Commit 6adaad14 authored Mar 16, 2009 by Steven Rostedt

tracing: stop comm recording on tracing off



Impact: fix for losing comms in trace

The command lines of tasks are cached at sched switch to not need
to record them at every trace point.  Disabling the tracing on stops
the recording of traces, but does not stop the caching of command lines.
When the tracing is off the cache may overflow and cause the tracing
to show incorrect tasks matching the PIDs.

This patch disables prevents updates to the comm cache when the ring buffer
is off.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>

parent 4ca53085

kernel/trace/trace.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -797,7 +797,7 @@ void trace_find_cmdline(int pid, char comm[])

		void tracing_record_cmdline(struct task_struct *tsk)
		{
		if (atomic_read(&trace_record_cmdline_disabled))
		if (atomic_read(&trace_record_cmdline_disabled) \|\| !tracing_is_on())
		return;

		trace_save_cmdline(tsk);

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