Commit 18aecd36 authored Mar 18, 2009 by Thomas Gleixner Committed by Ingo Molnar Mar 18, 2009

tracing: stop command line recording when tracing is disabled



Impact: prevent overwrite of command line entries

When the tracer is stopped the command line recording continues to
record. The check for tracing_is_on() is not sufficient here as the
ringbuffer status is not affected by setting
debug/tracing/tracing_enabled to 0. On a non idle system this can
result in the loss of the command line information for the stopped
trace, which makes the trace harder to read and analyse.

Check tracer_enabled to allow further recording.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

parent 03418c7e

kernel/trace/trace.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -797,7 +797,8 @@ void trace_find_cmdline(int pid, char comm[])

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

		trace_save_cmdline(tsk);

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