[RFC][PATCH 15/18] sched: Remove rq argument from ttwu_stat()

[Peter Zijlstra]

In order to call ttwu_stat() without holding rq->lock we must remove
its rq argument. Since we need to change rq stats, account to the
local rq instead of the task rq, this is safe since we have IRQs
disabled.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
---
 kernel/sched.c |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

Index: linux-2.6/kernel/sched.c
===================================================================
--- linux-2.6.orig/kernel/sched.c
+++ linux-2.6/kernel/sched.c
@@ -2367,10 +2367,11 @@ static void update_avg(u64 *avg, u64 sam
 #endif
 
 static void
-ttwu_stat(struct rq *rq, struct task_struct *p, int cpu, int wake_flags)
+ttwu_stat(struct task_struct *p, int cpu, int wake_flags)
 {
 #ifdef CONFIG_SCHEDSTATS
 	int this_cpu = smp_processor_id();
+	struct rq *rq = this_rq();
 
 	schedstat_inc(rq, ttwu_count);
 	schedstat_inc(p, se.statistics.nr_wakeups);
@@ -2491,9 +2492,10 @@ try_to_wake_up(struct task_struct *p, un
 	activate_task(rq, p, ENQUEUE_WAKEUP | ENQUEUE_WAKING);
 out_running:
 	ttwu_post_activation(p, rq, wake_flags);
-	ttwu_stat(rq, p, cpu, wake_flags);
 	success = 1;
 	__task_rq_unlock(rq);
+
+	ttwu_stat(p, cpu, wake_flags);
 out:
 	raw_spin_unlock_irqrestore(&p->pi_lock, flags);
 	put_cpu();
@@ -2527,7 +2529,7 @@ static void try_to_wake_up_local(struct 
 		activate_task(rq, p, ENQUEUE_WAKEUP);
 
 	ttwu_post_activation(p, rq, 0);
-	ttwu_stat(rq, p, smp_processor_id(), 0);
+	ttwu_stat(p, smp_processor_id(), 0);
 out:
 	raw_spin_unlock(&p->pi_lock);
 }


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/