2010-01-08 15:27:42

by Jamie Iles

Subject: [PATCH] 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 <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Russell King - ARM Linux <[email protected]>
---
kernel/sched.c | 6 ++++++
1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/kernel/sched.c b/kernel/sched.c
index 22c14eb..78132b4 100644
--- 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);
--
1.6.5.4

2010-01-13 10:41:09

by Jamie Iles

Subject: [tip:perf/core] sched/perf: Make sure irqs are disabled for perf_event_task_sched_in()

Commit-ID: 8381f65d097dad90416808314737dd7d3ae38ea9
Gitweb: http://git.kernel.org/tip/8381f65d097dad90416808314737dd7d3ae38ea9
Author: Jamie Iles <[email protected]>
AuthorDate: Fri, 8 Jan 2010 15:27:33 +0000
Committer: Ingo Molnar <[email protected]>
CommitDate: Wed, 13 Jan 2010 10:43:08 +0100

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 <[email protected]>
Acked-by: Peter Zijlstra <[email protected]>
Cc: Russell King - ARM Linux <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
---
kernel/sched.c | 6 ++++++
1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/kernel/sched.c b/kernel/sched.c
index e507af0..c3ad342 100644
--- 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);