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Subject[tip:sched/core] Revert "sched, x86: Optimize branch hint in __switch_to()"
Commit-ID:  be8147e68625a1adb111acfd6b98a492be4b74d0
Gitweb: http://git.kernel.org/tip/be8147e68625a1adb111acfd6b98a492be4b74d0
Author: Tim Blechmann <tim@klingt.org>
AuthorDate: Wed, 2 Dec 2009 12:32:10 +0100
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Wed, 2 Dec 2009 12:38:03 +0100

Revert "sched, x86: Optimize branch hint in __switch_to()"

This reverts commit a3a1de0c34de6f5f8332cd6151c46af7813c0fcb.

Commit 8ec6993d9f7d961014af970ded57542961fe9ad9 cleared the es
and ds selectors, so the original branch hints are correct now.
Therefore the branch hint doesn't need to be removed.

Signed-off-by: Tim Blechmann <tim@klingt.org>
LKML-Reference: <4B16503A.8030508@klingt.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
arch/x86/kernel/process_64.c | 5 +++--
1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 93c501d..eb62cbc 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -406,10 +406,11 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
* This won't pick up thread selector changes, but I guess that is ok.
*/
savesegment(es, prev->es);
- if (next->es | prev->es)
+ if (unlikely(next->es | prev->es))
loadsegment(es, next->es);
+
savesegment(ds, prev->ds);
- if (next->ds | prev->ds)
+ if (unlikely(next->ds | prev->ds))
loadsegment(ds, next->ds);



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