[PATCH 2/2] tracing: use nowakeup version of commit for function event trace tests

[Steven Rostedt <rostedt@goodmis.org>]

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From: Steven Rostedt <srostedt@redhat.com>

The startup tests for the event tracer also runs with the function
tracer enabled. The "wakeup" version of the trace commit was used
which can grab spinlocks. If a task was preempted by an NMI
that called a function being traced, it could deadlock due to the
function tracer trying to grab the same lock.

Thanks to Frederic Weisbecker for pointing out where the bug was.

Reported-by: Ingo Molnar <mingo@elte.hu>
Reported-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 kernel/trace/trace_events.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 98daf5d..672b195 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -1164,7 +1164,7 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip)
 	entry->ip			= ip;
 	entry->parent_ip		= parent_ip;
 
-	trace_current_buffer_unlock_commit(event, flags, pc);
+	trace_nowake_buffer_unlock_commit(event, flags, pc);
 
  out:
 	atomic_dec(&per_cpu(test_event_disable, cpu));
-- 
1.6.2.1

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