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>
This commit is contained in:
Steven Rostedt (Red Hat) 2013-03-26 17:33:00 -04:00 committed by Steven Rostedt
parent fd4a5aef00
commit 2930e04d00

View File

@ -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);