[PATCH] sched: Optimize branch hint in context_switch()

[Tim Blechmann <tim@klingt.org>]

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Branch hint profiling on my nehalem machine showed 88%
incorrect branch hints:

42017484 326957902  88 context_switch                 sched.c              3043
42038493 326953687  88 context_switch                 sched.c              3050

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



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


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