[patch 3/4] BFS 420: add task state check in ttwu

[Hillf Danton]

If the given state does not match task, no bother acquiring the global
runqueue lock.

--- a/kernel/sched/bfs.c	Mon May 14 20:50:38 2012
+++ b/kernel/sched/bfs.c	Fri May 25 20:28:00 2012
@@ -1583,6 +1583,8 @@ static bool try_to_wake_up(struct task_s
 	/* This barrier is undocumented, probably for p->state? ãã */
 	smp_wmb();

+	if (!(p->state & state))
+		goto out;
 	/*
 	 * No need to do time_lock_grq as we only need to update the rq clock
 	 * if we activate the task
@@ -1597,14 +1599,14 @@ static bool try_to_wake_up(struct task_s
 	if (task_queued(p) || task_running(p))
 		goto out_running;

-	ttwu_activate(p, rq, wake_flags & WF_SYNC);
+	ttwu_activate(p, rq, !!(wake_flags & WF_SYNC));
 	success = true;

 out_running:
 	ttwu_post_activation(p, rq, success);
 out_unlock:
 	task_grq_unlock(&flags);
-
+out:
 	ttwu_stat(p, cpu, success);

 	put_cpu();
--
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