sched/perf: Make sure irqs are disabled for perf_event_task_sched_in()

perf_event_task_sched_in() expects interrupts to be disabled,
but on architectures with __ARCH_WANT_INTERRUPTS_ON_CTXSW
defined, this isn't true. If this is defined, disable irqs
around the call in finish_task_switch().

Signed-off-by: Jamie Iles <jamie.iles@picochip.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
LKML-Reference: <1262964453-27370-1-git-send-email-jamie.iles@picochip.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/kernel/sched.c b/kernel/sched.c
index e507af0..c3ad342 100644 (file)
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -2783,7 +2783,13 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev)
         */
        prev_state = prev->state;
        finish_arch_switch(prev);
+#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
+       local_irq_disable();
+#endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */
        perf_event_task_sched_in(current);
+#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
+       local_irq_enable();
+#endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */
        finish_lock_switch(rq, prev);
 
        fire_sched_in_preempt_notifiers(current);