sched: Clean up ttwu() stats
Peter Zijlstra [Tue, 5 Apr 2011 15:23:43 +0000 (17:23 +0200)]
Collect all ttwu() stat code into a single function and ensure its
always called for an actual wakeup (changing p->state to
TASK_RUNNING).

Reviewed-by: Frank Rowand <frank.rowand@am.sony.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110405152728.908177058@chello.nl

kernel/sched.c

index 3919aa4..4481638 100644 (file)
@@ -2406,20 +2406,43 @@ static void update_avg(u64 *avg, u64 sample)
 }
 #endif
 
-static inline void ttwu_activate(struct task_struct *p, struct rq *rq,
-                                bool is_sync, bool is_migrate, bool is_local,
-                                unsigned long en_flags)
+static void
+ttwu_stat(struct rq *rq, struct task_struct *p, int cpu, int wake_flags)
 {
+#ifdef CONFIG_SCHEDSTATS
+#ifdef CONFIG_SMP
+       int this_cpu = smp_processor_id();
+
+       if (cpu == this_cpu) {
+               schedstat_inc(rq, ttwu_local);
+               schedstat_inc(p, se.statistics.nr_wakeups_local);
+       } else {
+               struct sched_domain *sd;
+
+               schedstat_inc(p, se.statistics.nr_wakeups_remote);
+               for_each_domain(this_cpu, sd) {
+                       if (cpumask_test_cpu(cpu, sched_domain_span(sd))) {
+                               schedstat_inc(sd, ttwu_wake_remote);
+                               break;
+                       }
+               }
+       }
+#endif /* CONFIG_SMP */
+
+       schedstat_inc(rq, ttwu_count);
        schedstat_inc(p, se.statistics.nr_wakeups);
-       if (is_sync)
+
+       if (wake_flags & WF_SYNC)
                schedstat_inc(p, se.statistics.nr_wakeups_sync);
-       if (is_migrate)
+
+       if (cpu != task_cpu(p))
                schedstat_inc(p, se.statistics.nr_wakeups_migrate);
-       if (is_local)
-               schedstat_inc(p, se.statistics.nr_wakeups_local);
-       else
-               schedstat_inc(p, se.statistics.nr_wakeups_remote);
 
+#endif /* CONFIG_SCHEDSTATS */
+}
+
+static void ttwu_activate(struct rq *rq, struct task_struct *p, int en_flags)
+{
        activate_task(rq, p, en_flags);
 
        /* if a worker is waking up, notify workqueue */
@@ -2481,12 +2504,12 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
        if (!(p->state & state))
                goto out;
 
+       cpu = task_cpu(p);
+
        if (p->se.on_rq)
                goto out_running;
 
-       cpu = task_cpu(p);
        orig_cpu = cpu;
-
 #ifdef CONFIG_SMP
        if (unlikely(task_running(rq, p)))
                goto out_activate;
@@ -2527,27 +2550,12 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
        WARN_ON(task_cpu(p) != cpu);
        WARN_ON(p->state != TASK_WAKING);
 
-#ifdef CONFIG_SCHEDSTATS
-       schedstat_inc(rq, ttwu_count);
-       if (cpu == this_cpu)
-               schedstat_inc(rq, ttwu_local);
-       else {
-               struct sched_domain *sd;
-               for_each_domain(this_cpu, sd) {
-                       if (cpumask_test_cpu(cpu, sched_domain_span(sd))) {
-                               schedstat_inc(sd, ttwu_wake_remote);
-                               break;
-                       }
-               }
-       }
-#endif /* CONFIG_SCHEDSTATS */
-
 out_activate:
 #endif /* CONFIG_SMP */
-       ttwu_activate(p, rq, wake_flags & WF_SYNC, orig_cpu != cpu,
-                     cpu == this_cpu, en_flags);
+       ttwu_activate(rq, p, en_flags);
 out_running:
        ttwu_post_activation(p, rq, wake_flags);
+       ttwu_stat(rq, p, cpu, wake_flags);
        success = 1;
 out:
        task_rq_unlock(rq, &flags);
@@ -2575,14 +2583,11 @@ static void try_to_wake_up_local(struct task_struct *p)
        if (!(p->state & TASK_NORMAL))
                return;
 
-       if (!p->se.on_rq) {
-               if (likely(!task_running(rq, p))) {
-                       schedstat_inc(rq, ttwu_count);
-                       schedstat_inc(rq, ttwu_local);
-               }
-               ttwu_activate(p, rq, false, false, true, ENQUEUE_WAKEUP);
-       }
+       if (!p->se.on_rq)
+               ttwu_activate(rq, p, ENQUEUE_WAKEUP);
+
        ttwu_post_activation(p, rq, 0);
+       ttwu_stat(rq, p, smp_processor_id(), 0);
 }
 
 /**