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-rw-r--r--kernel/trace/ftrace.c38
-rw-r--r--kernel/trace/ring_buffer.c26
-rw-r--r--kernel/trace/trace.c368
-rw-r--r--kernel/trace/trace.h27
-rw-r--r--kernel/trace/trace_event_perf.c10
-rw-r--r--kernel/trace/trace_events.c264
-rw-r--r--kernel/trace/trace_events_filter.c10
-rw-r--r--kernel/trace/trace_functions.c105
-rw-r--r--kernel/trace/trace_functions_graph.c54
-rw-r--r--kernel/trace/trace_irqsoff.c4
-rw-r--r--kernel/trace/trace_kprobe.c209
-rw-r--r--kernel/trace/trace_mmiotrace.c8
-rw-r--r--kernel/trace/trace_output.c14
-rw-r--r--kernel/trace/trace_selftest.c18
-rw-r--r--kernel/trace/trace_syscalls.c47
-rw-r--r--kernel/trace/trace_uprobe.c6
16 files changed, 799 insertions, 409 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 6c508ff33c6..67708f46baa 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -413,6 +413,17 @@ static int __register_ftrace_function(struct ftrace_ops *ops)
return 0;
}
+static void ftrace_sync(struct work_struct *work)
+{
+ /*
+ * 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.
+ */
+}
+
static int __unregister_ftrace_function(struct ftrace_ops *ops)
{
int ret;
@@ -440,8 +451,12 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
* so there'll be no new users. We must ensure
* all current users are done before we free
* the control data.
+ * Note synchronize_sched() is not enough, as we
+ * use preempt_disable() to do RCU, but the function
+ * tracer can be called where RCU is not active
+ * (before user_exit()).
*/
- synchronize_sched();
+ schedule_on_each_cpu(ftrace_sync);
control_ops_free(ops);
}
} else
@@ -456,9 +471,13 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
/*
* Dynamic ops may be freed, we must make sure that all
* callers are done before leaving this function.
+ *
+ * Again, normal synchronize_sched() is not good enough.
+ * We need to do a hard force of sched synchronization.
*/
if (ops->flags & FTRACE_OPS_FL_DYNAMIC)
- synchronize_sched();
+ schedule_on_each_cpu(ftrace_sync);
+
return 0;
}
@@ -622,12 +641,18 @@ static int function_stat_show(struct seq_file *m, void *v)
if (rec->counter <= 1)
stddev = 0;
else {
- stddev = rec->time_squared - rec->counter * avg * avg;
+ /*
+ * 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 - 1) * 1000);
+ do_div(stddev, rec->counter * (rec->counter - 1) * 1000);
}
trace_seq_init(&s);
@@ -3512,8 +3537,12 @@ EXPORT_SYMBOL_GPL(ftrace_set_global_notrace);
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)
{
+ ftrace_filter_param = true;
strlcpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE);
return 1;
}
@@ -3521,6 +3550,7 @@ __setup("ftrace_notrace=", set_ftrace_notrace);
static int __init set_ftrace_filter(char *str)
{
+ ftrace_filter_param = true;
strlcpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE);
return 1;
}
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index e444ff88f0a..cc2f66f68dc 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -36,11 +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",
@@ -1066,7 +1066,7 @@ static int rb_check_list(struct ring_buffer_per_cpu *cpu_buffer,
}
/**
- * check_pages - integrity check of buffer pages
+ * 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
@@ -1258,7 +1258,7 @@ 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.
*
@@ -1607,6 +1607,7 @@ static void update_pages_handler(struct work_struct *work)
* ring_buffer_resize - resize the ring buffer
* @buffer: the buffer to resize.
* @size: the new size.
+ * @cpu_id: the cpu buffer to resize
*
* Minimum size is 2 * BUF_PAGE_SIZE.
*
@@ -3956,11 +3957,11 @@ EXPORT_SYMBOL_GPL(ring_buffer_consume);
* expected.
*
* After a sequence of ring_buffer_read_prepare calls, the user is
- * expected to make at least one call to ring_buffer_prepare_sync.
+ * 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_finish.
