Files
linux/kernel
Peter Zijlstra 547e9fd7d3 perf: Annotate cpuctx->ctx.mutex to avoid a lockdep splat
Lockdep spotted:

	loop_1b_instruc/1899 is trying to acquire lock:
	 (event_mutex){+.+.+.}, at: [<ffffffff810e1908>] perf_trace_init+0x3b/0x2f7

	but task is already holding lock:
	 (&ctx->mutex){+.+.+.}, at: [<ffffffff810eb45b>] perf_event_init_context+0xc0/0x218

	which lock already depends on the new lock.

	the existing dependency chain (in reverse order) is:

	-> #3 (&ctx->mutex){+.+.+.}:
	-> #2 (cpu_hotplug.lock){+.+.+.}:
	-> #1 (module_mutex){+.+...}:
	-> #0 (event_mutex){+.+.+.}:

But because the deadlock would be cpuhotplug (cpu-event) vs fork
(task-event) it cannot, in fact, happen. We can annotate this by giving the
perf_event_context used for the cpuctx a different lock class from those
used by tasks.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-01-21 16:32:42 +01:00
..
2010-12-22 18:57:02 +01:00
2011-01-13 17:32:31 -08:00
2010-08-09 16:48:42 -04:00
2010-07-14 11:29:46 +02:00
2010-10-30 01:42:19 -04:00
2010-11-03 13:49:58 -04:00
2010-10-30 01:42:19 -04:00
2010-10-30 08:45:43 -04:00
2010-10-29 04:17:06 -04:00
2011-01-13 17:32:43 -08:00
2010-12-16 11:36:43 +01:00
2010-11-01 15:38:34 -04:00
2010-10-01 10:50:58 -07:00
2010-10-18 18:44:26 +02:00
2010-08-11 23:04:20 +09:30
2010-08-19 17:18:02 -07:00
2010-11-18 13:27:46 +01:00
2011-01-13 08:03:08 -08:00
2011-01-13 08:03:18 -08:00
2010-12-29 11:31:38 -08:00