Commit 621968cd authored Sep 04, 2009 by Steven Rostedt Committed by Steven Rostedt Sep 04, 2009

tracing: disable buffers and synchronize_sched before resetting

Resetting the ring buffers while traces are happening can corrupt
the ring buffer and disable it (no kernel crash to worry about).

The safest thing to do is disable the ring buffers, call synchronize_sched()
to wait for all current writers to finish and then reset the buffer.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

parent b8de7bd1

kernel/trace/trace.c

+8 −0

Original line number	Diff line number	Diff line
		@@ -658,12 +658,20 @@ void tracing_reset(struct trace_array *tr, int cpu)

		void tracing_reset_online_cpus(struct trace_array *tr)
		{
		struct ring_buffer *buffer = tr->buffer;
		int cpu;

		ring_buffer_record_disable(buffer);

		/* Make sure all commits have finished */
		synchronize_sched();

		tr->time_start = ftrace_now(tr->cpu);

		for_each_online_cpu(cpu)
		tracing_reset(tr, cpu);

		ring_buffer_record_enable(buffer);
		}

		void tracing_reset_current(int cpu)