ARM: 6352/1: perf: fix event validation
authorWill Deacon <will.deacon@arm.com>
Thu, 2 Sep 2010 08:32:08 +0000 (09:32 +0100)
committerRussell King <rmk+kernel@arm.linux.org.uk>
Thu, 2 Sep 2010 15:36:42 +0000 (16:36 +0100)
The validate_event function in the ARM perf events backend has the
following problems:

1.) Events that are disabled count towards the cost.
2.) Events associated with other PMUs [for example, software events or
    breakpoints] do not count towards the cost, but do fail validation,
    causing the group to fail.

This patch changes validate_event so that it ignores events in the
PERF_EVENT_STATE_OFF state or that are scheduled for other PMUs.

Reported-by: Pawel Moll <pawel.moll@arm.com>
Acked-by: Jamie Iles <jamie.iles@picochip.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/arm/kernel/perf_event.c

index e213925..ecbb028 100644 (file)
@@ -319,8 +319,8 @@ validate_event(struct cpu_hw_events *cpuc,
 {
        struct hw_perf_event fake_event = event->hw;
 
-       if (event->pmu && event->pmu != &pmu)
-               return 0;
+       if (event->pmu != &pmu || event->state <= PERF_EVENT_STATE_OFF)
+               return 1;
 
        return armpmu->get_event_idx(cpuc, &fake_event) >= 0;
 }