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| author | Steven Rostedt (Red Hat) <rostedt@goodmis.org> | 2013-03-26 17:33:00 -0400 |
|---|---|---|
| committer | Steven Rostedt <rostedt@rostedt.homelinux.com> | 2013-04-08 12:24:22 -0400 |
| commit | 2930e04d00e113ae24bb2b7c2b58de7b648a62c7 (patch) | |
| tree | 60dc173d8370ec69d48f04f074ca78fb152d0c1f /kernel | |
| parent | fd4a5aef002bb57e8a35ed34d8a878034b9bde94 (diff) | |
| download | lwn-2930e04d00e113ae24bb2b7c2b58de7b648a62c7.tar.gz lwn-2930e04d00e113ae24bb2b7c2b58de7b648a62c7.zip | |
tracing: Fix race with update_max_tr_single and changing tracers
The commit 34600f0e9 "tracing: Fix race with max_tr and changing tracers"
fixed the updating of the main buffers with the race of changing
tracers, but left out the fix to the updating of just a per cpu buffer.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel')
| -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 4f1dade56981..7ba7fc76f9eb 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -744,8 +744,11 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) return; WARN_ON_ONCE(!irqs_disabled()); - if (WARN_ON_ONCE(!current_trace->allocated_snapshot)) + if (!current_trace->allocated_snapshot) { + /* Only the nop tracer should hit this when disabling */ + WARN_ON_ONCE(current_trace != &nop_trace); return; + } arch_spin_lock(&ftrace_max_lock); |