diff options
author | Steven Rostedt <srostedt@redhat.com> | 2009-03-12 11:21:08 -0400 |
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committer | Steven Rostedt <srostedt@redhat.com> | 2009-03-12 21:14:58 -0400 |
commit | a123c52b46a1f84bcec3dc963351896c6d6afaf7 (patch) | |
tree | bbfea12d2234930fd67644fa281d11c8ab850460 /kernel | |
parent | 51b643b404827d8fde60d7953773a42d46ca87e0 (diff) | |
download | op-kernel-dev-a123c52b46a1f84bcec3dc963351896c6d6afaf7.zip op-kernel-dev-a123c52b46a1f84bcec3dc963351896c6d6afaf7.tar.gz |
tracing: fix comments about trace buffer resizing
Impact: cleanup
Some of the comments about the trace buffer resizing is gobbledygook.
And I wonder why people question if I'm a native English speaker.
This patch makes the comments make a bit more sense.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/trace/trace.c | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index c3946a6..c61ee85 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2336,7 +2336,8 @@ static int tracing_resize_ring_buffer(unsigned long size) /* * If kernel or user changes the size of the ring buffer - * it get completed. + * we use the size that was given, and we can forget about + * expanding it later. */ ring_buffer_expanded = 1; @@ -2351,8 +2352,20 @@ static int tracing_resize_ring_buffer(unsigned long size) r = ring_buffer_resize(global_trace.buffer, global_trace.entries); if (r < 0) { - /* AARGH! We are left with different - * size max buffer!!!! */ + /* + * AARGH! We are left with different + * size max buffer!!!! + * The max buffer is our "snapshot" buffer. + * When a tracer needs a snapshot (one of the + * latency tracers), it swaps the max buffer + * with the saved snap shot. We succeeded to + * update the size of the main buffer, but failed to + * update the size of the max buffer. But when we tried + * to reset the main buffer to the original size, we + * failed there too. This is very unlikely to + * happen, but if it does, warn and kill all + * tracing. + */ WARN_ON(1); tracing_disabled = 1; } |