diff options
| author | Steven Rostedt <srostedt@redhat.com> | 2009-01-21 15:24:56 -0500 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-01-22 10:27:16 +0100 |
| commit | 97b17efe4537e11bf6669106cfe4ee2c5331b267 (patch) | |
| tree | 46310b25ea38628fc631d4c4c248ebe66426036f | |
| parent | 5bc4564b224c3d9fe6dddafa25f56059bd978231 (diff) | |
ring-buffer: do not swap if recording is disabled
If the ring buffer recording has been disabled. Do not let
swapping of ring buffers occur. Simply return -EAGAIN.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | kernel/trace/ring_buffer.c | 15 | ||||
| -rw-r--r-- | kernel/trace/trace.c | 2 |
2 files changed, 16 insertions, 1 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 0b9de5a3d69..890020e28a3 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -2266,9 +2266,24 @@ int ring_buffer_swap_cpu(struct ring_buffer *buffer_a, if (buffer_a->pages != buffer_b->pages) return -EINVAL; + if (ring_buffer_flags != RB_BUFFERS_ON) + return -EAGAIN; + + if (atomic_read(&buffer_a->record_disabled)) + return -EAGAIN; + + if (atomic_read(&buffer_b->record_disabled)) + return -EAGAIN; + cpu_buffer_a = buffer_a->buffers[cpu]; cpu_buffer_b = buffer_b->buffers[cpu]; + if (atomic_read(&cpu_buffer_a->record_disabled)) + return -EAGAIN; + + if (atomic_read(&cpu_buffer_b->record_disabled)) + return -EAGAIN; + /* * We can't do a synchronize_sched here because this * function can be called in atomic context. diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 220c264e311..757ae6f7e64 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -415,7 +415,7 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) ftrace_enable_cpu(); - WARN_ON_ONCE(ret); + WARN_ON_ONCE(ret && ret != -EAGAIN); __update_max_tr(tr, tsk, cpu); __raw_spin_unlock(&ftrace_max_lock); |