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* [PATCH] sched, x86: Optimize branch hint in __switch_to()
@ 2009-11-29 11:55 Tim Blechmann
  0 siblings, 0 replies; only message in thread
From: Tim Blechmann @ 2009-11-29 11:55 UTC (permalink / raw)
  To: linux-kernel, x86


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Branch hint profiling on my nehalem machine showed 89%
incorrect branch hints:

31032542 270070841  89 __switch_to                    process_64.c         440

Signed-off-by: Tim Blechmann <tim@klingt.org>
---
 arch/x86/kernel/process_64.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)



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diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index c8d0ece..88068b3 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -437,7 +437,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 	 * reload when it has changed.  When prev process used 64bit
 	 * base always reload to avoid an information leak.
 	 */
-	if (unlikely(fsindex | next->fsindex | prev->fs)) {
+	if (fsindex | next->fsindex | prev->fs) {
 		loadsegment(fs, next->fsindex);
 		/*
 		 * Check if the user used a selector != 0; if yes


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