+ * This overall must be paired with ring_buffer_read_finish.
*/
struct ring_buffer_iter *
ring_buffer_read_prepare(struct ring_buffer *buffer, int cpu)
@@ -4009,7 +4010,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_read_prepare_sync);
* an intervening ring_buffer_read_prepare_sync must have been
* performed.
*
- * Must be paired with ring_buffer_finish.
+ * Must be paired with ring_buffer_read_finish.
*/
void
ring_buffer_read_start(struct ring_buffer_iter *iter)
@@ -4031,7 +4032,7 @@ ring_buffer_read_start(struct ring_buffer_iter *iter)
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
@@ -4346,6 +4347,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_swap_cpu);
/**
* 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
@@ -4403,7 +4405,7 @@ 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);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index e71a8be4a6e..3f2477713ac 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -115,6 +115,9 @@ cpumask_var_t __read_mostly tracing_buffer_mask;
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(const char *buf);
#define MAX_TRACER_SIZE 100
@@ -149,6 +152,13 @@ static int __init set_ftrace_dump_on_oops(char *str)
}
__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;
@@ -170,6 +180,7 @@ static int __init set_trace_boot_options(char *str)
}
__setup("trace_options=", set_trace_boot_options);
+
unsigned long long ns2usecs(cycle_t nsec)
{
nsec += 500;
@@ -193,6 +204,37 @@ static struct trace_array global_trace;
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;
+}
+
+static void __trace_array_put(struct trace_array *this_tr)
+{
+ WARN_ON(!this_tr->ref);
+ this_tr->ref--;
+}
+
+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_current_check_discard(struct ring_buffer *buffer,
struct ftrace_event_call *call, void *rec,
struct ring_buffer_event *event)
@@ -215,9 +257,24 @@ cycle_t ftrace_now(int cpu)
return ts;
}
+/**
+ * tracing_is_enabled - Show if global_trace has been disabled
+ *
+ * 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 tracing_is_on();
+ /*
+ * 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;
}
/*
@@ -240,7 +297,7 @@ static struct tracer *trace_types __read_mostly;
/*
* trace_types_lock is used to protect the trace_types list.
*/
-static DEFINE_MUTEX(trace_types_lock);
+DEFINE_MUTEX(trace_types_lock);
/*
* serialize the access of the ring buffer
@@ -330,6 +387,23 @@ unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
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();
+}
+
/**
* tracing_on - enable tracing buffers
*
@@ -338,15 +412,7 @@ unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
*/
void tracing_on(void)
{
- if (global_trace.trace_buffer.buffer)
- ring_buffer_record_on(global_trace.trace_buffer.buffer);
- /*
- * This flag is only looked at when buffers haven't been
- * allocated yet. We don't really care about the race
- * between setting this flag and actually turning
- * on the buffer.
- */
- global_trace.buffer_disabled = 0;
+ tracer_tracing_on(&global_trace);
}
EXPORT_SYMBOL_GPL(tracing_on);
@@ -540,6 +606,23 @@ void tracing_snapshot_alloc(void)
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);
+ /*
+ * 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 = 1;
+ /* Make the flag seen by readers */
+ smp_wmb();
+}
+
/**
* tracing_off - turn off tracing buffers
*
@@ -550,26 +633,35 @@ EXPORT_SYMBOL_GPL(tracing_snapshot_alloc);
*/
void tracing_off(void)
{
- if (global_trace.trace_buffer.buffer)
- ring_buffer_record_off(global_trace.trace_buffer.buffer);
- /*
- * This flag is only looked at when buffers haven't been
- * allocated yet. We don't really care about the race
- * between setting this flag and actually turning
- * on the buffer.
