Commit c2a295bf authored by Vincent Guittot's avatar Vincent Guittot Committed by Peter Zijlstra
Browse files

sched/fair: Add new cfs_rq.h_nr_runnable 



With delayed dequeued feature, a sleeping sched_entity remains queued in
the rq until its lag has elapsed. As a result, it stays also visible
in the statistics that are used to balance the system and in particular
the field cfs.h_nr_queued when the sched_entity is associated to a task.

Create a new h_nr_runnable that tracks only queued and runnable tasks.

Signed-off-by: default avatarVincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarDietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lore.kernel.org/r/20241202174606.4074512-5-vincent.guittot@linaro.org
parent 7b8a702d

kernel/sched/debug.c

+1 −0
Original line number Diff line number Diff line
@@ -844,6 +844,7 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) 
	spread = right_vruntime - left_vruntime;

	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "spread", SPLIT_NS(spread));

	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",

kernel/sched/fair.c

+18 −2
Original line number Diff line number Diff line
@@ -5469,6 +5469,7 @@ static void set_delayed(struct sched_entity *se) 
	for_each_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;
@@ -5481,6 +5482,7 @@ static void clear_delayed(struct sched_entity *se) 
	for_each_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;
@@ -5930,7 +5932,7 @@ 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, idle_task_delta, delayed_delta, dequeue = 1;

	long queued_delta, runnable_delta, idle_task_delta, delayed_delta, dequeue = 1;

	long rq_h_nr_queued = rq->cfs.h_nr_queued;



	raw_spin_lock(&cfs_b->lock);
@@ -5962,6 +5964,7 @@ static bool throttle_cfs_rq(struct cfs_rq *cfs_rq) 
	rcu_read_unlock();



	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) {
@@ -5986,6 +5989,7 @@ static bool throttle_cfs_rq(struct cfs_rq *cfs_rq) 
			idle_task_delta = cfs_rq->h_nr_queued;



		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;
@@ -6009,6 +6013,7 @@ static bool throttle_cfs_rq(struct cfs_rq *cfs_rq) 
			idle_task_delta = cfs_rq->h_nr_queued;



		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;

	}
@@ -6036,7 +6041,7 @@ 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, idle_task_delta, delayed_delta;

	long queued_delta, runnable_delta, idle_task_delta, delayed_delta;

	long rq_h_nr_queued = rq->cfs.h_nr_queued;



	se = cfs_rq->tg->se[cpu_of(rq)];
@@ -6071,6 +6076,7 @@ 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) {
@@ -6089,6 +6095,7 @@ void unthrottle_cfs_rq(struct cfs_rq *cfs_rq) 
			idle_task_delta = cfs_rq->h_nr_queued;



		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;
@@ -6107,6 +6114,7 @@ void unthrottle_cfs_rq(struct cfs_rq *cfs_rq) 
			idle_task_delta = cfs_rq->h_nr_queued;



		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;
@@ -7021,6 +7029,8 @@ 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_queued++;

		cfs_rq->idle_h_nr_running += idle_h_nr_running;

		cfs_rq->h_nr_delayed += h_nr_delayed;
@@ -7045,6 +7055,8 @@ 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_queued++;

		cfs_rq->idle_h_nr_running += idle_h_nr_running;

		cfs_rq->h_nr_delayed += h_nr_delayed;
@@ -7135,6 +7147,8 @@ 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_queued -= h_nr_queued;

		cfs_rq->idle_h_nr_running -= idle_h_nr_running;

		cfs_rq->h_nr_delayed -= h_nr_delayed;
@@ -7174,6 +7188,8 @@ 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_queued -= h_nr_queued;

		cfs_rq->idle_h_nr_running -= idle_h_nr_running;

		cfs_rq->h_nr_delayed -= h_nr_delayed;

kernel/sched/sched.h

+1 −0
Original line number Diff line number Diff line
@@ -647,6 +647,7 @@ struct cfs_rq { 
	struct load_weight	load;

	unsigned int		nr_running;

	unsigned int		h_nr_queued;       /* SCHED_{NORMAL,BATCH,IDLE} */

	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;