sched: fix delay accounting regression

Fix the delay accounting regression introduced by commit
75d4ef16a6aa84f708188bada182315f80aab6fa. rq no longer has sched_info
data associated with it. task_struct sched_info structure is used by delay
accounting to provide back statistics to user space.

also remove direct use of sched_clock() (which is not a valid thing to
do anymore) and use rq->clock instead.

Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 6 insertions, 5 deletions

diff --git a/kernel/sched_stats.h b/kernel/sched_stats.h
index ef1a7df80ea2..630178e53bb6 100644
--- a/kernel/sched_stats.h
+++ b/kernel/sched_stats.h
@@ -127,7 +127,7 @@ rq_sched_info_depart(struct rq *rq, unsigned long long delta)
 # define schedstat_set(var, val)        do { } while (0)
 #endif
 
-#ifdef CONFIG_SCHEDSTATS
+#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
 /*
  * Called when a process is dequeued from the active array and given
  * the cpu.  We should note that with the exception of interactive
@@ -155,7 +155,7 @@ static inline void sched_info_dequeued(struct task_struct *t)
  */
 static void sched_info_arrive(struct task_struct *t)
 {
-        unsigned long long now = sched_clock(), delta = 0;
+        unsigned long long now = task_rq(t)->clock, delta = 0;
 
         if (t->sched_info.last_queued)
                 delta = now - t->sched_info.last_queued;
@@ -186,7 +186,7 @@ static inline void sched_info_queued(struct task_struct *t)
 {
         if (unlikely(sched_info_on()))
                 if (!t->sched_info.last_queued)
-                        t->sched_info.last_queued = sched_clock();
+                        t->sched_info.last_queued = task_rq(t)->clock;
 }
 
 /*
@@ -195,7 +195,8 @@ static inline void sched_info_queued(struct task_struct *t)
  */
 static inline void sched_info_depart(struct task_struct *t)
 {
-        unsigned long long delta = sched_clock() - t->sched_info.last_arrival;
+        unsigned long long delta = task_rq(t)->clock -
+                                        t->sched_info.last_arrival;
 
         t->sched_info.cpu_time += delta;
         rq_sched_info_depart(task_rq(t), delta);
@@ -231,5 +232,5 @@ sched_info_switch(struct task_struct *prev, struct task_struct *next)
 #else
 #define sched_info_queued(t)            do { } while (0)
 #define sched_info_switch(t, next)      do { } while (0)
-#endif /* CONFIG_SCHEDSTATS */
+#endif /* CONFIG_SCHEDSTATS || CONFIG_TASK_DELAY_ACCT */