tp.args[i]; + + ret = trace_define_field(event_call, parg->type->fmttype, + parg->name, + sizeof(field) + parg->offset, + parg->type->size, + parg->type->is_signed, + FILTER_OTHER); + if (ret) + return ret; + } + return 0; +} + +#ifdef CONFIG_PERF_EVENTS + +/* Kprobe profile handler */ +static void +kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs) +{ + struct ftrace_event_call *call = &tk->tp.call; + struct kprobe_trace_entry_head *entry; + struct hlist_head *head; + int size, __size, dsize; + int rctx; + + head = this_cpu_ptr(call->perf_events); + if (hlist_empty(head)) + return; + + dsize = __get_data_size(&tk->tp, regs); + __size = sizeof(*entry) + tk->tp.size + dsize; + size = ALIGN(__size + sizeof(u32), sizeof(u64)); + size -= sizeof(u32); + + entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx); + if (!entry) + return; + + entry->ip = (unsigned long)tk->rp.kp.addr; + memset(&entry[1], 0, dsize); + store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); + perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL); +} +NOKPROBE_SYMBOL(kprobe_perf_func); + +/* Kretprobe profile handler */ +static void +kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, + struct pt_regs *regs) +{ + struct ftrace_event_call *call = &tk->tp.call; + struct kretprobe_trace_entry_head *entry; + struct hlist_head *head; + int size, __size, dsize; + int rctx; + + head = this_cpu_ptr(call->perf_events); + if (hlist_empty(head)) + return; + + dsize = __get_data_size(&tk->tp, regs); + __size = sizeof(*entry) + tk->tp.size + dsize; + size = ALIGN(__size + sizeof(u32), sizeof(u64)); + size -= sizeof(u32); + + entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx); + if (!entry) + return; + + entry->func = (unsigned long)tk->rp.kp.addr; + entry->ret_ip = (unsigned long)ri->ret_addr; + store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); + perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL); +} +NOKPROBE_SYMBOL(kretprobe_perf_func); +#endif /* CONFIG_PERF_EVENTS */ + +/* + * called by perf_trace_init() or __ftrace_set_clr_event() under event_mutex. + * + * kprobe_trace_self_tests_init() does enable_trace_probe/disable_trace_probe + * lockless, but we can't race with this __init function. + */ +static int kprobe_register(struct ftrace_event_call *event, + enum trace_reg type, void *data) +{ + struct trace_kprobe *tk = (struct trace_kprobe *)event->data; + struct ftrace_event_file *file = data; + + switch (type) { + case TRACE_REG_REGISTER: + return enable_trace_kprobe(tk, file); + case TRACE_REG_UNREGISTER: + return disable_trace_kprobe(tk, file); + +#ifdef CONFIG_PERF_EVENTS + case TRACE_REG_PERF_REGISTER: + return enable_trace_kprobe(tk, NULL); + case TRACE_REG_PERF_UNREGISTER: + return disable_trace_kprobe(tk, NULL); + case TRACE_REG_PERF_OPEN: + case TRACE_REG_PERF_CLOSE: + case TRACE_REG_PERF_ADD: + case TRACE_REG_PERF_DEL: + return 0; +#endif + } + return 0; +} + +static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) +{ + struct trace_kprobe *tk = container_of(kp, struct trace_kprobe, rp.kp); + + tk->nhit++; + + if (tk->tp.flags & TP_FLAG_TRACE) + kprobe_trace_func(tk, regs); +#ifdef CONFIG_PERF_EVENTS + if (tk->tp.flags & TP_FLAG_PROFILE) + kprobe_perf_func(tk, regs); +#endif + return 0; /* We don't tweek kernel, so just return 0 */ +} +NOKPROBE_SYMBOL(kprobe_dispatcher); + +static int +kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs) +{ + struct trace_kprobe *tk = container_of(ri->rp, struct trace_kprobe, rp); + + tk->nhit++; + + if (tk->tp.flags & TP_FLAG_TRACE) + kretprobe_trace_func(tk, ri, regs); +#ifdef CONFIG_PERF_EVENTS + if (tk->tp.flags & TP_FLAG_PROFILE) + kretprobe_perf_func(tk, ri, regs); +#endif + return 0; /* We don't tweek kernel, so just return 0 */ +} +NOKPROBE_SYMBOL(kretprobe_dispatcher); + +static struct trace_event_functions kretprobe_funcs = { + .trace = print_kretprobe_event +}; + +static struct trace_event_functions kprobe_funcs = { + .trace = print_kprobe_event +}; + +static int register_kprobe_event(struct trace_kprobe *tk) +{ + struct ftrace_event_call *call = &tk->tp.call; + int ret; + + /* Initialize ftrace_event_call */ + INIT_LIST_HEAD(&call->class->fields); + if (trace_kprobe_is_return(tk)) { + call->event.funcs = &kretprobe_funcs; + call->class->define_fields = kretprobe_event_define_fields; + } else { + call->event.funcs = &kprobe_funcs; + call->class->define_fields = kprobe_event_define_fields; + } + if (set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0) + return -ENOMEM; + ret = register_ftrace_event(&call->event); + if (!ret) { + kfree(call->print_fmt); + return -ENODEV; + } + call->flags = 0; + call->class->reg = kprobe_register; + call->data = tk; + ret = trace_add_event_call(call); + if (ret) { + pr_info("Failed to register kprobe event: %s\n", + ftrace_event_name(call)); + kfree(call->print_fmt); + unregister_ftrace_event(&call->event); + } + return ret; +} + +static int unregister_kprobe_event(struct trace_kprobe *tk) +{ + int ret; + + /* tp->event is unregistered in trace_remove_event_call() */ + ret = trace_remove_event_call(&tk->tp.call); + if (!ret) + kfree(tk->tp.call.print_fmt); + return ret; +} + +/* Make a debugfs interface for controlling probe points */ +static __init int init_kprobe_trace(void) +{ + struct dentry *d_tracer; + struct dentry *entry; + + if (register_module_notifier(&trace_kprobe_module_nb)) + return -EINVAL; + + d_tracer = tracing_init_dentry(); + if (!d_tracer) + return 0; + + entry = debugfs_create_file("kprobe_events", 0644, d_tracer, + NULL, &kprobe_events_ops); + + /* Event list interface */ + if (!entry) + pr_warning("Could not create debugfs " + "'kprobe_events' entry\n"); + + /* Profile interface */ + entry = debugfs_create_file("kprobe_profile", 0444, d_tracer, + NULL, &kprobe_profile_ops); + + if (!entry) + pr_warning("Could not create debugfs " + "'kprobe_profile' entry\n"); + return 0; +} +fs_initcall(init_kprobe_trace); + + +#ifdef CONFIG_FTRACE_STARTUP_TEST + +/* + * The "__used" keeps gcc from removing the function symbol + * from the kallsyms table. + */ +static __used int kprobe_trace_selftest_target(int a1, int a2, int a3, + int a4, int a5, int a6) +{ + return a1 + a2 + a3 + a4 + a5 + a6; +} + +static struct ftrace_event_file * +find_trace_probe_file(struct trace_kprobe *tk, struct trace_array *tr) +{ + struct ftrace_event_file *file; + + list_for_each_entry(file, &tr->events, list) + if (file->event_call == &tk->tp.call) + return file; + + return NULL; +} + +/* + * Nobody but us can call enable_trace_kprobe/disable_trace_kprobe at this + * stage, we can do this lockless. + */ +static __init int kprobe_trace_self_tests_init(void) +{ + int ret, warn = 0; + int (*target)(int, int, int, int, int, int); + struct trace_kprobe *tk; + struct ftrace_event_file *file; + + if (tracing_is_disabled()) + return -ENODEV; + + target = kprobe_trace_selftest_target; + + pr_info("Testing kprobe tracing: "); + + ret = traceprobe_command("p:testprobe kprobe_trace_selftest_target " + "$stack $stack0 +0($stack)", + create_trace_kprobe); + if (WARN_ON_ONCE(ret)) { + pr_warn("error on probing function entry.\n"); + warn++; + } else { + /* Enable trace point */ + tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); + if (WARN_ON_ONCE(tk == NULL)) { + pr_warn("error on getting new probe.\n"); + warn++; + } else { + file = find_trace_probe_file(tk, top_trace_array()); + if (WARN_ON_ONCE(file == NULL)) { + pr_warn("error on getting probe file.\n"); + warn++; + } else + enable_trace_kprobe(tk, file); + } + } + + ret = traceprobe_command("r:testprobe2 kprobe_trace_selftest_target " + "$retval", create_trace_kprobe); + if (WARN_ON_ONCE(ret)) { + pr_warn("error on probing function return.\n"); + warn++; + } else { + /* Enable trace point */ + tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); + if (WARN_ON_ONCE(tk == NULL)) { + pr_warn("error on getting 2nd new probe.\n"); + warn++; + } else { + file = find_trace_probe_file(tk, top_trace_array()); + if (WARN_ON_ONCE(file == NULL)) { + pr_warn("error on getting probe file.\n"); + warn++; + } else + enable_trace_kprobe(tk, file); + } + } + + if (warn) + goto end; + + ret = target(1, 2, 3, 4, 5, 6); + + /* Disable trace points before removing it */ + tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); + if (WARN_ON_ONCE(tk == NULL)) { + pr_warn("error on getting test probe.\n"); + warn++; + } else { + file = find_trace_probe_file(tk, top_trace_array()); + if (WARN_ON_ONCE(file == NULL)) { + pr_warn("error on getting probe file.\n"); + warn++; + } else + disable_trace_kprobe(tk, file); + } + + tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); + if (WARN_ON_ONCE(tk == NULL)) { + pr_warn("error on getting 2nd test probe.\n"); + warn++; + } else { + file = find_trace_probe_file(tk, top_trace_array()); + if (WARN_ON_ONCE(file == NULL)) { + pr_warn("error on getting probe file.\n"); + warn++; + } else + disable_trace_kprobe(tk, file); + } + + ret = traceprobe_command("-:testprobe", create_trace_kprobe); + if (WARN_ON_ONCE(ret)) { + pr_warn("error on deleting a probe.\n"); + warn++; + } + + ret = traceprobe_command("-:testprobe2", create_trace_kprobe); + if (WARN_ON_ONCE(ret)) { + pr_warn("error on deleting a probe.\n"); + warn++; + } + +end: + release_all_trace_kprobes(); + if (warn) + pr_cont("NG: Some tests are failed. Please check them.\n"); + else + pr_cont("OK\n"); + return 0; +} + +late_initcall(kprobe_trace_self_tests_init); + +#endif diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c index d53b45ed080..0abd9b86347 100644 --- a/kernel/trace/trace_mmiotrace.c +++ b/kernel/trace/trace_mmiotrace.c @@ -9,9 +9,10 @@ #include <linux/kernel.h> #include <linux/mmiotrace.h> #include <linux/pci.h> +#include <linux/slab.h> #include <linux/time.h> -#include <asm/atomic.h> +#include <linux/atomic.h> #include "trace.h" #include "trace_output.h" @@ -30,7 +31,7 @@ static void mmio_reset_data(struct trace_array *tr) overrun_detected = false; prev_overruns = 0; - tracing_reset_online_cpus(tr); + tracing_reset_online_cpus(&tr->trace_buffer); } static int mmio_trace_init(struct trace_array *tr) @@ -89,7 +90,7 @@ static int mmio_print_pcidev(struct trace_seq *s, const struct pci_dev *dev) if (drv) ret += trace_seq_printf(s, " %s\n", drv->name); else - ret += trace_seq_printf(s, " \n"); + ret += trace_seq_puts(s, " \n"); return ret; } @@ -106,7 +107,7 @@ static void mmio_pipe_open(struct trace_iterator *iter) struct header_iter *hiter; struct trace_seq *s = &iter->seq; - trace_seq_printf(s, "VERSION 20070824\n"); + trace_seq_puts(s, "VERSION 20070824\n"); hiter = kzalloc(sizeof(*hiter), GFP_KERNEL); if (!hiter) @@ -127,7 +128,7 @@ static void mmio_close(struct trace_iterator *iter) static unsigned long count_overruns(struct trace_iterator *iter) { unsigned long cnt = atomic_xchg(&dropped_count, 0); - unsigned long over = ring_buffer_overruns(iter->tr->buffer); + unsigned long over = ring_buffer_overruns(iter->trace_buffer->buffer); if (over > prev_overruns) cnt += over - prev_overruns; @@ -208,7 +209,7 @@ static enum print_line_t mmio_print_rw(struct trace_iterator *iter) (rw->value >> 0) & 0xff, rw->pc, 0); break; default: - ret = trace_seq_printf(s, "rw what?\n"); + ret = trace_seq_puts(s, "rw what?\n"); break; } if (ret) @@ -244,7 +245,7 @@ static enum print_line_t mmio_print_map(struct trace_iterator *iter) secs, usec_rem, m->map_id, 0UL, 0); break; default: - ret = trace_seq_printf(s, "map what?\n"); + ret = trace_seq_puts(s, "map what?\n"); break; } if (ret) @@ -307,11 +308,13 @@ static void __trace_mmiotrace_rw(struct trace_array *tr, struct trace_array_cpu *data, struct mmiotrace_rw *rw) { + struct ftrace_event_call *call = &event_mmiotrace_rw; + struct ring_buffer *buffer = tr->trace_buffer.buffer; struct ring_buffer_event *event; struct trace_mmiotrace_rw *entry; int pc = preempt_count(); - event = trace_buffer_lock_reserve(tr, TRACE_MMIO_RW, + event = trace_buffer_lock_reserve(buffer, TRACE_MMIO_RW, sizeof(*entry), 0, pc); if (!event) { atomic_inc(&dropped_count); @@ -319,13 +322,15 @@ static void __trace_mmiotrace_rw(struct trace_array *tr, } entry = ring_buffer_event_data(event); entry->rw = *rw; - trace_buffer_unlock_commit(tr, event, 0, pc); + + if (!call_filter_check_discard(call, entry, buffer, event)) + trace_buffer_unlock_commit(buffer, event, 0, pc); } void mmio_trace_rw(struct mmiotrace_rw *rw) { struct trace_array *tr = mmio_trace_array; - struct trace_array_cpu *data = tr->data[smp_processor_id()]; + struct trace_array_cpu *data = per_cpu_ptr(tr->trace_buffer.data, smp_processor_id()); __trace_mmiotrace_rw(tr, data, rw); } @@ -333,11 +338,13 @@ static void __trace_mmiotrace_map(struct trace_array *tr, struct trace_array_cpu *data, struct mmiotrace_map *map) { + struct ftrace_event_call *call = &event_mmiotrace_map; + struct ring_buffer *buffer = tr->trace_buffer.buffer; struct ring_buffer_event *event; struct trace_mmiotrace_map *entry; int pc = preempt_count(); - event = trace_buffer_lock_reserve(tr, TRACE_MMIO_MAP, + event = trace_buffer_lock_reserve(buffer, TRACE_MMIO_MAP, sizeof(*entry), 0, pc); if (!event) { atomic_inc(&dropped_count); @@ -345,7 +352,9 @@ static void __trace_mmiotrace_map(struct trace_array *tr, } entry = ring_buffer_event_data(event); entry->map = *map; - trace_buffer_unlock_commit(tr, event, 0, pc); + + if (!call_filter_check_discard(call, entry, buffer, event)) + trace_buffer_unlock_commit(buffer, event, 0, pc); } void mmio_trace_mapping(struct mmiotrace_map *map) @@ -354,7 +363,7 @@ void mmio_trace_mapping(struct mmiotrace_map *map) struct trace_array_cpu *data; preempt_disable(); - data = tr->data[smp_processor_id()]; + data = per_cpu_ptr(tr->trace_buffer.data, smp_processor_id()); __trace_mmiotrace_map(tr, data, map); preempt_enable(); } diff --git a/kernel/trace/trace_nop.c b/kernel/trace/trace_nop.c index 394f94417e2..fcf0a9e4891 100644 --- a/kernel/trace/trace_nop.c +++ b/kernel/trace/trace_nop.c @@ -62,7 +62,7 @@ static void nop_trace_reset(struct trace_array *tr) * If you don't implement it, then the flag setting will be * automatically accepted. */ -static int nop_set_flag(u32 old_flags, u32 bit, int set) +static int nop_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) { /* * Note that you don't need to update nop_flags.val yourself. @@ -91,11 +91,11 @@ struct tracer nop_trace __read_mostly = .name = "nop", .init = nop_trace_init, .reset = nop_trace_reset, - .wait_pipe = poll_wait_pipe, #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_nop, #endif .flags = &nop_flags, - .set_flag = nop_set_flag + .set_flag = nop_set_flag, + .allow_instances = true, }; diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index 7938f3ae93e..f3dad80c20b 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -14,23 +14,43 @@ /* must be a power of 2 */ #define EVENT_HASHSIZE 128 -DECLARE_RWSEM(trace_event_mutex); - -DEFINE_PER_CPU(struct trace_seq, ftrace_event_seq); -EXPORT_PER_CPU_SYMBOL(ftrace_event_seq); +DECLARE_RWSEM(trace_event_sem); static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly; static int next_event_type = __TRACE_LAST_TYPE + 1; -void trace_print_seq(struct seq_file *m, struct trace_seq *s) +int trace_print_seq(struct seq_file *m, struct trace_seq *s) { int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; + int ret; + + ret = seq_write(m, s->buffer, len); + + /* + * Only reset this buffer if we successfully wrote to the + * seq_file buffer. + */ + if (!ret) + trace_seq_init(s); + + return ret; +} - s->buffer[len] = 0; - seq_puts(m, s->buffer); +enum print_line_t trace_print_bputs_msg_only(struct trace_iterator *iter) +{ + struct trace_seq *s = &iter->seq; + struct trace_entry *entry = iter->ent; + struct bputs_entry *field; + int ret; + + trace_assign_type(field, entry); + + ret = trace_seq_puts(s, field->str); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; - trace_seq_init(s); + return TRACE_TYPE_HANDLED; } enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter) @@ -58,7 +78,7 @@ enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter) trace_assign_type(field, entry); - ret = trace_seq_printf(s, "%s", field->buf); + ret = trace_seq_puts(s, field->buf); if (!ret) return TRACE_TYPE_PARTIAL_LINE; @@ -70,6 +90,9 @@ enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter) * @s: trace sequence descriptor * @fmt: printf format string * + * It returns 0 if the trace oversizes the buffer's free + * space, 1 otherwise. + * * The tracer may use either sequence operations or its own * copy to user routines. To simplify formating of a trace * trace_seq_printf is used to store strings into a special @@ -83,7 +106,7 @@ trace_seq_printf(struct trace_seq *s, const char *fmt, ...) va_list ap; int ret; - if (!len) + if (s->full || !len) return 0; va_start(ap, fmt); @@ -91,16 +114,46 @@ trace_seq_printf(struct trace_seq *s, const char *fmt, ...) va_end(ap); /* If we can't write it all, don't bother writing anything */ - if (ret >= len) + if (ret >= len) { + s->full = 1; return 0; + } s->len += ret; - return len; + return 1; } EXPORT_SYMBOL_GPL(trace_seq_printf); /** + * trace_seq_bitmask - put a list of longs as a bitmask print output + * @s: trace sequence descriptor + * @maskp: points to an array of unsigned longs that represent a bitmask + * @nmaskbits: The number of bits that are valid in @maskp + * + * It returns 0 if the trace oversizes the buffer's free + * space, 1 otherwise. + * + * Writes a ASCII representation of a bitmask string into @s. + */ +int +trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp, + int nmaskbits) +{ + int len = (PAGE_SIZE - 1) - s->len; + int ret; + + if (s->full || !len) + return 0; + + ret = bitmap_scnprintf(s->buffer, len, maskp, nmaskbits); + s->len += ret; + + return 1; +} +EXPORT_SYMBOL_GPL(trace_seq_bitmask); + +/** * trace_seq_vprintf - sequence printing of trace information * @s: trace sequence descriptor * @fmt: printf format string @@ -117,14 +170,16 @@ trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args) int len = (PAGE_SIZE - 1) - s->len; int ret; - if (!len) + if (s->full || !len) return 0; ret = vsnprintf(s->buffer + s->len, len, fmt, args); /* If we can't write it all, don't bother writing anything */ - if (ret >= len) + if (ret >= len) { + s->full = 1; return 0; + } s->len += ret; @@ -137,14 +192,16 @@ int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary) int len = (PAGE_SIZE - 1) - s->len; int ret; - if (!len) + if (s->full || !len) return 0; ret = bstr_printf(s->buffer + s->len, len, fmt, binary); /* If we can't write it all, don't bother writing anything */ - if (ret >= len) + if (ret >= len) { + s->full = 1; return 0; + } s->len += ret; @@ -165,8 +222,13 @@ int trace_seq_puts(struct trace_seq *s, const char *str) { int len = strlen(str); - if (len > ((PAGE_SIZE - 1) - s->len)) + if (s->full) + return 0; + + if (len > ((PAGE_SIZE - 1) - s->len)) { + s->full = 1; return 0; + } memcpy(s->buffer + s->len, str, len); s->len += len; @@ -176,19 +238,30 @@ int trace_seq_puts(struct trace_seq *s, const char *str) int trace_seq_putc(struct trace_seq *s, unsigned char c) { - if (s->len >= (PAGE_SIZE - 1)) + if (s->full) return 0; + if (s->len >= (PAGE_SIZE - 1)) { + s->full = 1; + return 0; + } + s->buffer[s->len++] = c; return 1; } +EXPORT_SYMBOL(trace_seq_putc); int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len) { - if (len > ((PAGE_SIZE - 1) - s->len)) + if (s->full) return 0; + if (len > ((PAGE_SIZE - 1) - s->len)) { + s->full = 1; + return 0; + } + memcpy(s->buffer + s->len, mem, len); s->len += len; @@ -201,6 +274,9 @@ int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len) const unsigned char *data = mem; int i, j; + if (s->full) + return 0; + #ifdef __BIG_ENDIAN for (i = 0, j = 0; i < len; i++) { #else @@ -218,21 +294,32 @@ void *trace_seq_reserve(struct trace_seq *s, size_t len) { void *ret; - if (len > ((PAGE_SIZE - 1) - s->len)) + if (s->full) return NULL; + if (len > ((PAGE_SIZE - 1) - s->len)) { + s->full = 1; + return NULL; + } + ret = s->buffer + s->len; s->len += len; return ret; } -int trace_seq_path(struct trace_seq *s, struct path *path) +int trace_seq_path(struct trace_seq *s, const struct path *path) { unsigned char *p; - if (s->len >= (PAGE_SIZE - 1)) + if (s->full) return 0; + + if (s->len >= (PAGE_SIZE - 1)) { + s->full = 1; + return 0; + } + p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len); if (!IS_ERR(p)) { p = mangle_path(s->buffer + s->len, p, "\n"); @@ -245,6 +332,7 @@ int trace_seq_path(struct trace_seq *s, struct path *path) return 1; } + s->full = 1; return 0; } @@ -256,7 +344,7 @@ ftrace_print_flags_seq(struct trace_seq *p, const char *delim, unsigned long mask; const char *str; const char *ret = p->buffer + p->len; - int i; + int i, first = 1; for (i = 0; flag_array[i].name && flags; i++) { @@ -266,14 +354,16 @@ ftrace_print_flags_seq(struct trace_seq *p, const char *delim, str = flag_array[i].name; flags &= ~mask; - if (p->len && delim) + if (!first && delim) trace_seq_puts(p, delim); + else + first = 0; trace_seq_puts(p, str); } /* check for left over flags */ if (flags) { - if (p->len && delim) + if (!first && delim) trace_seq_puts(p, delim); trace_seq_printf(p, "0x%lx", flags); } @@ -300,7 +390,7 @@ ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val, break; } - if (!p->len) + if (ret == (const char *)(p->buffer + p->len)) trace_seq_printf(p, "0x%lx", val); trace_seq_putc(p, 0); @@ -309,6 +399,118 @@ ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val, } EXPORT_SYMBOL(ftrace_print_symbols_seq); +#if BITS_PER_LONG == 32 +const char * +ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val, + const struct trace_print_flags_u64 *symbol_array) +{ + int i; + const char *ret = p->buffer + p->len; + + for (i = 0; symbol_array[i].name; i++) { + + if (val != symbol_array[i].mask) + continue; + + trace_seq_puts(p, symbol_array[i].name); + break; + } + + if (ret == (const char *)(p->buffer + p->len)) + trace_seq_printf(p, "0x%llx", val); + + trace_seq_putc(p, 0); + + return ret; +} +EXPORT_SYMBOL(ftrace_print_symbols_seq_u64); +#endif + +const char * +ftrace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr, + unsigned int bitmask_size) +{ + const char *ret = p->buffer + p->len; + + trace_seq_bitmask(p, bitmask_ptr, bitmask_size * 8); + trace_seq_putc(p, 0); + + return ret; +} +EXPORT_SYMBOL_GPL(ftrace_print_bitmask_seq); + +const char * +ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len) +{ + int i; + const char *ret = p->buffer + p->len; + + for (i = 0; i < buf_len; i++) + trace_seq_printf(p, "%s%2.2x", i == 0 ? "" : " ", buf[i]); + + trace_seq_putc(p, 0); + + return ret; +} +EXPORT_SYMBOL(ftrace_print_hex_seq); + +int ftrace_raw_output_prep(struct trace_iterator *iter, + struct trace_event *trace_event) +{ + struct ftrace_event_call *event; + struct trace_seq *s = &iter->seq; + struct trace_seq *p = &iter->tmp_seq; + struct trace_entry *entry; + int ret; + + event = container_of(trace_event, struct ftrace_event_call, event); + entry = iter->ent; + + if (entry->type != event->event.type) { + WARN_ON_ONCE(1); + return TRACE_TYPE_UNHANDLED; + } + + trace_seq_init(p); + ret = trace_seq_printf(s, "%s: ", ftrace_event_name(event)); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + + return 0; +} +EXPORT_SYMBOL(ftrace_raw_output_prep); + +static int ftrace_output_raw(struct trace_iterator *iter, char *name, + char *fmt, va_list ap) +{ + struct trace_seq *s = &iter->seq; + int ret; + + ret = trace_seq_printf(s, "%s: ", name); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + + ret = trace_seq_vprintf(s, fmt, ap); + + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + + return TRACE_TYPE_HANDLED; +} + +int ftrace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...) +{ + va_list ap; + int ret; + + va_start(ap, fmt); + ret = ftrace_output_raw(iter, name, fmt, ap); + va_end(ap); + + return ret; +} +EXPORT_SYMBOL_GPL(ftrace_output_call); + #ifdef CONFIG_KRETPROBES static inline const char *kretprobed(const char *name) { @@ -371,6 +573,9 @@ int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm, unsigned long vmstart = 0; int ret = 1; + if (s->full) + return 0; + if (mm) { const struct vm_area_struct *vma; @@ -408,7 +613,7 @@ seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s, * since individual threads might have already quit! */ rcu_read_lock(); - task = find_task_by_vpid(entry->ent.tgid); + task = find_task_by_vpid(entry->tgid); if (task) mm = get_task_mm(task); rcu_read_unlock(); @@ -425,14 +630,14 @@ seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s, if (ret) ret = trace_seq_puts(s, "??"); if (ret) - ret = trace_seq_puts(s, "\n"); + ret = trace_seq_putc(s, '\n'); continue; } if (!ret) break; if (ret) ret = seq_print_user_ip(s, mm, ip, sym_flags); - ret = trace_seq_puts(s, "\n"); + ret = trace_seq_putc(s, '\n'); } if (mm) @@ -446,7 +651,7 @@ seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags) int ret; if (!ip) - return trace_seq_printf(s, "0"); + return trace_seq_putc(s, '0'); if (sym_flags & TRACE_ITER_SYM_OFFSET) ret = seq_print_sym_offset(s, "%s", ip); @@ -461,94 +666,186 @@ seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags) return ret; } +/** + * trace_print_lat_fmt - print the irq, preempt and lockdep fields + * @s: trace seq struct to write to + * @entry: The trace entry field from the ring buffer + * + * Prints the generic fields of irqs off, in hard or softirq, preempt + * count. + */ +int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry) +{ + char hardsoft_irq; + char need_resched; + char irqs_off; + int hardirq; + int softirq; + int ret; + + hardirq = entry->flags & TRACE_FLAG_HARDIRQ; + softirq = entry->flags & TRACE_FLAG_SOFTIRQ; + + irqs_off = + (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : + (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' : + '.'; + + switch (entry->flags & (TRACE_FLAG_NEED_RESCHED | + TRACE_FLAG_PREEMPT_RESCHED)) { + case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED: + need_resched = 'N'; + break; + case TRACE_FLAG_NEED_RESCHED: + need_resched = 'n'; + break; + case TRACE_FLAG_PREEMPT_RESCHED: + need_resched = 'p'; + break; + default: + need_resched = '.'; + break; + } + + hardsoft_irq = + (hardirq && softirq) ? 'H' : + hardirq ? 'h' : + softirq ? 's' : + '.'; + + if (!trace_seq_printf(s, "%c%c%c", + irqs_off, need_resched, hardsoft_irq)) + return 0; + + if (entry->preempt_count) + ret = trace_seq_printf(s, "%x", entry->preempt_count); + else + ret = trace_seq_putc(s, '.'); + + return ret; +} + static int lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu) { - int hardirq, softirq; char comm[TASK_COMM_LEN]; trace_find_cmdline(entry->pid, comm); - hardirq = entry->flags & TRACE_FLAG_HARDIRQ; - softirq = entry->flags & TRACE_FLAG_SOFTIRQ; - if (!trace_seq_printf(s, "%8.8s-%-5d %3d%c%c%c", - comm, entry->pid, cpu, - (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : - (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? - 'X' : '.', - (entry->flags & TRACE_FLAG_NEED_RESCHED) ? - 'N' : '.', - (hardirq && softirq) ? 'H' : - hardirq ? 'h' : softirq ? 's' : '.')) + if (!trace_seq_printf(s, "%8.8s-%-5d %3d", + comm, entry->pid, cpu)) return 0; - if (entry->preempt_count) - return trace_seq_printf(s, "%x", entry->preempt_count); - return trace_seq_puts(s, "."); + return trace_print_lat_fmt(s, entry); } -static unsigned long preempt_mark_thresh = 100; +static unsigned long preempt_mark_thresh_us = 100; static int -lat_print_timestamp(struct trace_seq *s, u64 abs_usecs, - unsigned long rel_usecs) +lat_print_timestamp(struct trace_iterator *iter, u64 next_ts) { - return trace_seq_printf(s, " %4lldus%c: ", abs_usecs, - rel_usecs > preempt_mark_thresh ? '!' : - rel_usecs > 1 ? '+' : ' '); + unsigned long verbose = trace_flags & TRACE_ITER_VERBOSE; + unsigned long in_ns = iter->iter_flags & TRACE_FILE_TIME_IN_NS; + unsigned long long abs_ts = iter->ts - iter->trace_buffer->time_start; + unsigned long long rel_ts = next_ts - iter->ts; + struct trace_seq *s = &iter->seq; + + if (in_ns) { + abs_ts = ns2usecs(abs_ts); + rel_ts = ns2usecs(rel_ts); + } + + if (verbose && in_ns) { + unsigned long abs_usec = do_div(abs_ts, USEC_PER_MSEC); + unsigned long abs_msec = (unsigned long)abs_ts; + unsigned long rel_usec = do_div(rel_ts, USEC_PER_MSEC); + unsigned long rel_msec = (unsigned long)rel_ts; + + return trace_seq_printf( + s, "[%08llx] %ld.