linux-kernel - [PATCH 2/5] sched.c: change branch hint

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Date:	Tue, 24 Nov 2009 11:55:27 +0100
From:	Tim Blechmann <tim@...ngt.org>
To:	linux-kernel@...r.kernel.org
Subject: [PATCH 2/5] sched.c: change branch hint

branch hint profiling of my nehalem machine, showed over 90% incorrect
branch hints:

10420275 170645395  94 context_switch                 sched.c
   3043
10408421 171098521  94 context_switch                 sched.c
   3050

Signed-off-by: Tim Blechmann <tim@...ngt.org>
---
 kernel/sched.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/sched.c b/kernel/sched.c
index c78dcfe..2a78b38 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3040,14 +3040,14 @@ context_switch(struct rq *rq, struct task_struct
*prev,
 	 */
 	arch_start_context_switch(prev);
 -	if (unlikely(!mm)) {
+	if (likely(!mm)) {
 		next->active_mm = oldmm;
 		atomic_inc(&oldmm->mm_count);
 		enter_lazy_tlb(oldmm, next);
 	} else
 		switch_mm(oldmm, mm, next);
 -	if (unlikely(!prev->mm)) {
+	if (likely(!prev->mm)) {
 		prev->active_mm = NULL;
 		rq->prev_mm = oldmm;
 	}
-- 
1.6.4.2



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