sched/{rt,deadline}: Fix set_next_task vs pick_next_task

Because pick_next_task() implies set_curr_task() and some of the
details haven't mattered too much, some of what _should_ be in
set_curr_task() ended up in pick_next_task, correct this.

This prepares the way for a pick_next_task() variant that does not
affect the current state; allowing remote picking.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Aaron Lu <aaron.lwe@gmail.com>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: mingo@kernel.org
Cc: Phil Auld <pauld@redhat.com>
Cc: Julien Desfossez <jdesfossez@digitalocean.com>
Cc: Nishanth Aravamudan <naravamudan@digitalocean.com>
Link: https://lkml.kernel.org/r/38c61d5240553e043c27c5e00b9dd0d184dd6081.1559129225.git.vpillai@digitalocean.com

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 039dde2..2dc2784 100644 (file)
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -1727,12 +1727,20 @@ static void start_hrtick_dl(struct rq *rq, struct task_struct *p)
 }
 #endif
 
-static inline void set_next_task(struct rq *rq, struct task_struct *p)
+static void set_next_task_dl(struct rq *rq, struct task_struct *p)
 {
        p->se.exec_start = rq_clock_task(rq);
 
        /* You can't push away the running task */
        dequeue_pushable_dl_task(rq, p);
+
+       if (hrtick_enabled(rq))
+               start_hrtick_dl(rq, p);
+
+       if (rq->curr->sched_class != &dl_sched_class)
+               update_dl_rq_load_avg(rq_clock_pelt(rq), rq, 0);
+
+       deadline_queue_push_tasks(rq);
 }
 
 static struct sched_dl_entity *pick_next_dl_entity(struct rq *rq,
@@ -1791,15 +1799,7 @@ pick_next_task_dl(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
 
        p = dl_task_of(dl_se);
 
-       set_next_task(rq, p);
-
-       if (hrtick_enabled(rq))
-               start_hrtick_dl(rq, p);
-
-       deadline_queue_push_tasks(rq);
-
-       if (rq->curr->sched_class != &dl_sched_class)
-               update_dl_rq_load_avg(rq_clock_pelt(rq), rq, 0);
+       set_next_task_dl(rq, p);
 
        return p;
 }
@@ -1846,7 +1846,7 @@ static void task_fork_dl(struct task_struct *p)
 
 static void set_curr_task_dl(struct rq *rq)
 {
-       set_next_task(rq, rq->curr);
+       set_next_task_dl(rq, rq->curr);
 }
 
 #ifdef CONFIG_SMP

diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index a532558..40bb710 100644 (file)
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -1498,12 +1498,22 @@ static void check_preempt_curr_rt(struct rq *rq, struct task_struct *p, int flag
 #endif
 }
 
-static inline void set_next_task(struct rq *rq, struct task_struct *p)
+static inline void set_next_task_rt(struct rq *rq, struct task_struct *p)
 {
        p->se.exec_start = rq_clock_task(rq);
 
        /* The running task is never eligible for pushing */
        dequeue_pushable_task(rq, p);
+
+       /*
+        * If prev task was rt, put_prev_task() has already updated the
+        * utilization. We only care of the case where we start to schedule a
+        * rt task
+        */
+       if (rq->curr->sched_class != &rt_sched_class)
+               update_rt_rq_load_avg(rq_clock_pelt(rq), rq, 0);
+
+       rt_queue_push_tasks(rq);
 }
 
 static struct sched_rt_entity *pick_next_rt_entity(struct rq *rq,
@@ -1577,17 +1587,7 @@ pick_next_task_rt(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
 
        p = _pick_next_task_rt(rq);
 
-       set_next_task(rq, p);
-
-       rt_queue_push_tasks(rq);
-
-       /*
-        * If prev task was rt, put_prev_task() has already updated the
-        * utilization. We only care of the case where we start to schedule a
-        * rt task
-        */
-       if (rq->curr->sched_class != &rt_sched_class)
-               update_rt_rq_load_avg(rq_clock_pelt(rq), rq, 0);
+       set_next_task_rt(rq, p);
 
        return p;
 }
@@ -2356,7 +2356,7 @@ static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
 
 static void set_curr_task_rt(struct rq *rq)
 {
-       set_next_task(rq, rq->curr);
+       set_next_task_rt(rq, rq->curr);
 }
 
 static unsigned int get_rr_interval_rt(struct rq *rq, struct task_struct *task)