- */
- global_trace.buffer_disabled = 1;
+ 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)
{
- if (global_trace.trace_buffer.buffer)
- return ring_buffer_record_is_on(global_trace.trace_buffer.buffer);
- return !global_trace.buffer_disabled;
+ return tracer_tracing_is_on(&global_trace);
}
EXPORT_SYMBOL_GPL(tracing_is_on);
@@ -1543,15 +1635,6 @@ trace_function(struct trace_array *tr,
__buffer_unlock_commit(buffer, event);
}
-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);
-}
-
#ifdef CONFIG_STACKTRACE
#define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long))
@@ -2768,10 +2851,9 @@ static const struct seq_operations tracer_seq_ops = {
};
static struct trace_iterator *
-__tracing_open(struct inode *inode, struct file *file, bool snapshot)
+__tracing_open(struct trace_array *tr, struct trace_cpu *tc,
+ struct inode *inode, struct file *file, bool snapshot)
{
- struct trace_cpu *tc = inode->i_private;
- struct trace_array *tr = tc->tr;
struct trace_iterator *iter;
int cpu;
@@ -2850,8 +2932,6 @@ __tracing_open(struct inode *inode, struct file *file, bool snapshot)
tracing_iter_reset(iter, cpu);
}
- tr->ref++;
-
mutex_unlock(&trace_types_lock);
return iter;
@@ -2874,6 +2954,43 @@ int tracing_open_generic(struct inode *inode, struct file *filp)
return 0;
}
+/*
+ * 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_open_generic_tc(struct inode *inode, struct file *filp)
+{
+ struct trace_cpu *tc = inode->i_private;
+ struct trace_array *tr = tc->tr;
+
+ 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 = file->private_data;
@@ -2881,17 +2998,19 @@ static int tracing_release(struct inode *inode, struct file *file)
struct trace_array *tr;
int cpu;
- if (!(file->f_mode & FMODE_READ))
+ /* Writes do not use seq_file, need to grab tr from inode */
+ if (!(file->f_mode & FMODE_READ)) {
+ struct trace_cpu *tc = inode->i_private;
+
+ trace_array_put(tc->tr);
return 0;
+ }
iter = m->private;
tr = iter->tr;
mutex_lock(&trace_types_lock);
- WARN_ON(!tr->ref);
- tr->ref--;
-
for_each_tracing_cpu(cpu) {
if (iter->buffer_iter[cpu])
ring_buffer_read_finish(iter->buffer_iter[cpu]);
@@ -2903,6 +3022,9 @@ static int tracing_release(struct inode *inode, struct file *file)
if (!iter->snapshot)
/* reenable tracing if it was previously enabled */
tracing_start_tr(tr);
+
+ __trace_array_put(tr);
+
mutex_unlock(&trace_types_lock);
mutex_destroy(&iter->mutex);
@@ -2910,20 +3032,49 @@ static int tracing_release(struct inode *inode, struct file *file)
kfree(iter->trace);
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_release_generic_tc(struct inode *inode, struct file *file)
+{
+ struct trace_cpu *tc = inode->i_private;
+ struct trace_array *tr = tc->tr;
+
+ 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_cpu *tc = inode->i_private;
+ struct trace_array *tr = tc->tr;
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_TRUNC)) {
- struct trace_cpu *tc = inode->i_private;
- struct trace_array *tr = tc->tr;
-
if (tc->cpu == RING_BUFFER_ALL_CPUS)
tracing_reset_online_cpus(&tr->trace_buffer);
else
@@ -2931,12 +3082,16 @@ static int tracing_open(struct inode *inode, struct file *file)
}
if (file->f_mode & FMODE_READ) {
- iter = __tracing_open(inode, file, false);
+ iter = __tracing_open(tr, tc, 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;
}
@@ -3293,17 +3448,27 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf,
static int tracing_trace_options_open(struct inode *inode, struct file *file)
{
+ struct trace_array *tr = inode->i_private;
+ int ret;
+
if (tracing_disabled)
return -ENODEV;
- return single_open(file, tracing_trace_options_show, inode->i_private);
+ 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_trace_options_open,
.read = seq_read,
.llseek = seq_lseek,
- .release = single_release,
+ .release = tracing_single_release_tr,
.write = tracing_trace_options_write,
};
@@ -3379,14 +3544,14 @@ static const char readme_msg[] =
