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Subject[PATCH] schedule: use unlikely()
A small patch for schedule(), so that the code goes straght in the common
case.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>

---
include/linux/blkdev.h | 2 +-
kernel/sched/core.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

Index: linux-2.6/include/linux/blkdev.h
===================================================================
--- linux-2.6.orig/include/linux/blkdev.h
+++ linux-2.6/include/linux/blkdev.h
@@ -1308,7 +1308,7 @@ static inline bool blk_needs_flush_plug(
{
struct blk_plug *plug = tsk->plug;

- return plug &&
+ return unlikely(plug != NULL) &&
(!list_empty(&plug->list) ||
!list_empty(&plug->mq_list) ||
!list_empty(&plug->cb_list));
Index: linux-2.6/kernel/sched/core.c
===================================================================
--- linux-2.6.orig/kernel/sched/core.c
+++ linux-2.6/kernel/sched/core.c
@@ -3405,7 +3405,7 @@ void __noreturn do_task_dead(void)

static inline void sched_submit_work(struct task_struct *tsk)
{
- if (!tsk->state || tsk_is_pi_blocked(tsk))
+ if (!tsk->state || unlikely(tsk_is_pi_blocked(tsk)))
return;
/*
* If we are going to sleep and we have plugged IO queued,
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