[PATCH] cpuacct: add a branch prediction

From: Li Zefan
Date: Thu Feb 26 2009 - 02:40:21 EST


cpuacct_charge() is in fast-path, and checking of !cpuacct_susys.active
always returns false after cpuacct has been initialized at system boot.

Signed-off-by: Li Zefan <lizf@xxxxxxxxxxxxxx>
---
kernel/sched.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/kernel/sched.c b/kernel/sched.c
index 410eec4..fd2f7fc 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -9589,7 +9589,7 @@ static void cpuacct_charge(struct task_struct *tsk, u64 cputime)
struct cpuacct *ca;
int cpu;

- if (!cpuacct_subsys.active)
+ if (unlikely(!cpuacct_subsys.active))
return;

cpu = task_cpu(tsk);
--
1.5.4.rc3

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