"\n snapshot\t\t- Like 'trace' but shows the content of the static snapshot buffer\n"
"\t\t\t Read the contents for more information\n"
#endif
-#ifdef CONFIG_STACKTRACE
+#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 new trace)\n"
#ifdef CONFIG_DYNAMIC_FTRACE
" stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace traces\n"
#endif
-#endif /* CONFIG_STACKTRACE */
+#endif /* CONFIG_STACK_TRACER */
;
static ssize_t
@@ -3791,12 +3956,16 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
if (tracing_disabled)
return -ENODEV;
+ if (trace_array_get(tr) < 0)
+ return -ENODEV;
+
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;
}
@@ -3843,6 +4012,7 @@ out:
fail:
kfree(iter->trace);
kfree(iter);
+ __trace_array_put(tr);
mutex_unlock(&trace_types_lock);
return ret;
}
@@ -3850,6 +4020,8 @@ fail:
static int tracing_release_pipe(struct inode *inode, struct file *file)
{
struct trace_iterator *iter = file->private_data;
+ struct trace_cpu *tc = inode->i_private;
+ struct trace_array *tr = tc->tr;
mutex_lock(&trace_types_lock);
@@ -3863,6 +4035,8 @@ static int tracing_release_pipe(struct inode *inode, struct file *file)
kfree(iter->trace);
kfree(iter);
+ trace_array_put(tr);
+
return 0;
}
@@ -3939,7 +4113,7 @@ static int tracing_wait_pipe(struct file *filp)
*
* iter->pos will be 0 if we haven't read anything.
*/
- if (!tracing_is_enabled() && iter->pos)
+ if (!tracing_is_on() && iter->pos)
break;
}
@@ -4320,6 +4494,8 @@ tracing_free_buffer_release(struct inode *inode, struct file *filp)
/* resize the ring buffer to 0 */
tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS);
+ trace_array_put(tr);
+
return 0;
}
@@ -4328,6 +4504,7 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *fpos)
{
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;
@@ -4387,7 +4564,7 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
local_save_flags(irq_flags);
size = sizeof(*entry) + cnt + 2; /* possible \n added */
- buffer = global_trace.trace_buffer.buffer;
+ buffer = tr->trace_buffer.buffer;
event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size,
irq_flags, preempt_count());
if (!event) {
@@ -4495,10 +4672,20 @@ static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf,
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;
- return single_open(file, tracing_clock_show, inode->i_private);
+ 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 {
@@ -4511,30 +4698,40 @@ struct ftrace_buffer_info {
static int tracing_snapshot_open(struct inode *inode, struct file *file)
{
struct trace_cpu *tc = inode->i_private;
+ struct trace_array *tr = tc->tr;
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);
+ iter = __tracing_open(tr, tc, 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)
- return -ENOMEM;
+ goto out;
iter = kzalloc(sizeof(*iter), GFP_KERNEL);
if (!iter) {
kfree(m);
- return -ENOMEM;
+ goto out;
}
- iter->tr = tc->tr;
+ ret = 0;
+
+ iter->tr = tr;
iter->trace_buffer = &tc->tr->max_buffer;
iter->cpu_file = tc->cpu;
m->private = iter;
file->private_data = m;
}
+out:
+ if (ret < 0)
+ trace_array_put(tr);
return ret;
}
@@ -4616,9 +4813,12 @@ out:
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 tracing_release(inode, file);
+ return ret;
/* If write only, the seq_file is just a stub */
if (m)
@@ -4684,34 +4884,38 @@ static const struct file_operations tracing_pipe_fops = {
};
static const struct file_operations tracing_entries_fops = {
- .open = tracing_open_generic,
+ .open = tracing_open_generic_tc,
.read = tracing_entries_read,
.write = tracing_entries_write,
.llseek = generic_file_llseek,
+ .release = tracing_release_generic_tc,
};
static const struct file_operations tracing_total_entries_fops = {
- .open = tracing_open_generic,
+ .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,
};
static const struct file_operations trace_clock_fops = {
.open = tracing_clock_open,
.read = seq_read,