%03ldms (+%ld.%03ldms): ", + ns2usecs(iter->ts), + abs_msec, abs_usec, + rel_msec, rel_usec); + } else if (verbose && !in_ns) { + return trace_seq_printf( + s, "[%016llx] %lld (+%lld): ", + iter->ts, abs_ts, rel_ts); + } else if (!verbose && in_ns) { + return trace_seq_printf( + s, " %4lldus%c: ", + abs_ts, + rel_ts > preempt_mark_thresh_us ? '!' : + rel_ts > 1 ? '+' : ' '); + } else { /* !verbose && !in_ns */ + return trace_seq_printf(s, " %4lld: ", abs_ts); + } } int trace_print_context(struct trace_iterator *iter) { struct trace_seq *s = &iter->seq; struct trace_entry *entry = iter->ent; - unsigned long long t = ns2usecs(iter->ts); - unsigned long usec_rem = do_div(t, USEC_PER_SEC); - unsigned long secs = (unsigned long)t; + unsigned long long t; + unsigned long secs, usec_rem; char comm[TASK_COMM_LEN]; + int ret; trace_find_cmdline(entry->pid, comm); - return trace_seq_printf(s, "%16s-%-5d [%03d] %5lu.%06lu: ", - comm, entry->pid, iter->cpu, secs, usec_rem); + ret = trace_seq_printf(s, "%16s-%-5d [%03d] ", + comm, entry->pid, iter->cpu); + if (!ret) + return 0; + + if (trace_flags & TRACE_ITER_IRQ_INFO) { + ret = trace_print_lat_fmt(s, entry); + if (!ret) + return 0; + } + + if (iter->iter_flags & TRACE_FILE_TIME_IN_NS) { + t = ns2usecs(iter->ts); + usec_rem = do_div(t, USEC_PER_SEC); + secs = (unsigned long)t; + return trace_seq_printf(s, " %5lu.%06lu: ", secs, usec_rem); + } else + return trace_seq_printf(s, " %12llu: ", iter->ts); } int trace_print_lat_context(struct trace_iterator *iter) { u64 next_ts; int ret; + /* trace_find_next_entry will reset ent_size */ + int ent_size = iter->ent_size; struct trace_seq *s = &iter->seq; struct trace_entry *entry = iter->ent, *next_entry = trace_find_next_entry(iter, NULL, &next_ts); unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE); - unsigned long abs_usecs = ns2usecs(iter->ts - iter->tr->time_start); - unsigned long rel_usecs; + + /* Restore the original ent_size */ + iter->ent_size = ent_size; if (!next_entry) next_ts = iter->ts; - rel_usecs = ns2usecs(next_ts - iter->ts); if (verbose) { char comm[TASK_COMM_LEN]; trace_find_cmdline(entry->pid, comm); - ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08llx]" - " %ld.%03ldms (+%ld.%03ldms): ", comm, - entry->pid, iter->cpu, entry->flags, - entry->preempt_count, iter->idx, - ns2usecs(iter->ts), - abs_usecs / USEC_PER_MSEC, - abs_usecs % USEC_PER_MSEC, - rel_usecs / USEC_PER_MSEC, - rel_usecs % USEC_PER_MSEC); + ret = trace_seq_printf( + s, "%16s %5d %3d %d %08x %08lx ", + comm, entry->pid, iter->cpu, entry->flags, + entry->preempt_count, iter->idx); } else { ret = lat_print_generic(s, entry, iter->cpu); - if (ret) - ret = lat_print_timestamp(s, abs_usecs, rel_usecs); } + if (ret) + ret = lat_print_timestamp(iter, next_ts); + return ret; } @@ -571,12 +868,11 @@ static int task_state_char(unsigned long state) struct trace_event *ftrace_find_event(int type) { struct trace_event *event; - struct hlist_node *n; unsigned key; key = type & (EVENT_HASHSIZE - 1); - hlist_for_each_entry(event, n, &event_hash[key], node) { + hlist_for_each_entry(event, &event_hash[key], node) { if (event->type == type) return event; } @@ -616,12 +912,12 @@ static int trace_search_list(struct list_head **list) void trace_event_read_lock(void) { - down_read(&trace_event_mutex); + down_read(&trace_event_sem); } void trace_event_read_unlock(void) { - up_read(&trace_event_mutex); + up_read(&trace_event_sem); } /** @@ -644,11 +940,14 @@ int register_ftrace_event(struct trace_event *event) unsigned key; int ret = 0; - down_write(&trace_event_mutex); + down_write(&trace_event_sem); if (WARN_ON(!event)) goto out; + if (WARN_ON(!event->funcs)) + goto out; + INIT_LIST_HEAD(&event->list); if (!event->type) { @@ -681,14 +980,14 @@ int register_ftrace_event(struct trace_event *event) goto out; } - if (event->trace == NULL) - event->trace = trace_nop_print; - if (event->raw == NULL) - event->raw = trace_nop_print; - if (event->hex == NULL) - event->hex = trace_nop_print; - if (event->binary == NULL) - event->binary = trace_nop_print; + if (event->funcs->trace == NULL) + event->funcs->trace = trace_nop_print; + if (event->funcs->raw == NULL) + event->funcs->raw = trace_nop_print; + if (event->funcs->hex == NULL) + event->funcs->hex = trace_nop_print; + if (event->funcs->binary == NULL) + event->funcs->binary = trace_nop_print; key = event->type & (EVENT_HASHSIZE - 1); @@ -696,14 +995,14 @@ int register_ftrace_event(struct trace_event *event) ret = event->type; out: - up_write(&trace_event_mutex); + up_write(&trace_event_sem); return ret; } EXPORT_SYMBOL_GPL(register_ftrace_event); /* - * Used by module code with the trace_event_mutex held for write. + * Used by module code with the trace_event_sem held for write. */ int __unregister_ftrace_event(struct trace_event *event) { @@ -718,9 +1017,9 @@ int __unregister_ftrace_event(struct trace_event *event) */ int unregister_ftrace_event(struct trace_event *event) { - down_write(&trace_event_mutex); + down_write(&trace_event_sem); __unregister_ftrace_event(event); - up_write(&trace_event_mutex); + up_write(&trace_event_sem); return 0; } @@ -730,13 +1029,18 @@ EXPORT_SYMBOL_GPL(unregister_ftrace_event); * Standard events */ -enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags) +enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags, + struct trace_event *event) { + if (!trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type)) + return TRACE_TYPE_PARTIAL_LINE; + return TRACE_TYPE_HANDLED; } /* TRACE_FN */ -static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags) +static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags, + struct trace_event *event) { struct ftrace_entry *field; struct trace_seq *s = &iter->seq; @@ -747,14 +1051,14 @@ static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags) goto partial; if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) { - if (!trace_seq_printf(s, " <-")) + if (!trace_seq_puts(s, " <-")) goto partial; if (!seq_print_ip_sym(s, field->parent_ip, flags)) goto partial; } - if (!trace_seq_printf(s, "\n")) + if (!trace_seq_putc(s, '\n')) goto partial; return TRACE_TYPE_HANDLED; @@ -763,7 +1067,8 @@ static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags) return TRACE_TYPE_PARTIAL_LINE; } -static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags) +static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags, + struct trace_event *event) { struct ftrace_entry *field; @@ -777,7 +1082,8 @@ static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags) return TRACE_TYPE_HANDLED; } -static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags) +static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags, + struct trace_event *event) { struct ftrace_entry *field; struct trace_seq *s = &iter->seq; @@ -790,7 +1096,8 @@ static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags) return TRACE_TYPE_HANDLED; } -static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags) +static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags, + struct trace_event *event) { struct ftrace_entry *field; struct trace_seq *s = &iter->seq; @@ -803,14 +1110,18 @@ static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags) return TRACE_TYPE_HANDLED; } -static struct trace_event trace_fn_event = { - .type = TRACE_FN, +static struct trace_event_functions trace_fn_funcs = { .trace = trace_fn_trace, .raw = trace_fn_raw, .hex = trace_fn_hex, .binary = trace_fn_bin, }; +static struct trace_event trace_fn_event = { + .type = TRACE_FN, + .funcs = &trace_fn_funcs, +}; + /* TRACE_CTX an TRACE_WAKE */ static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter, char *delim) @@ -839,13 +1150,14 @@ static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter, return TRACE_TYPE_HANDLED; } -static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags) +static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags, + struct trace_event *event) { return trace_ctxwake_print(iter, "==>"); } static enum print_line_t trace_wake_print(struct trace_iterator *iter, - int flags) + int flags, struct trace_event *event) { return trace_ctxwake_print(iter, " +"); } @@ -858,7 +1170,7 @@ static int trace_ctxwake_raw(struct trace_iterator *iter, char S) trace_assign_type(field, iter->ent); if (!S) - task_state_char(field->prev_state); + S = task_state_char(field->prev_state); T = task_state_char(field->next_state); if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n", field->prev_pid, @@ -873,12 +1185,14 @@ static int trace_ctxwake_raw(struct trace_iterator *iter, char S) return TRACE_TYPE_HANDLED; } -static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags) +static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags, + struct trace_event *event) { return trace_ctxwake_raw(iter, 0); } -static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags) +static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags, + struct trace_event *event) { return trace_ctxwake_raw(iter, '+'); } @@ -893,7 +1207,7 @@ static int trace_ctxwake_hex(struct trace_iterator *iter, char S) trace_assign_type(field, iter->ent); if (!S) - task_state_char(field->prev_state); + S = task_state_char(field->prev_state); T = task_state_char(field->next_state); SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid); @@ -907,18 +1221,20 @@ static int trace_ctxwake_hex(struct trace_iterator *iter, char S) return TRACE_TYPE_HANDLED; } -static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags) +static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags, + struct trace_event *event) { return trace_ctxwake_hex(iter, 0); } -static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags) +static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags, + struct trace_event *event) { return trace_ctxwake_hex(iter, '+'); } static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter, - int flags) + int flags, struct trace_event *event) { struct ctx_switch_entry *field; struct trace_seq *s = &iter->seq; @@ -935,99 +1251,53 @@ static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter, return TRACE_TYPE_HANDLED; } -static struct trace_event trace_ctx_event = { - .type = TRACE_CTX, +static struct trace_event_functions trace_ctx_funcs = { .trace = trace_ctx_print, .raw = trace_ctx_raw, .hex = trace_ctx_hex, .binary = trace_ctxwake_bin, }; -static struct trace_event trace_wake_event = { - .type = TRACE_WAKE, +static struct trace_event trace_ctx_event = { + .type = TRACE_CTX, + .funcs = &trace_ctx_funcs, +}; + +static struct trace_event_functions trace_wake_funcs = { .trace = trace_wake_print, .raw = trace_wake_raw, .hex = trace_wake_hex, .binary = trace_ctxwake_bin, }; -/* TRACE_SPECIAL */ -static enum print_line_t trace_special_print(struct trace_iterator *iter, - int flags) -{ - struct special_entry *field; - - trace_assign_type(field, iter->ent); - - if (!trace_seq_printf(&iter->seq, "# %ld %ld %ld\n", - field->arg1, - field->arg2, - field->arg3)) - return TRACE_TYPE_PARTIAL_LINE; - - return TRACE_TYPE_HANDLED; -} - -static enum print_line_t trace_special_hex(struct trace_iterator *iter, - int flags) -{ - struct special_entry *field; - struct trace_seq *s = &iter->seq; - - trace_assign_type(field, iter->ent); - - SEQ_PUT_HEX_FIELD_RET(s, field->arg1); - SEQ_PUT_HEX_FIELD_RET(s, field->arg2); - SEQ_PUT_HEX_FIELD_RET(s, field->arg3); - - return TRACE_TYPE_HANDLED; -} - -static enum print_line_t trace_special_bin(struct trace_iterator *iter, - int flags) -{ - struct special_entry *field; - struct trace_seq *s = &iter->seq; - - trace_assign_type(field, iter->ent); - - SEQ_PUT_FIELD_RET(s, field->arg1); - SEQ_PUT_FIELD_RET(s, field->arg2); - SEQ_PUT_FIELD_RET(s, field->arg3); - - return TRACE_TYPE_HANDLED; -} - -static struct trace_event trace_special_event = { - .type = TRACE_SPECIAL, - .trace = trace_special_print, - .raw = trace_special_print, - .hex = trace_special_hex, - .binary = trace_special_bin, +static struct trace_event trace_wake_event = { + .type = TRACE_WAKE, + .funcs = &trace_wake_funcs, }; /* TRACE_STACK */ static enum print_line_t trace_stack_print(struct trace_iterator *iter, - int flags) + int flags, struct trace_event *event) { struct stack_entry *field; struct trace_seq *s = &iter->seq; - int i; + unsigned long *p; + unsigned long *end; trace_assign_type(field, iter->ent); + end = (unsigned long *)((long)iter->ent + iter->ent_size); if (!trace_seq_puts(s, "<stack trace>\n")) goto partial; - for (i = 0; i < FTRACE_STACK_ENTRIES; i++) { - if (!field->caller[i] || (field->caller[i] == ULONG_MAX)) - break; + + for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) { if (!trace_seq_puts(s, " => ")) goto partial; - if (!seq_print_ip_sym(s, field->caller[i], flags)) + if (!seq_print_ip_sym(s, *p, flags)) goto partial; - if (!trace_seq_puts(s, "\n")) + if (!trace_seq_putc(s, '\n')) goto partial; } @@ -1037,17 +1307,18 @@ static enum print_line_t trace_stack_print(struct trace_iterator *iter, return TRACE_TYPE_PARTIAL_LINE; } +static struct trace_event_functions trace_stack_funcs = { + .trace = trace_stack_print, +}; + static struct trace_event trace_stack_event = { .type = TRACE_STACK, - .trace = trace_stack_print, - .raw = trace_special_print, - .hex = trace_special_hex, - .binary = trace_special_bin, + .funcs = &trace_stack_funcs, }; /* TRACE_USER_STACK */ static enum print_line_t trace_user_stack_print(struct trace_iterator *iter, - int flags) + int flags, struct trace_event *event) { struct userstack_entry *field; struct trace_seq *s = &iter->seq; @@ -1066,17 +1337,77 @@ static enum print_line_t trace_user_stack_print(struct trace_iterator *iter, return TRACE_TYPE_PARTIAL_LINE; } +static struct trace_event_functions trace_user_stack_funcs = { + .trace = trace_user_stack_print, +}; + static struct trace_event trace_user_stack_event = { .type = TRACE_USER_STACK, - .trace = trace_user_stack_print, - .raw = trace_special_print, - .hex = trace_special_hex, - .binary = trace_special_bin, + .funcs = &trace_user_stack_funcs, +}; + +/* TRACE_BPUTS */ +static enum print_line_t +trace_bputs_print(struct trace_iterator *iter, int flags, + struct trace_event *event) +{ + struct trace_entry *entry = iter->ent; + struct trace_seq *s = &iter->seq; + struct bputs_entry *field; + + trace_assign_type(field, entry); + + if (!seq_print_ip_sym(s, field->ip, flags)) + goto partial; + + if (!trace_seq_puts(s, ": ")) + goto partial; + + if (!trace_seq_puts(s, field->str)) + goto partial; + + return TRACE_TYPE_HANDLED; + + partial: + return TRACE_TYPE_PARTIAL_LINE; +} + + +static enum print_line_t +trace_bputs_raw(struct trace_iterator *iter, int flags, + struct trace_event *event) +{ + struct bputs_entry *field; + struct trace_seq *s = &iter->seq; + + trace_assign_type(field, iter->ent); + + if (!trace_seq_printf(s, ": %lx : ", field->ip)) + goto partial; + + if (!trace_seq_puts(s, field->str)) + goto partial; + + return TRACE_TYPE_HANDLED; + + partial: + return TRACE_TYPE_PARTIAL_LINE; +} + +static struct trace_event_functions trace_bputs_funcs = { + .trace = trace_bputs_print, + .raw = trace_bputs_raw, +}; + +static struct trace_event trace_bputs_event = { + .type = TRACE_BPUTS, + .funcs = &trace_bputs_funcs, }; /* TRACE_BPRINT */ static enum print_line_t -trace_bprint_print(struct trace_iterator *iter, int flags) +trace_bprint_print(struct trace_iterator *iter, int flags, + struct trace_event *event) { struct trace_entry *entry = iter->ent; struct trace_seq *s = &iter->seq; @@ -1101,7 +1432,8 @@ trace_bprint_print(struct trace_iterator *iter, int flags) static enum print_line_t -trace_bprint_raw(struct trace_iterator *iter, int flags) +trace_bprint_raw(struct trace_iterator *iter, int flags, + struct trace_event *event) { struct bprint_entry *field; struct trace_seq *s = &iter->seq; @@ -1120,16 +1452,19 @@ trace_bprint_raw(struct trace_iterator *iter, int flags) return TRACE_TYPE_PARTIAL_LINE; } +static struct trace_event_functions trace_bprint_funcs = { + .trace = trace_bprint_print, + .raw = trace_bprint_raw, +}; static struct trace_event trace_bprint_event = { .type = TRACE_BPRINT, - .trace = trace_bprint_print, - .raw = trace_bprint_raw, + .funcs = &trace_bprint_funcs, }; /* TRACE_PRINT */ static enum print_line_t trace_print_print(struct trace_iterator *iter, - int flags) + int flags, struct trace_event *event) { struct print_entry *field; struct trace_seq *s = &iter->seq; @@ -1148,7 +1483,8 @@ static enum print_line_t trace_print_print(struct trace_iterator *iter, return TRACE_TYPE_PARTIAL_LINE; } -static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags) +static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags, + struct trace_event *event) { struct print_entry *field; @@ -1163,20 +1499,24 @@ static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags) return TRACE_TYPE_PARTIAL_LINE; } -static struct trace_event trace_print_event = { - .type = TRACE_PRINT, +static struct trace_event_functions trace_print_funcs = { .trace = trace_print_print, .raw = trace_print_raw, }; +static struct trace_event trace_print_event = { + .type = TRACE_PRINT, + .funcs = &trace_print_funcs, +}; + static struct trace_event *events[] __initdata = { &trace_fn_event, &trace_ctx_event, &trace_wake_event, - &trace_special_event, &trace_stack_event, &trace_user_stack_event, + &trace_bputs_event, &trace_bprint_event, &trace_print_event, NULL @@ -1200,4 +1540,4 @@ __init static int init_events(void) return 0; } -device_initcall(init_events); +early_initcall(init_events); diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h index d38bec4a9c3..127a9d8c835 100644 --- a/kernel/trace/trace_output.h +++ b/kernel/trace/trace_output.h @@ -5,6 +5,8 @@ #include "trace.h" extern enum print_line_t +trace_print_bputs_msg_only(struct trace_iterator *iter); +extern enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter); extern enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter); @@ -25,11 +27,13 @@ extern void trace_event_read_unlock(void); extern struct trace_event *ftrace_find_event(int type); extern enum print_line_t trace_nop_print(struct trace_iterator *iter, - int flags); + int flags, struct trace_event *event); +extern int +trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry); /* used by module unregistering */ extern int __unregister_ftrace_event(struct trace_event *event); -extern struct rw_semaphore trace_event_mutex; +extern struct rw_semaphore trace_event_sem; #define MAX_MEMHEX_BYTES 8 #define HEX_CHARS (MAX_MEMHEX_BYTES*2 + 1) diff --git a/kernel/trace/trace_power.c b/kernel/trace/trace_power.c deleted file mode 100644 index 8a30d9874cd..00000000000 --- a/kernel/trace/trace_power.c +++ /dev/null @@ -1,214 +0,0 @@ -/* - * ring buffer based C-state tracer - * - * Arjan van de Ven <arjan@linux.intel.com> - * Copyright (C) 2008 Intel Corporation - * - * Much is borrowed from trace_boot.c which is - * Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com> - * - */ - -#include <linux/init.h> -#include <linux/debugfs.h> -#include <trace/power.h> -#include <linux/kallsyms.h> -#include <linux/module.h> - -#include "trace.h" -#include "trace_output.h" - -static struct trace_array *power_trace; -static int __read_mostly trace_power_enabled; - -static void probe_power_start(struct power_trace *it, unsigned int type, - unsigned int level) -{ - if (!trace_power_enabled) - return; - - memset(it, 0, sizeof(struct power_trace)); - it->state = level; - it->type = type; - it->stamp = ktime_get(); -} - - -static void probe_power_end(struct power_trace *it) -{ - struct ftrace_event_call *call = &event_power; - struct ring_buffer_event *event; - struct trace_power *entry; - struct trace_array_cpu *data; - struct trace_array *tr = power_trace; - - if (!trace_power_enabled) - return; - - preempt_disable(); - it->end = ktime_get(); - data = tr->data[smp_processor_id()]; - - event = trace_buffer_lock_reserve(tr, TRACE_POWER, - sizeof(*entry), 0, 0); - if (!event) - goto out; - entry = ring_buffer_event_data(event); - entry->state_data = *it; - if (!filter_check_discard(call, entry, tr->buffer, event)) - trace_buffer_unlock_commit(tr, event, 0, 0); - out: - preempt_enable(); -} - -static void probe_power_mark(struct power_trace *it, unsigned int type, - unsigned int level) -{ - struct ftrace_event_call *call = &event_power; - struct ring_buffer_event *event; - struct trace_power *entry; - struct trace_array_cpu *data; - struct trace_array *tr = power_trace; - - if (!trace_power_enabled) - return; - - memset(it, 0, sizeof(struct power_trace)); - it->state = level; - it->type = type; - it->stamp = ktime_get(); - preempt_disable(); - it->end = it->stamp; - data = tr->data[smp_processor_id()]; - - event = trace_buffer_lock_reserve(tr, TRACE_POWER, - sizeof(*entry), 0, 0); - if (!event) - goto out; - entry = ring_buffer_event_data(event); - entry->state_data = *it; - if (!filter_check_discard(call, entry, tr->buffer, event)) - trace_buffer_unlock_commit(tr, event, 0, 0); - out: - preempt_enable(); -} - -static int tracing_power_register(void) -{ - int ret; - - ret = register_trace_power_start(probe_power_start); - if (ret) { - pr_info("power trace: Couldn't activate tracepoint" - " probe to trace_power_start\n"); - return ret; - } - ret = register_trace_power_end(probe_power_end); - if (ret) { - pr_info("power trace: Couldn't activate tracepoint" - " probe to trace_power_end\n"); - goto fail_start; - } - ret = register_trace_power_mark(probe_power_mark); - if (ret) { - pr_info("power trace: Couldn't activate tracepoint" - " probe to trace_power_mark\n"); - goto fail_end; - } - return ret; -fail_end: - unregister_trace_power_end(probe_power_end); -fail_start: - unregister_trace_power_start(probe_power_start); - return ret; -} - -static void start_power_trace(struct trace_array *tr) -{ - trace_power_enabled = 1; -} - -static void stop_power_trace(struct trace_array *tr) -{ - trace_power_enabled = 0; -} - -static void power_trace_reset(struct trace_array *tr) -{ - trace_power_enabled = 0; - unregister_trace_power_start(probe_power_start); - unregister_trace_power_end(probe_power_end); - unregister_trace_power_mark(probe_power_mark); -} - - -static int power_trace_init(struct trace_array *tr) -{ - int cpu; - power_trace = tr; - - trace_power_enabled = 1; - tracing_power_register(); - - for_each_cpu(cpu, cpu_possible_mask) - tracing_reset(tr, cpu); - return 0; -} - -static enum print_line_t power_print_line(struct trace_iterator *iter) -{ - int ret = 0; - struct trace_entry *entry = iter->ent; - struct trace_power *field ; - struct power_trace *it; - struct trace_seq *s = &iter->seq; - struct timespec stamp; - struct timespec duration; - - trace_assign_type(field, entry); - it = &field->state_data; - stamp = ktime_to_timespec(it->stamp); - duration = ktime_to_timespec(ktime_sub(it->end, it->stamp)); - - if (entry->type == TRACE_POWER) { - if (it->type == POWER_CSTATE) - ret = trace_seq_printf(s, "[%5ld.%09ld] CSTATE: Going to C%i on cpu %i for %ld.%09ld\n", - stamp.tv_sec, - stamp.tv_nsec, - it->state, iter->cpu, - duration.tv_sec, - duration.tv_nsec); - if (it->type == POWER_PSTATE) - ret = trace_seq_printf(s, "[%5ld.%09ld] PSTATE: Going to P%i on cpu %i\n", - stamp.tv_sec, - stamp.tv_nsec, - it->state, iter->cpu); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - return TRACE_TYPE_HANDLED; - } - return TRACE_TYPE_UNHANDLED; -} - -static void power_print_header(struct seq_file *s) -{ - seq_puts(s, "# TIMESTAMP STATE EVENT\n"); - seq_puts(s, "# | | |\n"); -} - -static struct tracer power_tracer __read_mostly = -{ - .name = "power", - .init = power_trace_init, - .start = start_power_trace, - .stop = stop_power_trace, - .reset = power_trace_reset, - .print_line = power_print_line, - .print_header = power_print_header, -}; - -static int init_power_trace(void) -{ - return register_tracer(&power_tracer); -} -device_initcall(init_power_trace); diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c index 7b627811082..2900817ba65 100644 --- a/kernel/trace/trace_printk.c +++ b/kernel/trace/trace_printk.c @@ -11,7 +11,6 @@ #include <linux/ftrace.h> #include <linux/string.h> #include <linux/module.h> -#include <linux/marker.h> #include <linux/mutex.h> #include <linux/ctype.h> #include <linux/list.h> @@ -33,7 +32,7 @@ static DEFINE_MUTEX(btrace_mutex); struct trace_bprintk_fmt { struct list_head list; - char fmt[0]; + const char *fmt; }; static inline struct trace_bprintk_fmt *lookup_format(const char *fmt) @@ -50,6 +49,11 @@ static void hold_module_trace_bprintk_format(const char **start, const char **end) { const char **iter; + char *fmt; + + /* allocate the trace_printk per cpu buffers */ + if (start != end) + trace_printk_init_buffers(); mutex_lock(&btrace_mutex); for (iter = start; iter < end; iter++) { @@ -59,14 +63,19 @@ void hold_module_trace_bprintk_format(const char **start, const char **end) continue; } - tb_fmt = kmalloc(offsetof(struct trace_bprintk_fmt, fmt) - + strlen(*iter) + 1, GFP_KERNEL); + fmt = NULL; + tb_fmt = kmalloc(sizeof(*tb_fmt), GFP_KERNEL); if (tb_fmt) { - list_add_tail(&tb_fmt->list, &trace_bprintk_fmt_list); - strcpy(tb_fmt->fmt, *iter); - *iter = tb_fmt->fmt; - } else - *iter = NULL; + fmt = kmalloc(strlen(*iter) + 1, GFP_KERNEL); + if (fmt) { + list_add_tail(&tb_fmt->list, &trace_bprintk_fmt_list); + strcpy(fmt, *iter); + tb_fmt->fmt = fmt; + } else + kfree(tb_fmt); + } + *iter = fmt; + } mutex_unlock(&btrace_mutex); } @@ -85,6 +94,76 @@ static int module_trace_bprintk_format_notify(struct notifier_block *self, return 0; } +/* + * The debugfs/tracing/printk_formats file maps the addresses with + * the ASCII formats that are used in the bprintk events in the + * buffer. For userspace tools to be able to decode the events from + * the buffer, they need to be able to map the address with the format. + * + * The addresses of the bprintk formats are in their own section + * __trace_printk_fmt. But for modules we copy them into a link list. + * The code to print the formats and their addresses passes around the + * address of the fmt string. If the fmt address passed into the seq + * functions is within the kernel core __trace_printk_fmt section, then + * it simply uses the next pointer in the list. + * + * When the fmt pointer is outside the kernel core __trace_printk_fmt + * section, then we need to read the link list pointers. The trick is + * we pass the address of the string to the seq function just like + * we do for the kernel core formats. To get back the structure that + * holds the format, we simply use containerof() and then go to the + * next format in the list. + */ +static const char ** +find_next_mod_format(int start_index, void *v, const char **fmt, loff_t *pos) +{ + struct trace_bprintk_fmt *mod_fmt; + + if (list_empty(&trace_bprintk_fmt_list)) + return NULL; + + /* + * v will point to the address of the fmt record from t_next + * v will be NULL from t_start. + * If this is the first pointer or called from start + * then we need to walk the list. + */ + if (!v || start_index == *pos) { + struct trace_bprintk_fmt *p; + + /* search the module list */ + list_for_each_entry(p, &trace_bprintk_fmt_list, list) { + if (start_index == *pos) + return &p->fmt; + start_index++; + } + /* pos > index */ + return NULL; + } + + /* + * v points to the address of the fmt field in the mod list + * structure that holds the module print format. + */ + mod_fmt = container_of(v, typeof(*mod_fmt), fmt); + if (mod_fmt->list.next == &trace_bprintk_fmt_list) + return NULL; + + mod_fmt = container_of(mod_fmt->list.next, typeof(*mod_fmt), list); + + return &mod_fmt->fmt; +} + +static void format_mod_start(void) +{ + mutex_lock(&btrace_mutex); +} + +static void format_mod_stop(void) +{ + mutex_unlock(&btrace_mutex); +} + #else /* !CONFIG_MODULES */ __init static int module_trace_bprintk_format_notify(struct notifier_block *self, @@ -92,6 +171,13 @@ module_trace_bprintk_format_notify(struct notifier_block *self, { return 0; } +static inline const char ** +find_next_mod_format(int start_index, void *v, const char **fmt, loff_t *pos) +{ + return NULL; +} +static inline void format_mod_start(void) { } +static inline void format_mod_stop(void) { } #endif /* CONFIG_MODULES */ @@ -154,20 +240,49 @@ int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap) } EXPORT_SYMBOL_GPL(__ftrace_vprintk); +static const char **find_next(void *v, loff_t *pos) +{ + const char **fmt = v; + int start_index; + int last_index; + + start_index = __stop___trace_bprintk_fmt - __start___trace_bprintk_fmt; + + if (*pos < start_index) + return __start___trace_bprintk_fmt + *pos; + + /* + * The __tracepoint_str section is treated the same as the + * __trace_printk_fmt section. The difference is that the + * __trace_printk_fmt section should only be used by trace_printk() + * in a debugging environment, as if anything exists in that section + * the trace_prink() helper buffers are allocated, which would just + * waste space in a production environment. + * + * The __tracepoint_str sections on the other hand are used by + * tracepoints which need to map pointers to their strings to + * the ASCII text for userspace. + */ + last_index = start_index; + start_index = __stop___tracepoint_str - __start___tracepoint_str; + + if (*pos < last_index + start_index) + return __start___tracepoint_str + (*pos - last_index); + + return find_next_mod_format(start_index, v, fmt, pos); +} + static void * t_start(struct seq_file *m, loff_t *pos) { - const char **fmt = __start___trace_bprintk_fmt + *pos; - - if ((unsigned long)fmt >= (unsigned long)__stop___trace_bprintk_fmt) - return NULL; - return fmt; + format_mod_start(); + return find_next(NULL, pos); } static void *t_next(struct seq_file *m, void * v, loff_t *pos) { (*pos)++; - return t_start(m, pos); + return find_next(v, pos); } static int t_show(struct seq_file *m, void *v) @@ -176,7 +291,7 @@ static int t_show(struct seq_file *m, void *v) const char *str = *fmt; int i; - seq_printf(m, "0x%lx : \"", (unsigned long)fmt); + seq_printf(m, "0x%lx : \"", *(unsigned long *)fmt); /* * Tabs and new lines need to be converted. @@ -206,6 +321,7 @@ static int t_show(struct seq_file *m, void *v) static void t_stop(struct seq_file *m, void *p) { + format_mod_stop(); } static const struct seq_operations show_format_seq_ops = { diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c new file mode 100644 index 00000000000..d4b9fc22cd2 --- /dev/null +++ b/kernel/trace/trace_probe.c @@ -0,0 +1,726 @@ +/* + * Common code for probe-based Dynamic events. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * This code was copied from kernel/trace/trace_kprobe.c written by + * Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> + * + * Updates to make this generic: + * Copyright (C) IBM Corporation, 2010-2011 + * Author: Srikar Dronamraju + */ + +#include "trace_probe.h" + +const char *reserved_field_names[] = { + "common_type", + "common_flags", + "common_preempt_count", + "common_pid", + "common_tgid", + FIELD_STRING_IP, + FIELD_STRING_RETIP, + FIELD_STRING_FUNC, +}; + +/* Printing in basic type function template */ +#define DEFINE_BASIC_PRINT_TYPE_FUNC(type, fmt) \ +int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, const char *name, \ + void *data, void *ent) \ +{ \ + return trace_seq_printf(s, " %s=" fmt, name, *(type *)data); \ +} \ +const char PRINT_TYPE_FMT_NAME(type)[] = fmt; \ +NOKPROBE_SYMBOL(PRINT_TYPE_FUNC_NAME(type)); + +DEFINE_BASIC_PRINT_TYPE_FUNC(u8 , "0x%x") +DEFINE_BASIC_PRINT_TYPE_FUNC(u16, "0x%x") +DEFINE_BASIC_PRINT_TYPE_FUNC(u32, "0x%x") +DEFINE_BASIC_PRINT_TYPE_FUNC(u64, "0x%Lx") +DEFINE_BASIC_PRINT_TYPE_FUNC(s8, "%d") +DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d") +DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%d") +DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%Ld") + +/* Print type function for string type */ +int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, const char *name, + void *data, void *ent) +{ + int len = *(u32 *)data >> 16; + + if (!len) + return trace_seq_printf(s, " %s=(fault)", name); + else + return trace_seq_printf(s, " %s=\"%s\"", name, + (const char *)get_loc_data(data, ent)); +} +NOKPROBE_SYMBOL(PRINT_TYPE_FUNC_NAME(string)); + +const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\""; + +#define CHECK_FETCH_FUNCS(method, fn) \ + (((FETCH_FUNC_NAME(method, u8) == fn) || \ + (FETCH_FUNC_NAME(method, u16) == fn) || \ + (FETCH_FUNC_NAME(method, u32) == fn) || \ + (FETCH_FUNC_NAME(method, u64) == fn) || \ + (FETCH_FUNC_NAME(method, string) == fn) || \ + (FETCH_FUNC_NAME(method, string_size) == fn)) \ + && (fn != NULL)) + +/* Data fetch function templates */ +#define DEFINE_FETCH_reg(type) \ +void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs, void *offset, void *dest) \ +{ \ + *(type *)dest = (type)regs_get_register(regs, \ + (unsigned int)((unsigned long)offset)); \ +} \ +NOKPROBE_SYMBOL(FETCH_FUNC_NAME(reg, type)); +DEFINE_BASIC_FETCH_FUNCS(reg) +/* No string on the register */ +#define fetch_reg_string NULL +#define fetch_reg_string_size NULL + +#define DEFINE_FETCH_retval(type) \ +void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs, \ + void *dummy, void *dest) \ +{ \ + *(type *)dest = (type)regs_return_value(regs); \ +} \ +NOKPROBE_SYMBOL(FETCH_FUNC_NAME(retval, type)); +DEFINE_BASIC_FETCH_FUNCS(retval) +/* No string on the retval */ +#define fetch_retval_string NULL +#define fetch_retval_string_size NULL + +/* Dereference memory access function */ +struct deref_fetch_param { + struct fetch_param orig; + long offset; + fetch_func_t fetch; + fetch_func_t fetch_size; +}; + +#define DEFINE_FETCH_deref(type) \ +void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs, \ + void *data, void *dest) \ +{ \ + struct deref_fetch_param *dprm = data; \ + unsigned long addr; \ + call_fetch(&dprm->orig, regs, &addr); \ + if (addr) { \ + addr += dprm->offset; \ + dprm->fetch(regs, (void *)addr, dest); \ + } else \ + *(type *)dest = 0; \ +} \ +NOKPROBE_SYMBOL(FETCH_FUNC_NAME(deref, type)); +DEFINE_BASIC_FETCH_FUNCS(deref) +DEFINE_FETCH_deref(string) + +void FETCH_FUNC_NAME(deref, string_size)(struct pt_regs *regs, + void *data, void *dest) +{ + struct deref_fetch_param *dprm = data; + unsigned long addr; + + call_fetch(&dprm->orig, regs, &addr); + if (addr && dprm->fetch_size) { + addr += dprm->offset; + dprm->fetch_size(regs, (void *)addr, dest); + } else + *(string_size *)dest = 0; +} +NOKPROBE_SYMBOL(FETCH_FUNC_NAME(deref, string_size)); + +static void update_deref_fetch_param(struct deref_fetch_param *data) +{ + if (CHECK_FETCH_FUNCS(deref, data->orig.fn)) + update_deref_fetch_param(data->orig.data); + else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn)) + update_symbol_cache(data->orig.data); +} +NOKPROBE_SYMBOL(update_deref_fetch_param); + +static void free_deref_fetch_param(struct deref_fetch_param *data) +{ + if (CHECK_FETCH_FUNCS(deref, data->orig.fn)) + free_deref_fetch_param(data->orig.data); + else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn)) + free_symbol_cache(data->orig.data); + kfree(data); +} +NOKPROBE_SYMBOL(free_deref_fetch_param); + +/* Bitfield fetch function */ +struct bitfield_fetch_param { + struct fetch_param orig; + unsigned char hi_shift; + unsigned char low_shift; +}; + +#define DEFINE_FETCH_bitfield(type) \ +void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs, \ + void *data, void *dest) \ +{ \ + struct bitfield_fetch_param *bprm = data; \ + type buf = 0; \ + call_fetch(&bprm->orig, regs, &buf); \ + if (buf) { \ + buf <<= bprm->hi_shift; \ + buf >>= bprm->low_shift; \ + } \ + *(type *)dest = buf; \ +} \ +NOKPROBE_SYMBOL(FETCH_FUNC_NAME(bitfield, type)); +DEFINE_BASIC_FETCH_FUNCS(bitfield) +#define fetch_bitfield_string NULL +#define fetch_bitfield_string_size NULL + +static void +update_bitfield_fetch_param(struct bitfield_fetch_param *data) +{ + /* + * Don't check the bitfield itself, because this must be the + * last fetch function. + */ + if (CHECK_FETCH_FUNCS(deref, data->orig.fn)) + update_deref_fetch_param(data->orig.data); + else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn)) + update_symbol_cache(data->orig.data); +} + +static void +free_bitfield_fetch_param(struct bitfield_fetch_param *data) +{ + /* + * Don't check the bitfield itself, because this must be the + * last fetch function. + */ + if (CHECK_FETCH_FUNCS(deref, data->orig.fn)) + free_deref_fetch_param(data->orig.data); + else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn)) + free_symbol_cache(data->orig.data); + + kfree(data); +} + +static const struct fetch_type *find_fetch_type(const char *type, + const struct fetch_type *ftbl) +{ + int i; + + if (!type) + type = DEFAULT_FETCH_TYPE_STR; + + /* Special case: bitfield */ + if (*type == 'b') { + unsigned long bs; + + type = strchr(type, '/'); + if (!type) + goto fail; + + type++; + if (kstrtoul(type, 0, &bs)) + goto fail; + + switch (bs) { + case 8: + return find_fetch_type("u8", ftbl); + case 16: + return find_fetch_type("u16", ftbl); + case 32: + return find_fetch_type("u32", ftbl); + case 64: + return find_fetch_type("u64", ftbl); + default: + goto fail; + } + } + + for (i = 0; ftbl[i].name; i++) { + if (strcmp(type, ftbl[i].name) == 0) + return &ftbl[i]; + } + +fail: + return NULL; +} + +/* Special function : only accept unsigned long */ +static void fetch_kernel_stack_address(struct pt_regs *regs, void *dummy, void *dest) +{ + *(unsigned long *)dest = kernel_stack_pointer(regs); +} +NOKPROBE_SYMBOL(fetch_kernel_stack_address); + +static void fetch_user_stack_address(struct pt_regs *regs, void *dummy, void *dest) +{ + *(unsigned long *)dest = user_stack_pointer(regs); +} +NOKPROBE_SYMBOL(fetch_user_stack_address); + +static fetch_func_t get_fetch_size_function(const struct fetch_type *type, + fetch_func_t orig_fn, + const struct fetch_type *ftbl) +{ + int i; + + if (type != &ftbl[FETCH_TYPE_STRING]) + return NULL; /* Only string type needs size function */ + + for (i = 0; i < FETCH_MTD_END; i++) + if (type->fetch[i] == orig_fn) + return ftbl[FETCH_TYPE_STRSIZE].fetch[i]; + + WARN_ON(1); /* This should not happen */ + + return NULL; +} + +/* Split symbol and offset. */ +int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset) +{ + char *tmp; + int ret; + + if (!offset) + return -EINVAL; + + tmp = strchr(symbol, '+'); + if (tmp) { + /* skip sign because kstrtoul doesn't accept '+' */ + ret = kstrtoul(tmp + 1, 0, offset); + if (ret) + return ret; + + *tmp = '\0'; + } else + *offset = 0; + + return 0; +} + +#define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long)) + +static int parse_probe_vars(char *arg, const struct fetch_type *t, + struct fetch_param *f, bool is_return, + bool is_kprobe) +{ + int ret = 0; + unsigned long param; + + if (strcmp(arg, "retval") == 0) { + if (is_return) + f->fn = t->fetch[FETCH_MTD_retval]; + else + ret = -EINVAL; + } else if (strncmp(arg, "stack", 5) == 0) { + if (arg[5] == '\0') { + if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR)) + return -EINVAL; + + if (is_kprobe) + f->fn = fetch_kernel_stack_address; + else + f->fn = fetch_user_stack_address; + } else if (isdigit(arg[5])) { + ret = kstrtoul(arg + 5, 10, ¶m); + if (ret || (is_kprobe && param > PARAM_MAX_STACK)) + ret = -EINVAL; + else { + f->fn = t->fetch[FETCH_MTD_stack]; + f->data = (void *)param; + } + } else + ret = -EINVAL; + } else + ret = -EINVAL; + + return ret; +} + +/* Recursive argument parser */ +static int parse_probe_arg(char *arg, const struct fetch_type *t, + struct fetch_param *f, bool is_return, bool is_kprobe) +{ + const struct fetch_type *ftbl; + unsigned long param; + long offset; + char *tmp; + int ret = 0; + + ftbl = is_kprobe ? kprobes_fetch_type_table : uprobes_fetch_type_table; + BUG_ON(ftbl == NULL); + + switch (arg[0]) { + case '$': + ret = parse_probe_vars(arg + 1, t, f, is_return, is_kprobe); + break; + + case '%': /* named register */ + ret = regs_query_register_offset(arg + 1); + if (ret >= 0) { + f->fn = t->fetch[FETCH_MTD_reg]; + f->data = (void *)(unsigned long)ret; + ret = 0; + } + break; + + case '@': /* memory, file-offset or symbol */ + if (isdigit(arg[1])) { + ret = kstrtoul(arg + 1, 0, ¶m); + if (ret) + break; + + f->fn = t->fetch[FETCH_MTD_memory]; + f->data = (void *)param; + } else if (arg[1] == '+') { + /* kprobes don't support file offsets */ + if (is_kprobe) + return -EINVAL; + + ret = kstrtol(arg + 2, 0, &offset); + if (ret) + break; + + f->fn = t->fetch[FETCH_MTD_file_offset]; + f->data = (void *)offset; + } else { + /* uprobes don't support symbols */ + if (!is_kprobe) + return -EINVAL; + + ret = traceprobe_split_symbol_offset(arg + 1, &offset); + if (ret) + break; + + f->data = alloc_symbol_cache(arg + 1, offset); + if (f->data) + f->fn = t->fetch[FETCH_MTD_symbol]; + } + break; + + case '+': /* deref memory */ + arg++; /* Skip '+', because kstrtol() rejects it. */ + case '-': + tmp = strchr(arg, '('); + if (!tmp) + break; + + *tmp = '\0'; + ret = kstrtol(arg, 0, &offset); + + if (ret) + break; + + arg = tmp + 1; + tmp = strrchr(arg, ')'); + + if (tmp) { + struct deref_fetch_param *dprm; + const struct fetch_type *t2; + + t2 = find_fetch_type(NULL, ftbl); + *tmp = '\0'; + dprm = kzalloc(sizeof(struct deref_fetch_param), GFP_KERNEL); + + if (!dprm) + return -ENOMEM; + + dprm->offset = offset; + dprm->fetch = t->fetch[FETCH_MTD_memory]; + dprm->fetch_size = get_fetch_size_function(t, + dprm->fetch, ftbl); + ret = parse_probe_arg(arg, t2, &dprm->orig, is_return, + is_kprobe); + if (ret) + kfree(dprm); + else { + f->fn = t->fetch[FETCH_MTD_deref]; + f->data = (void *)dprm; + } + } + break; + } + if (!ret && !f->fn) { /* Parsed, but do not find fetch method */ + pr_info("%s type has no corresponding fetch method.\n", t->name); + ret = -EINVAL; + } + + return ret; +} + +#define BYTES_TO_BITS(nb) ((BITS_PER_LONG * (nb)) / sizeof(long)) + +/* Bitfield type needs to be parsed into a fetch function */ +static int __parse_bitfield_probe_arg(const char *bf, + const struct fetch_type *t, + struct fetch_param *f) +{ + struct bitfield_fetch_param *bprm; + unsigned long bw, bo; + char *tail; + + if (*bf != 'b') + return 0; + + bprm = kzalloc(sizeof(*bprm), GFP_KERNEL); + if (!bprm) + return -ENOMEM; + + bprm->orig = *f; + f->fn = t->fetch[FETCH_MTD_bitfield]; + f->data = (void *)bprm; + bw = simple_strtoul(bf + 1, &tail, 0); /* Use simple one */ + + if (bw == 0 || *tail != '@') + return -EINVAL; + + bf = tail + 1; + bo = simple_strtoul(bf, &tail, 0); + + if (tail == bf || *tail != '/') + return -EINVAL; + + bprm->hi_shift = BYTES_TO_BITS(t->size) - (bw + bo); + bprm->low_shift = bprm->hi_shift + bo; + + return (BYTES_TO_BITS(t->size) < (bw + bo)) ? -EINVAL : 0; +} + +/* String length checking wrapper */ +int traceprobe_parse_probe_arg(char *arg, ssize_t *size, + struct probe_arg *parg, bool is_return, bool is_kprobe) +{ + const struct fetch_type *ftbl; + const char *t; + int ret; + + ftbl = is_kprobe ? kprobes_fetch_type_table : uprobes_fetch_type_table; + BUG_ON(ftbl == NULL); + + if (strlen(arg) > MAX_ARGSTR_LEN) { + pr_info("Argument is too long.: %s\n", arg); + return -ENOSPC; + } + parg->comm = kstrdup(arg, GFP_KERNEL); + if (!parg->comm) { + pr_info("Failed to allocate memory for command '%s'.\n", arg); + return -ENOMEM; + } + t = strchr(parg->comm, ':'); + if (t) { + arg[t - parg->comm] = '\0'; + t++; + } + parg->type = find_fetch_type(t, ftbl); + if (!parg->type) { + pr_info("Unsupported type: %s\n", t); + return -EINVAL; + } + parg->offset = *size; + *size += parg->type->size; + ret = parse_probe_arg(arg, parg->type, &parg->fetch, is_return, is_kprobe); + + if (ret >= 0 && t != NULL) + ret = __parse_bitfield_probe_arg(t, parg->type, &parg->fetch); + + if (ret >= 0) { + parg->fetch_size.fn = get_fetch_size_function(parg->type, + parg->fetch.fn, + ftbl); + parg->fetch_size.data = parg->fetch.data; + } + + return ret; +} + +/* Return 1 if name is reserved or already used by another argument */ +int traceprobe_conflict_field_name(const char *name, + struct probe_arg *args, int narg) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(reserved_field_names); i++) + if (strcmp(reserved_field_names[i], name) == 0) + return 1; + + for (i = 0; i < narg; i++) + if (strcmp(args[i].name, name) == 0) + return 1; + + return 0; +} + +void traceprobe_update_arg(struct probe_arg *arg) +{ + if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn)) + update_bitfield_fetch_param(arg->fetch.data); + else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn)) + update_deref_fetch_param(arg->fetch.data); + else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn)) + update_symbol_cache(arg->fetch.data); +} + +void traceprobe_free_probe_arg(struct probe_arg *arg) +{ + if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn)) + free_bitfield_fetch_param(arg->fetch.data); + else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn)) + free_deref_fetch_param(arg->fetch.data); + else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn)) + free_symbol_cache(arg->fetch.data); + + kfree(arg->name); + kfree(arg->comm); +} + +int traceprobe_command(const char *buf, int (*createfn)(int, char **)) +{ + char **argv; + int argc, ret; + + argc = 0; + ret = 0; + argv = argv_split(GFP_KERNEL, buf, &argc); + if (!argv) + return -ENOMEM; + + if (argc) + ret = createfn(argc, argv); + + argv_free(argv); + + return ret; +} + +#define WRITE_BUFSIZE 4096 + +ssize_t traceprobe_probes_write(struct file *file, const char __user *buffer, + size_t count, loff_t *ppos, + int (*createfn)(int, char **)) +{ + char *kbuf, *tmp; + int ret = 0; + size_t done = 0; + size_t size; + + kbuf = kmalloc(WRITE_BUFSIZE, GFP_KERNEL); + if (!kbuf) + return -ENOMEM; + + while (done < count) { + size = count - done; + + if (size >= WRITE_BUFSIZE) + size = WRITE_BUFSIZE - 1; + + if (copy_from_user(kbuf, buffer + done, size)) { + ret = -EFAULT; + goto out; + } + kbuf[size] = '\0'; + tmp = strchr(kbuf, '\n'); + + if (tmp) { + *tmp = '\0'; + size = tmp - kbuf + 1; + } else if (done + size < count) { + pr_warning("Line length is too long: " + "Should be less than %d.", WRITE_BUFSIZE); + ret = -EINVAL; + goto out; + } + done += size; + /* Remove comments */ + tmp = strchr(kbuf, '#'); + + if (tmp) + *tmp = '\0'; + + ret = traceprobe_command(kbuf, createfn); + if (ret) + goto out; + } + ret = done; + +out: + kfree(kbuf); + + return ret; +} + +static int __set_print_fmt(struct trace_probe *tp, char *buf, int len, + bool is_return) +{ + int i; + int pos = 0; + + const char *fmt, *arg; + + if (!is_return) { + fmt = "(%lx)"; + arg = "REC->" FIELD_STRING_IP; + } else { + fmt = "(%lx <- %lx)"; + arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP; + } + + /* When len=0, we just calculate the needed length */ +#define LEN_OR_ZERO (len ? len - pos : 0) + + pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt); + + for (i = 0; i < tp->nr_args; i++) { + pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s", + tp->args[i].name, tp->args[i].type->fmt); + } + + pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg); + + for (i = 0; i < tp->nr_args; i++) { + if (strcmp(tp->args[i].type->name, "string") == 0) + pos += snprintf(buf + pos, LEN_OR_ZERO, + ", __get_str(%s)", + tp->args[i].name); + else + pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s", + tp->args[i].name); + } + +#undef LEN_OR_ZERO + + /* return the length of print_fmt */ + return pos; +} + +int set_print_fmt(struct trace_probe *tp, bool is_return) +{ + int len; + char *print_fmt; + + /* First: called with 0 length to calculate the needed length */ + len = __set_print_fmt(tp, NULL, 0, is_return); + print_fmt = kmalloc(len + 1, GFP_KERNEL); + if (!print_fmt) + return -ENOMEM; + + /* Second: actually write the @print_fmt */ + __set_print_fmt(tp, print_fmt, len + 1, is_return); + tp->call.print_fmt = print_fmt; + + return 0; +} diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h new file mode 100644 index 00000000000..4f815fbce16 --- /dev/null +++ b/kernel/trace/trace_probe.h @@ -0,0 +1,400 @@ +/* + * Common header file for probe-based Dynamic events. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * This code was copied from kernel/trace/trace_kprobe.h written by + * Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> + * + * Updates to make this generic: + * Copyright (C) IBM Corporation, 2010-2011 + * Author: Srikar Dronamraju + */ + +#include <linux/seq_file.h> +#include <linux/slab.h> +#include <linux/smp.h> +#include <linux/debugfs.h> +#include <linux/types.h> +#include <linux/string.h> +#include <linux/ctype.h> +#include <linux/ptrace.h> +#include <linux/perf_event.h> +#include <linux/kprobes.h> +#include <linux/stringify.h> +#include <linux/limits.h> +#include <linux/uaccess.h> +#include <asm/bitsperlong.h> + +#include "trace.h" +#include "trace_output.h" + +#define MAX_TRACE_ARGS 128 +#define MAX_ARGSTR_LEN 63 +#define MAX_EVENT_NAME_LEN 64 +#define MAX_STRING_SIZE PATH_MAX + +/* Reserved field names */ +#define FIELD_STRING_IP "__probe_ip" +#define FIELD_STRING_RETIP "__probe_ret_ip" +#define FIELD_STRING_FUNC "__probe_func" + +#undef DEFINE_FIELD +#define DEFINE_FIELD(type, item, name, is_signed) \ + do { \ + ret = trace_define_field(event_call, #type, name, \ + offsetof(typeof(field), item), \ + sizeof(field.item), is_signed, \ + FILTER_OTHER); \ + if (ret) \ + return ret; \ + } while (0) + + +/* Flags for trace_probe */ +#define TP_FLAG_TRACE 1 +#define TP_FLAG_PROFILE 2 +#define TP_FLAG_REGISTERED 4 + + +/* data_rloc: data relative location, compatible with u32 */ +#define make_data_rloc(len, roffs) \ + (((u32)(len) << 16) | ((u32)(roffs) & 0xffff)) +#define get_rloc_len(dl) ((u32)(dl) >> 16) +#define get_rloc_offs(dl) ((u32)(dl) & 0xffff) + +/* + * Convert data_rloc to data_loc: + * data_rloc stores the offset from data_rloc itself, but data_loc + * stores the offset from event entry. + */ +#define convert_rloc_to_loc(dl, offs) ((u32)(dl) + (offs)) + +static nokprobe_inline void *get_rloc_data(u32 *dl) +{ + return (u8 *)dl + get_rloc_offs(*dl); +} + +/* For data_loc conversion */ +static nokprobe_inline void *get_loc_data(u32 *dl, void *ent) +{ + return (u8 *)ent + get_rloc_offs(*dl); +} + +/* Data fetch function type */ +typedef void (*fetch_func_t)(struct pt_regs *, void *, void *); +/* Printing function type */ +typedef int (*print_type_func_t)(struct trace_seq *, const char *, void *, void *); + +/* Fetch types */ +enum { + FETCH_MTD_reg = 0, + FETCH_MTD_stack, + FETCH_MTD_retval, + FETCH_MTD_memory, + FETCH_MTD_symbol, + FETCH_MTD_deref, + FETCH_MTD_bitfield, + FETCH_MTD_file_offset, + FETCH_MTD_END, +}; + +/* Fetch type information table */ +struct fetch_type { + const char *name; /* Name of type */ + size_t size; /* Byte size of type */ + int is_signed; /* Signed flag */ + print_type_func_t print; /* Print functions */ + const char *fmt; /* Fromat string */ + const char *fmttype; /* Name in format file */ + /* Fetch functions */ + fetch_func_t fetch[FETCH_MTD_END]; +}; + +struct fetch_param { + fetch_func_t fn; + void *data; +}; + +/* For defining macros, define string/string_size types */ +typedef u32 string; +typedef u32 string_size; + +#define PRINT_TYPE_FUNC_NAME(type) print_type_##type +#define PRINT_TYPE_FMT_NAME(type) print_type_format_##type + +/* Printing in basic type function template */ +#define DECLARE_BASIC_PRINT_TYPE_FUNC(type) \ +int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, const char *name, \ + void *data, void *ent); \ +extern const char PRINT_TYPE_FMT_NAME(type)[] + +DECLARE_BASIC_PRINT_TYPE_FUNC(u8); +DECLARE_BASIC_PRINT_TYPE_FUNC(u16); +DECLARE_BASIC_PRINT_TYPE_FUNC(u32); +DECLARE_BASIC_PRINT_TYPE_FUNC(u64); +DECLARE_BASIC_PRINT_TYPE_FUNC(s8); +DECLARE_BASIC_PRINT_TYPE_FUNC(s16); +DECLARE_BASIC_PRINT_TYPE_FUNC(s32); +DECLARE_BASIC_PRINT_TYPE_FUNC(s64); +DECLARE_BASIC_PRINT_TYPE_FUNC(string); + +#define FETCH_FUNC_NAME(method, type) fetch_##method##_##type + +/* Declare macro for basic types */ +#define DECLARE_FETCH_FUNC(method, type) \ +extern void FETCH_FUNC_NAME(method, type)(struct pt_regs *regs, \ + void *data, void *dest) + +#define DECLARE_BASIC_FETCH_FUNCS(method) \ +DECLARE_FETCH_FUNC(method, u8); \ +DECLARE_FETCH_FUNC(method, u16); \ +DECLARE_FETCH_FUNC(method, u32); \ +DECLARE_FETCH_FUNC(method, u64) + +DECLARE_BASIC_FETCH_FUNCS(reg); +#define fetch_reg_string NULL +#define fetch_reg_string_size NULL + +DECLARE_BASIC_FETCH_FUNCS(retval); +#define fetch_retval_string NULL +#define fetch_retval_string_size NULL + +DECLARE_BASIC_FETCH_FUNCS(symbol); +DECLARE_FETCH_FUNC(symbol, string); +DECLARE_FETCH_FUNC(symbol, string_size); + +DECLARE_BASIC_FETCH_FUNCS(deref); +DECLARE_FETCH_FUNC(deref, string); +DECLARE_FETCH_FUNC(deref, string_size); + +DECLARE_BASIC_FETCH_FUNCS(bitfield); +#define fetch_bitfield_string NULL +#define fetch_bitfield_string_size NULL + +/* + * Define macro for basic types - we don't need to define s* types, because + * we have to care only about bitwidth at recording time. + */ +#define DEFINE_BASIC_FETCH_FUNCS(method) \ +DEFINE_FETCH_##method(u8) \ +DEFINE_FETCH_##method(u16) \ +DEFINE_FETCH_##method(u32) \ +DEFINE_FETCH_##method(u64) + +/* Default (unsigned long) fetch type */ +#define __DEFAULT_FETCH_TYPE(t) u##t +#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t) +#define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG) +#define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE) + +#define ASSIGN_FETCH_FUNC(method, type) \ + [FETCH_MTD_##method] = FETCH_FUNC_NAME(method, type) + +#define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \ + {.name = _name, \ + .size = _size, \ + .is_signed = sign, \ + .print = PRINT_TYPE_FUNC_NAME(ptype), \ + .fmt = PRINT_TYPE_FMT_NAME(ptype), \ + .fmttype = _fmttype, \ + .fetch = { \ +ASSIGN_FETCH_FUNC(reg, ftype), \ +ASSIGN_FETCH_FUNC(stack, ftype), \ +ASSIGN_FETCH_FUNC(retval, ftype), \ +ASSIGN_FETCH_FUNC(memory, ftype), \ +ASSIGN_FETCH_FUNC(symbol, ftype), \ +ASSIGN_FETCH_FUNC(deref, ftype), \ +ASSIGN_FETCH_FUNC(bitfield, ftype), \ +ASSIGN_FETCH_FUNC(file_offset, ftype), \ + } \ + } + +#define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \ + __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype) + +#define ASSIGN_FETCH_TYPE_END {} + +#define FETCH_TYPE_STRING 0 +#define FETCH_TYPE_STRSIZE 1 + +/* + * Fetch type information table. + * It's declared as a weak symbol due to conditional compilation. + */ +extern __weak const struct fetch_type kprobes_fetch_type_table[]; +extern __weak const struct fetch_type uprobes_fetch_type_table[]; + +#ifdef CONFIG_KPROBE_EVENT +struct symbol_cache; +unsigned long update_symbol_cache(struct symbol_cache *sc); +void free_symbol_cache(struct symbol_cache *sc); +struct symbol_cache *alloc_symbol_cache(const char *sym, long offset); +#else +/* uprobes do not support symbol fetch methods */ +#define fetch_symbol_u8 NULL +#define fetch_symbol_u16 NULL +#define fetch_symbol_u32 NULL +#define fetch_symbol_u64 NULL +#define fetch_symbol_string NULL +#define fetch_symbol_string_size NULL + +struct symbol_cache { +}; +static inline unsigned long __used update_symbol_cache(struct symbol_cache *sc) +{ + return 0; +} + +static inline void __used free_symbol_cache(struct symbol_cache *sc) +{ +} + +static inline struct symbol_cache * __used +alloc_symbol_cache(const char *sym, long offset) +{ + return NULL; +} +#endif /* CONFIG_KPROBE_EVENT */ + +struct probe_arg { + struct fetch_param fetch; + struct fetch_param fetch_size; + unsigned int offset; /* Offset from argument entry */ + const char *name; /* Name of this argument */ + const char *comm; /* Command of this argument */ + const struct fetch_type *type; /* Type of this argument */ +}; + +struct trace_probe { + unsigned int flags; /* For TP_FLAG_* */ + struct ftrace_event_class class; + struct ftrace_event_call call; + struct list_head files; + ssize_t size; /* trace entry size */ + unsigned int nr_args; + struct probe_arg args[]; +}; + +struct event_file_link { + struct ftrace_event_file *file; + struct list_head list; +}; + +static inline bool trace_probe_is_enabled(struct trace_probe *tp) +{ + return !!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE)); +} + +static inline bool trace_probe_is_registered(struct trace_probe *tp) +{ + return !!