[PATCH] stop_machine: disable preempt in stop machine path

[Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>]

We can disable preempt in stop_cpu(), It can reduce the cpu's waiting time
and make stop_machine path faster.

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
---
 kernel/stop_machine.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index 912823e..feaa947 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -68,7 +68,7 @@ static void stop_cpu(struct work_struct *unused)
 {
 	enum stopmachine_state curstate = STOPMACHINE_NONE;
 	struct stop_machine_data *smdata = &idle;
-	int cpu = smp_processor_id();
+	int cpu = get_cpu();
 	int err;
 
 	if (!active_cpus) {
@@ -103,6 +103,7 @@ static void stop_cpu(struct work_struct *unused)
 		}
 	} while (curstate != STOPMACHINE_EXIT);
 
+	put_cpu();
 	local_irq_enable();
 }
 
-- 
1.6.1.2