Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6

[pandora-kernel.git] / kernel / sched_stats.h

diff --git a/kernel/sched_stats.h b/kernel/sched_stats.h
index 80179ef..8385d43 100644 (file)
--- a/kernel/sched_stats.h
+++ b/kernel/sched_stats.h
@@ -118,6 +118,13 @@ rq_sched_info_depart(struct rq *rq, unsigned long long delta)
        if (rq)
                rq->rq_sched_info.cpu_time += delta;
 }
+
+static inline void
+rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
+{
+       if (rq)
+               rq->rq_sched_info.run_delay += delta;
+}
 # define schedstat_inc(rq, field)      do { (rq)->field++; } while (0)
 # define schedstat_add(rq, field, amt) do { (rq)->field += (amt); } while (0)
 # define schedstat_set(var, val)       do { var = (val); } while (0)
@@ -126,6 +133,9 @@ static inline void
 rq_sched_info_arrive(struct rq *rq, unsigned long long delta)
 {}
 static inline void
+rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
+{}
+static inline void
 rq_sched_info_depart(struct rq *rq, unsigned long long delta)
 {}
 # define schedstat_inc(rq, field)      do { } while (0)
@@ -134,6 +144,11 @@ rq_sched_info_depart(struct rq *rq, unsigned long long delta)
 #endif
 
 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
+static inline void sched_info_reset_dequeued(struct task_struct *t)
+{
+       t->sched_info.last_queued = 0;
+}
+
 /*
  * Called when a process is dequeued from the active array and given
  * the cpu.  We should note that with the exception of interactive
@@ -143,15 +158,22 @@ rq_sched_info_depart(struct rq *rq, unsigned long long delta)
  * active queue, thus delaying tasks in the expired queue from running;
  * see scheduler_tick()).
  *
- * This function is only called from sched_info_arrive(), rather than
- * dequeue_task(). Even though a task may be queued and dequeued multiple
- * times as it is shuffled about, we're really interested in knowing how
- * long it was from the *first* time it was queued to the time that it
- * finally hit a cpu.
+ * Though we are interested in knowing how long it was from the *first* time a
+ * task was queued to the time that it finally hit a cpu, we call this routine
+ * from dequeue_task() to account for possible rq->clock skew across cpus. The
+ * delta taken on each cpu would annul the skew.
  */
 static inline void sched_info_dequeued(struct task_struct *t)
 {
-       t->sched_info.last_queued = 0;
+       unsigned long long now = task_rq(t)->clock, delta = 0;
+
+       if (unlikely(sched_info_on()))
+               if (t->sched_info.last_queued)
+                       delta = now - t->sched_info.last_queued;
+       sched_info_reset_dequeued(t);
+       t->sched_info.run_delay += delta;
+
+       rq_sched_info_dequeued(task_rq(t), delta);
 }
 
 /*
@@ -165,7 +187,7 @@ static void sched_info_arrive(struct task_struct *t)
 
        if (t->sched_info.last_queued)
                delta = now - t->sched_info.last_queued;
-       sched_info_dequeued(t);
+       sched_info_reset_dequeued(t);
        t->sched_info.run_delay += delta;
        t->sched_info.last_arrival = now;
        t->sched_info.pcount++;
@@ -242,7 +264,9 @@ sched_info_switch(struct task_struct *prev, struct task_struct *next)
                __sched_info_switch(prev, next);
 }
 #else
-#define sched_info_queued(t)           do { } while (0)
-#define sched_info_switch(t, next)     do { } while (0)
+#define sched_info_queued(t)                   do { } while (0)
+#define sched_info_reset_dequeued(t)   do { } while (0)
+#define sched_info_dequeued(t)                 do { } while (0)
+#define sched_info_switch(t, next)             do { } while (0)
 #endif /* CONFIG_SCHEDSTATS || CONFIG_TASK_DELAY_ACCT */