(tp->flags & TP_FLAG_REGISTERED); +} + +static nokprobe_inline void call_fetch(struct fetch_param *fprm, + struct pt_regs *regs, void *dest) +{ + return fprm->fn(regs, fprm->data, dest); +} + +/* Check the name is good for event/group/fields */ +static inline int is_good_name(const char *name) +{ + if (!isalpha(*name) && *name != '_') + return 0; + while (*++name != '\0') { + if (!isalpha(*name) && !isdigit(*name) && *name != '_') + return 0; + } + return 1; +} + +static inline struct event_file_link * +find_event_file_link(struct trace_probe *tp, struct ftrace_event_file *file) +{ + struct event_file_link *link; + + list_for_each_entry(link, &tp->files, list) + if (link->file == file) + return link; + + return NULL; +} + +extern int traceprobe_parse_probe_arg(char *arg, ssize_t *size, + struct probe_arg *parg, bool is_return, bool is_kprobe); + +extern int traceprobe_conflict_field_name(const char *name, + struct probe_arg *args, int narg); + +extern void traceprobe_update_arg(struct probe_arg *arg); +extern void traceprobe_free_probe_arg(struct probe_arg *arg); + +extern int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset); + +extern ssize_t traceprobe_probes_write(struct file *file, + const char __user *buffer, size_t count, loff_t *ppos, + int (*createfn)(int, char**)); + +extern int traceprobe_command(const char *buf, int (*createfn)(int, char**)); + +/* Sum up total data length for dynamic arraies (strings) */ +static nokprobe_inline int +__get_data_size(struct trace_probe *tp, struct pt_regs *regs) +{ + int i, ret = 0; + u32 len; + + for (i = 0; i < tp->nr_args; i++) + if (unlikely(tp->args[i].fetch_size.fn)) { + call_fetch(&tp->args[i].fetch_size, regs, &len); + ret += len; + } + + return ret; +} + +/* Store the value of each argument */ +static nokprobe_inline void +store_trace_args(int ent_size, struct trace_probe *tp, struct pt_regs *regs, + u8 *data, int maxlen) +{ + int i; + u32 end = tp->size; + u32 *dl; /* Data (relative) location */ + + for (i = 0; i < tp->nr_args; i++) { + if (unlikely(tp->args[i].fetch_size.fn)) { + /* + * First, we set the relative location and + * maximum data length to *dl + */ + dl = (u32 *)(data + tp->args[i].offset); + *dl = make_data_rloc(maxlen, end - tp->args[i].offset); + /* Then try to fetch string or dynamic array data */ + call_fetch(&tp->args[i].fetch, regs, dl); + /* Reduce maximum length */ + end += get_rloc_len(*dl); + maxlen -= get_rloc_len(*dl); + /* Trick here, convert data_rloc to data_loc */ + *dl = convert_rloc_to_loc(*dl, + ent_size + tp->args[i].offset); + } else + /* Just fetching data normally */ + call_fetch(&tp->args[i].fetch, regs, + data + tp->args[i].offset); + } +} + +extern int set_print_fmt(struct trace_probe *tp, bool is_return); diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c index a98106dd979..3f34dc9b40f 100644 --- a/kernel/trace/trace_sched_switch.c +++ b/kernel/trace/trace_sched_switch.c @@ -20,9 +20,37 @@ static int sched_ref; static DEFINE_MUTEX(sched_register_mutex); static int sched_stopped; + +void +tracing_sched_switch_trace(struct trace_array *tr, + struct task_struct *prev, + struct task_struct *next, + unsigned long flags, int pc) +{ + struct ftrace_event_call *call = &event_context_switch; + struct ring_buffer *buffer = tr->trace_buffer.buffer; + struct ring_buffer_event *event; + struct ctx_switch_entry *entry; + + event = trace_buffer_lock_reserve(buffer, TRACE_CTX, + sizeof(*entry), flags, pc); + if (!event) + return; + entry = ring_buffer_event_data(event); + entry->prev_pid = prev->pid; + entry->prev_prio = prev->prio; + entry->prev_state = prev->state; + entry->next_pid = next->pid; + entry->next_prio = next->prio; + entry->next_state = next->state; + entry->next_cpu = task_cpu(next); + + if (!call_filter_check_discard(call, entry, buffer, event)) + trace_buffer_unlock_commit(buffer, event, flags, pc); +} + static void -probe_sched_switch(struct rq *__rq, struct task_struct *prev, - struct task_struct *next) +probe_sched_switch(void *ignore, struct task_struct *prev, struct task_struct *next) { struct trace_array_cpu *data; unsigned long flags; @@ -41,7 +69,7 @@ probe_sched_switch(struct rq *__rq, struct task_struct *prev, pc = preempt_count(); local_irq_save(flags); cpu = raw_smp_processor_id(); - data = ctx_trace->data[cpu]; + data = per_cpu_ptr(ctx_trace->trace_buffer.data, cpu); if (likely(!atomic_read(&data->disabled))) tracing_sched_switch_trace(ctx_trace, prev, next, flags, pc); @@ -49,8 +77,36 @@ probe_sched_switch(struct rq *__rq, struct task_struct *prev, local_irq_restore(flags); } +void +tracing_sched_wakeup_trace(struct trace_array *tr, + struct task_struct *wakee, + struct task_struct *curr, + unsigned long flags, int pc) +{ + struct ftrace_event_call *call = &event_wakeup; + struct ring_buffer_event *event; + struct ctx_switch_entry *entry; + struct ring_buffer *buffer = tr->trace_buffer.buffer; + + event = trace_buffer_lock_reserve(buffer, TRACE_WAKE, + sizeof(*entry), flags, pc); + if (!event) + return; + entry = ring_buffer_event_data(event); + entry->prev_pid = curr->pid; + entry->prev_prio = curr->prio; + entry->prev_state = curr->state; + entry->next_pid = wakee->pid; + entry->next_prio = wakee->prio; + entry->next_state = wakee->state; + entry->next_cpu = task_cpu(wakee); + + if (!call_filter_check_discard(call, entry, buffer, event)) + trace_buffer_unlock_commit(buffer, event, flags, pc); +} + static void -probe_sched_wakeup(struct rq *__rq, struct task_struct *wakee, int success) +probe_sched_wakeup(void *ignore, struct task_struct *wakee, int success) { struct trace_array_cpu *data; unsigned long flags; @@ -67,7 +123,7 @@ probe_sched_wakeup(struct rq *__rq, struct task_struct *wakee, int success) pc = preempt_count(); local_irq_save(flags); cpu = raw_smp_processor_id(); - data = ctx_trace->data[cpu]; + data = per_cpu_ptr(ctx_trace->trace_buffer.data, cpu); if (likely(!atomic_read(&data->disabled))) tracing_sched_wakeup_trace(ctx_trace, wakee, current, @@ -80,21 +136,21 @@ static int tracing_sched_register(void) { int ret; - ret = register_trace_sched_wakeup(probe_sched_wakeup); + ret = register_trace_sched_wakeup(probe_sched_wakeup, NULL); if (ret) { pr_info("wakeup trace: Couldn't activate tracepoint" " probe to kernel_sched_wakeup\n"); return ret; } - ret = register_trace_sched_wakeup_new(probe_sched_wakeup); + ret = register_trace_sched_wakeup_new(probe_sched_wakeup, NULL); if (ret) { pr_info("wakeup trace: Couldn't activate tracepoint" " probe to kernel_sched_wakeup_new\n"); goto fail_deprobe; } - ret = register_trace_sched_switch(probe_sched_switch); + ret = register_trace_sched_switch(probe_sched_switch, NULL); if (ret) { pr_info("sched trace: Couldn't activate tracepoint" " probe to kernel_sched_switch\n"); @@ -103,17 +159,17 @@ static int tracing_sched_register(void) return ret; fail_deprobe_wake_new: - unregister_trace_sched_wakeup_new(probe_sched_wakeup); + unregister_trace_sched_wakeup_new(probe_sched_wakeup, NULL); fail_deprobe: - unregister_trace_sched_wakeup(probe_sched_wakeup); + unregister_trace_sched_wakeup(probe_sched_wakeup, NULL); return ret; } static void tracing_sched_unregister(void) { - unregister_trace_sched_switch(probe_sched_switch); - unregister_trace_sched_wakeup_new(probe_sched_wakeup); - unregister_trace_sched_wakeup(probe_sched_wakeup); + unregister_trace_sched_switch(probe_sched_switch, NULL); + unregister_trace_sched_wakeup_new(probe_sched_wakeup, NULL); + unregister_trace_sched_wakeup(probe_sched_wakeup, NULL); } static void tracing_start_sched_switch(void) @@ -189,51 +245,3 @@ void tracing_sched_switch_assign_trace(struct trace_array *tr) ctx_trace = tr; } -static void stop_sched_trace(struct trace_array *tr) -{ - tracing_stop_sched_switch_record(); -} - -static int sched_switch_trace_init(struct trace_array *tr) -{ - ctx_trace = tr; - tracing_reset_online_cpus(tr); - tracing_start_sched_switch_record(); - return 0; -} - -static void sched_switch_trace_reset(struct trace_array *tr) -{ - if (sched_ref) - stop_sched_trace(tr); -} - -static void sched_switch_trace_start(struct trace_array *tr) -{ - sched_stopped = 0; -} - -static void sched_switch_trace_stop(struct trace_array *tr) -{ - sched_stopped = 1; -} - -static struct tracer sched_switch_trace __read_mostly = -{ - .name = "sched_switch", - .init = sched_switch_trace_init, - .reset = sched_switch_trace_reset, - .start = sched_switch_trace_start, - .stop = sched_switch_trace_stop, - .wait_pipe = poll_wait_pipe, -#ifdef CONFIG_FTRACE_SELFTEST - .selftest = trace_selftest_startup_sched_switch, -#endif -}; - -__init static int init_sched_switch_trace(void) -{ - return register_tracer(&sched_switch_trace); -} -device_initcall(init_sched_switch_trace); - diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c index eacb2722517..19bd8928ce9 100644 --- a/kernel/trace/trace_sched_wakeup.c +++ b/kernel/trace/trace_sched_wakeup.c @@ -7,7 +7,7 @@ * Based on code from the latency_tracer, that is: * * Copyright (C) 2004-2006 Ingo Molnar - * Copyright (C) 2004 William Lee Irwin III + * Copyright (C) 2004 Nadia Yvette Chambers */ #include <linux/module.h> #include <linux/fs.h> @@ -15,8 +15,9 @@ #include <linux/kallsyms.h> #include <linux/uaccess.h> #include <linux/ftrace.h> +#include <linux/sched/rt.h> +#include <linux/sched/deadline.h> #include <trace/events/sched.h> - #include "trace.h" static struct trace_array *wakeup_trace; @@ -24,94 +25,350 @@ static int __read_mostly tracer_enabled; static struct task_struct *wakeup_task; static int wakeup_cpu; +static int wakeup_current_cpu; static unsigned wakeup_prio = -1; static int wakeup_rt; +static int wakeup_dl; +static int tracing_dl = 0; -static raw_spinlock_t wakeup_lock = - (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; +static arch_spinlock_t wakeup_lock = + (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; +static void wakeup_reset(struct trace_array *tr); static void __wakeup_reset(struct trace_array *tr); +static int wakeup_graph_entry(struct ftrace_graph_ent *trace); +static void wakeup_graph_return(struct ftrace_graph_ret *trace); + +static int save_flags; +static bool function_enabled; -static int save_lat_flag; +#define TRACE_DISPLAY_GRAPH 1 + +static struct tracer_opt trace_opts[] = { +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + /* display latency trace as call graph */ + { TRACER_OPT(display-graph, TRACE_DISPLAY_GRAPH) }, +#endif + { } /* Empty entry */ +}; + +static struct tracer_flags tracer_flags = { + .val = 0, + .opts = trace_opts, +}; + +#define is_graph() (tracer_flags.val & TRACE_DISPLAY_GRAPH) #ifdef CONFIG_FUNCTION_TRACER + /* - * irqsoff uses its own tracer function to keep the overhead down: + * Prologue for the wakeup function tracers. + * + * Returns 1 if it is OK to continue, and preemption + * is disabled and data->disabled is incremented. + * 0 if the trace is to be ignored, and preemption + * is not disabled and data->disabled is + * kept the same. + * + * Note, this function is also used outside this ifdef but + * inside the #ifdef of the function graph tracer below. + * This is OK, since the function graph tracer is + * dependent on the function tracer. */ -static void -wakeup_tracer_call(unsigned long ip, unsigned long parent_ip) +static int +func_prolog_preempt_disable(struct trace_array *tr, + struct trace_array_cpu **data, + int *pc) { - struct trace_array *tr = wakeup_trace; - struct trace_array_cpu *data; - unsigned long flags; long disabled; - int resched; int cpu; - int pc; if (likely(!wakeup_task)) - return; + return 0; - pc = preempt_count(); - resched = ftrace_preempt_disable(); + *pc = preempt_count(); + preempt_disable_notrace(); cpu = raw_smp_processor_id(); - data = tr->data[cpu]; - disabled = atomic_inc_return(&data->disabled); + if (cpu != wakeup_current_cpu) + goto out_enable; + + *data = per_cpu_ptr(tr->trace_buffer.data, cpu); + disabled = atomic_inc_return(&(*data)->disabled); if (unlikely(disabled != 1)) goto out; + return 1; + +out: + atomic_dec(&(*data)->disabled); + +out_enable: + preempt_enable_notrace(); + return 0; +} + +/* + * wakeup uses its own tracer function to keep the overhead down: + */ +static void +wakeup_tracer_call(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct pt_regs *pt_regs) +{ + struct trace_array *tr = wakeup_trace; + struct trace_array_cpu *data; + unsigned long flags; + int pc; + + if (!func_prolog_preempt_disable(tr, &data, &pc)) + return; + local_irq_save(flags); - __raw_spin_lock(&wakeup_lock); + trace_function(tr, ip, parent_ip, flags, pc); + local_irq_restore(flags); - if (unlikely(!wakeup_task)) - goto unlock; + atomic_dec(&data->disabled); + preempt_enable_notrace(); +} +#endif /* CONFIG_FUNCTION_TRACER */ + +static int register_wakeup_function(struct trace_array *tr, int graph, int set) +{ + int ret; + + /* 'set' is set if TRACE_ITER_FUNCTION is about to be set */ + if (function_enabled || (!set && !(trace_flags & TRACE_ITER_FUNCTION))) + return 0; + + if (graph) + ret = register_ftrace_graph(&wakeup_graph_return, + &wakeup_graph_entry); + else + ret = register_ftrace_function(tr->ops); + + if (!ret) + function_enabled = true; + + return ret; +} + +static void unregister_wakeup_function(struct trace_array *tr, int graph) +{ + if (!function_enabled) + return; + + if (graph) + unregister_ftrace_graph(); + else + unregister_ftrace_function(tr->ops); + + function_enabled = false; +} + +static void wakeup_function_set(struct trace_array *tr, int set) +{ + if (set) + register_wakeup_function(tr, is_graph(), 1); + else + unregister_wakeup_function(tr, is_graph()); +} + +static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set) +{ + struct tracer *tracer = tr->current_trace; + + if (mask & TRACE_ITER_FUNCTION) + wakeup_function_set(tr, set); + + return trace_keep_overwrite(tracer, mask, set); +} + +static int start_func_tracer(struct trace_array *tr, int graph) +{ + int ret; + + ret = register_wakeup_function(tr, graph, 0); + + if (!ret && tracing_is_enabled()) + tracer_enabled = 1; + else + tracer_enabled = 0; + + return ret; +} + +static void stop_func_tracer(struct trace_array *tr, int graph) +{ + tracer_enabled = 0; + + unregister_wakeup_function(tr, graph); +} + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +static int +wakeup_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) +{ + + if (!(bit & TRACE_DISPLAY_GRAPH)) + return -EINVAL; + + if (!(is_graph() ^ set)) + return 0; + + stop_func_tracer(tr, !set); + + wakeup_reset(wakeup_trace); + tr->max_latency = 0; + + return start_func_tracer(tr, set); +} + +static int wakeup_graph_entry(struct ftrace_graph_ent *trace) +{ + struct trace_array *tr = wakeup_trace; + struct trace_array_cpu *data; + unsigned long flags; + int pc, ret = 0; + + if (!func_prolog_preempt_disable(tr, &data, &pc)) + return 0; + + local_save_flags(flags); + ret = __trace_graph_entry(tr, trace, flags, pc); + atomic_dec(&data->disabled); + preempt_enable_notrace(); + + return ret; +} +static void wakeup_graph_return(struct ftrace_graph_ret *trace) +{ + struct trace_array *tr = wakeup_trace; + struct trace_array_cpu *data; + unsigned long flags; + int pc; + + if (!func_prolog_preempt_disable(tr, &data, &pc)) + return; + + local_save_flags(flags); + __trace_graph_return(tr, trace, flags, pc); + atomic_dec(&data->disabled); + + preempt_enable_notrace(); + return; +} + +static void wakeup_trace_open(struct trace_iterator *iter) +{ + if (is_graph()) + graph_trace_open(iter); +} + +static void wakeup_trace_close(struct trace_iterator *iter) +{ + if (iter->private) + graph_trace_close(iter); +} + +#define GRAPH_TRACER_FLAGS (TRACE_GRAPH_PRINT_PROC | \ + TRACE_GRAPH_PRINT_ABS_TIME | \ + TRACE_GRAPH_PRINT_DURATION) + +static enum print_line_t wakeup_print_line(struct trace_iterator *iter) +{ /* - * The task can't disappear because it needs to - * wake up first, and we have the wakeup_lock. + * In graph mode call the graph tracer output function, + * otherwise go with the TRACE_FN event handler */ - if (task_cpu(wakeup_task) != cpu) - goto unlock; + if (is_graph()) + return print_graph_function_flags(iter, GRAPH_TRACER_FLAGS); - trace_function(tr, ip, parent_ip, flags, pc); + return TRACE_TYPE_UNHANDLED; +} - unlock: - __raw_spin_unlock(&wakeup_lock); - local_irq_restore(flags); +static void wakeup_print_header(struct seq_file *s) +{ + if (is_graph()) + print_graph_headers_flags(s, GRAPH_TRACER_FLAGS); + else + trace_default_header(s); +} - out: - atomic_dec(&data->disabled); +static void +__trace_function(struct trace_array *tr, + unsigned long ip, unsigned long parent_ip, + unsigned long flags, int pc) +{ + if (is_graph()) + trace_graph_function(tr, ip, parent_ip, flags, pc); + else + trace_function(tr, ip, parent_ip, flags, pc); +} +#else +#define __trace_function trace_function - ftrace_preempt_enable(resched); +static int +wakeup_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) +{ + return -EINVAL; } -static struct ftrace_ops trace_ops __read_mostly = +static int wakeup_graph_entry(struct ftrace_graph_ent *trace) { - .func = wakeup_tracer_call, -}; + return -1; +} + +static enum print_line_t wakeup_print_line(struct trace_iterator *iter) +{ + return TRACE_TYPE_UNHANDLED; +} + +static void wakeup_graph_return(struct ftrace_graph_ret *trace) { } +static void wakeup_trace_open(struct trace_iterator *iter) { } +static void wakeup_trace_close(struct trace_iterator *iter) { } + +#ifdef CONFIG_FUNCTION_TRACER +static void wakeup_print_header(struct seq_file *s) +{ + trace_default_header(s); +} +#else +static void wakeup_print_header(struct seq_file *s) +{ + trace_latency_header(s); +} #endif /* CONFIG_FUNCTION_TRACER */ +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ /* * Should this new latency be reported/recorded? */ -static int report_latency(cycle_t delta) +static int report_latency(struct trace_array *tr, cycle_t delta) { if (tracing_thresh) { if (delta < tracing_thresh) return 0; } else { - if (delta <= tracing_max_latency) + if (delta <= tr->max_latency) return 0; } return 1; } +static void +probe_wakeup_migrate_task(void *ignore, struct task_struct *task, int cpu) +{ + if (task != wakeup_task) + return; + + wakeup_current_cpu = cpu; +} + static void notrace -probe_wakeup_sched_switch(struct rq *rq, struct task_struct *prev, - struct task_struct *next) +probe_wakeup_sched_switch(void *ignore, + struct task_struct *prev, struct task_struct *next) { - unsigned long latency = 0, t0 = 0, t1 = 0; struct trace_array_cpu *data; cycle_t T0, T1, delta; unsigned long flags; @@ -140,59 +397,48 @@ probe_wakeup_sched_switch(struct rq *rq, struct task_struct *prev, /* disable local data, not wakeup_cpu data */ cpu = raw_smp_processor_id(); - disabled = atomic_inc_return(&wakeup_trace->data[cpu]->disabled); + disabled = atomic_inc_return(&per_cpu_ptr(wakeup_trace->trace_buffer.data, cpu)->disabled); if (likely(disabled != 1)) goto out; local_irq_save(flags); - __raw_spin_lock(&wakeup_lock); + arch_spin_lock(&wakeup_lock); /* We could race with grabbing wakeup_lock */ if (unlikely(!tracer_enabled || next != wakeup_task)) goto out_unlock; /* The task we are waiting for is waking up */ - data = wakeup_trace->data[wakeup_cpu]; + data = per_cpu_ptr(wakeup_trace->trace_buffer.data, wakeup_cpu); - trace_function(wakeup_trace, CALLER_ADDR0, CALLER_ADDR1, flags, pc); + __trace_function(wakeup_trace, CALLER_ADDR0, CALLER_ADDR1, flags, pc); tracing_sched_switch_trace(wakeup_trace, prev, next, flags, pc); - /* - * usecs conversion is slow so we try to delay the conversion - * as long as possible: - */ T0 = data->preempt_timestamp; T1 = ftrace_now(cpu); delta = T1-T0; - if (!report_latency(delta)) + if (!report_latency(wakeup_trace, delta)) goto out_unlock; - latency = nsecs_to_usecs(delta); - - tracing_max_latency = delta; - t0 = nsecs_to_usecs(T0); - t1 = nsecs_to_usecs(T1); - - update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu); + if (likely(!is_tracing_stopped())) { + wakeup_trace->max_latency = delta; + update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu); + } out_unlock: __wakeup_reset(wakeup_trace); - __raw_spin_unlock(&wakeup_lock); + arch_spin_unlock(&wakeup_lock); local_irq_restore(flags); out: - atomic_dec(&wakeup_trace->data[cpu]->disabled); + atomic_dec(&per_cpu_ptr(wakeup_trace->trace_buffer.data, cpu)->disabled); } static void __wakeup_reset(struct trace_array *tr) { - int cpu; - - for_each_possible_cpu(cpu) - tracing_reset(tr, cpu); - wakeup_cpu = -1; wakeup_prio = -1; + tracing_dl = 0; if (wakeup_task) put_task_struct(wakeup_task); @@ -204,15 +450,17 @@ static void wakeup_reset(struct trace_array *tr) { unsigned long flags; + tracing_reset_online_cpus(&tr->trace_buffer); + local_irq_save(flags); - __raw_spin_lock(&wakeup_lock); + arch_spin_lock(&wakeup_lock); __wakeup_reset(tr); - __raw_spin_unlock(&wakeup_lock); + arch_spin_unlock(&wakeup_lock); local_irq_restore(flags); } static void -probe_wakeup(struct rq *rq, struct task_struct *p, int success) +probe_wakeup(void *ignore, struct task_struct *p, int success) { struct trace_array_cpu *data; int cpu = smp_processor_id(); @@ -226,35 +474,54 @@ probe_wakeup(struct rq *rq, struct task_struct *p, int success) tracing_record_cmdline(p); tracing_record_cmdline(current); - if ((wakeup_rt && !rt_task(p)) || - p->prio >= wakeup_prio || - p->prio >= current->prio) + /* + * Semantic is like this: + * - wakeup tracer handles all tasks in the system, independently + * from their scheduling class; + * - wakeup_rt tracer handles tasks belonging to sched_dl and + * sched_rt class; + * - wakeup_dl handles tasks belonging to sched_dl class only. + */ + if (tracing_dl || (wakeup_dl && !dl_task(p)) || + (wakeup_rt && !dl_task(p) && !rt_task(p)) || + (!dl_task(p) && (p->prio >= wakeup_prio || p->prio >= current->prio))) return; pc = preempt_count(); - disabled = atomic_inc_return(&wakeup_trace->data[cpu]->disabled); + disabled = atomic_inc_return(&per_cpu_ptr(wakeup_trace->trace_buffer.data, cpu)->disabled); if (unlikely(disabled != 1)) goto out; /* interrupts should be off from try_to_wake_up */ - __raw_spin_lock(&wakeup_lock); + arch_spin_lock(&wakeup_lock); /* check for races. */ - if (!tracer_enabled || p->prio >= wakeup_prio) + if (!tracer_enabled || tracing_dl || + (!dl_task(p) && p->prio >= wakeup_prio)) goto out_locked; /* reset the trace */ __wakeup_reset(wakeup_trace); wakeup_cpu = task_cpu(p); + wakeup_current_cpu = wakeup_cpu; wakeup_prio = p->prio; + /* + * Once you start tracing a -deadline task, don't bother tracing + * another task until the first one wakes up. + */ + if (dl_task(p)) + tracing_dl = 1; + else + tracing_dl = 0; + wakeup_task = p; get_task_struct(wakeup_task); local_save_flags(flags); - data = wakeup_trace->data[wakeup_cpu]; + data = per_cpu_ptr(wakeup_trace->trace_buffer.data, wakeup_cpu); data->preempt_timestamp = ftrace_now(cpu); tracing_sched_wakeup_trace(wakeup_trace, p, current, flags, pc); @@ -263,39 +530,46 @@ probe_wakeup(struct rq *rq, struct task_struct *p, int success) * is not called by an assembly function (where as schedule is) * it should be safe to use it here. */ - trace_function(wakeup_trace, CALLER_ADDR1, CALLER_ADDR2, flags, pc); + __trace_function(wakeup_trace, CALLER_ADDR1, CALLER_ADDR2, flags, pc); out_locked: - __raw_spin_unlock(&wakeup_lock); + arch_spin_unlock(&wakeup_lock); out: - atomic_dec(&wakeup_trace->data[cpu]->disabled); + atomic_dec(&per_cpu_ptr(wakeup_trace->trace_buffer.data, cpu)->disabled); } static void start_wakeup_tracer(struct trace_array *tr) { int ret; - ret = register_trace_sched_wakeup(probe_wakeup); + ret = register_trace_sched_wakeup(probe_wakeup, NULL); if (ret) { pr_info("wakeup trace: Couldn't activate tracepoint" " probe to kernel_sched_wakeup\n"); return; } - ret = register_trace_sched_wakeup_new(probe_wakeup); + ret = register_trace_sched_wakeup_new(probe_wakeup, NULL); if (ret) { pr_info("wakeup trace: Couldn't activate tracepoint" " probe to kernel_sched_wakeup_new\n"); goto fail_deprobe; } - ret = register_trace_sched_switch(probe_wakeup_sched_switch); + ret = register_trace_sched_switch(probe_wakeup_sched_switch, NULL); if (ret) { pr_info("sched trace: Couldn't activate tracepoint" " probe to kernel_sched_switch\n"); goto fail_deprobe_wake_new; } + ret = register_trace_sched_migrate_task(probe_wakeup_migrate_task, NULL); + if (ret) { + pr_info("wakeup trace: Couldn't activate tracepoint" + " probe to kernel_sched_migrate_task\n"); + return; + } + wakeup_reset(tr); /* @@ -307,60 +581,88 @@ static void start_wakeup_tracer(struct trace_array *tr) */ smp_wmb(); - register_ftrace_function(&trace_ops); - - if (tracing_is_enabled()) - tracer_enabled = 1; - else - tracer_enabled = 0; + if (start_func_tracer(tr, is_graph())) + printk(KERN_ERR "failed to start wakeup tracer\n"); return; fail_deprobe_wake_new: - unregister_trace_sched_wakeup_new(probe_wakeup); + unregister_trace_sched_wakeup_new(probe_wakeup, NULL); fail_deprobe: - unregister_trace_sched_wakeup(probe_wakeup); + unregister_trace_sched_wakeup(probe_wakeup, NULL); } static void stop_wakeup_tracer(struct trace_array *tr) { tracer_enabled = 0; - unregister_ftrace_function(&trace_ops); - unregister_trace_sched_switch(probe_wakeup_sched_switch); - unregister_trace_sched_wakeup_new(probe_wakeup); - unregister_trace_sched_wakeup(probe_wakeup); + stop_func_tracer(tr, is_graph()); + unregister_trace_sched_switch(probe_wakeup_sched_switch, NULL); + unregister_trace_sched_wakeup_new(probe_wakeup, NULL); + unregister_trace_sched_wakeup(probe_wakeup, NULL); + unregister_trace_sched_migrate_task(probe_wakeup_migrate_task, NULL); } +static bool wakeup_busy; + static int __wakeup_tracer_init(struct trace_array *tr) { - save_lat_flag = trace_flags & TRACE_ITER_LATENCY_FMT; - trace_flags |= TRACE_ITER_LATENCY_FMT; + save_flags = trace_flags; - tracing_max_latency = 0; + /* non overwrite screws up the latency tracers */ + set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1); + set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, 1); + + tr->max_latency = 0; wakeup_trace = tr; + ftrace_init_array_ops(tr, wakeup_tracer_call); start_wakeup_tracer(tr); + + wakeup_busy = true; return 0; } static int wakeup_tracer_init(struct trace_array *tr) { + if (wakeup_busy) + return -EBUSY; + + wakeup_dl = 0; wakeup_rt = 0; return __wakeup_tracer_init(tr); } static int wakeup_rt_tracer_init(struct trace_array *tr) { + if (wakeup_busy) + return -EBUSY; + + wakeup_dl = 0; wakeup_rt = 1; return __wakeup_tracer_init(tr); } +static int wakeup_dl_tracer_init(struct trace_array *tr) +{ + if (wakeup_busy) + return -EBUSY; + + wakeup_dl = 1; + wakeup_rt = 0; + return __wakeup_tracer_init(tr); +} + static void wakeup_tracer_reset(struct trace_array *tr) { + int lat_flag = save_flags & TRACE_ITER_LATENCY_FMT; + int overwrite_flag = save_flags & TRACE_ITER_OVERWRITE; + stop_wakeup_tracer(tr); /* make sure we put back any tasks we are tracing */ wakeup_reset(tr); - if (!save_lat_flag) - trace_flags &= ~TRACE_ITER_LATENCY_FMT; + set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag); + set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag); + ftrace_reset_array_ops(tr); + wakeup_busy = false; } static void wakeup_tracer_start(struct trace_array *tr) @@ -381,10 +683,19 @@ static struct tracer wakeup_tracer __read_mostly = .reset = wakeup_tracer_reset, .start = wakeup_tracer_start, .stop = wakeup_tracer_stop, - .print_max = 1, + .print_max = true, + .print_header = wakeup_print_header, + .print_line = wakeup_print_line, + .flags = &tracer_flags, + .set_flag = wakeup_set_flag, + .flag_changed = wakeup_flag_changed, #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_wakeup, #endif + .open = wakeup_trace_open, + .close = wakeup_trace_close, + .allow_instances = true, + .use_max_tr = true, }; static struct tracer wakeup_rt_tracer __read_mostly = @@ -394,11 +705,40 @@ static struct tracer wakeup_rt_tracer __read_mostly = .reset = wakeup_tracer_reset, .start = wakeup_tracer_start, .stop = wakeup_tracer_stop, - .wait_pipe = poll_wait_pipe, - .print_max = 1, + .print_max = true, + .print_header = wakeup_print_header, + .print_line = wakeup_print_line, + .flags = &tracer_flags, + .set_flag = wakeup_set_flag, + .flag_changed = wakeup_flag_changed, #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_wakeup, #endif + .open = wakeup_trace_open, + .close = wakeup_trace_close, + .allow_instances = true, + .use_max_tr = true, +}; + +static struct tracer wakeup_dl_tracer __read_mostly = +{ + .name = "wakeup_dl", + .init = wakeup_dl_tracer_init, + .reset = wakeup_tracer_reset, + .start = wakeup_tracer_start, + .stop = wakeup_tracer_stop, + .print_max = true, + .print_header = wakeup_print_header, + .print_line = wakeup_print_line, + .flags = &tracer_flags, + .set_flag = wakeup_set_flag, + .flag_changed = wakeup_flag_changed, +#ifdef CONFIG_FTRACE_SELFTEST + .selftest = trace_selftest_startup_wakeup, +#endif + .open = wakeup_trace_open, + .close = wakeup_trace_close, + .use_max_tr = true, }; __init static int init_wakeup_tracer(void) @@ -413,6 +753,10 @@ __init static int init_wakeup_tracer(void) if (ret) return ret; + ret = register_tracer(&wakeup_dl_tracer); + if (ret) + return ret; + return 0; } -device_initcall(init_wakeup_tracer); +core_initcall(init_wakeup_tracer); diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c index 00dd6485bdd..5ef60499dc8 100644 --- a/kernel/trace/trace_selftest.c +++ b/kernel/trace/trace_selftest.c @@ -3,6 +3,7 @@ #include <linux/stringify.h> #include <linux/kthread.h> #include <linux/delay.h> +#include <linux/slab.h> static inline int trace_valid_entry(struct trace_entry *entry) { @@ -12,23 +13,21 @@ static inline int trace_valid_entry(struct trace_entry *entry) case TRACE_WAKE: case TRACE_STACK: case TRACE_PRINT: - case TRACE_SPECIAL: case TRACE_BRANCH: case TRACE_GRAPH_ENT: case TRACE_GRAPH_RET: - case TRACE_HW_BRANCHES: return 1; } return 0; } -static int trace_test_buffer_cpu(struct trace_array *tr, int cpu) +static int trace_test_buffer_cpu(struct trace_buffer *buf, int cpu) { struct ring_buffer_event *event; struct trace_entry *entry; unsigned int loops = 0; - while ((event = ring_buffer_consume(tr->buffer, cpu, NULL))) { + while ((event = ring_buffer_consume(buf->buffer, cpu, NULL, NULL))) { entry = ring_buffer_event_data(event); /* @@ -59,16 +58,16 @@ static int trace_test_buffer_cpu(struct trace_array *tr, int cpu) * Test the trace buffer to see if all the elements * are still sane. */ -static int trace_test_buffer(struct trace_array *tr, unsigned long *count) +static int trace_test_buffer(struct trace_buffer *buf, unsigned long *count) { unsigned long flags, cnt = 0; int cpu, ret = 0; /* Don't allow flipping of max traces now */ local_irq_save(flags); - __raw_spin_lock(&ftrace_max_lock); + arch_spin_lock(&buf->tr->max_lock); - cnt = ring_buffer_entries(tr->buffer); + cnt = ring_buffer_entries(buf->buffer); /* * The trace_test_buffer_cpu runs a while loop to consume all data. @@ -79,12 +78,12 @@ static int trace_test_buffer(struct trace_array *tr, unsigned long *count) */ tracing_off(); for_each_possible_cpu(cpu) { - ret = trace_test_buffer_cpu(tr, cpu); + ret = trace_test_buffer_cpu(buf, cpu); if (ret) break; } tracing_on(); - __raw_spin_unlock(&ftrace_max_lock); + arch_spin_unlock(&buf->tr->max_lock); local_irq_restore(flags); if (count) @@ -102,13 +101,230 @@ static inline void warn_failed_init_tracer(struct tracer *trace, int init_ret) #ifdef CONFIG_DYNAMIC_FTRACE +static int trace_selftest_test_probe1_cnt; +static void trace_selftest_test_probe1_func(unsigned long ip, + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) +{ + trace_selftest_test_probe1_cnt++; +} + +static int trace_selftest_test_probe2_cnt; +static void trace_selftest_test_probe2_func(unsigned long ip, + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) +{ + trace_selftest_test_probe2_cnt++; +} + +static int trace_selftest_test_probe3_cnt; +static void trace_selftest_test_probe3_func(unsigned long ip, + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) +{ + trace_selftest_test_probe3_cnt++; +} + +static int trace_selftest_test_global_cnt; +static void trace_selftest_test_global_func(unsigned long ip, + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) +{ + trace_selftest_test_global_cnt++; +} + +static int trace_selftest_test_dyn_cnt; +static void trace_selftest_test_dyn_func(unsigned long ip, + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) +{ + trace_selftest_test_dyn_cnt++; +} + +static struct ftrace_ops test_probe1 = { + .func = trace_selftest_test_probe1_func, + .flags = FTRACE_OPS_FL_RECURSION_SAFE, +}; + +static struct ftrace_ops test_probe2 = { + .func = trace_selftest_test_probe2_func, + .flags = FTRACE_OPS_FL_RECURSION_SAFE, +}; + +static struct ftrace_ops test_probe3 = { + .func = trace_selftest_test_probe3_func, + .flags = FTRACE_OPS_FL_RECURSION_SAFE, +}; + +static void print_counts(void) +{ + printk("(%d %d %d %d %d) ", + trace_selftest_test_probe1_cnt, + trace_selftest_test_probe2_cnt, + trace_selftest_test_probe3_cnt, + trace_selftest_test_global_cnt, + trace_selftest_test_dyn_cnt); +} + +static void reset_counts(void) +{ + trace_selftest_test_probe1_cnt = 0; + trace_selftest_test_probe2_cnt = 0; + trace_selftest_test_probe3_cnt = 0; + trace_selftest_test_global_cnt = 0; + trace_selftest_test_dyn_cnt = 0; +} + +static int trace_selftest_ops(struct trace_array *tr, int cnt) +{ + int save_ftrace_enabled = ftrace_enabled; + struct ftrace_ops *dyn_ops; + char *func1_name; + char *func2_name; + int len1; + int len2; + int ret = -1; + + printk(KERN_CONT "PASSED\n"); + pr_info("Testing dynamic ftrace ops #%d: ", cnt); + + ftrace_enabled = 1; + reset_counts(); + + /* Handle PPC64 '.' name */ + func1_name = "*" __stringify(DYN_FTRACE_TEST_NAME); + func2_name = "*" __stringify(DYN_FTRACE_TEST_NAME2); + len1 = strlen(func1_name); + len2 = strlen(func2_name); + + /* + * Probe 1 will trace function 1. + * Probe 2 will trace function 2. + * Probe 3 will trace functions 1 and 2. + */ + ftrace_set_filter(&test_probe1, func1_name, len1, 1); + ftrace_set_filter(&test_probe2, func2_name, len2, 1); + ftrace_set_filter(&test_probe3, func1_name, len1, 1); + ftrace_set_filter(&test_probe3, func2_name, len2, 0); + + register_ftrace_function(&test_probe1); + register_ftrace_function(&test_probe2); + register_ftrace_function(&test_probe3); + /* First time we are running with main function */ + if (cnt > 1) { + ftrace_init_array_ops(tr, trace_selftest_test_global_func); + register_ftrace_function(tr->ops); + } + + DYN_FTRACE_TEST_NAME(); + + print_counts(); + + if (trace_selftest_test_probe1_cnt != 1) + goto out; + if (trace_selftest_test_probe2_cnt != 0) + goto out; + if (trace_selftest_test_probe3_cnt != 1) + goto out; + if (cnt > 1) { + if (trace_selftest_test_global_cnt == 0) + goto out; + } + + DYN_FTRACE_TEST_NAME2(); + + print_counts(); + + if (trace_selftest_test_probe1_cnt != 1) + goto out; + if (trace_selftest_test_probe2_cnt != 1) + goto out; + if (trace_selftest_test_probe3_cnt != 2) + goto out; + + /* Add a dynamic probe */ + dyn_ops = kzalloc(sizeof(*dyn_ops), GFP_KERNEL); + if (!dyn_ops) { + printk("MEMORY ERROR "); + goto out; + } + + dyn_ops->func = trace_selftest_test_dyn_func; + + register_ftrace_function(dyn_ops); + + trace_selftest_test_global_cnt = 0; + + DYN_FTRACE_TEST_NAME(); + + print_counts(); + + if (trace_selftest_test_probe1_cnt != 2) + goto out_free; + if (trace_selftest_test_probe2_cnt != 1) + goto out_free; + if (trace_selftest_test_probe3_cnt != 3) + goto out_free; + if (cnt > 1) { + if (trace_selftest_test_global_cnt == 0) + goto out; + } + if (trace_selftest_test_dyn_cnt == 0) + goto out_free; + + DYN_FTRACE_TEST_NAME2(); + + print_counts(); + + if (trace_selftest_test_probe1_cnt != 2) + goto out_free; + if (trace_selftest_test_probe2_cnt != 2) + goto out_free; + if (trace_selftest_test_probe3_cnt != 4) + goto out_free; + + ret = 0; + out_free: + unregister_ftrace_function(dyn_ops); + kfree(dyn_ops); + + out: + /* Purposely unregister in the same order */ + unregister_ftrace_function(&test_probe1); + unregister_ftrace_function(&test_probe2); + unregister_ftrace_function(&test_probe3); + if (cnt > 1) + unregister_ftrace_function(tr->ops); + ftrace_reset_array_ops(tr); + + /* Make sure everything is off */ + reset_counts(); + DYN_FTRACE_TEST_NAME(); + DYN_FTRACE_TEST_NAME(); + + if (trace_selftest_test_probe1_cnt || + trace_selftest_test_probe2_cnt || + trace_selftest_test_probe3_cnt || + trace_selftest_test_global_cnt || + trace_selftest_test_dyn_cnt) + ret = -1; + + ftrace_enabled = save_ftrace_enabled; + + return ret; +} + /* Test dynamic code modification and ftrace filters */ -int trace_selftest_startup_dynamic_tracing(struct tracer *trace, - struct trace_array *tr, - int (*func)(void)) +static int trace_selftest_startup_dynamic_tracing(struct tracer *trace, + struct trace_array *tr, + int (*func)(void)) { int save_ftrace_enabled = ftrace_enabled; - int save_tracer_enabled = tracer_enabled; unsigned long count; char *func_name; int ret; @@ -119,7 +335,6 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace, /* enable tracing, and record the filter function */ ftrace_enabled = 1; - tracer_enabled = 1; /* passed in by parameter to fool gcc from optimizing */ func(); @@ -132,7 +347,7 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace, func_name = "*" __stringify(DYN_FTRACE_TEST_NAME); /* filter only on our function */ - ftrace_set_filter(func_name, strlen(func_name), 1); + ftrace_set_global_filter(func_name, strlen(func_name), 1); /* enable tracing */ ret = tracer_init(trace, tr); @@ -145,7 +360,7 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace, msleep(100); /* we should have nothing in the buffer */ - ret = trace_test_buffer(tr, &count); + ret = trace_test_buffer(&tr->trace_buffer, &count); if (ret) goto out; @@ -166,49 +381,289 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace, ftrace_enabled = 0; /* check the trace buffer */ - ret = trace_test_buffer(tr, &count); - trace->reset(tr); + ret = trace_test_buffer(&tr->trace_buffer, &count); tracing_start(); /* we should only have one item */ if (!ret && count != 1) { + trace->reset(tr); printk(KERN_CONT ".. filter failed count=%ld ..", count); ret = -1; goto out; } + /* Test the ops with global tracing running */ + ret = trace_selftest_ops(tr, 1); + trace->reset(tr); + out: ftrace_enabled = save_ftrace_enabled; - tracer_enabled = save_tracer_enabled; /* Enable tracing on all functions again */ - ftrace_set_filter(NULL, 0, 1); + ftrace_set_global_filter(NULL, 0, 1); + + /* Test the ops with global tracing off */ + if (!ret) + ret = trace_selftest_ops(tr, 2); + + return ret; +} + +static int trace_selftest_recursion_cnt; +static void trace_selftest_test_recursion_func(unsigned long ip, + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) +{ + /* + * This function is registered without the recursion safe flag. + * The ftrace infrastructure should provide the recursion + * protection. If not, this will crash the kernel! + */ + if (trace_selftest_recursion_cnt++ > 10) + return; + DYN_FTRACE_TEST_NAME(); +} + +static void trace_selftest_test_recursion_safe_func(unsigned long ip, + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) +{ + /* + * We said we would provide our own recursion. By calling + * this function again, we should recurse back into this function + * and count again. But this only happens if the arch supports + * all of ftrace features and nothing else is using the function + * tracing utility. + */ + if (trace_selftest_recursion_cnt++) + return; + DYN_FTRACE_TEST_NAME(); +} + +static struct ftrace_ops test_rec_probe = { + .func = trace_selftest_test_recursion_func, +}; + +static struct ftrace_ops test_recsafe_probe = { + .func = trace_selftest_test_recursion_safe_func, + .flags = FTRACE_OPS_FL_RECURSION_SAFE, +}; + +static int +trace_selftest_function_recursion(void) +{ + int save_ftrace_enabled = ftrace_enabled; + char *func_name; + int len; + int ret; + + /* The previous test PASSED */ + pr_cont("PASSED\n"); + pr_info("Testing ftrace recursion: "); + + + /* enable tracing, and record the filter function */ + ftrace_enabled = 1; + + /* Handle PPC64 '.' name */ + func_name = "*" __stringify(DYN_FTRACE_TEST_NAME); + len = strlen(func_name); + + ret = ftrace_set_filter(&test_rec_probe, func_name, len, 1); + if (ret) { + pr_cont("*Could not set filter* "); + goto out; + } + + ret = register_ftrace_function(&test_rec_probe); + if (ret) { + pr_cont("*could not register callback* "); + goto out; + } + + DYN_FTRACE_TEST_NAME(); + + unregister_ftrace_function(&test_rec_probe); + + ret = -1; + if (trace_selftest_recursion_cnt != 1) { + pr_cont("*callback not called once (%d)* ", + trace_selftest_recursion_cnt); + goto out; + } + + trace_selftest_recursion_cnt = 1; + + pr_cont("PASSED\n"); + pr_info("Testing ftrace recursion safe: "); + + ret = ftrace_set_filter(&test_recsafe_probe, func_name, len, 1); + if (ret) { + pr_cont("*Could not set filter* "); + goto out; + } + + ret = register_ftrace_function(&test_recsafe_probe); + if (ret) { + pr_cont("*could not register callback* "); + goto out; + } + + DYN_FTRACE_TEST_NAME(); + + unregister_ftrace_function(&test_recsafe_probe); + + ret = -1; + if (trace_selftest_recursion_cnt != 2) { + pr_cont("*callback not called expected 2 times (%d)* ", + trace_selftest_recursion_cnt); + goto out; + } + + ret = 0; +out: + ftrace_enabled = save_ftrace_enabled; return ret; } #else # define trace_selftest_startup_dynamic_tracing(trace, tr, func) ({ 0; }) +# define trace_selftest_function_recursion() ({ 0; }) #endif /* CONFIG_DYNAMIC_FTRACE */ +static enum { + TRACE_SELFTEST_REGS_START, + TRACE_SELFTEST_REGS_FOUND, + TRACE_SELFTEST_REGS_NOT_FOUND, +} trace_selftest_regs_stat; + +static void trace_selftest_test_regs_func(unsigned long ip, + unsigned long pip, + struct ftrace_ops *op, + struct pt_regs *pt_regs) +{ + if (pt_regs) + trace_selftest_regs_stat = TRACE_SELFTEST_REGS_FOUND; + else + trace_selftest_regs_stat = TRACE_SELFTEST_REGS_NOT_FOUND; +} + +static struct ftrace_ops test_regs_probe = { + .func = trace_selftest_test_regs_func, + .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_SAVE_REGS, +}; + +static int +trace_selftest_function_regs(void) +{ + int save_ftrace_enabled = ftrace_enabled; + char *func_name; + int len; + int ret; + int supported = 0; + +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS + supported = 1; +#endif + + /* The previous test PASSED */ + pr_cont("PASSED\n"); + pr_info("Testing ftrace regs%s: ", + !supported ? "(no arch support)" : ""); + + /* enable tracing, and record the filter function */ + ftrace_enabled = 1; + + /* Handle PPC64 '.' name */ + func_name = "*" __stringify(DYN_FTRACE_TEST_NAME); + len = strlen(func_name); + + ret = ftrace_set_filter(&test_regs_probe, func_name, len, 1); + /* + * If DYNAMIC_FTRACE is not set, then we just trace all functions. + * This test really doesn't care. + */ + if (ret && ret != -ENODEV) { + pr_cont("*Could not set filter* "); + goto out; + } + + ret = register_ftrace_function(&test_regs_probe); + /* + * Now if the arch does not support passing regs, then this should + * have failed. + */ + if (!supported) { + if (!ret) { + pr_cont("*registered save-regs without arch support* "); + goto out; + } + test_regs_probe.flags |= FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED; + ret = register_ftrace_function(&test_regs_probe); + } + if (ret) { + pr_cont("*could not register callback* "); + goto out; + } + + + DYN_FTRACE_TEST_NAME(); + + unregister_ftrace_function(&test_regs_probe); + + ret = -1; + + switch (trace_selftest_regs_stat) { + case TRACE_SELFTEST_REGS_START: + pr_cont("*callback never called* "); + goto out; + + case TRACE_SELFTEST_REGS_FOUND: + if (supported) + break; + pr_cont("*callback received regs without arch support* "); + goto out; + + case TRACE_SELFTEST_REGS_NOT_FOUND: + if (!supported) + break; + pr_cont("*callback received NULL regs* "); + goto out; + } + + ret = 0; +out: + ftrace_enabled = save_ftrace_enabled; + + return ret; +} + /* * Simple verification test of ftrace function tracer. * Enable ftrace, sleep 1/10 second, and then read the trace * buffer to see if all is in order. */ -int +__init int trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr) { int save_ftrace_enabled = ftrace_enabled; - int save_tracer_enabled = tracer_enabled; unsigned long count; int ret; +#ifdef CONFIG_DYNAMIC_FTRACE + if (ftrace_filter_param) { + printk(KERN_CONT " ... kernel command line filter set: force PASS ... "); + return 0; + } +#endif + /* make sure msleep has been recorded */ msleep(1); /* start the tracing */ ftrace_enabled = 1; - tracer_enabled = 1; ret = tracer_init(trace, tr); if (ret) { @@ -223,7 +678,7 @@ trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr) ftrace_enabled = 0; /* check the trace buffer */ - ret = trace_test_buffer(tr, &count); + ret = trace_test_buffer(&tr->trace_buffer, &count); trace->reset(tr); tracing_start(); @@ -235,10 +690,16 @@ trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr) ret = trace_selftest_startup_dynamic_tracing(trace, tr, DYN_FTRACE_TEST_NAME); + if (ret) + goto out; + ret = trace_selftest_function_recursion(); + if (ret) + goto out; + + ret = trace_selftest_function_regs(); out: ftrace_enabled = save_ftrace_enabled; - tracer_enabled = save_tracer_enabled; /* kill ftrace totally if we failed */ if (ret) @@ -254,7 +715,6 @@ trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr) /* Maximum number of functions to trace before diagnosing a hang */ #define GRAPH_MAX_FUNC_TEST 100000000 -static void __ftrace_dump(bool disable_tracing); static unsigned int graph_hang_thresh; /* Wrap the real function entry probe to avoid possible hanging */ @@ -264,8 +724,11 @@ static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace) if (unlikely(++graph_hang_thresh > GRAPH_MAX_FUNC_TEST)) { ftrace_graph_stop(); printk(KERN_WARNING "BUG: Function graph tracer hang!\n"); - if (ftrace_dump_on_oops) - __ftrace_dump(false); + if (ftrace_dump_on_oops) { + ftrace_dump(DUMP_ALL); + /* ftrace_dump() disables tracing */ + tracing_on(); + } return 0; } @@ -276,18 +739,26 @@ static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace) * Pretty much the same than for the function tracer from which the selftest * has been borrowed. */ -int +__init int trace_selftest_startup_function_graph(struct tracer *trace, struct trace_array *tr) { int ret; unsigned long count; +#ifdef CONFIG_DYNAMIC_FTRACE + if (ftrace_filter_param) { + printk(KERN_CONT " ... kernel command line filter set: force PASS ... "); + return 0; + } +#endif + /* * Simulate the init() callback but we attach a watchdog callback * to detect and recover from possible hangs */ - tracing_reset_online_cpus(tr); + tracing_reset_online_cpus(&tr->trace_buffer); + set_graph_array(tr); ret = register_ftrace_graph(&trace_graph_return, &trace_graph_entry_watchdog); if (ret) { @@ -309,7 +780,7 @@ trace_selftest_startup_function_graph(struct tracer *trace, tracing_stop(); /* check the trace buffer */ - ret = trace_test_buffer(tr, &count); + ret = trace_test_buffer(&tr->trace_buffer, &count); trace->reset(tr); tracing_start(); @@ -336,7 +807,7 @@ out: int trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr) { - unsigned long save_max = tracing_max_latency; + unsigned long save_max = tr->max_latency; unsigned long count; int ret; @@ -348,7 +819,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr) } /* reset the max latency */ - tracing_max_latency = 0; + tr->max_latency = 0; /* disable interrupts for a bit */ local_irq_disable(); udelay(100); @@ -364,9 +835,9 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr) /* stop the tracing. */ tracing_stop(); /* check both trace buffers */ - ret = trace_test_buffer(tr, NULL); + ret = trace_test_buffer(&tr->trace_buffer, NULL); if (!ret) - ret = trace_test_buffer(&max_tr, &count); + ret = trace_test_buffer(&tr->max_buffer, &count); trace->reset(tr); tracing_start(); @@ -375,7 +846,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr) ret = -1; } - tracing_max_latency = save_max; + tr->max_latency = save_max; return ret; } @@ -385,7 +856,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr) int trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr) { - unsigned long save_max = tracing_max_latency; + unsigned long save_max = tr->max_latency; unsigned long count; int ret; @@ -410,7 +881,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr) } /* reset the max latency */ - tracing_max_latency = 0; + tr->max_latency = 0; /* disable preemption for a bit */ preempt_disable(); udelay(100); @@ -426,9 +897,9 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr) /* stop the tracing. */ tracing_stop(); /* check both trace buffers */ - ret = trace_test_buffer(tr, NULL); + ret = trace_test_buffer(&tr->trace_buffer, NULL); if (!ret) - ret = trace_test_buffer(&max_tr, &count); + ret = trace_test_buffer(&tr->max_buffer, &count); trace->reset(tr); tracing_start(); @@ -437,7 +908,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr) ret = -1; } - tracing_max_latency = save_max; + tr->max_latency = save_max; return ret; } @@ -447,7 +918,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr) int trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *tr) { - unsigned long save_max = tracing_max_latency; + unsigned long save_max = tr->max_latency; unsigned long count; int ret; @@ -472,7 +943,7 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array * } /* reset the max latency */ - tracing_max_latency = 0; + tr->max_latency = 0; /* disable preemption and interrupts for a bit */ preempt_disable(); @@ -492,11 +963,11 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array * /* stop the tracing. */ tracing_stop(); /* check both trace buffers */ - ret = trace_test_buffer(tr, NULL); + ret = trace_test_buffer(&tr->trace_buffer, NULL); if (ret) goto out; - ret = trace_test_buffer(&max_tr, &count); + ret = trace_test_buffer(&tr->max_buffer, &count); if (ret) goto out; @@ -507,7 +978,7 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array * } /* do the test by disabling interrupts first this time */ - tracing_max_latency = 0; + tr->max_latency = 0; tracing_start(); trace->start(tr); @@ -522,11 +993,11 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array * /* stop the tracing. */ tracing_stop(); /* check both trace buffers */ - ret = trace_test_buffer(tr, NULL); + ret = trace_test_buffer(&tr->trace_buffer, NULL); if (ret) goto out; - ret = trace_test_buffer(&max_tr, &count); + ret = trace_test_buffer(&tr->max_buffer, &count); if (!ret && !count) { printk(KERN_CONT ".. no entries found .."); @@ -538,7 +1009,7 @@ out: tracing_start(); out_no_start: trace->reset(tr); - tracing_max_latency = save_max; + tr->max_latency = save_max; return ret; } @@ -556,11 +1027,16 @@ trace_selftest_startup_nop(struct tracer *trace, struct trace_array *tr) #ifdef CONFIG_SCHED_TRACER static int trace_wakeup_test_thread(void *data) { - /* Make this a RT thread, doesn't need to be too high */ - struct sched_param param = { .sched_priority = 5 }; + /* Make this a -deadline thread */ + static const struct sched_attr attr = { + .sched_policy = SCHED_DEADLINE, + .sched_runtime = 100000ULL, + .sched_deadline = 10000000ULL, + .sched_period = 10000000ULL + }; struct completion *x = data; - sched_setscheduler(current, SCHED_FIFO, ¶m); + sched_setattr(current, &attr); /* Make it know we have a new prio */ complete(x); @@ -569,11 +1045,13 @@ static int trace_wakeup_test_thread(void *data) set_current_state(TASK_INTERRUPTIBLE); schedule(); + complete(x); + /* we are awake, now wait to disappear */ while (!kthread_should_stop()) { /* - * This is an RT task, do short sleeps to let - * others run. + * This will likely be the system top priority + * task, do short sleeps to let others run. */ msleep(100); } @@ -584,23 +1062,23 @@ static int trace_wakeup_test_thread(void *data) int trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr) { - unsigned long save_max = tracing_max_latency; + unsigned long save_max = tr->max_latency; struct task_struct *p; - struct completion isrt; + struct completion is_ready; unsigned long count; int ret; - init_completion(&isrt); + init_completion(&is_ready); - /* create a high prio thread */ - p = kthread_run(trace_wakeup_test_thread, &isrt, "ftrace-test"); + /* create a -deadline thread */ + p = kthread_run(trace_wakeup_test_thread, &is_ready, "ftrace-test"); if (IS_ERR(p)) { printk(KERN_CONT "Failed to create ftrace wakeup test thread "); return -1; } - /* make sure the thread is running at an RT prio */ - wait_for_completion(&isrt); + /* make sure the thread is running at -deadline policy */ + wait_for_completion(&is_ready); /* start the tracing */ ret = tracer_init(trace, tr); @@ -610,39 +1088,37 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr) } /* reset the max latency */ - tracing_max_latency = 0; + tr->max_latency = 0; - /* sleep to let the RT thread sleep too */ - msleep(100); + while (p->on_rq) { + /* + * Sleep to make sure the -deadline thread is asleep too. + * On virtual machines we can't rely on timings, + * but we want to make sure this test still works. + */ + msleep(100); + } - /* - * Yes this is slightly racy. It is possible that for some - * strange reason that the RT thread we created, did not - * call schedule for 100ms after doing the completion, - * and we do a wakeup on a task that already is awake. - * But that is extremely unlikely, and the worst thing that - * happens in such a case, is that we disable tracing. - * Honestly, if this race does happen something is horrible - * wrong with the system. - */ + init_completion(&is_ready); wake_up_process(p); - /* give a little time to let the thread wake up */ - msleep(100); + /* Wait for the task to wake up */ + wait_for_completion(&is_ready); /* stop the tracing. */ tracing_stop(); /* check both trace buffers */ - ret = trace_test_buffer(tr, NULL); + ret = trace_test_buffer(&tr->trace_buffer, NULL); + printk("ret = %d\n", ret); if (!ret) - ret = trace_test_buffer(&max_tr, &count); + ret = trace_test_buffer(&tr->max_buffer, &count); trace->reset(tr); tracing_start(); - tracing_max_latency = save_max; + tr->max_latency = save_max; /* kill the thread */ kthread_stop(p); @@ -675,7 +1151,7 @@ trace_selftest_startup_sched_switch(struct tracer *trace, struct trace_array *tr /* stop the tracing. */ tracing_stop(); /* check the trace buffer */ - ret = trace_test_buffer(tr, &count); + ret = trace_test_buffer(&tr->trace_buffer, &count); trace->reset(tr); tracing_start(); @@ -688,38 +1164,6 @@ trace_selftest_startup_sched_switch(struct tracer *trace, struct trace_array *tr } #endif /* CONFIG_CONTEXT_SWITCH_TRACER */ -#ifdef CONFIG_SYSPROF_TRACER -int -trace_selftest_startup_sysprof(struct tracer *trace, struct trace_array *tr) -{ - unsigned long count; - int ret; - - /* start the tracing */ - ret = tracer_init(trace, tr); - if (ret) { - warn_failed_init_tracer(trace, ret); - return ret; - } - - /* Sleep for a 1/10 of a second */ - msleep(100); - /* stop the tracing. */ - tracing_stop(); - /* check the trace buffer */ - ret = trace_test_buffer(tr, &count); - trace->reset(tr); - tracing_start(); - - if (!ret && !count) { - printk(KERN_CONT ".. no entries found .."); - ret = -1; - } - - return ret; -} -#endif /* CONFIG_SYSPROF_TRACER */ - #ifdef CONFIG_BRANCH_TRACER int trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr) @@ -739,7 +1183,7 @@ trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr) /* stop the tracing. */ tracing_stop(); /* check the trace buffer */ - ret = trace_test_buffer(tr, &count); + ret = trace_test_buffer(&tr->trace_buffer, &count); trace->reset(tr); tracing_start(); @@ -752,58 +1196,3 @@ trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr) } #endif /* CONFIG_BRANCH_TRACER */ -#ifdef CONFIG_HW_BRANCH_TRACER -int -trace_selftest_startup_hw_branches(struct tracer *trace, - struct trace_array *tr) -{ - struct trace_iterator *iter; - struct tracer tracer; - unsigned long count; - int ret; - - if (!trace->open) { - printk(KERN_CONT "missing open function..."); - return -1; - } - - ret = tracer_init(trace, tr); - if (ret) { - warn_failed_init_tracer(trace, ret); - return ret; - } - - /* - * The hw-branch tracer needs to collect the trace from the various - * cpu trace buffers - before tracing is stopped. - */ - iter = kzalloc(sizeof(*iter), GFP_KERNEL); - if (!iter) - return -ENOMEM; - - memcpy(&tracer, trace, sizeof(tracer)); - - iter->trace = &tracer; - iter->tr = tr; - iter->pos = -1; - mutex_init(&iter->mutex); - - trace->open(iter); - - mutex_destroy(&iter->mutex); - kfree(iter); - - tracing_stop(); - - ret = trace_test_buffer(tr, &count); - trace->reset(tr); - tracing_start(); - - if (!ret && !count) { - printk(KERN_CONT "no entries found.."); - ret = -1; - } - - return ret; -} -#endif /* CONFIG_HW_BRANCH_TRACER */ diff --git a/kernel/trace/trace_selftest_dynamic.c b/kernel/trace/trace_selftest_dynamic.c index 54dd77cce5b..b4c475a0a48 100644 --- a/kernel/trace/trace_selftest_dynamic.c +++ b/kernel/trace/trace_selftest_dynamic.c @@ -5,3 +5,9 @@ int DYN_FTRACE_TEST_NAME(void) /* used to call mcount */ return 0; } + +int DYN_FTRACE_TEST_NAME2(void) +{ + /* used to call mcount */ + return 0; +} diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c index 2d7aebd71db..8a4e5cb66a4 100644 --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -13,48 +13,93 @@ #include <linux/sysctl.h> #include <linux/init.h> #include <linux/fs.h> +#include <linux/magic.h> + +#include <asm/setup.h> + #include "trace.h" #define STACK_TRACE_ENTRIES 500 +#ifdef CC_USING_FENTRY +# define fentry 1 +#else +# define fentry 0 +#endif + static unsigned long stack_dump_trace[STACK_TRACE_ENTRIES+1] = { [0 ... (STACK_TRACE_ENTRIES)] = ULONG_MAX }; static unsigned stack_dump_index[STACK_TRACE_ENTRIES]; +/* + * Reserve one entry for the passed in ip. This will allow + * us to remove most or all of the stack size overhead + * added by the stack tracer itself. + */ static struct stack_trace max_stack_trace = { - .max_entries = STACK_TRACE_ENTRIES, - .entries = stack_dump_trace, + .max_entries = STACK_TRACE_ENTRIES - 1, + .entries = &stack_dump_trace[1], }; static unsigned long max_stack_size; -static raw_spinlock_t max_stack_lock = - (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; +static arch_spinlock_t max_stack_lock = + (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; -static int stack_trace_disabled __read_mostly; static DEFINE_PER_CPU(int, trace_active); static DEFINE_MUTEX(stack_sysctl_mutex); int stack_tracer_enabled; static int last_stack_tracer_enabled; -static inline void check_stack(void) +static inline void print_max_stack(void) +{ + long i; + int size; + + pr_emerg(" Depth Size Location (%d entries)\n" + " ----- ---- --------\n", + max_stack_trace.nr_entries - 1); + + for (i = 0; i < max_stack_trace.nr_entries; i++) { + if (stack_dump_trace[i] == ULONG_MAX) + break; + if (i+1 == max_stack_trace.nr_entries || + stack_dump_trace[i+1] == ULONG_MAX) + size = stack_dump_index[i]; + else + size = stack_dump_index[i] - stack_dump_index[i+1]; + + pr_emerg("%3ld) %8d %5d %pS\n", i, stack_dump_index[i], + size, (void *)stack_dump_trace[i]); + } +} + +static inline void +check_stack(unsigned long ip, unsigned long *stack) { - unsigned long this_size, flags; - unsigned long *p, *top, *start; + unsigned long this_size, flags; unsigned long *p, *top, *start; + static int tracer_frame; + int frame_size = ACCESS_ONCE(tracer_frame); int i; - this_size = ((unsigned long)&this_size) & (THREAD_SIZE-1); + this_size = ((unsigned long)stack) & (THREAD_SIZE-1); this_size = THREAD_SIZE - this_size; + /* Remove the frame of the tracer */ + this_size -= frame_size; if (this_size <= max_stack_size) return; /* we do not handle interrupt stacks yet */ - if (!object_is_on_stack(&this_size)) + if (!object_is_on_stack(stack)) return; local_irq_save(flags); - __raw_spin_lock(&max_stack_lock); + arch_spin_lock(&max_stack_lock); + + /* In case another CPU set the tracer_frame on us */ + if (unlikely(!frame_size)) + this_size -= tracer_frame; /* a race could have already updated it */ if (this_size <= max_stack_size) @@ -62,16 +107,28 @@ static inline void check_stack(void) max_stack_size = this_size; - max_stack_trace.nr_entries = 0; - max_stack_trace.skip = 3; + max_stack_trace.nr_entries = 0; + + if (using_ftrace_ops_list_func()) + max_stack_trace.skip = 4; + else + max_stack_trace.skip = 3; save_stack_trace(&max_stack_trace); /* + * Add the passed in ip from the function tracer. + * Searching for this on the stack will skip over + * most of the overhead from the stack tracer itself. + */ + stack_dump_trace[0] = ip; + max_stack_trace.nr_entries++; + + /* * Now find where in the stack these are. */ i = 0; - start = &this_size; + start = stack; top = (unsigned long *) (((unsigned long)start & ~(THREAD_SIZE-1)) + THREAD_SIZE); @@ -95,6 +152,18 @@ static inline void check_stack(void) found = 1; /* Start the search from here */ start = p + 1; + /* + * We do not want to show the overhead + * of the stack tracer stack in the + * max stack. If we haven't figured + * out what that is, then figure it out + * now. + */ + if (unlikely(!tracer_frame) && i == 1) { + tracer_frame = (p - stack) * + sizeof(unsigned long); + max_stack_size -= tracer_frame; + } } } @@ -102,37 +171,62 @@ static inline void check_stack(void) i++; } + if ((current != &init_task && + *(end_of_stack(current)) != STACK_END_MAGIC)) { + print_max_stack(); + BUG(); + } + out: - __raw_spin_unlock(&max_stack_lock); + arch_spin_unlock(&max_stack_lock); local_irq_restore(flags); } static void -stack_trace_call(unsigned long ip, unsigned long parent_ip) +stack_trace_call(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct pt_regs *pt_regs) { - int cpu, resched; + unsigned long stack; + int cpu; - if (unlikely(!ftrace_enabled || stack_trace_disabled)) - return; - - resched = ftrace_preempt_disable(); + preempt_disable_notrace(); cpu = raw_smp_processor_id(); /* no atomic needed, we only modify this variable by this cpu */ if (per_cpu(trace_active, cpu)++ != 0) goto out; - check_stack(); + /* + * When fentry is used, the traced function does not get + * its stack frame set up, and we lose the parent. + * The ip is pretty useless because the function tracer + * was called before that function set up its stack frame. + * In this case, we use the parent ip. + * + * By adding the return address of either the parent ip + * or the current ip we can disregard most of the stack usage + * caused by the stack tracer itself. + * + * The function tracer always reports the address of where the + * mcount call was, but the stack will hold the return address. + */ + if (fentry) + ip = parent_ip; + else + ip += MCOUNT_INSN_SIZE; + + check_stack(ip, &stack); out: per_cpu(trace_active, cpu)--; /* prevent recursion in schedule */ - ftrace_preempt_enable(resched); + preempt_enable_notrace(); } static struct ftrace_ops trace_ops __read_mostly = { .func = stack_trace_call, + .flags = FTRACE_OPS_FL_RECURSION_SAFE, }; static ssize_t @@ -155,25 +249,28 @@ stack_max_size_write(struct file *filp, const char __user *ubuf, { long *ptr = filp->private_data; unsigned long val, flags; - char buf[64]; int ret; + int cpu; - if (count >= sizeof(buf)) - return -EINVAL; - - if (copy_from_user(&buf, ubuf, count)) - return -EFAULT; - - buf[count] = 0; - - ret = strict_strtoul(buf, 10, &val); - if (ret < 0) + ret = kstrtoul_from_user(ubuf, count, 10, &val); + if (ret) return ret; local_irq_save(flags); - __raw_spin_lock(&max_stack_lock); + + /* + * In case we trace inside arch_spin_lock() or after (NMI), + * we will cause circular lock, so we also need to increase + * the percpu trace_active here. + */ + cpu = smp_processor_id(); + per_cpu(trace_active, cpu)++; + + arch_spin_lock(&max_stack_lock); *ptr = val; - __raw_spin_unlock(&max_stack_lock); + arch_spin_unlock(&max_stack_lock); + + per_cpu(trace_active, cpu)--; local_irq_restore(flags); return count; @@ -183,66 +280,62 @@ static const struct file_operations stack_max_size_fops = { .open = tracing_open_generic, .read = stack_max_size_read, .write = stack_max_size_write, + .llseek = default_llseek, }; static void * -t_next(struct seq_file *m, void *v, loff_t *pos) +__next(struct seq_file *m, loff_t *pos) { - long i; - - (*pos)++; + long n = *pos - 1; - if (v == SEQ_START_TOKEN) - i = 0; - else { - i = *(long *)v; - i++; - } - - if (i >= max_stack_trace.nr_entries || - stack_dump_trace[i] == ULONG_MAX) + if (n >= max_stack_trace.nr_entries || stack_dump_trace[n] == ULONG_MAX) return NULL; - m->private = (void *)i; - + m->private = (void *)n; return &m->private; } +static void * +t_next(struct seq_file *m, void *v, loff_t *pos) +{ + (*pos)++; + return __next(m, pos); +} + static void *t_start(struct seq_file *m, loff_t *pos) { - void *t = SEQ_START_TOKEN; - loff_t l = 0; + int cpu; local_irq_disable(); - __raw_spin_lock(&max_stack_lock); + + cpu = smp_processor_id(); + per_cpu(trace_active, cpu)++; + + arch_spin_lock(&max_stack_lock); if (*pos == 0) return SEQ_START_TOKEN; - for (; t && l < *pos; t = t_next(m, t, &l)) - ; - - return t; + return __next(m, pos); } static void t_stop(struct seq_file *m, void *p) { - __raw_spin_unlock(&max_stack_lock); + int cpu; + + arch_spin_unlock(&max_stack_lock); + + cpu = smp_processor_id(); + per_cpu(trace_active, cpu)--; + local_irq_enable(); } static int trace_lookup_stack(struct seq_file *m, long i) { unsigned long addr = stack_dump_trace[i]; -#ifdef CONFIG_KALLSYMS - char str[KSYM_SYMBOL_LEN]; - sprint_symbol(str, addr); - - return seq_printf(m, "%s\n", str); -#else - return seq_printf(m, "%p\n", (void*)addr); -#endif + return seq_printf(m, "%pS\n", (void *)addr); } static void print_disabled(struct seq_file *m) @@ -301,35 +394,47 @@ static const struct seq_operations stack_trace_seq_ops = { static int stack_trace_open(struct inode *inode, struct file *file) { - int ret; - - ret = seq_open(file, &stack_trace_seq_ops); - - return ret; + return seq_open(file, &stack_trace_seq_ops); } static const struct file_operations stack_trace_fops = { .open = stack_trace_open, .read = seq_read, .llseek = seq_lseek, + .release = seq_release, +}; + +static int +stack_trace_filter_open(struct inode *inode, struct file *file) +{ + return ftrace_regex_open(&trace_ops, FTRACE_ITER_FILTER, + inode, file); +} + +static const struct file_operations stack_trace_filter_fops = { + .open = stack_trace_filter_open, + .read = seq_read, + .write = ftrace_filter_write, + .llseek = tracing_lseek, + .release = ftrace_regex_release, }; int stack_trace_sysctl(struct ctl_table *table, int write, - struct file *file, void __user *buffer, size_t *lenp, + void __user *buffer, size_t *lenp, loff_t *ppos) { int ret; mutex_lock(&stack_sysctl_mutex); - ret = proc_dointvec(table, write, file, buffer, lenp, ppos); + ret = proc_dointvec(table, write, buffer, lenp, ppos); if (ret || !write || - (last_stack_tracer_enabled == stack_tracer_enabled)) + (last_stack_tracer_enabled == !!stack_tracer_enabled)) goto out; - last_stack_tracer_enabled = stack_tracer_enabled; + last_stack_tracer_enabled = !!stack_tracer_enabled; if (stack_tracer_enabled) register_ftrace_function(&trace_ops); @@ -341,8 +446,13 @@ stack_trace_sysctl(struct ctl_table *table, int write, return ret; } +static char stack_trace_filter_buf[COMMAND_LINE_SIZE+1] __initdata; + static __init int enable_stacktrace(char *str) { + if (strncmp(str, "_filter=", 8) == 0) + strncpy(stack_trace_filter_buf, str+8, COMMAND_LINE_SIZE); + stack_tracer_enabled = 1; last_stack_tracer_enabled = 1; return 1; @@ -354,6 +464,8 @@ static __init int stack_trace_init(void) struct dentry *d_tracer; d_tracer = tracing_init_dentry(); + if (!d_tracer) + return 0; trace_create_file("stack_max_size", 0644, d_tracer, &max_stack_size, &stack_max_size_fops); @@ -361,6 +473,12 @@ static __init int stack_trace_init(void) trace_create_file("stack_trace", 0444, d_tracer, NULL, &stack_trace_fops); + trace_create_file("stack_trace_filter", 0444, d_tracer, + NULL, &stack_trace_filter_fops); + + if (stack_trace_filter_buf[0]) + ftrace_set_early_filter(&trace_ops, stack_trace_filter_buf, 1); + if (stack_tracer_enabled) register_ftrace_function(&trace_ops); diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c index e66f5e49334..7af67360b33 100644 --- a/kernel/trace/trace_stat.c +++ b/kernel/trace/trace_stat.c @@ -10,6 +10,7 @@ #include <linux/list.h> +#include <linux/slab.h> #include <linux/rbtree.h> #include <linux/debugfs.h> #include "trace_stat.h" @@ -42,51 +43,30 @@ static DEFINE_MUTEX(all_stat_sessions_mutex); /* The root directory for all stat files */ static struct dentry *stat_dir; -/* - * Iterate through the rbtree using a post order traversal path - * to release the next node. - * It won't necessary release one at each iteration - * but it will at least advance closer to the next one - * to be released. - */ -static struct rb_node *release_next(struct rb_node *node) +static void __reset_stat_session(struct stat_session *session) { - struct stat_node *snode; - struct rb_node *parent = rb_parent(node); - - if (node->rb_left) - return node->rb_left; - else if (node->rb_right) - return node->rb_right; - else { - if (!parent) - ; - else if (parent->rb_left == node) - parent->rb_left = NULL; - else - parent->rb_right = NULL; + struct stat_node *snode, *n; - snode = container_of(node, struct stat_node, node); + rbtree_postorder_for_each_entry_safe(snode, n, &session->stat_root, node) { + if (session->ts->stat_release) + session->ts->stat_release(snode->stat); kfree(snode); - - return parent; } + + session->stat_root = RB_ROOT; } static void reset_stat_session(struct stat_session *session) { - struct rb_node *node = session->stat_root.rb_node; - - while (node) - node = release_next(node); - - session->stat_root = RB_ROOT; + mutex_lock(&session->stat_mutex); + __reset_stat_session(session); + mutex_unlock(&session->stat_mutex); } static void destroy_session(struct stat_session *session) { debugfs_remove(session->file); - reset_stat_session(session); + __reset_stat_session(session); mutex_destroy(&session->stat_mutex); kfree(session); } @@ -150,7 +130,7 @@ static int stat_seq_init(struct stat_session *session) int i; mutex_lock(&session->stat_mutex); - reset_stat_session(session); + __reset_stat_session(session); if (!ts->stat_cmp) ts->stat_cmp = dummy_cmp; @@ -183,7 +163,7 @@ exit: return ret; exit_free_rbtree: - reset_stat_session(session); + __reset_stat_session(session); mutex_unlock(&session->stat_mutex); return ret; } @@ -193,17 +173,21 @@ static void *stat_seq_start(struct seq_file *s, loff_t *pos) { struct stat_session *session = s->private; struct rb_node *node; + int n = *pos; int i; /* Prevent from tracer switch or rbtree modification */ mutex_lock(&session->stat_mutex); /* If we are in the beginning of the file, print the headers */ - if (!*pos && session->ts->stat_headers) - return SEQ_START_TOKEN; + if (session->ts->stat_headers) { + if (n == 0) + return SEQ_START_TOKEN; + n--; + } node = rb_first(&session->stat_root); - for (i = 0; node && i < *pos; i++) + for (i = 0; node && i < n; i++) node = rb_next(node); return node; @@ -250,16 +234,21 @@ static const struct seq_operations trace_stat_seq_ops = { static int tracing_stat_open(struct inode *inode, struct file *file) { int ret; - + struct seq_file *m; struct stat_session *session = inode->i_private; + ret = stat_seq_init(session); + if (ret) + return ret; + ret = seq_open(file, &trace_stat_seq_ops); - if (!ret) { - struct seq_file *m = file->private_data; - m->private = session; - ret = stat_seq_init(session); + if (ret) { + reset_stat_session(session); + return ret; } + m = file->private_data; + m->private = session; return ret; } @@ -270,11 +259,9 @@ static int tracing_stat_release(struct inode *i, struct file *f) { struct stat_session *session = i->i_private; - mutex_lock(&session->stat_mutex); reset_stat_session(session); - mutex_unlock(&session->stat_mutex); - return 0; + return seq_release(i, f); } static const struct file_operations tracing_stat_fops = { @@ -289,6 +276,8 @@ static int tracing_stat_init(void) struct dentry *d_tracing; d_tracing = tracing_init_dentry(); + if (!d_tracing) + return 0; stat_dir = debugfs_create_dir("trace_stat", d_tracing); if (!stat_dir) diff --git a/kernel/trace/trace_stat.h b/kernel/trace/trace_stat.h index f3546a2cd82..8f03914b9a6 100644 --- a/kernel/trace/trace_stat.h +++ b/kernel/trace/trace_stat.h @@ -18,6 +18,8 @@ struct tracer_stat { int (*stat_cmp)(void *p1, void *p2); /* Print a stat entry */ int (*stat_show)(struct seq_file *s, void *p); + /* Release an entry */ + void (*stat_release)(void *stat); /* Print the headers of your stat entries */ int (*stat_headers)(struct seq_file *s); }; diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 5e579645ac8..759d5e00451 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -1,33 +1,114 @@ #include <trace/syscall.h> +#include <trace/events/syscalls.h> +#include <linux/syscalls.h> +#include <linux/slab.h> #include <linux/kernel.h> +#include <linux/module.h> /* for MODULE_NAME_LEN via KSYM_SYMBOL_LEN */ +#include <linux/ftrace.h> +#include <linux/perf_event.h> #include <asm/syscall.h> #include "trace_output.h" #include "trace.h" -/* Keep a counter of the syscall tracing users */ -static int refcount; - -/* Prevent from races on thread flags toggling */ static DEFINE_MUTEX(syscall_trace_lock); -/* Option to display the parameters types */ -enum { - TRACE_SYSCALLS_OPT_TYPES = 0x1, -}; +static int syscall_enter_register(struct ftrace_event_call *event, + enum trace_reg type, void *data); +static int syscall_exit_register(struct ftrace_event_call *event, + enum trace_reg type, void *data); -static struct tracer_opt syscalls_opts[] = { - { TRACER_OPT(syscall_arg_type, TRACE_SYSCALLS_OPT_TYPES) }, - { } -}; +static struct list_head * +syscall_get_enter_fields(struct ftrace_event_call *call) +{ + struct syscall_metadata *entry = call->data; -static struct tracer_flags syscalls_flags = { - .val = 0, /* By default: no parameters types */ - .opts = syscalls_opts -}; + return &entry->enter_fields; +} + +extern struct syscall_metadata *__start_syscalls_metadata[]; +extern struct syscall_metadata *__stop_syscalls_metadata[]; + +static struct syscall_metadata **syscalls_metadata; + +#ifndef ARCH_HAS_SYSCALL_MATCH_SYM_NAME +static inline bool arch_syscall_match_sym_name(const char *sym, const char *name) +{ + /* + * Only compare after the "sys" prefix. Archs that use + * syscall wrappers may have syscalls symbols aliases prefixed + * with ".SyS" or ".sys" instead of "sys", leading to an unwanted + * mismatch. + */ + return !strcmp(sym + 3, name + 3); +} +#endif + +#ifdef ARCH_TRACE_IGNORE_COMPAT_SYSCALLS +/* + * Some architectures that allow for 32bit applications + * to run on a 64bit kernel, do not map the syscalls for + * the 32bit tasks the same as they do for 64bit tasks. + * + * *cough*x86*cough* + * + * In such a case, instead of reporting the wrong syscalls, + * simply ignore them. + * + * For an arch to ignore the compat syscalls it needs to + * define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS as well as + * define the function arch_trace_is_compat_syscall() to let + * the tracing system know that it should ignore it. + */ +static int +trace_get_syscall_nr(struct task_struct *task, struct pt_regs *regs) +{ + if (unlikely(arch_trace_is_compat_syscall(regs))) + return -1; + + return syscall_get_nr(task, regs); +} +#else +static inline int +trace_get_syscall_nr(struct task_struct *task, struct pt_regs *regs) +{ + return syscall_get_nr(task, regs); +} +#endif /* ARCH_TRACE_IGNORE_COMPAT_SYSCALLS */ + +static __init struct syscall_metadata * +find_syscall_meta(unsigned long syscall) +{ + struct syscall_metadata **start; + struct syscall_metadata **stop; + char str[KSYM_SYMBOL_LEN]; + + + start = __start_syscalls_metadata; + stop = __stop_syscalls_metadata; + kallsyms_lookup(syscall, NULL, NULL, NULL, str); + + if (arch_syscall_match_sym_name(str, "sys_ni_syscall")) + return NULL; + + for ( ; start < stop; start++) { + if ((*start)->name && arch_syscall_match_sym_name(str, (*start)->name)) + return *start; + } + return NULL; +} + +static struct syscall_metadata *syscall_nr_to_meta(int nr) +{ + if (!syscalls_metadata || nr >= NR_syscalls || nr < 0) + return NULL; + + return syscalls_metadata[nr]; +} -enum print_line_t -print_syscall_enter(struct trace_iterator *iter, int flags) +static enum print_line_t +print_syscall_enter(struct trace_iterator *iter, int flags, + struct trace_event *event) { struct trace_seq *s = &iter->seq; struct trace_entry *ent = iter->ent; @@ -35,40 +116,52 @@ print_syscall_enter(struct trace_iterator *iter, int flags) struct syscall_metadata *entry; int i, ret, syscall; - trace_assign_type(trace, ent); - + trace = (typeof(trace))ent; syscall = trace->nr; - entry = syscall_nr_to_meta(syscall); + if (!entry) goto end; + if (entry->enter_event->event.type != ent->type) { + WARN_ON_ONCE(1); + goto end; + } + ret = trace_seq_printf(s, "%s(", entry->name); if (!ret) return TRACE_TYPE_PARTIAL_LINE; for (i = 0; i < entry->nb_args; i++) { /* parameter types */ - if (syscalls_flags.val & TRACE_SYSCALLS_OPT_TYPES) { + if (trace_flags & TRACE_ITER_VERBOSE) { ret = trace_seq_printf(s, "%s ", entry->types[i]); if (!ret) return TRACE_TYPE_PARTIAL_LINE; } /* parameter values */ - ret = trace_seq_printf(s, "%s: %lx%s ", entry->args[i], + ret = trace_seq_printf(s, "%s: %lx%s", entry->args[i], trace->args[i], - i == entry->nb_args - 1 ? ")" : ","); + i == entry->nb_args - 1 ? "" : ", "); if (!ret) return TRACE_TYPE_PARTIAL_LINE; } + ret = trace_seq_putc(s, ')'); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + end: - trace_seq_printf(s, "\n"); + ret = trace_seq_putc(s, '\n'); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + return TRACE_TYPE_HANDLED; } -enum print_line_t -print_syscall_exit(struct trace_iterator *iter, int flags) +static enum print_line_t +print_syscall_exit(struct trace_iterator *iter, int flags, + struct trace_event *event) { struct trace_seq *s = &iter->seq; struct trace_entry *ent = iter->ent; @@ -77,16 +170,20 @@ print_syscall_exit(struct trace_iterator *iter, int flags) struct syscall_metadata *entry; int ret; - trace_assign_type(trace, ent); - + trace = (typeof(trace))ent; syscall = trace->nr; - entry = syscall_nr_to_meta(syscall); + if (!entry) { - trace_seq_printf(s, "\n"); + trace_seq_putc(s, '\n'); return TRACE_TYPE_HANDLED; } + if (entry->exit_event->event.type != ent->type) { + WARN_ON_ONCE(1); + return TRACE_TYPE_UNHANDLED; + } + ret = trace_seq_printf(s, "%s -> 0x%lx\n", entry->name, trace->ret); if (!ret) @@ -95,62 +192,137 @@ print_syscall_exit(struct trace_iterator *iter, int flags) return TRACE_TYPE_HANDLED; } -void start_ftrace_syscalls(void) +extern char *__bad_type_size(void); + +#define SYSCALL_FIELD(type, name) \ + sizeof(type) != sizeof(trace.name) ? \ + __bad_type_size() : \ + #type, #name, offsetof(typeof(trace), name), \ + sizeof(trace.name), is_signed_type(type) + +static int __init +__set_enter_print_fmt(struct syscall_metadata *entry, char *buf, int len) { - unsigned long flags; - struct task_struct *g, *t; + int i; + int pos = 0; - mutex_lock(&syscall_trace_lock); + /* When len=0, we just calculate the needed length */ +#define LEN_OR_ZERO (len ? len - pos : 0) - /* Don't enable the flag on the tasks twice */ - if (++refcount != 1) - goto unlock; + pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); + for (i = 0; i < entry->nb_args; i++) { + pos += snprintf(buf + pos, LEN_OR_ZERO, "%s: 0x%%0%zulx%s", + entry->args[i], sizeof(unsigned long), + i == entry->nb_args - 1 ? "" : ", "); + } + pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); - arch_init_ftrace_syscalls(); - read_lock_irqsave(&tasklist_lock, flags); + for (i = 0; i < entry->nb_args; i++) { + pos += snprintf(buf + pos, LEN_OR_ZERO, + ", ((unsigned long)(REC->%s))", entry->args[i]); + } - do_each_thread(g, t) { - set_tsk_thread_flag(t, TIF_SYSCALL_FTRACE); - } while_each_thread(g, t); +#undef LEN_OR_ZERO - read_unlock_irqrestore(&tasklist_lock, flags); + /* return the length of print_fmt */ + return pos; +} -unlock: - mutex_unlock(&syscall_trace_lock); +static int __init set_syscall_print_fmt(struct ftrace_event_call *call) +{ + char *print_fmt; + int len; + struct syscall_metadata *entry = call->data; + + if (entry->enter_event != call) { + call->print_fmt = "\"0x%lx\", REC->ret"; + return 0; + } + + /* First: called with 0 length to calculate the needed length */ + len = __set_enter_print_fmt(entry, NULL, 0); + + print_fmt = kmalloc(len + 1, GFP_KERNEL); + if (!print_fmt) + return -ENOMEM; + + /* Second: actually write the @print_fmt */ + __set_enter_print_fmt(entry, print_fmt, len + 1); + call->print_fmt = print_fmt; + + return 0; } -void stop_ftrace_syscalls(void) +static void __init free_syscall_print_fmt(struct ftrace_event_call *call) { - unsigned long flags; - struct task_struct *g, *t; + struct syscall_metadata *entry = call->data; - mutex_lock(&syscall_trace_lock); + if (entry->enter_event == call) + kfree(call->print_fmt); +} - /* There are perhaps still some users */ - if (--refcount) - goto unlock; +static int __init syscall_enter_define_fields(struct ftrace_event_call *call) +{ + struct syscall_trace_enter trace; + struct syscall_metadata *meta = call->data; + int ret; + int i; + int offset = offsetof(typeof(trace), args); + + ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER); + if (ret) + return ret; + + for (i = 0; i < meta->nb_args; i++) { + ret = trace_define_field(call, meta->types[i], + meta->args[i], offset, + sizeof(unsigned long), 0, + FILTER_OTHER); + offset += sizeof(unsigned long); + } - read_lock_irqsave(&tasklist_lock, flags); + return ret; +} - do_each_thread(g, t) { - clear_tsk_thread_flag(t, TIF_SYSCALL_FTRACE); - } while_each_thread(g, t); +static int __init syscall_exit_define_fields(struct ftrace_event_call *call) +{ + struct syscall_trace_exit trace; + int ret; - read_unlock_irqrestore(&tasklist_lock, flags); + ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER); + if (ret) + return ret; -unlock: - mutex_unlock(&syscall_trace_lock); + ret = trace_define_field(call, SYSCALL_FIELD(long, ret), + FILTER_OTHER); + + return ret; } -void ftrace_syscall_enter(struct pt_regs *regs) +static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id) { + struct trace_array *tr = data; + struct ftrace_event_file *ftrace_file; struct syscall_trace_enter *entry; struct syscall_metadata *sys_data; struct ring_buffer_event *event; - int size; + struct ring_buffer *buffer; + unsigned long irq_flags; + int pc; int syscall_nr; + int size; + + syscall_nr = trace_get_syscall_nr(current, regs); + if (syscall_nr < 0) + return; - syscall_nr = syscall_get_nr(current, regs); + /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE) */ + ftrace_file = rcu_dereference_sched(tr->enter_syscall_files[syscall_nr]); + if (!ftrace_file) + return; + + if (ftrace_trigger_soft_disabled(ftrace_file)) + return; sys_data = syscall_nr_to_meta(syscall_nr); if (!sys_data) @@ -158,8 +330,12 @@ void ftrace_syscall_enter(struct pt_regs *regs) size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args; - event = trace_current_buffer_lock_reserve(TRACE_SYSCALL_ENTER, size, - 0, 0); + local_save_flags(irq_flags); + pc = preempt_count(); + + buffer = tr->trace_buffer.buffer; + event = trace_buffer_lock_reserve(buffer, + sys_data->enter_event->event.type, size, irq_flags, pc); if (!event) return; @@ -167,25 +343,45 @@ void ftrace_syscall_enter(struct pt_regs *regs) entry->nr = syscall_nr; syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args); - trace_current_buffer_unlock_commit(event, 0, 0); - trace_wake_up(); + event_trigger_unlock_commit(ftrace_file, buffer, event, entry, + irq_flags, pc); } -void ftrace_syscall_exit(struct pt_regs *regs) +static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret) { + struct trace_array *tr = data; + struct ftrace_event_file *ftrace_file; struct syscall_trace_exit *entry; struct syscall_metadata *sys_data; struct ring_buffer_event *event; + struct ring_buffer *buffer; + unsigned long irq_flags; + int pc; int syscall_nr; - syscall_nr = syscall_get_nr(current, regs); + syscall_nr = trace_get_syscall_nr(current, regs); + if (syscall_nr < 0) + return; + + /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE()) */ + ftrace_file = rcu_dereference_sched(tr->exit_syscall_files[syscall_nr]); + if (!ftrace_file) + return; + + if (ftrace_trigger_soft_disabled(ftrace_file)) + return; sys_data = syscall_nr_to_meta(syscall_nr); if (!sys_data) return; - event = trace_current_buffer_lock_reserve(TRACE_SYSCALL_EXIT, - sizeof(*entry), 0, 0); + local_save_flags(irq_flags); + pc = preempt_count(); + + buffer = tr->trace_buffer.buffer; + event = trace_buffer_lock_reserve(buffer, + sys_data->exit_event->event.type, sizeof(*entry), + irq_flags, pc); if (!event) return; @@ -193,58 +389,374 @@ void ftrace_syscall_exit(struct pt_regs *regs) entry->nr = syscall_nr; entry->ret = syscall_get_return_value(current, regs); - trace_current_buffer_unlock_commit(event, 0, 0); - trace_wake_up(); + event_trigger_unlock_commit(ftrace_file, buffer, event, entry, + irq_flags, pc); } -static int init_syscall_tracer(struct trace_array *tr) +static int reg_event_syscall_enter(struct ftrace_event_file *file, + struct ftrace_event_call *call) { - start_ftrace_syscalls(); + struct trace_array *tr = file->tr; + int ret = 0; + int num; - return 0; + num = ((struct syscall_metadata *)call->data)->syscall_nr; + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) + return -ENOSYS; + mutex_lock(&syscall_trace_lock); + if (!tr->sys_refcount_enter) + ret = register_trace_sys_enter(ftrace_syscall_enter, tr); + if (!ret) { + rcu_assign_pointer(tr->enter_syscall_files[num], file); + tr->sys_refcount_enter++; + } + mutex_unlock(&syscall_trace_lock); + return ret; +} + +static void unreg_event_syscall_enter(struct ftrace_event_file *file, + struct ftrace_event_call *call) +{ + struct trace_array *tr = file->tr; + int num; + + num = ((struct syscall_metadata *)call->data)->syscall_nr; + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) + return; + mutex_lock(&syscall_trace_lock); + tr->sys_refcount_enter--; + rcu_assign_pointer(tr->enter_syscall_files[num], NULL); + if (!tr->sys_refcount_enter) + unregister_trace_sys_enter(ftrace_syscall_enter, tr); + mutex_unlock(&syscall_trace_lock); } -static void reset_syscall_tracer(struct trace_array *tr) +static int reg_event_syscall_exit(struct ftrace_event_file *file, + struct ftrace_event_call *call) { - stop_ftrace_syscalls(); - tracing_reset_online_cpus(tr); + struct trace_array *tr = file->tr; + int ret = 0; + int num; + + num = ((struct syscall_metadata *)call->data)->syscall_nr; + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) + return -ENOSYS; + mutex_lock(&syscall_trace_lock); + if (!tr->sys_refcount_exit) + ret = register_trace_sys_exit(ftrace_syscall_exit, tr); + if (!ret) { + rcu_assign_pointer(tr->exit_syscall_files[num], file); + tr->sys_refcount_exit++; + } + mutex_unlock(&syscall_trace_lock); + return ret; } -static struct trace_event syscall_enter_event = { - .type = TRACE_SYSCALL_ENTER, +static void unreg_event_syscall_exit(struct ftrace_event_file *file, + struct ftrace_event_call *call) +{ + struct trace_array *tr = file->tr; + int num; + + num = ((struct syscall_metadata *)call->data)->syscall_nr; + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) + return; + mutex_lock(&syscall_trace_lock); + tr->sys_refcount_exit--; + rcu_assign_pointer(tr->exit_syscall_files[num], NULL); + if (!tr->sys_refcount_exit) + unregister_trace_sys_exit(ftrace_syscall_exit, tr); + mutex_unlock(&syscall_trace_lock); +} + +static int __init init_syscall_trace(struct ftrace_event_call *call) +{ + int id; + int num; + + num = ((struct syscall_metadata *)call->data)->syscall_nr; + if (num < 0 || num >= NR_syscalls) { + pr_debug("syscall %s metadata not mapped, disabling ftrace event\n", + ((struct syscall_metadata *)call->data)->name); + return -ENOSYS; + } + + if (set_syscall_print_fmt(call) < 0) + return -ENOMEM; + + id = trace_event_raw_init(call); + + if (id < 0) { + free_syscall_print_fmt(call); + return id; + } + + return id; +} + +struct trace_event_functions enter_syscall_print_funcs = { .trace = print_syscall_enter, }; -static struct trace_event syscall_exit_event = { - .type = TRACE_SYSCALL_EXIT, +struct trace_event_functions exit_syscall_print_funcs = { .trace = print_syscall_exit, }; -static struct tracer syscall_tracer __read_mostly = { - .name = "syscall", - .init = init_syscall_tracer, - .reset = reset_syscall_tracer, - .flags = &syscalls_flags, +struct ftrace_event_class __refdata event_class_syscall_enter = { + .system = "syscalls", + .reg = syscall_enter_register, + .define_fields = syscall_enter_define_fields, + .get_fields = syscall_get_enter_fields, + .raw_init = init_syscall_trace, }; -__init int register_ftrace_syscalls(void) +struct ftrace_event_class __refdata event_class_syscall_exit = { + .system = "syscalls", + .reg = syscall_exit_register, + .define_fields = syscall_exit_define_fields, + .fields = LIST_HEAD_INIT(event_class_syscall_exit.fields), + .raw_init = init_syscall_trace, +}; + +unsigned long __init __weak arch_syscall_addr(int nr) { - int ret; + return (unsigned long)sys_call_table[nr]; +} - ret = register_ftrace_event(&syscall_enter_event); - if (!ret) { - printk(KERN_WARNING "event %d failed to register\n", - syscall_enter_event.type); - WARN_ON_ONCE(1); +static int __init init_ftrace_syscalls(void) +{ + struct syscall_metadata *meta; + unsigned long addr; + int i; + + syscalls_metadata = kcalloc(NR_syscalls, sizeof(*syscalls_metadata), + GFP_KERNEL); + if (!syscalls_metadata) { + WARN_ON(1); + return -ENOMEM; } - ret = register_ftrace_event(&syscall_exit_event); - if (!ret) { - printk(KERN_WARNING "event %d failed to register\n", - syscall_exit_event.type); - WARN_ON_ONCE(1); + for (i = 0; i < NR_syscalls; i++) { + addr = arch_syscall_addr(i); + meta = find_syscall_meta(addr); + if (!meta) + continue; + + meta->syscall_nr = i; + syscalls_metadata[i] = meta; + } + + return 0; +} +early_initcall(init_ftrace_syscalls); + +#ifdef CONFIG_PERF_EVENTS + +static DECLARE_BITMAP(enabled_perf_enter_syscalls, NR_syscalls); +static DECLARE_BITMAP(enabled_perf_exit_syscalls, NR_syscalls); +static int sys_perf_refcount_enter; +static int sys_perf_refcount_exit; + +static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id) +{ + struct syscall_metadata *sys_data; + struct syscall_trace_enter *rec; + struct hlist_head *head; + int syscall_nr; + int rctx; + int size; + + syscall_nr = trace_get_syscall_nr(current, regs); + if (syscall_nr < 0) + return; + if (!test_bit(syscall_nr, enabled_perf_enter_syscalls)) + return; + + sys_data = syscall_nr_to_meta(syscall_nr); + if (!sys_data) + return; + + head = this_cpu_ptr(sys_data->enter_event->perf_events); + if (hlist_empty(head)) + return; + + /* get the size after alignment with the u32 buffer size field */ + size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec); + size = ALIGN(size + sizeof(u32), sizeof(u64)); + size -= sizeof(u32); + + rec = (struct syscall_trace_enter *)perf_trace_buf_prepare(size, + sys_data->enter_event->event.type, regs, &rctx); + if (!rec) + return; + + rec->nr = syscall_nr; + syscall_get_arguments(current, regs, 0, sys_data->nb_args, + (unsigned long *)&rec->args); + perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL); +} + +static int perf_sysenter_enable(struct ftrace_event_call *call) +{ + int ret = 0; + int num; + + num = ((struct syscall_metadata *)call->data)->syscall_nr; + + mutex_lock(&syscall_trace_lock); + if (!sys_perf_refcount_enter) + ret = register_trace_sys_enter(perf_syscall_enter, NULL); + if (ret) { + pr_info("event trace: Could not activate" + "syscall entry trace point"); + } else { + set_bit(num, enabled_perf_enter_syscalls); + sys_perf_refcount_enter++; } + mutex_unlock(&syscall_trace_lock); + return ret; +} + +static void perf_sysenter_disable(struct ftrace_event_call *call) +{ + int num; + + num = ((struct syscall_metadata *)call->data)->syscall_nr; + + mutex_lock(&syscall_trace_lock); + sys_perf_refcount_enter--; + clear_bit(num, enabled_perf_enter_syscalls); + if (!sys_perf_refcount_enter) + unregister_trace_sys_enter(perf_syscall_enter, NULL); + mutex_unlock(&syscall_trace_lock); +} + +static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret) +{ + struct syscall_metadata *sys_data; + struct syscall_trace_exit *rec; + struct hlist_head *head; + int syscall_nr; + int rctx; + int size; + + syscall_nr = trace_get_syscall_nr(current, regs); + if (syscall_nr < 0) + return; + if (!test_bit(syscall_nr, enabled_perf_exit_syscalls)) + return; + + sys_data = syscall_nr_to_meta(syscall_nr); + if (!sys_data) + return; + + head = this_cpu_ptr(sys_data->exit_event->perf_events); + if (hlist_empty(head)) + return; + + /* We can probably do that at build time */ + size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64)); + size -= sizeof(u32); + + rec = (struct syscall_trace_exit *)perf_trace_buf_prepare(size, + sys_data->exit_event->event.type, regs, &rctx); + if (!rec) + return; - return register_tracer(&syscall_tracer); + rec->nr = syscall_nr; + rec->ret = syscall_get_return_value(current, regs); + perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL); +} + +static int perf_sysexit_enable(struct ftrace_event_call *call) +{ + int ret = 0; + int num; + + num = ((struct syscall_metadata *)call->data)->syscall_nr; + + mutex_lock(&syscall_trace_lock); + if (!sys_perf_refcount_exit) + ret = register_trace_sys_exit(perf_syscall_exit, NULL); + if (ret) { + pr_info("event trace: Could not activate" + "syscall exit trace point"); + } else { + set_bit(num, enabled_perf_exit_syscalls); + sys_perf_refcount_exit++; + } + mutex_unlock(&syscall_trace_lock); + return ret; +} + +static void perf_sysexit_disable(struct ftrace_event_call *call) +{ + int num; + + num = ((struct syscall_metadata *)call->data)->syscall_nr; + + mutex_lock(&syscall_trace_lock); + sys_perf_refcount_exit--; + clear_bit(num, enabled_perf_exit_syscalls); + if (!sys_perf_refcount_exit) + unregister_trace_sys_exit(perf_syscall_exit, NULL); + mutex_unlock(&syscall_trace_lock); +} + +#endif /* CONFIG_PERF_EVENTS */ + +static int syscall_enter_register(struct ftrace_event_call *event, + enum trace_reg type, void *data) +{ + struct ftrace_event_file *file = data; + + switch (type) { + case TRACE_REG_REGISTER: + return reg_event_syscall_enter(file, event); + case TRACE_REG_UNREGISTER: + unreg_event_syscall_enter(file, event); + return 0; + +#ifdef CONFIG_PERF_EVENTS + case TRACE_REG_PERF_REGISTER: + return perf_sysenter_enable(event); + case TRACE_REG_PERF_UNREGISTER: + perf_sysenter_disable(event); + return 0; + case TRACE_REG_PERF_OPEN: + case TRACE_REG_PERF_CLOSE: + case TRACE_REG_PERF_ADD: + case TRACE_REG_PERF_DEL: + return 0; +#endif + } + return 0; +} + +static int syscall_exit_register(struct ftrace_event_call *event, + enum trace_reg type, void *data) +{ + struct ftrace_event_file *file = data; + + switch (type) { + case TRACE_REG_REGISTER: + return reg_event_syscall_exit(file, event); + case TRACE_REG_UNREGISTER: + unreg_event_syscall_exit(file, event); + return 0; + +#ifdef CONFIG_PERF_EVENTS + case TRACE_REG_PERF_REGISTER: + return perf_sysexit_enable(event); + case TRACE_REG_PERF_UNREGISTER: + perf_sysexit_disable(event); + return 0; + case TRACE_REG_PERF_OPEN: + case TRACE_REG_PERF_CLOSE: + case TRACE_REG_PERF_ADD: + case TRACE_REG_PERF_DEL: + return 0; +#endif + } + return 0; } -device_initcall(register_ftrace_syscalls); diff --git a/kernel/trace/trace_sysprof.c b/kernel/trace/trace_sysprof.c deleted file mode 100644 index f6693969287..00000000000 --- a/kernel/trace/trace_sysprof.c +++ /dev/null @@ -1,328 +0,0 @@ -/* - * trace stack traces - * - * Copyright (C) 2004-2008, Soeren Sandmann - * Copyright (C) 2007 Steven Rostedt <srostedt@redhat.com> - * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> - */ -#include <linux/kallsyms.h> -#include <linux/debugfs.h> -#include <linux/hrtimer.h> -#include <linux/uaccess.h> -#include <linux/ftrace.h> -#include <linux/module.h> -#include <linux/irq.h> -#include <linux/fs.h> - -#include <asm/stacktrace.h> - -#include "trace.h" - -static struct trace_array *sysprof_trace; -static int __read_mostly tracer_enabled; - -/* - * 1 msec sample interval by default: - */ -static unsigned long sample_period = 1000000; -static const unsigned int sample_max_depth = 512; - -static DEFINE_MUTEX(sample_timer_lock); -/* - * Per CPU hrtimers that do the profiling: - */ -static DEFINE_PER_CPU(struct hrtimer, stack_trace_hrtimer); - -struct stack_frame { - const void __user *next_fp; - unsigned long return_address; -}; - -static int copy_stack_frame(const void __user *fp, struct stack_frame *frame) -{ - int ret; - - if (!access_ok(VERIFY_READ, fp, sizeof(*frame))) - return 0; - - ret = 1; - pagefault_disable(); - if (__copy_from_user_inatomic(frame, fp, sizeof(*frame))) - ret = 0; - pagefault_enable(); - - return ret; -} - -struct backtrace_info { - struct trace_array_cpu *data; - struct trace_array *tr; - int pos; -}; - -static void -backtrace_warning_symbol(void *data, char *msg, unsigned long symbol) -{ - /* Ignore warnings */ -} - -static void backtrace_warning(void *data, char *msg) -{ - /* Ignore warnings */ -} - -static int backtrace_stack(void *data, char *name) -{ - /* Don't bother with IRQ stacks for now */ - return -1; -} - -static void backtrace_address(void *data, unsigned long addr, int reliable) -{ - struct backtrace_info *info = data; - - if (info->pos < sample_max_depth && reliable) { - __trace_special(info->tr, info->data, 1, addr, 0); - - info->pos++; - } -} - -static const struct stacktrace_ops backtrace_ops = { - .warning = backtrace_warning, - .warning_symbol = backtrace_warning_symbol, - .stack = backtrace_stack, - .address = backtrace_address, -}; - -static int -trace_kernel(struct pt_regs *regs, struct trace_array *tr, - struct trace_array_cpu *data) -{ - struct backtrace_info info; - unsigned long bp; - char *stack; - - info.tr = tr; - info.data = data; - info.pos = 1; - - __trace_special(info.tr, info.data, 1, regs->ip, 0); - - stack = ((char *)regs + sizeof(struct pt_regs)); -#ifdef CONFIG_FRAME_POINTER - bp = regs->bp; -#else - bp = 0; -#endif - - dump_trace(NULL, regs, (void *)stack, bp, &backtrace_ops, &info); - - return info.pos; -} - -static void timer_notify(struct pt_regs *regs, int cpu) -{ - struct trace_array_cpu *data; - struct stack_frame frame; - struct trace_array *tr; - const void __user *fp; - int is_user; - int i; - - if (!regs) - return; - - tr = sysprof_trace; - data = tr->data[cpu]; - is_user = user_mode(regs); - - if (!current || current->pid == 0) - return; - - if (is_user && current->state != TASK_RUNNING) - return; - - __trace_special(tr, data, 0, 0, current->pid); - - if (!is_user) - i = trace_kernel(regs, tr, data); - else - i = 0; - - /* - * Trace user stack if we are not a kernel thread - */ - if (current->mm && i < sample_max_depth) { - regs = (struct pt_regs *)current->thread.sp0 - 1; - - fp = (void __user *)regs->bp; - - __trace_special(tr, data, 2, regs->ip, 0); - - while (i < sample_max_depth) { - frame.next_fp = NULL; - frame.return_address = 0; - if (!copy_stack_frame(fp, &frame)) - break; - if ((unsigned long)fp < regs->sp) - break; - - __trace_special(tr, data, 2, frame.return_address, - (unsigned long)fp); - fp = frame.next_fp; - - i++; - } - - } - - /* - * Special trace entry if we overflow the max depth: - */ - if (i == sample_max_depth) - __trace_special(tr, data, -1, -1, -1); - - __trace_special(tr, data, 3, current->pid, i); -} - -static enum hrtimer_restart stack_trace_timer_fn(struct hrtimer *hrtimer) -{ - /* trace here */ - timer_notify(get_irq_regs(), smp_processor_id()); - - hrtimer_forward_now(hrtimer, ns_to_ktime(sample_period)); - - return HRTIMER_RESTART; -} - -static void start_stack_timer(void *unused) -{ - struct hrtimer *hrtimer = &__get_cpu_var(stack_trace_hrtimer); - - hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - hrtimer->function = stack_trace_timer_fn; - - hrtimer_start(hrtimer, ns_to_ktime(sample_period), - HRTIMER_MODE_REL_PINNED); -} - -static void start_stack_timers(void) -{ - on_each_cpu(start_stack_timer, NULL, 1); -} - -static void stop_stack_timer(int cpu) -{ - struct hrtimer *hrtimer = &per_cpu(stack_trace_hrtimer, cpu); - - hrtimer_cancel(hrtimer); -} - -static void stop_stack_timers(void) -{ - int cpu; - - for_each_online_cpu(cpu) - stop_stack_timer(cpu); -} - -static void stop_stack_trace(struct trace_array *tr) -{ - mutex_lock(&sample_timer_lock); - stop_stack_timers(); - tracer_enabled = 0; - mutex_unlock(&sample_timer_lock); -} - -static int stack_trace_init(struct trace_array *tr) -{ - sysprof_trace = tr; - - tracing_start_cmdline_record(); - - mutex_lock(&sample_timer_lock); - start_stack_timers(); - tracer_enabled = 1; - mutex_unlock(&sample_timer_lock); - return 0; -} - -static void stack_trace_reset(struct trace_array *tr) -{ - tracing_stop_cmdline_record(); - stop_stack_trace(tr); -} - -static struct tracer stack_trace __read_mostly = -{ - .name = "sysprof", - .init = stack_trace_init, - .reset = stack_trace_reset, -#ifdef CONFIG_FTRACE_SELFTEST - .selftest = trace_selftest_startup_sysprof, -#endif -}; - -__init static int init_stack_trace(void) -{ - return register_tracer(&stack_trace); -} -device_initcall(init_stack_trace); - -#define MAX_LONG_DIGITS 22 - -static ssize_t -sysprof_sample_read(struct file *filp, char __user *ubuf, - size_t cnt, loff_t *ppos) -{ - char buf[MAX_LONG_DIGITS]; - int r; - - r = sprintf(buf, "%ld\n", nsecs_to_usecs(sample_period)); - - return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); -} - -static ssize_t -sysprof_sample_write(struct file *filp, const char __user *ubuf, - size_t cnt, loff_t *ppos) -{ - char buf[MAX_LONG_DIGITS]; - unsigned long val; - - if (cnt > MAX_LONG_DIGITS-1) - cnt = MAX_LONG_DIGITS-1; - - if (copy_from_user(&buf, ubuf, cnt)) - return -EFAULT; - - buf[cnt] = 0; - - val = simple_strtoul(buf, NULL, 10); - /* - * Enforce a minimum sample period of 100 usecs: - */ - if (val < 100) - val = 100; - - mutex_lock(&sample_timer_lock); - stop_stack_timers(); - sample_period = val * 1000; - start_stack_timers(); - mutex_unlock(&sample_timer_lock); - - return cnt; -} - -static const struct file_operations sysprof_sample_fops = { - .read = sysprof_sample_read, - .write = sysprof_sample_write, -}; - -void init_tracer_sysprof_debugfs(struct dentry *d_tracer) -{ - - trace_create_file("sysprof_sample_period", 0644, - d_tracer, NULL, &sysprof_sample_fops); -} diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c new file mode 100644 index 00000000000..3c9b97e6b1f --- /dev/null +++ b/kernel/trace/trace_uprobe.c @@ -0,0 +1,1340 @@ +/* + * uprobes-based tracing events + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * Copyright (C) IBM Corporation, 2010-2012 + * Author: Srikar Dronamraju <srikar@linux.vnet.ibm.com> + */ + +#include <linux/module.h> +#include <linux/uaccess.h> +#include <linux/uprobes.h> +#include <linux/namei.h> +#include <linux/string.h> + +#include "trace_probe.h" + +#define UPROBE_EVENT_SYSTEM "uprobes" + +struct uprobe_trace_entry_head { + struct trace_entry ent; + unsigned long vaddr[]; +}; + +#define SIZEOF_TRACE_ENTRY(is_return) \ + (sizeof(struct uprobe_trace_entry_head) + \ + sizeof(unsigned long) * (is_return ? 2 : 1)) + +#define DATAOF_TRACE_ENTRY(entry, is_return) \ + ((void*)(entry) + SIZEOF_TRACE_ENTRY(is_return)) + +struct trace_uprobe_filter { + rwlock_t rwlock; + int nr_systemwide; + struct list_head perf_events; +}; + +/* + * uprobe event core functions + */ +struct trace_uprobe { + struct list_head list; + struct trace_uprobe_filter filter; + struct uprobe_consumer consumer; + struct inode *inode; + char *filename; + unsigned long offset; + unsigned long nhit; + struct trace_probe tp; +}; + +#define SIZEOF_TRACE_UPROBE(n) \ + (offsetof(struct trace_uprobe, tp.args) + \ + (sizeof(struct probe_arg) * (n))) + +static int register_uprobe_event(struct trace_uprobe *tu); +static int unregister_uprobe_event(struct trace_uprobe *tu); + +static DEFINE_MUTEX(uprobe_lock); +static LIST_HEAD(uprobe_list); + +struct uprobe_dispatch_data { + struct trace_uprobe *tu; + unsigned long bp_addr; +}; + +static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs); +static int uretprobe_dispatcher(struct uprobe_consumer *con, + unsigned long func, struct pt_regs *regs); + +#ifdef CONFIG_STACK_GROWSUP +static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n) +{ + return addr - (n * sizeof(long)); +} +#else +static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n) +{ + return addr + (n * sizeof(long)); +} +#endif + +static unsigned long get_user_stack_nth(struct pt_regs *regs, unsigned int n) +{ + unsigned long ret; + unsigned long addr = user_stack_pointer(regs); + + addr = adjust_stack_addr(addr, n); + + if (copy_from_user(&ret, (void __force __user *) addr, sizeof(ret))) + return 0; + + return ret; +} + +/* + * Uprobes-specific fetch functions + */ +#define DEFINE_FETCH_stack(type) \ +static void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs, \ + void *offset, void *dest) \ +{ \ + *(type *)dest = (type)get_user_stack_nth(regs, \ + ((unsigned long)offset)); \ +} +DEFINE_BASIC_FETCH_FUNCS(stack) +/* No string on the stack entry */ +#define fetch_stack_string NULL +#define fetch_stack_string_size NULL + +#define DEFINE_FETCH_memory(type) \ +static void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs, \ + void *addr, void *dest) \ +{ \ + type retval; \ + void __user *vaddr = (void __force __user *) addr; \ + \ + if (copy_from_user(&retval, vaddr, sizeof(type))) \ + *(type *)dest = 0; \ + else \ + *(type *) dest = retval; \ +} +DEFINE_BASIC_FETCH_FUNCS(memory) +/* + * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max + * length and relative data location. + */ +static void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs, + void *addr, void *dest) +{ + long ret; + u32 rloc = *(u32 *)dest; + int maxlen = get_rloc_len(rloc); + u8 *dst = get_rloc_data(dest); + void __user *src = (void __force __user *) addr; + + if (!maxlen) + return; + + ret = strncpy_from_user(dst, src, maxlen); + + if (ret < 0) { /* Failed to fetch string */ + ((u8 *)get_rloc_data(dest))[0] = '\0'; + *(u32 *)dest = make_data_rloc(0, get_rloc_offs(rloc)); + } else { + *(u32 *)dest = make_data_rloc(ret, get_rloc_offs(rloc)); + } +} + +static void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs, + void *addr, void *dest) +{ + int len; + void __user *vaddr = (void __force __user *) addr; + + len = strnlen_user(vaddr, MAX_STRING_SIZE); + + if (len == 0 || len > MAX_STRING_SIZE) /* Failed to check length */ + *(u32 *)dest = 0; + else + *(u32 *)dest = len; +} + +static unsigned long translate_user_vaddr(void *file_offset) +{ + unsigned long base_addr; + struct uprobe_dispatch_data *udd; + + udd = (void *) current->utask->vaddr; + + base_addr = udd->bp_addr - udd->tu->offset; + return base_addr + (unsigned long)file_offset; +} + +#define DEFINE_FETCH_file_offset(type) \ +static void FETCH_FUNC_NAME(file_offset, type)(struct pt_regs *regs, \ + void *offset, void *dest)\ +{ \ + void *vaddr = (void *)translate_user_vaddr(offset); \ + \ + FETCH_FUNC_NAME(memory, type)(regs, vaddr, dest); \ +} +DEFINE_BASIC_FETCH_FUNCS(file_offset) +DEFINE_FETCH_file_offset(string) +DEFINE_FETCH_file_offset(string_size) + +/* Fetch type information table */ +const struct fetch_type uprobes_fetch_type_table[] = { + /* Special types */ + [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string, + sizeof(u32), 1, "__data_loc char[]"), + [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32, + string_size, sizeof(u32), 0, "u32"), + /* Basic types */ + ASSIGN_FETCH_TYPE(u8, u8, 0), + ASSIGN_FETCH_TYPE(u16, u16, 0), + ASSIGN_FETCH_TYPE(u32, u32, 0), + ASSIGN_FETCH_TYPE(u64, u64, 0), + ASSIGN_FETCH_TYPE(s8, u8, 1), + ASSIGN_FETCH_TYPE(s16, u16, 1), + ASSIGN_FETCH_TYPE(s32, u32, 1), + ASSIGN_FETCH_TYPE(s64, u64, 1), + + ASSIGN_FETCH_TYPE_END +}; + +static inline void init_trace_uprobe_filter(struct trace_uprobe_filter *filter) +{ + rwlock_init(&filter->rwlock); + filter->nr_systemwide = 0; + INIT_LIST_HEAD(&filter->perf_events); +} + +static inline bool uprobe_filter_is_empty(struct trace_uprobe_filter *filter) +{ + return !filter->nr_systemwide && list_empty(&filter->perf_events); +} + +static inline bool is_ret_probe(struct trace_uprobe *tu) +{ + return tu->consumer.ret_handler != NULL; +} + +/* + * Allocate new trace_uprobe and initialize it (including uprobes). + */ +static struct trace_uprobe * +alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret) +{ + struct trace_uprobe *tu; + + if (!event || !is_good_name(event)) + return ERR_PTR(-EINVAL); + + if (!group || !is_good_name(group)) + return ERR_PTR(-EINVAL); + + tu = kzalloc(SIZEOF_TRACE_UPROBE(nargs), GFP_KERNEL); + if (!tu) + return ERR_PTR(-ENOMEM); + + tu->tp.call.class = &tu->tp.class; + tu->tp.call.name = kstrdup(event, GFP_KERNEL); + if (!tu->tp.call.name) + goto error; + + tu->tp.class.system = kstrdup(group, GFP_KERNEL); + if (!tu->tp.class.system) + goto error; + + INIT_LIST_HEAD(&tu->list); + INIT_LIST_HEAD(&tu->tp.files); + tu->consumer.handler = uprobe_dispatcher; + if (is_ret) + tu->consumer.ret_handler = uretprobe_dispatcher; + init_trace_uprobe_filter(&tu->filter); + tu->tp.call.flags |= TRACE_EVENT_FL_USE_CALL_FILTER; + return tu; + +error: + kfree(tu->tp.call.name); + kfree(tu); + + return ERR_PTR(-ENOMEM); +} + +static void free_trace_uprobe(struct trace_uprobe *tu) +{ + int i; + + for (i = 0; i < tu->tp.nr_args; i++) + traceprobe_free_probe_arg(&tu->tp.args[i]); + + iput(tu->inode); + kfree(tu->tp.call.class->system); + kfree(tu->tp.call.name); + kfree(tu->filename); + kfree(tu); +} + +static struct trace_uprobe *find_probe_event(const char *event, const char *group) +{ + struct trace_uprobe *tu; + + list_for_each_entry(tu, &uprobe_list, list) + if (strcmp(ftrace_event_name(&tu->tp.call), event) == 0 && + strcmp(tu->tp.call.class->system, group) == 0) + return tu; + + return NULL; +} + +/* Unregister a trace_uprobe and probe_event: call with locking uprobe_lock */ +static int unregister_trace_uprobe(struct trace_uprobe *tu) +{ + int ret; + + ret = unregister_uprobe_event(tu); + if (ret) + return ret; + + list_del(&tu->list); + free_trace_uprobe(tu); + return 0; +} + +/* Register a trace_uprobe and probe_event */ +static int register_trace_uprobe(struct trace_uprobe *tu) +{ + struct trace_uprobe *old_tu; + int ret; + + mutex_lock(&uprobe_lock); + + /* register as an event */ + old_tu = find_probe_event(ftrace_event_name(&tu->tp.call), + tu->tp.call.class->system); + if (old_tu) { + /* delete old event */ + ret = unregister_trace_uprobe(old_tu); + if (ret) + goto end; + } + + ret = register_uprobe_event(tu); + if (ret) { + pr_warning("Failed to register probe event(%d)\n", ret); + goto end; + } + + list_add_tail(&tu->list, &uprobe_list); + +end: + mutex_unlock(&uprobe_lock); + + return ret; +} + +/* + * Argument syntax: + * - Add uprobe: p|r[:[GRP/]EVENT] PATH:OFFSET [FETCHARGS] + * + * - Remove uprobe: -:[GRP/]EVENT + */ +static int create_trace_uprobe(int argc, char **argv) +{ + struct trace_uprobe *tu; + struct inode *inode; + char *arg, *event, *group, *filename; + char buf[MAX_EVENT_NAME_LEN]; + struct path path; + unsigned long offset; + bool is_delete, is_return; + int i, ret; + + inode = NULL; + ret = 0; + is_delete = false; + is_return = false; + event = NULL; + group = NULL; + + /* argc must be >= 1 */ + if (argv[0][0] == '-') + is_delete = true; + else if (argv[0][0] == 'r') + is_return = true; + else if (argv[0][0] != 'p') { + pr_info("Probe definition must be started with 'p', 'r' or '-'.\n"); + return -EINVAL; + } + + if (argv[0][1] == ':') { + event = &argv[0][2]; + arg = strchr(event, '/'); + + if (arg) { + group = event; + event = arg + 1; + event[-1] = '\0'; + + if (strlen(group) == 0) { + pr_info("Group name is not specified\n"); + return -EINVAL; + } + } + if (strlen(event) == 0) { + pr_info("Event name is not specified\n"); + return -EINVAL; + } + } + if (!group) + group = UPROBE_EVENT_SYSTEM; + + if (is_delete) { + int ret; + + if (!event) { + pr_info("Delete command needs an event name.\n"); + return -EINVAL; + } + mutex_lock(&uprobe_lock); + tu = find_probe_event(event, group); + + if (!tu) { + mutex_unlock(&uprobe_lock); + pr_info("Event %s/%s doesn't exist.\n", group, event); + return -ENOENT; + } + /* delete an event */ + ret = unregister_trace_uprobe(tu); + mutex_unlock(&uprobe_lock); + return ret; + } + + if (argc < 2) { + pr_info("Probe point is not specified.\n"); + return -EINVAL; + } + if (isdigit(argv[1][0])) { + pr_info("probe point must be have a filename.