linux/kernel/trace/trace_syscalls.c, branch v3.0.86

tracing/syscalls: Early terminate search for sys_ni_syscall

2011-02-08T02:30:14Z

Many system calls are unimplemented and mapped to sys_ni_syscall, but at boot ftrace would still search through every syscall metadata entry for a match which wouldn't be there. This patch adds causes the search to terminate early if the system call is not mapped. Signed-off-by: Ian Munsie LKML-Reference: <1296703645-18718-7-git-send-email-imunsie@au1.ibm.com> Signed-off-by: Steven Rostedt

tracing/syscalls: Allow arch specific syscall symbol matching

2011-02-08T02:29:03Z

Some architectures have unusual symbol names and the generic code to match the symbol name with the function name for the syscall metadata will fail. For example, symbols on PPC64 start with a period and the generic code will fail to match them. This patch moves the match logic out into a separate function which an arch can override by defining ARCH_HAS_SYSCALL_MATCH_SYM_NAME in asm/ftrace.h and implementing arch_syscall_match_sym_name. Signed-off-by: Ian Munsie LKML-Reference: <1296703645-18718-5-git-send-email-imunsie@au1.ibm.com> Signed-off-by: Steven Rostedt

tracing/syscalls: Make arch_syscall_addr weak

2011-02-08T02:26:22Z

Some architectures use non-trivial system call tables and will not work with the generic arch_syscall_addr code. For example, PowerPC64 uses a table of twin long longs. This patch makes the generic arch_syscall_addr weak to allow architectures with non-trivial system call tables to override it. Signed-off-by: Ian Munsie LKML-Reference: <1296703645-18718-4-git-send-email-imunsie@au1.ibm.com> Signed-off-by: Steven Rostedt

tracing/syscalls: Convert redundant syscall_nr checks into WARN_ON

2011-02-08T02:25:52Z

With the ftrace events now checking if the syscall_nr is valid upon initialisation it should no longer be possible to register or unregister a syscall event without a valid syscall_nr since they should not be created. This adds a WARN_ON_ONCE in the register and unregister functions to locate potential regressions in the future. Signed-off-by: Ian Munsie LKML-Reference: <1296703645-18718-3-git-send-email-imunsie@au1.ibm.com> Signed-off-by: Steven Rostedt

tracing/syscalls: Don't add events for unmapped syscalls

2011-02-08T02:24:44Z

FTRACE_SYSCALLS would create events for each and every system call, even if it had failed to map the system call's name with it's number. This resulted in a number of events being created that would not behave as expected. This could happen, for example, on architectures who's symbol names are unusual and will not match the system call name. It could also happen with system calls which were mapped to sys_ni_syscall. This patch changes the default system call number in the metadata to -1. If the system call name from the metadata is not successfully mapped to a system call number during boot, than the event initialisation routine will now return an error, preventing the event from being created. Signed-off-by: Ian Munsie LKML-Reference: <1296703645-18718-2-git-send-email-imunsie@au1.ibm.com> Signed-off-by: Steven Rostedt

tracing: Replace syscall_meta_data struct array with pointer array

2011-02-03T14:29:06Z

Currently the syscall_meta structures for the syscall tracepoints are placed in the __syscall_metadata section, and at link time, the linker makes one large array of all these syscall metadata structures. On boot up, this array is read (much like the initcall sections) and the syscall data is processed. The problem is that there is no guarantee that gcc will place complex structures nicely together in an array format. Two structures in the same file may be placed awkwardly, because gcc has no clue that they are suppose to be in an array. A hack was used previous to force the alignment to 4, to pack the structures together. But this caused alignment issues with other architectures (sparc). Instead of packing the structures into an array, the structures' addresses are now put into the __syscall_metadata section. As pointers are always the natural alignment, gcc should always pack them tightly together (otherwise initcall, extable, etc would also fail). By having the pointers to the structures in the section, we can still iterate the trace_events without causing unnecessary alignment problems with other architectures, or depending on the current behaviour of gcc that will likely change in the future just to tick us kernel developers off a little more. The __syscall_metadata section is also moved into the .init.data section as it is now only needed at boot up. Suggested-by: David Miller Acked-by: David S. Miller Cc: Mathieu Desnoyers Signed-off-by: Steven Rostedt

tracing: Remove syscall_exit_fields

2011-01-14T23:06:35Z

There is no need for syscall_exit_fields as the syscall exit event class can already host the fields in its structure, like most other trace events do by default. Use that default behavior instead. Following this scheme, we don't need anymore to override the get_fields() callback of the syscall exit event class either. Hence both syscall_exit_fields and syscall_get_exit_fields() can be removed. Also changed some indentation to keep the following under 80 characters: ".fields = LIST_HEAD_INIT(event_class_syscall_exit.fields)," Acked-by: Frederic Weisbecker Signed-off-by: Lai Jiangshan LKML-Reference: <4D301C0E.8090408@cn.fujitsu.com> Signed-off-by: Steven Rostedt

tracing: Use a global field list for all syscall exit events

2010-06-28T21:12:44Z

All syscall exit events have the same fields. The kernel size drops 2.5K: text data bss dec hex filename 7018612 2034376 7251132 16304120 f8c7f8 vmlinux.o.orig 7018612 2031888 7251132 16301632 f8be40 vmlinux.o Signed-off-by: Li Zefan LKML-Reference: <4BFA3746.8070100@cn.fujitsu.com> Signed-off-by: Steven Rostedt

perf_events, trace: Fix probe unregister race

2010-05-31T06:46:09Z

tracepoint_probe_unregister() does not synchronize against the probe callbacks, so do that explicitly. This properly serializes the callbacks and the free of the data used therein. Also, use this_cpu_ptr() where possible. Acked-by: Frederic Weisbecker Signed-off-by: Peter Zijlstra LKML-Reference: <1274438476.1674.1702.camel@laptop> Signed-off-by: Ingo Molnar

Merge branch 'perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip into trace/tip/tracing/core-7

2010-05-21T15:49:57Z

Conflicts: include/linux/ftrace_event.h include/trace/ftrace.h kernel/trace/trace_event_perf.c kernel/trace/trace_kprobe.c kernel/trace/trace_syscalls.c Signed-off-by: Steven Rostedt