[tip: sched/core] sched/fair: Removed unsued cfs_rq.h_nr_delayed

["tip-bot2 for Vincent Guittot" <tip-bot2@linutronix.de>]

The following commit has been merged into the sched/core branch of tip:

Commit-ID:     9216582b0bfb17889eebcf96fb41cd67a3d71133
Gitweb:        https://git.kernel.org/tip/9216582b0bfb17889eebcf96fb41cd67a3d71133
Author:        Vincent Guittot <vincent.guittot@linaro.org>
AuthorDate:    Mon, 02 Dec 2024 18:46:01 +01:00
Committer:     Peter Zijlstra <peterz@infradead.org>
CommitterDate: Mon, 09 Dec 2024 11:48:11 +01:00

sched/fair: Removed unsued cfs_rq.h_nr_delayed

h_nr_delayed is not used anymore. We now have:
 - h_nr_runnable which tracks tasks ready to run
 - h_nr_queued which tracks enqueued tasks either ready to run or
   delayed dequeue

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lore.kernel.org/r/20241202174606.4074512-7-vincent.guittot@linaro.org
---
 kernel/sched/debug.c |  1 -
 kernel/sched/fair.c  | 40 ++++++++++++----------------------------
 kernel/sched/sched.h |  1 -
 3 files changed, 12 insertions(+), 30 deletions(-)

diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index fd711cc..56be365 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -846,7 +846,6 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 	SEQ_printf(m, "  .%-30s: %d\n", "nr_running", cfs_rq->nr_running);
 	SEQ_printf(m, "  .%-30s: %d\n", "h_nr_runnable", cfs_rq->h_nr_runnable);
 	SEQ_printf(m, "  .%-30s: %d\n", "h_nr_queued", cfs_rq->h_nr_queued);
-	SEQ_printf(m, "  .%-30s: %d\n", "h_nr_delayed", cfs_rq->h_nr_delayed);
 	SEQ_printf(m, "  .%-30s: %d\n", "idle_nr_running",
 			cfs_rq->idle_nr_running);
 	SEQ_printf(m, "  .%-30s: %d\n", "idle_h_nr_running",
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 3a8bdfb..5c2f049 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -5470,7 +5470,6 @@ static void set_delayed(struct sched_entity *se)
 		struct cfs_rq *cfs_rq = cfs_rq_of(se);
 
 		cfs_rq->h_nr_runnable--;
-		cfs_rq->h_nr_delayed++;
 		if (cfs_rq_throttled(cfs_rq))
 			break;
 	}
@@ -5483,7 +5482,6 @@ static void clear_delayed(struct sched_entity *se)
 		struct cfs_rq *cfs_rq = cfs_rq_of(se);
 
 		cfs_rq->h_nr_runnable++;
-		cfs_rq->h_nr_delayed--;
 		if (cfs_rq_throttled(cfs_rq))
 			break;
 	}
@@ -5932,7 +5930,7 @@ static bool throttle_cfs_rq(struct cfs_rq *cfs_rq)
 	struct rq *rq = rq_of(cfs_rq);
 	struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
 	struct sched_entity *se;
-	long queued_delta, runnable_delta, idle_task_delta, delayed_delta, dequeue = 1;
+	long queued_delta, runnable_delta, idle_task_delta, dequeue = 1;
 	long rq_h_nr_queued = rq->cfs.h_nr_queued;
 
 	raw_spin_lock(&cfs_b->lock);
@@ -5966,7 +5964,6 @@ static bool throttle_cfs_rq(struct cfs_rq *cfs_rq)
 	queued_delta = cfs_rq->h_nr_queued;
 	runnable_delta = cfs_rq->h_nr_runnable;
 	idle_task_delta = cfs_rq->idle_h_nr_running;
-	delayed_delta = cfs_rq->h_nr_delayed;
 	for_each_sched_entity(se) {
 		struct cfs_rq *qcfs_rq = cfs_rq_of(se);
 		int flags;
@@ -5991,7 +5988,6 @@ static bool throttle_cfs_rq(struct cfs_rq *cfs_rq)
 		qcfs_rq->h_nr_queued -= queued_delta;
 		qcfs_rq->h_nr_runnable -= runnable_delta;
 		qcfs_rq->idle_h_nr_running -= idle_task_delta;
-		qcfs_rq->h_nr_delayed -= delayed_delta;
 