.llseek = seq_lseek,
- .release = single_release,
+ .release = tracing_single_release_tr,
.write = tracing_clock_write,
};
@@ -4739,18 +4943,22 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp)
struct trace_cpu *tc = inode->i_private;
struct trace_array *tr = tc->tr;
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;
+ }
mutex_lock(&trace_types_lock);
- tr->ref++;
-
info->iter.tr = tr;
info->iter.cpu_file = tc->cpu;
info->iter.trace = tr->current_trace;
@@ -4763,7 +4971,11 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp)
mutex_unlock(&trace_types_lock);
- return nonseekable_open(inode, filp);
+ ret = nonseekable_open(inode, filp);
+ if (ret < 0)
+ trace_array_put(tr);
+
+ return ret;
}
static unsigned int
@@ -4863,8 +5075,7 @@ static int tracing_buffers_release(struct inode *inode, struct file *file)
mutex_lock(&trace_types_lock);
- WARN_ON(!iter->tr->ref);
- iter->tr->ref--;
+ __trace_array_put(iter->tr);
if (info->spare)
ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare);
@@ -5126,9 +5337,10 @@ 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_tc,
.read = tracing_stats_read,
.llseek = generic_file_llseek,
+ .release = tracing_release_generic_tc,
};
#ifdef CONFIG_DYNAMIC_FTRACE
@@ -5612,15 +5824,10 @@ rb_simple_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
struct trace_array *tr = filp->private_data;
- struct ring_buffer *buffer = tr->trace_buffer.buffer;
char buf[64];
int r;
- if (buffer)
- r = ring_buffer_record_is_on(buffer);
- else
- r = 0;
-
+ r = tracer_tracing_is_on(tr);
r = sprintf(buf, "%d\n", r);
return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
@@ -5642,11 +5849,11 @@ rb_simple_write(struct file *filp, const char __user *ubuf,
if (buffer) {
mutex_lock(&trace_types_lock);
if (val) {
- ring_buffer_record_on(buffer);
+ tracer_tracing_on(tr);
if (tr->current_trace->start)
tr->current_trace->start(tr);
} else {
- ring_buffer_record_off(buffer);
+ tracer_tracing_off(tr);
if (tr->current_trace->stop)
tr->current_trace->stop(tr);
}
@@ -5659,9 +5866,10 @@ rb_simple_write(struct file *filp, const char __user *ubuf,
}
static const struct file_operations rb_simple_fops = {
- .open = tracing_open_generic,
+ .open = tracing_open_generic_tr,
.read = rb_simple_read,
.write = rb_simple_write,
+ .release = tracing_release_generic_tr,
.llseek = default_llseek,
};
@@ -5775,8 +5983,10 @@ static int new_instance_create(const char *name)
goto out_free_tr;
ret = event_trace_add_tracer(tr->dir, tr);
- if (ret)
+ if (ret) {
+ debugfs_remove_recursive(tr->dir);
goto out_free_tr;
+ }
init_tracer_debugfs(tr, tr->dir);
@@ -5933,7 +6143,7 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer)
trace_create_file("buffer_total_size_kb", 0444, d_tracer,
tr, &tracing_total_entries_fops);
- trace_create_file("free_buffer", 0644, d_tracer,
+ trace_create_file("free_buffer", 0200, d_tracer,
tr, &tracing_free_buffer_fops);
trace_create_file("trace_marker", 0220, d_tracer,
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 20572ed88c5..e7d643b8a90 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -214,7 +214,6 @@ struct trace_array {
struct dentry *event_dir;
struct list_head systems;
struct list_head events;
- struct task_struct *waiter;
int ref;
};
@@ -224,6 +223,11 @@ enum {
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.
@@ -554,11 +558,6 @@ void tracing_iter_reset(struct trace_iterator *iter, int cpu);
void poll_wait_pipe(struct trace_iterator *iter);
-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,
@@ -680,6 +679,15 @@ extern int trace_selftest_startup_sched_switch(struct tracer *trace,
struct trace_array *tr);
extern int trace_selftest_startup_branch(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);
@@ -774,6 +782,7 @@ print_graph_function_flags(struct trace_iterator *iter, u32 flags)
extern struct list_head ftrace_pids;
#ifdef CONFIG_FUNCTION_TRACER
+extern bool ftrace_filter_param __initdata;