sched: Discard some old bits

WAKEUP_RUNNING was an experiment, not sure why that ever ended up being
merged...

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

4 files changed, 7 insertions, 19 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index 33c903573132..0170735bdafc 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -2493,7 +2493,6 @@ static void __sched_fork(struct task_struct *p)
         p->se.avg_overlap               = 0;
         p->se.start_runtime             = 0;
         p->se.avg_wakeup                = sysctl_sched_wakeup_granularity;
-        p->se.avg_running               = 0;
 
 #ifdef CONFIG_SCHEDSTATS
         p->se.wait_start                        = 0;
@@ -5379,13 +5378,14 @@ static inline void schedule_debug(struct task_struct *prev)
 #endif
 }
 
-static void put_prev_task(struct rq *rq, struct task_struct *p)
+static void put_prev_task(struct rq *rq, struct task_struct *prev)
 {
-        u64 runtime = p->se.sum_exec_runtime - p->se.prev_sum_exec_runtime;
+        if (prev->state == TASK_RUNNING) {
+                u64 runtime = prev->se.sum_exec_runtime;
 
-        update_avg(&p->se.avg_running, runtime);
+                runtime -= prev->se.prev_sum_exec_runtime;
+                runtime = min_t(u64, runtime, 2*sysctl_sched_migration_cost);
 
-        if (p->state == TASK_RUNNING) {
                 /*
                  * In order to avoid avg_overlap growing stale when we are
                  * indeed overlapping and hence not getting put to sleep, grow
@@ -5395,12 +5395,9 @@ static void put_prev_task(struct rq *rq, struct task_struct *p)
                  * correlates to the amount of cache footprint a task can
                  * build up.
                  */
-                runtime = min_t(u64, runtime, 2*sysctl_sched_migration_cost);
-                update_avg(&p->se.avg_overlap, runtime);
-        } else {
-                update_avg(&p->se.avg_running, 0);
+                update_avg(&prev->se.avg_overlap, runtime);
         }
-        p->sched_class->put_prev_task(rq, p);
+        prev->sched_class->put_prev_task(rq, prev);
 }
 
 /*
diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c
index 6988cf08f705..5fda66615fee 100644
--- a/kernel/sched_debug.c
+++ b/kernel/sched_debug.c
@@ -399,7 +399,6 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
         PN(se.sum_exec_runtime);
         PN(se.avg_overlap);
         PN(se.avg_wakeup);
-        PN(se.avg_running);
 
         nr_switches = p->nvcsw + p->nivcsw;
 
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 76b5792c4198..e9f5daee12c7 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -1689,9 +1689,6 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_
                         pse->avg_overlap < sysctl_sched_migration_cost)
                 goto preempt;
 
-        if (sched_feat(WAKEUP_RUNNING) && pse->avg_running < se->avg_running)
-                goto preempt;
-
         if (!sched_feat(WAKEUP_PREEMPT))
                 return;
 
diff --git a/kernel/sched_features.h b/kernel/sched_features.h
index 0d94083582c7..d5059fd761d9 100644
--- a/kernel/sched_features.h
+++ b/kernel/sched_features.h
@@ -54,11 +54,6 @@ SCHED_FEAT(WAKEUP_SYNC, 0)
 SCHED_FEAT(WAKEUP_OVERLAP, 0)
 
 /*
- * Wakeup preemption towards tasks that run short
- */
-SCHED_FEAT(WAKEUP_RUNNING, 0)
-
-/*
  * Use the SYNC wakeup hint, pipes and the likes use this to indicate
  * the remote end is likely to consume the data we just wrote, and
  * therefore has cache benefit from being placed on the same cpu, see