 		if (qcfs_rq->load.weight) {
 			/* Avoid re-evaluating load for this entity: */
@@ -6015,7 +6011,6 @@ static bool throttle_cfs_rq(struct cfs_rq *cfs_rq)
 		qcfs_rq->h_nr_queued -= queued_delta;
 		qcfs_rq->h_nr_runnable -= runnable_delta;
 		qcfs_rq->idle_h_nr_running -= idle_task_delta;
-		qcfs_rq->h_nr_delayed -= delayed_delta;
 	}
 
 	/* At this point se is NULL and we are at root level*/
@@ -6041,7 +6036,7 @@ void unthrottle_cfs_rq(struct cfs_rq *cfs_rq)
 	struct rq *rq = rq_of(cfs_rq);
 	struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
 	struct sched_entity *se;
-	long queued_delta, runnable_delta, idle_task_delta, delayed_delta;
+	long queued_delta, runnable_delta, idle_task_delta;
 	long rq_h_nr_queued = rq->cfs.h_nr_queued;
 
 	se = cfs_rq->tg->se[cpu_of(rq)];
@@ -6078,7 +6073,6 @@ void unthrottle_cfs_rq(struct cfs_rq *cfs_rq)
 	queued_delta = cfs_rq->h_nr_queued;
 	runnable_delta = cfs_rq->h_nr_runnable;
 	idle_task_delta = cfs_rq->idle_h_nr_running;
-	delayed_delta = cfs_rq->h_nr_delayed;
 	for_each_sched_entity(se) {
 		struct cfs_rq *qcfs_rq = cfs_rq_of(se);
 
@@ -6097,7 +6091,6 @@ void unthrottle_cfs_rq(struct cfs_rq *cfs_rq)
 		qcfs_rq->h_nr_queued += queued_delta;
 		qcfs_rq->h_nr_runnable += runnable_delta;
 		qcfs_rq->idle_h_nr_running += idle_task_delta;
-		qcfs_rq->h_nr_delayed += delayed_delta;
 
 		/* end evaluation on encountering a throttled cfs_rq */
 		if (cfs_rq_throttled(qcfs_rq))
@@ -6116,7 +6109,6 @@ void unthrottle_cfs_rq(struct cfs_rq *cfs_rq)
 		qcfs_rq->h_nr_queued += queued_delta;
 		qcfs_rq->h_nr_runnable += runnable_delta;
 		qcfs_rq->idle_h_nr_running += idle_task_delta;
-		qcfs_rq->h_nr_delayed += delayed_delta;
 
 		/* end evaluation on encountering a throttled cfs_rq */
 		if (cfs_rq_throttled(qcfs_rq))
@@ -6979,7 +6971,7 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags)
 	struct cfs_rq *cfs_rq;
 	struct sched_entity *se = &p->se;
 	int idle_h_nr_running = task_has_idle_policy(p);
-	int h_nr_delayed = 0;
+	int h_nr_runnable = 1;
 	int task_new = !(flags & ENQUEUE_WAKEUP);
 	int rq_h_nr_queued = rq->cfs.h_nr_queued;
 	u64 slice = 0;
@@ -7006,8 +6998,8 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags)
 	if (p->in_iowait)
 		cpufreq_update_util(rq, SCHED_CPUFREQ_IOWAIT);
 
-	if (task_new)
-		h_nr_delayed = !!se->sched_delayed;
+	if (task_new && se->sched_delayed)
+		h_nr_runnable = 0;
 
 	for_each_sched_entity(se) {
 		if (se->on_rq) {
@@ -7029,11 +7021,9 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags)
 		enqueue_entity(cfs_rq, se, flags);
 		slice = cfs_rq_min_slice(cfs_rq);
 
