[PATCH] kthread: update stop_machine to use kthread_bind

[Serge E . Hallyn]

Update stop_machine to use the more efficient kthread_bind()
before running task in place of set_cpus_allowed() after.

Signed-off-by: Serge E. Hallyn <serue@xxxxxxxxxx>

---

 kernel/stop_machine.c |   13 +++++++------
 1 files changed, 7 insertions(+), 6 deletions(-)

fe140b494141aefae45a4fa12a4b4e8fef5d8ee3
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index 2dd5a48..698b842 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -26,15 +26,13 @@ static unsigned int stopmachine_num_thre
 static atomic_t stopmachine_thread_ack;
 static DECLARE_MUTEX(stopmachine_mutex);
 
-static int stopmachine(void *cpu)
+static int stopmachine(void)
 {
 	int irqs_disabled = 0;
 	int prepared = 0;
 
-	set_cpus_allowed(current, cpumask_of_cpu((int)(long)cpu));
-
 	/* Ack: we are alive */
-	smp_mb(); /* Theoretically the ack = 0 might not be on this CPU yet. */
+	smp_mb();
 	atomic_inc(&stopmachine_thread_ack);
 
 	/* Simple state machine */
@@ -86,7 +84,8 @@ static void stopmachine_set_state(enum s
 
 static int stop_machine(void)
 {
-	int i, ret = 0;
+	int ret = 0;
+	unsigned int i;
 	struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
 
 	/* One high-prio thread per cpu.  We'll do this one. */
@@ -100,11 +99,13 @@ static int stop_machine(void)
 		struct task_struct *tsk;
 		if (i == raw_smp_processor_id())
 			continue;
-		tsk = kthread_run(stopmachine, (void *)(long)i, "stopmachine");
+		tsk = kthread_create(stopmachine, NULL, "stopmachine");
 		if (IS_ERR(tsk)) {
 			ret = PTR_ERR(tsk);
 			break;
 		}
+		kthread_bind(tsk, i);
+		wake_up_process(tsk);
 		stopmachine_num_threads++;
 	}
 
-- 
1.3.3

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