perf/hwpb: Invoke __perf_event_disable() if interrupts are already disabled
authorK.Prasad <Prasad.Krishnan@gmail.com>
Thu, 2 Aug 2012 08:16:35 +0000 (13:46 +0530)
committerIngo Molnar <mingo@kernel.org>
Tue, 4 Sep 2012 15:29:53 +0000 (17:29 +0200)
commit500ad2d8b01390c98bc6dce068bccfa9534b8212
treea7e1330e5380d4cb4be02820a86fbea1dc0da5c9
parent3ec18cd8b8f8395d0df604c62ab3bc2cf3a966b4
perf/hwpb: Invoke __perf_event_disable() if interrupts are already disabled

While debugging a warning message on PowerPC while using hardware
breakpoints, it was discovered that when perf_event_disable is invoked
through hw_breakpoint_handler function with interrupts disabled, a
subsequent IPI in the code path would trigger a WARN_ON_ONCE message in
smp_call_function_single function.

This patch calls __perf_event_disable() when interrupts are already
disabled, instead of perf_event_disable().

Reported-by: Edjunior Barbosa Machado <emachado@linux.vnet.ibm.com>
Signed-off-by: K.Prasad <Prasad.Krishnan@gmail.com>
[naveen.n.rao@linux.vnet.ibm.com: v3: Check to make sure we target current task]
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120802081635.5811.17737.stgit@localhost.localdomain
[ Fixed build error on MIPS. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
include/linux/perf_event.h
kernel/events/core.c
kernel/events/hw_breakpoint.c