diff options
| author | Steven Rostedt <srostedt@redhat.com> | 2009-03-12 11:33:20 -0400 |
|---|---|---|
| committer | Steven Rostedt <srostedt@redhat.com> | 2009-03-12 21:14:58 -0400 |
| commit | 1027fcb206a0fb8348e63aff078c74bdee1c2698 (patch) | |
| tree | 05e858e410fdb30865a11c78e2bb9bb0a12f55ba | |
| parent | a123c52b46a1f84bcec3dc963351896c6d6afaf7 (diff) | |
tracing: protect ring_buffer_expanded with trace_types_lock
Impact: prevent races with ring_buffer_expanded
This patch places the expanding of the tracing buffer under the
protection of the trace_types_lock mutex. It is highly unlikely
that there would be any contention, but better safe than sorry.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
| -rw-r--r-- | kernel/trace/trace.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index c61ee85c50b..04ab8243a13 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2391,8 +2391,10 @@ int tracing_update_buffers(void) { int ret = 0; + mutex_lock(&trace_types_lock); if (!ring_buffer_expanded) ret = tracing_resize_ring_buffer(trace_buf_size); + mutex_unlock(&trace_types_lock); return ret; } @@ -2412,6 +2414,8 @@ static int tracing_set_tracer(const char *buf) struct tracer *t; int ret = 0; + mutex_lock(&trace_types_lock); + if (!ring_buffer_expanded) { ret = tracing_resize_ring_buffer(trace_buf_size); if (ret < 0) @@ -2419,7 +2423,6 @@ static int tracing_set_tracer(const char *buf) ret = 0; } - mutex_lock(&trace_types_lock); for (t = trace_types; t; t = t->next) { if (strcmp(t->name, buf) == 0) break; |