-		if (!h_nr_delayed)
-			cfs_rq->h_nr_runnable++;
+		cfs_rq->h_nr_runnable += h_nr_runnable;
 		cfs_rq->h_nr_queued++;
 		cfs_rq->idle_h_nr_running += idle_h_nr_running;
-		cfs_rq->h_nr_delayed += h_nr_delayed;
 
 		if (cfs_rq_is_idle(cfs_rq))
 			idle_h_nr_running = 1;
@@ -7055,11 +7045,9 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags)
 		se->slice = slice;
 		slice = cfs_rq_min_slice(cfs_rq);
 
-		if (!h_nr_delayed)
-			cfs_rq->h_nr_runnable++;
+		cfs_rq->h_nr_runnable += h_nr_runnable;
 		cfs_rq->h_nr_queued++;
 		cfs_rq->idle_h_nr_running += idle_h_nr_running;
-		cfs_rq->h_nr_delayed += h_nr_delayed;
 
 		if (cfs_rq_is_idle(cfs_rq))
 			idle_h_nr_running = 1;
@@ -7122,7 +7110,7 @@ static int dequeue_entities(struct rq *rq, struct sched_entity *se, int flags)
 	struct task_struct *p = NULL;
 	int idle_h_nr_running = 0;
 	int h_nr_queued = 0;
-	int h_nr_delayed = 0;
+	int h_nr_runnable = 0;
 	struct cfs_rq *cfs_rq;
 	u64 slice = 0;
 
@@ -7130,8 +7118,8 @@ static int dequeue_entities(struct rq *rq, struct sched_entity *se, int flags)
 		p = task_of(se);
 		h_nr_queued = 1;
 		idle_h_nr_running = task_has_idle_policy(p);
-		if (!task_sleep && !task_delayed)
-			h_nr_delayed = !!se->sched_delayed;
+		if (task_sleep || task_delayed || !se->sched_delayed)
+			h_nr_runnable = 1;
 	} else {
 		cfs_rq = group_cfs_rq(se);
 		slice = cfs_rq_min_slice(cfs_rq);
@@ -7147,11 +7135,9 @@ static int dequeue_entities(struct rq *rq, struct sched_entity *se, int flags)
 			break;
 		}
 
-		if (!h_nr_delayed)
-			cfs_rq->h_nr_runnable -= h_nr_queued;
+		cfs_rq->h_nr_runnable -= h_nr_runnable;
 		cfs_rq->h_nr_queued -= h_nr_queued;
 		cfs_rq->idle_h_nr_running -= idle_h_nr_running;
-		cfs_rq->h_nr_delayed -= h_nr_delayed;
 
 		if (cfs_rq_is_idle(cfs_rq))
 			idle_h_nr_running = h_nr_queued;
@@ -7188,11 +7174,9 @@ static int dequeue_entities(struct rq *rq, struct sched_entity *se, int flags)
 		se->slice = slice;
 		slice = cfs_rq_min_slice(cfs_rq);
 
-		if (!h_nr_delayed)
-			cfs_rq->h_nr_runnable -= h_nr_queued;
+		cfs_rq->h_nr_runnable -= h_nr_runnable;
 		cfs_rq->h_nr_queued -= h_nr_queued;
 		cfs_rq->idle_h_nr_running -= idle_h_nr_running;
-		cfs_rq->h_nr_delayed -= h_nr_delayed;
 
 		if (cfs_rq_is_idle(cfs_rq))
 			idle_h_nr_running = h_nr_queued;
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 4374c66..d3ce5e9 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -650,7 +650,6 @@ struct cfs_rq {
 	unsigned int		h_nr_runnable;     /* SCHED_{NORMAL,BATCH,IDLE} */
 	unsigned int		idle_nr_running;   /* SCHED_IDLE */
 	unsigned int		idle_h_nr_running; /* SCHED_IDLE */
-	unsigned int		h_nr_delayed;
 
 	s64			avg_vruntime;
 	u64			avg_load;