\n"); + return -EINVAL; + } + arg = strchr(argv[1], ':'); + if (!arg) { + ret = -EINVAL; + goto fail_address_parse; + } + + *arg++ = '\0'; + filename = argv[1]; + ret = kern_path(filename, LOOKUP_FOLLOW, &path); + if (ret) + goto fail_address_parse; + + inode = igrab(path.dentry->d_inode); + path_put(&path); + + if (!inode || !S_ISREG(inode->i_mode)) { + ret = -EINVAL; + goto fail_address_parse; + } + + ret = kstrtoul(arg, 0, &offset); + if (ret) + goto fail_address_parse; + + argc -= 2; + argv += 2; + + /* setup a probe */ + if (!event) { + char *tail; + char *ptr; + + tail = kstrdup(kbasename(filename), GFP_KERNEL); + if (!tail) { + ret = -ENOMEM; + goto fail_address_parse; + } + + ptr = strpbrk(tail, ".-_"); + if (ptr) + *ptr = '\0'; + + snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_0x%lx", 'p', tail, offset); + event = buf; + kfree(tail); + } + + tu = alloc_trace_uprobe(group, event, argc, is_return); + if (IS_ERR(tu)) { + pr_info("Failed to allocate trace_uprobe.(%d)\n", (int)PTR_ERR(tu)); + ret = PTR_ERR(tu); + goto fail_address_parse; + } + tu->offset = offset; + tu->inode = inode; + tu->filename = kstrdup(filename, GFP_KERNEL); + + if (!tu->filename) { + pr_info("Failed to allocate filename.\n"); + ret = -ENOMEM; + goto error; + } + + /* parse arguments */ + ret = 0; + for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { + struct probe_arg *parg = &tu->tp.args[i]; + + /* Increment count for freeing args in error case */ + tu->tp.nr_args++; + + /* Parse argument name */ + arg = strchr(argv[i], '='); + if (arg) { + *arg++ = '\0'; + parg->name = kstrdup(argv[i], GFP_KERNEL); + } else { + arg = argv[i]; + /* If argument name is omitted, set "argN" */ + snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1); + parg->name = kstrdup(buf, GFP_KERNEL); + } + + if (!parg->name) { + pr_info("Failed to allocate argument[%d] name.\n", i); + ret = -ENOMEM; + goto error; + } + + if (!is_good_name(parg->name)) { + pr_info("Invalid argument[%d] name: %s\n", i, parg->name); + ret = -EINVAL; + goto error; + } + + if (traceprobe_conflict_field_name(parg->name, tu->tp.args, i)) { + pr_info("Argument[%d] name '%s' conflicts with " + "another field.\n", i, argv[i]); + ret = -EINVAL; + goto error; + } + + /* Parse fetch argument */ + ret = traceprobe_parse_probe_arg(arg, &tu->tp.size, parg, + is_return, false); + if (ret) { + pr_info("Parse error at argument[%d]. (%d)\n", i, ret); + goto error; + } + } + + ret = register_trace_uprobe(tu); + if (ret) + goto error; + return 0; + +error: + free_trace_uprobe(tu); + return ret; + +fail_address_parse: + if (inode) + iput(inode); + + pr_info("Failed to parse address or file.\n"); + + return ret; +} + +static int cleanup_all_probes(void) +{ + struct trace_uprobe *tu; + int ret = 0; + + mutex_lock(&uprobe_lock); + while (!list_empty(&uprobe_list)) { + tu = list_entry(uprobe_list.next, struct trace_uprobe, list); + ret = unregister_trace_uprobe(tu); + if (ret) + break; + } + mutex_unlock(&uprobe_lock); + return ret; +} + +/* Probes listing interfaces */ +static void *probes_seq_start(struct seq_file *m, loff_t *pos) +{ + mutex_lock(&uprobe_lock); + return seq_list_start(&uprobe_list, *pos); +} + +static void *probes_seq_next(struct seq_file *m, void *v, loff_t *pos) +{ + return seq_list_next(v, &uprobe_list, pos); +} + +static void probes_seq_stop(struct seq_file *m, void *v) +{ + mutex_unlock(&uprobe_lock); +} + +static int probes_seq_show(struct seq_file *m, void *v) +{ + struct trace_uprobe *tu = v; + char c = is_ret_probe(tu) ? 'r' : 'p'; + int i; + + seq_printf(m, "%c:%s/%s", c, tu->tp.call.class->system, + ftrace_event_name(&tu->tp.call)); + seq_printf(m, " %s:0x%p", tu->filename, (void *)tu->offset); + + for (i = 0; i < tu->tp.nr_args; i++) + seq_printf(m, " %s=%s", tu->tp.args[i].name, tu->tp.args[i].comm); + + seq_printf(m, "\n"); + return 0; +} + +static const struct seq_operations probes_seq_op = { + .start = probes_seq_start, + .next = probes_seq_next, + .stop = probes_seq_stop, + .show = probes_seq_show +}; + +static int probes_open(struct inode *inode, struct file *file) +{ + int ret; + + if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { + ret = cleanup_all_probes(); + if (ret) + return ret; + } + + return seq_open(file, &probes_seq_op); +} + +static ssize_t probes_write(struct file *file, const char __user *buffer, + size_t count, loff_t *ppos) +{ + return traceprobe_probes_write(file, buffer, count, ppos, create_trace_uprobe); +} + +static const struct file_operations uprobe_events_ops = { + .owner = THIS_MODULE, + .open = probes_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, + .write = probes_write, +}; + +/* Probes profiling interfaces */ +static int probes_profile_seq_show(struct seq_file *m, void *v) +{ + struct trace_uprobe *tu = v; + + seq_printf(m, " %s %-44s %15lu\n", tu->filename, + ftrace_event_name(&tu->tp.call), tu->nhit); + return 0; +} + +static const struct seq_operations profile_seq_op = { + .start = probes_seq_start, + .next = probes_seq_next, + .stop = probes_seq_stop, + .show = probes_profile_seq_show +}; + +static int profile_open(struct inode *inode, struct file *file) +{ + return seq_open(file, &profile_seq_op); +} + +static const struct file_operations uprobe_profile_ops = { + .owner = THIS_MODULE, + .open = profile_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +struct uprobe_cpu_buffer { + struct mutex mutex; + void *buf; +}; +static struct uprobe_cpu_buffer __percpu *uprobe_cpu_buffer; +static int uprobe_buffer_refcnt; + +static int uprobe_buffer_init(void) +{ + int cpu, err_cpu; + + uprobe_cpu_buffer = alloc_percpu(struct uprobe_cpu_buffer); + if (uprobe_cpu_buffer == NULL) + return -ENOMEM; + + for_each_possible_cpu(cpu) { + struct page *p = alloc_pages_node(cpu_to_node(cpu), + GFP_KERNEL, 0); + if (p == NULL) { + err_cpu = cpu; + goto err; + } + per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf = page_address(p); + mutex_init(&per_cpu_ptr(uprobe_cpu_buffer, cpu)->mutex); + } + + return 0; + +err: + for_each_possible_cpu(cpu) { + if (cpu == err_cpu) + break; + free_page((unsigned long)per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf); + } + + free_percpu(uprobe_cpu_buffer); + return -ENOMEM; +} + +static int uprobe_buffer_enable(void) +{ + int ret = 0; + + BUG_ON(!mutex_is_locked(&event_mutex)); + + if (uprobe_buffer_refcnt++ == 0) { + ret = uprobe_buffer_init(); + if (ret < 0) + uprobe_buffer_refcnt--; + } + + return ret; +} + +static void uprobe_buffer_disable(void) +{ + int cpu; + + BUG_ON(!mutex_is_locked(&event_mutex)); + + if (--uprobe_buffer_refcnt == 0) { + for_each_possible_cpu(cpu) + free_page((unsigned long)per_cpu_ptr(uprobe_cpu_buffer, + cpu)->buf); + + free_percpu(uprobe_cpu_buffer); + uprobe_cpu_buffer = NULL; + } +} + +static struct uprobe_cpu_buffer *uprobe_buffer_get(void) +{ + struct uprobe_cpu_buffer *ucb; + int cpu; + + cpu = raw_smp_processor_id(); + ucb = per_cpu_ptr(uprobe_cpu_buffer, cpu); + + /* + * Use per-cpu buffers for fastest access, but we might migrate + * so the mutex makes sure we have sole access to it. + */ + mutex_lock(&ucb->mutex); + + return ucb; +} + +static void uprobe_buffer_put(struct uprobe_cpu_buffer *ucb) +{ + mutex_unlock(&ucb->mutex); +} + +static void __uprobe_trace_func(struct trace_uprobe *tu, + unsigned long func, struct pt_regs *regs, + struct uprobe_cpu_buffer *ucb, int dsize, + struct ftrace_event_file *ftrace_file) +{ + struct uprobe_trace_entry_head *entry; + struct ring_buffer_event *event; + struct ring_buffer *buffer; + void *data; + int size, esize; + struct ftrace_event_call *call = &tu->tp.call; + + WARN_ON(call != ftrace_file->event_call); + + if (WARN_ON_ONCE(tu->tp.size + dsize > PAGE_SIZE)) + return; + + if (ftrace_trigger_soft_disabled(ftrace_file)) + return; + + esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); + size = esize + tu->tp.size + dsize; + event = trace_event_buffer_lock_reserve(&buffer, ftrace_file, + call->event.type, size, 0, 0); + if (!event) + return; + + entry = ring_buffer_event_data(event); + if (is_ret_probe(tu)) { + entry->vaddr[0] = func; + entry->vaddr[1] = instruction_pointer(regs); + data = DATAOF_TRACE_ENTRY(entry, true); + } else { + entry->vaddr[0] = instruction_pointer(regs); + data = DATAOF_TRACE_ENTRY(entry, false); + } + + memcpy(data, ucb->buf, tu->tp.size + dsize); + + event_trigger_unlock_commit(ftrace_file, buffer, event, entry, 0, 0); +} + +/* uprobe handler */ +static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs, + struct uprobe_cpu_buffer *ucb, int dsize) +{ + struct event_file_link *link; + + if (is_ret_probe(tu)) + return 0; + + rcu_read_lock(); + list_for_each_entry_rcu(link, &tu->tp.files, list) + __uprobe_trace_func(tu, 0, regs, ucb, dsize, link->file); + rcu_read_unlock(); + + return 0; +} + +static void uretprobe_trace_func(struct trace_uprobe *tu, unsigned long func, + struct pt_regs *regs, + struct uprobe_cpu_buffer *ucb, int dsize) +{ + struct event_file_link *link; + + rcu_read_lock(); + list_for_each_entry_rcu(link, &tu->tp.files, list) + __uprobe_trace_func(tu, func, regs, ucb, dsize, link->file); + rcu_read_unlock(); +} + +/* Event entry printers */ +static enum print_line_t +print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *event) +{ + struct uprobe_trace_entry_head *entry; + struct trace_seq *s = &iter->seq; + struct trace_uprobe *tu; + u8 *data; + int i; + + entry = (struct uprobe_trace_entry_head *)iter->ent; + tu = container_of(event, struct trace_uprobe, tp.call.event); + + if (is_ret_probe(tu)) { + if (!trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)", + ftrace_event_name(&tu->tp.call), + entry->vaddr[1], entry->vaddr[0])) + goto partial; + data = DATAOF_TRACE_ENTRY(entry, true); + } else { + if (!trace_seq_printf(s, "%s: (0x%lx)", + ftrace_event_name(&tu->tp.call), + entry->vaddr[0])) + goto partial; + data = DATAOF_TRACE_ENTRY(entry, false); + } + + for (i = 0; i < tu->tp.nr_args; i++) { + struct probe_arg *parg = &tu->tp.args[i]; + + if (!parg->type->print(s, parg->name, data + parg->offset, entry)) + goto partial; + } + + if (trace_seq_puts(s, "\n")) + return TRACE_TYPE_HANDLED; + +partial: + return TRACE_TYPE_PARTIAL_LINE; +} + +typedef bool (*filter_func_t)(struct uprobe_consumer *self, + enum uprobe_filter_ctx ctx, + struct mm_struct *mm); + +static int +probe_event_enable(struct trace_uprobe *tu, struct ftrace_event_file *file, + filter_func_t filter) +{ + bool enabled = trace_probe_is_enabled(&tu->tp); + struct event_file_link *link = NULL; + int ret; + + if (file) { + if (tu->tp.flags & TP_FLAG_PROFILE) + return -EINTR; + + link = kmalloc(sizeof(*link), GFP_KERNEL); + if (!link) + return -ENOMEM; + + link->file = file; + list_add_tail_rcu(&link->list, &tu->tp.files); + + tu->tp.flags |= TP_FLAG_TRACE; + } else { + if (tu->tp.flags & TP_FLAG_TRACE) + return -EINTR; + + tu->tp.flags |= TP_FLAG_PROFILE; + } + + WARN_ON(!uprobe_filter_is_empty(&tu->filter)); + + if (enabled) + return 0; + + ret = uprobe_buffer_enable(); + if (ret) + goto err_flags; + + tu->consumer.filter = filter; + ret = uprobe_register(tu->inode, tu->offset, &tu->consumer); + if (ret) + goto err_buffer; + + return 0; + + err_buffer: + uprobe_buffer_disable(); + + err_flags: + if (file) { + list_del(&link->list); + kfree(link); + tu->tp.flags &= ~TP_FLAG_TRACE; + } else { + tu->tp.flags &= ~TP_FLAG_PROFILE; + } + return ret; +} + +static void +probe_event_disable(struct trace_uprobe *tu, struct ftrace_event_file *file) +{ + if (!trace_probe_is_enabled(&tu->tp)) + return; + + if (file) { + struct event_file_link *link; + + link = find_event_file_link(&tu->tp, file); + if (!link) + return; + + list_del_rcu(&link->list); + /* synchronize with u{,ret}probe_trace_func */ + synchronize_sched(); + kfree(link); + + if (!list_empty(&tu->tp.files)) + return; + } + + WARN_ON(!uprobe_filter_is_empty(&tu->filter)); + + uprobe_unregister(tu->inode, tu->offset, &tu->consumer); + tu->tp.flags &= file ? ~TP_FLAG_TRACE : ~TP_FLAG_PROFILE; + + uprobe_buffer_disable(); +} + +static int uprobe_event_define_fields(struct ftrace_event_call *event_call) +{ + int ret, i, size; + struct uprobe_trace_entry_head field; + struct trace_uprobe *tu = event_call->data; + + if (is_ret_probe(tu)) { + DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_FUNC, 0); + DEFINE_FIELD(unsigned long, vaddr[1], FIELD_STRING_RETIP, 0); + size = SIZEOF_TRACE_ENTRY(true); + } else { + DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_IP, 0); + size = SIZEOF_TRACE_ENTRY(false); + } + /* Set argument names as fields */ + for (i = 0; i < tu->tp.nr_args; i++) { + struct probe_arg *parg = &tu->tp.args[i]; + + ret = trace_define_field(event_call, parg->type->fmttype, + parg->name, size + parg->offset, + parg->type->size, parg->type->is_signed, + FILTER_OTHER); + + if (ret) + return ret; + } + return 0; +} + +#ifdef CONFIG_PERF_EVENTS +static bool +__uprobe_perf_filter(struct trace_uprobe_filter *filter, struct mm_struct *mm) +{ + struct perf_event *event; + + if (filter->nr_systemwide) + return true; + + list_for_each_entry(event, &filter->perf_events, hw.tp_list) { + if (event->hw.tp_target->mm == mm) + return true; + } + + return false; +} + +static inline bool +uprobe_filter_event(struct trace_uprobe *tu, struct perf_event *event) +{ + return __uprobe_perf_filter(&tu->filter, event->hw.tp_target->mm); +} + +static int uprobe_perf_close(struct trace_uprobe *tu, struct perf_event *event) +{ + bool done; + + write_lock(&tu->filter.rwlock); + if (event->hw.tp_target) { + list_del(&event->hw.tp_list); + done = tu->filter.nr_systemwide || + (event->hw.tp_target->flags & PF_EXITING) || + uprobe_filter_event(tu, event); + } else { + tu->filter.nr_systemwide--; + done = tu->filter.nr_systemwide; + } + write_unlock(&tu->filter.rwlock); + + if (!done) + return uprobe_apply(tu->inode, tu->offset, &tu->consumer, false); + + return 0; +} + +static int uprobe_perf_open(struct trace_uprobe *tu, struct perf_event *event) +{ + bool done; + int err; + + write_lock(&tu->filter.rwlock); + if (event->hw.tp_target) { + /* + * event->parent != NULL means copy_process(), we can avoid + * uprobe_apply(). current->mm must be probed and we can rely + * on dup_mmap() which preserves the already installed bp's. + * + * attr.enable_on_exec means that exec/mmap will install the + * breakpoints we need. + */ + done = tu->filter.nr_systemwide || + event->parent || event->attr.enable_on_exec || + uprobe_filter_event(tu, event); + list_add(&event->hw.tp_list, &tu->filter.perf_events); + } else { + done = tu->filter.nr_systemwide; + tu->filter.nr_systemwide++; + } + write_unlock(&tu->filter.rwlock); + + err = 0; + if (!done) { + err = uprobe_apply(tu->inode, tu->offset, &tu->consumer, true); + if (err) + uprobe_perf_close(tu, event); + } + return err; +} + +static bool uprobe_perf_filter(struct uprobe_consumer *uc, + enum uprobe_filter_ctx ctx, struct mm_struct *mm) +{ + struct trace_uprobe *tu; + int ret; + + tu = container_of(uc, struct trace_uprobe, consumer); + read_lock(&tu->filter.rwlock); + ret = __uprobe_perf_filter(&tu->filter, mm); + read_unlock(&tu->filter.rwlock); + + return ret; +} + +static void __uprobe_perf_func(struct trace_uprobe *tu, + unsigned long func, struct pt_regs *regs, + struct uprobe_cpu_buffer *ucb, int dsize) +{ + struct ftrace_event_call *call = &tu->tp.call; + struct uprobe_trace_entry_head *entry; + struct hlist_head *head; + void *data; + int size, esize; + int rctx; + + esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); + + size = esize + tu->tp.size + dsize; + size = ALIGN(size + sizeof(u32), sizeof(u64)) - sizeof(u32); + if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, "profile buffer not large enough")) + return; + + preempt_disable(); + head = this_cpu_ptr(call->perf_events); + if (hlist_empty(head)) + goto out; + + entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx); + if (!entry) + goto out; + + if (is_ret_probe(tu)) { + entry->vaddr[0] = func; + entry->vaddr[1] = instruction_pointer(regs); + data = DATAOF_TRACE_ENTRY(entry, true); + } else { + entry->vaddr[0] = instruction_pointer(regs); + data = DATAOF_TRACE_ENTRY(entry, false); + } + + memcpy(data, ucb->buf, tu->tp.size + dsize); + + if (size - esize > tu->tp.size + dsize) { + int len = tu->tp.size + dsize; + + memset(data + len, 0, size - esize - len); + } + + perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL); + out: + preempt_enable(); +} + +/* uprobe profile handler */ +static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs, + struct uprobe_cpu_buffer *ucb, int dsize) +{ + if (!uprobe_perf_filter(&tu->consumer, 0, current->mm)) + return UPROBE_HANDLER_REMOVE; + + if (!is_ret_probe(tu)) + __uprobe_perf_func(tu, 0, regs, ucb, dsize); + return 0; +} + +static void uretprobe_perf_func(struct trace_uprobe *tu, unsigned long func, + struct pt_regs *regs, + struct uprobe_cpu_buffer *ucb, int dsize) +{ + __uprobe_perf_func(tu, func, regs, ucb, dsize); +} +#endif /* CONFIG_PERF_EVENTS */ + +static int +trace_uprobe_register(struct ftrace_event_call *event, enum trace_reg type, + void *data) +{ + struct trace_uprobe *tu = event->data; + struct ftrace_event_file *file = data; + + switch (type) { + case TRACE_REG_REGISTER: + return probe_event_enable(tu, file, NULL); + + case TRACE_REG_UNREGISTER: + probe_event_disable(tu, file); + return 0; + +#ifdef CONFIG_PERF_EVENTS + case TRACE_REG_PERF_REGISTER: + return probe_event_enable(tu, NULL, uprobe_perf_filter); + + case TRACE_REG_PERF_UNREGISTER: + probe_event_disable(tu, NULL); + return 0; + + case TRACE_REG_PERF_OPEN: + return uprobe_perf_open(tu, data); + + case TRACE_REG_PERF_CLOSE: + return uprobe_perf_close(tu, data); + +#endif + default: + return 0; + } + return 0; +} + +static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs) +{ + struct trace_uprobe *tu; + struct uprobe_dispatch_data udd; + struct uprobe_cpu_buffer *ucb; + int dsize, esize; + int ret = 0; + + + tu = container_of(con, struct trace_uprobe, consumer); + tu->nhit++; + + udd.tu = tu; + udd.bp_addr = instruction_pointer(regs); + + current->utask->vaddr = (unsigned long) &udd; + + if (WARN_ON_ONCE(!uprobe_cpu_buffer)) + return 0; + + dsize = __get_data_size(&tu->tp, regs); + esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); + + ucb = uprobe_buffer_get(); + store_trace_args(esize, &tu->tp, regs, ucb->buf, dsize); + + if (tu->tp.flags & TP_FLAG_TRACE) + ret |= uprobe_trace_func(tu, regs, ucb, dsize); + +#ifdef CONFIG_PERF_EVENTS + if (tu->tp.flags & TP_FLAG_PROFILE) + ret |= uprobe_perf_func(tu, regs, ucb, dsize); +#endif + uprobe_buffer_put(ucb); + return ret; +} + +static int uretprobe_dispatcher(struct uprobe_consumer *con, + unsigned long func, struct pt_regs *regs) +{ + struct trace_uprobe *tu; + struct uprobe_dispatch_data udd; + struct uprobe_cpu_buffer *ucb; + int dsize, esize; + + tu = container_of(con, struct trace_uprobe, consumer); + + udd.tu = tu; + udd.bp_addr = func; + + current->utask->vaddr = (unsigned long) &udd; + + if (WARN_ON_ONCE(!uprobe_cpu_buffer)) + return 0; + + dsize = __get_data_size(&tu->tp, regs); + esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); + + ucb = uprobe_buffer_get(); + store_trace_args(esize, &tu->tp, regs, ucb->buf, dsize); + + if (tu->tp.flags & TP_FLAG_TRACE) + uretprobe_trace_func(tu, func, regs, ucb, dsize); + +#ifdef CONFIG_PERF_EVENTS + if (tu->tp.flags & TP_FLAG_PROFILE) + uretprobe_perf_func(tu, func, regs, ucb, dsize); +#endif + uprobe_buffer_put(ucb); + return 0; +} + +static struct trace_event_functions uprobe_funcs = { + .trace = print_uprobe_event +}; + +static int register_uprobe_event(struct trace_uprobe *tu) +{ + struct ftrace_event_call *call = &tu->tp.call; + int ret; + + /* Initialize ftrace_event_call */ + INIT_LIST_HEAD(&call->class->fields); + call->event.funcs = &uprobe_funcs; + call->class->define_fields = uprobe_event_define_fields; + + if (set_print_fmt(&tu->tp, is_ret_probe(tu)) < 0) + return -ENOMEM; + + ret = register_ftrace_event(&call->event); + if (!ret) { + kfree(call->print_fmt); + return -ENODEV; + } + call->flags = 0; + call->class->reg = trace_uprobe_register; + call->data = tu; + ret = trace_add_event_call(call); + + if (ret) { + pr_info("Failed to register uprobe event: %s\n", + ftrace_event_name(call)); + kfree(call->print_fmt); + unregister_ftrace_event(&call->event); + } + + return ret; +} + +static int unregister_uprobe_event(struct trace_uprobe *tu) +{ + int ret; + + /* tu->event is unregistered in trace_remove_event_call() */ + ret = trace_remove_event_call(&tu->tp.call); + if (ret) + return ret; + kfree(tu->tp.call.print_fmt); + tu->tp.call.print_fmt = NULL; + return 0; +} + +/* Make a trace interface for controling probe points */ +static __init int init_uprobe_trace(void) +{ + struct dentry *d_tracer; + + d_tracer = tracing_init_dentry(); + if (!d_tracer) + return 0; + + trace_create_file("uprobe_events", 0644, d_tracer, + NULL, &uprobe_events_ops); + /* Profile interface */ + trace_create_file("uprobe_profile", 0444, d_tracer, + NULL, &uprobe_profile_ops); + return 0; +} + +fs_initcall(init_uprobe_trace); diff --git a/kernel/trace/trace_workqueue.c b/kernel/trace/trace_workqueue.c deleted file mode 100644 index 97fcea4acce..00000000000 --- a/kernel/trace/trace_workqueue.c +++ /dev/null @@ -1,275 +0,0 @@ -/* - * Workqueue statistical tracer. - * - * Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com> - * - */ - - -#include <trace/events/workqueue.h> -#include <linux/list.h> -#include <linux/percpu.h> -#include "trace_stat.h" -#include "trace.h" - - -/* A cpu workqueue thread */ -struct cpu_workqueue_stats { - struct list_head list; - int cpu; - pid_t pid; -/* Can be inserted from interrupt or user context, need to be atomic */ - atomic_t inserted; -/* - * Don't need to be atomic, works are serialized in a single workqueue thread - * on a single CPU. - */ - unsigned int executed; -}; - -/* List of workqueue threads on one cpu */ -struct workqueue_global_stats { - struct list_head list; - spinlock_t lock; -}; - -/* Don't need a global lock because allocated before the workqueues, and - * never freed. - */ -static DEFINE_PER_CPU(struct workqueue_global_stats, all_workqueue_stat); -#define workqueue_cpu_stat(cpu) (&per_cpu(all_workqueue_stat, cpu)) - -/* Insertion of a work */ -static void -probe_workqueue_insertion(struct task_struct *wq_thread, - struct work_struct *work) -{ - int cpu = cpumask_first(&wq_thread->cpus_allowed); - struct cpu_workqueue_stats *node; - unsigned long flags; - - spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags); - list_for_each_entry(node, &workqueue_cpu_stat(cpu)->list, list) { - if (node->pid == wq_thread->pid) { - atomic_inc(&node->inserted); - goto found; - } - } - pr_debug("trace_workqueue: entry not found\n"); -found: - spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags); -} - -/* Execution of a work */ -static void -probe_workqueue_execution(struct task_struct *wq_thread, - struct work_struct *work) -{ - int cpu = cpumask_first(&wq_thread->cpus_allowed); - struct cpu_workqueue_stats *node; - unsigned long flags; - - spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags); - list_for_each_entry(node, &workqueue_cpu_stat(cpu)->list, list) { - if (node->pid == wq_thread->pid) { - node->executed++; - goto found; - } - } - pr_debug("trace_workqueue: entry not found\n"); -found: - spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags); -} - -/* Creation of a cpu workqueue thread */ -static void probe_workqueue_creation(struct task_struct *wq_thread, int cpu) -{ - struct cpu_workqueue_stats *cws; - unsigned long flags; - - WARN_ON(cpu < 0); - - /* Workqueues are sometimes created in atomic context */ - cws = kzalloc(sizeof(struct cpu_workqueue_stats), GFP_ATOMIC); - if (!cws) { - pr_warning("trace_workqueue: not enough memory\n"); - return; - } - INIT_LIST_HEAD(&cws->list); - cws->cpu = cpu; - - cws->pid = wq_thread->pid; - - spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags); - list_add_tail(&cws->list, &workqueue_cpu_stat(cpu)->list); - spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags); -} - -/* Destruction of a cpu workqueue thread */ -static void probe_workqueue_destruction(struct task_struct *wq_thread) -{ - /* Workqueue only execute on one cpu */ - int cpu = cpumask_first(&wq_thread->cpus_allowed); - struct cpu_workqueue_stats *node, *next; - unsigned long flags; - - spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags); - list_for_each_entry_safe(node, next, &workqueue_cpu_stat(cpu)->list, - list) { - if (node->pid == wq_thread->pid) { - list_del(&node->list); - kfree(node); - goto found; - } - } - - pr_debug("trace_workqueue: don't find workqueue to destroy\n"); -found: - spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags); - -} - -static struct cpu_workqueue_stats *workqueue_stat_start_cpu(int cpu) -{ - unsigned long flags; - struct cpu_workqueue_stats *ret = NULL; - - - spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags); - - if (!list_empty(&workqueue_cpu_stat(cpu)->list)) - ret = list_entry(workqueue_cpu_stat(cpu)->list.next, - struct cpu_workqueue_stats, list); - - spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags); - - return ret; -} - -static void *workqueue_stat_start(struct tracer_stat *trace) -{ - int cpu; - void *ret = NULL; - - for_each_possible_cpu(cpu) { - ret = workqueue_stat_start_cpu(cpu); - if (ret) - return ret; - } - return NULL; -} - -static void *workqueue_stat_next(void *prev, int idx) -{ - struct cpu_workqueue_stats *prev_cws = prev; - int cpu = prev_cws->cpu; - unsigned long flags; - void *ret = NULL; - - spin_lock_irqsave(&workqueue_cpu_stat(cpu)->lock, flags); - if (list_is_last(&prev_cws->list, &workqueue_cpu_stat(cpu)->list)) { - spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags); - do { - cpu = cpumask_next(cpu, cpu_possible_mask); - if (cpu >= nr_cpu_ids) - return NULL; - } while (!(ret = workqueue_stat_start_cpu(cpu))); - return ret; - } - spin_unlock_irqrestore(&workqueue_cpu_stat(cpu)->lock, flags); - - return list_entry(prev_cws->list.next, struct cpu_workqueue_stats, - list); -} - -static int workqueue_stat_show(struct seq_file *s, void *p) -{ - struct cpu_workqueue_stats *cws = p; - struct pid *pid; - struct task_struct *tsk; - - pid = find_get_pid(cws->pid); - if (pid) { - tsk = get_pid_task(pid, PIDTYPE_PID); - if (tsk) { - seq_printf(s, "%3d %6d %6u %s\n", cws->cpu, - atomic_read(&cws->inserted), cws->executed, - tsk->comm); - put_task_struct(tsk); - } - put_pid(pid); - } - - return 0; -} - -static int workqueue_stat_headers(struct seq_file *s) -{ - seq_printf(s, "# CPU INSERTED EXECUTED NAME\n"); - seq_printf(s, "# | | | |\n"); - return 0; -} - -struct tracer_stat workqueue_stats __read_mostly = { - .name = "workqueues", - .stat_start = workqueue_stat_start, - .stat_next = workqueue_stat_next, - .stat_show = workqueue_stat_show, - .stat_headers = workqueue_stat_headers -}; - - -int __init stat_workqueue_init(void) -{ - if (register_stat_tracer(&workqueue_stats)) { - pr_warning("Unable to register workqueue stat tracer\n"); - return 1; - } - - return 0; -} -fs_initcall(stat_workqueue_init); - -/* - * Workqueues are created very early, just after pre-smp initcalls. - * So we must register our tracepoints at this stage. - */ -int __init trace_workqueue_early_init(void) -{ - int ret, cpu; - - ret = register_trace_workqueue_insertion(probe_workqueue_insertion); - if (ret) - goto out; - - ret = register_trace_workqueue_execution(probe_workqueue_execution); - if (ret) - goto no_insertion; - - ret = register_trace_workqueue_creation(probe_workqueue_creation); - if (ret) - goto no_execution; - - ret = register_trace_workqueue_destruction(probe_workqueue_destruction); - if (ret) - goto no_creation; - - for_each_possible_cpu(cpu) { - spin_lock_init(&workqueue_cpu_stat(cpu)->lock); - INIT_LIST_HEAD(&workqueue_cpu_stat(cpu)->list); - } - - return 0; - -no_creation: - unregister_trace_workqueue_creation(probe_workqueue_creation); -no_execution: - unregister_trace_workqueue_execution(probe_workqueue_execution); -no_insertion: - unregister_trace_workqueue_insertion(probe_workqueue_insertion); -out: - pr_warning("trace_workqueue: unable to trace workqueues\n"); - - return 1; -} -early_initcall(trace_workqueue_early_init); |