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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-06-12 21:07:25 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-06-12 21:07:25 -0700 |
| commit | 8841c8b3c4c4d9a9f2a6d30b463ad8d2c6e2f0ea (patch) | |
| tree | dae6cf40947c0eab290da7165e6eac2818a3ab92 /kernel/trace/ring_buffer.c | |
| parent | b7c8c1945cfbcfb9d60f5be957b4339c6eee4201 (diff) | |
| parent | da9c3413a27be5ba6f996e90495c836dd30b8841 (diff) | |
Merge tag 'trace-3.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing cleanups and bugfixes from Steven Rostedt:
"One bug fix that goes back to 3.10. Accessing a non existent buffer
if "possible cpus" is greater than actual CPUs (including offline
CPUs).
Namhyung Kim did some reviews of the patches I sent this merge window
and found a memory leak and had a few clean ups"
* tag 'trace-3.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix check of ftrace_trace_arrays list_empty() check
tracing: Fix leak of per cpu max data in instances
tracing: Cleanup saved_cmdlines_size changes
ring-buffer: Check if buffer exists before polling
Diffstat (limited to 'kernel/trace/ring_buffer.c')
| -rw-r--r-- | kernel/trace/ring_buffer.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index c634868c2921..7c56c3d06943 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -543,7 +543,7 @@ static void rb_wake_up_waiters(struct irq_work *work) * 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. */ -void ring_buffer_wait(struct ring_buffer *buffer, int cpu) +int ring_buffer_wait(struct ring_buffer *buffer, int cpu) { struct ring_buffer_per_cpu *cpu_buffer; DEFINE_WAIT(wait); @@ -557,6 +557,8 @@ void ring_buffer_wait(struct ring_buffer *buffer, int cpu) 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; } @@ -591,6 +593,7 @@ void ring_buffer_wait(struct ring_buffer *buffer, int cpu) schedule(); finish_wait(&work->waiters, &wait); + return 0; } /** |