The following commit has been merged into the sched/core branch of tip: Commit-ID: a480addecc0d89c200ec0b41da62ae8ceddca8d7 Gitweb: https://git.kernel.org/tip/a480addecc0d89c200ec0b41da62ae8ceddca8d7 Author: Josh Don <joshdon@xxxxxxxxxx> AuthorDate: Thu, 19 Aug 2021 18:04:01 -07:00 Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx> CommitterDate: Tue, 05 Oct 2021 15:51:36 +02:00 sched: Account number of SCHED_IDLE entities on each cfs_rq Adds cfs_rq->idle_nr_running, which accounts the number of idle entities directly enqueued on the cfs_rq. Signed-off-by: Josh Don <joshdon@xxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Reviewed-by: Vincent Guittot <vincent.guittot@xxxxxxxxxx> Link: https://lore.kernel.org/r/20210820010403.946838-3-joshdon@xxxxxxxxxx --- kernel/sched/debug.c | 2 ++ kernel/sched/fair.c | 25 ++++++++++++++++++++++++- kernel/sched/sched.h | 1 + 3 files changed, 27 insertions(+), 1 deletion(-) diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index 17a653b..2e5fdd9 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -614,6 +614,8 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) cfs_rq->nr_spread_over); SEQ_printf(m, " .%-30s: %d\n", "nr_running", cfs_rq->nr_running); SEQ_printf(m, " .%-30s: %d\n", "h_nr_running", cfs_rq->h_nr_running); + SEQ_printf(m, " .%-30s: %d\n", "idle_nr_running", + cfs_rq->idle_nr_running); SEQ_printf(m, " .%-30s: %d\n", "idle_h_nr_running", cfs_rq->idle_h_nr_running); SEQ_printf(m, " .%-30s: %ld\n", "load", cfs_rq->load.weight); diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 6cc958e..9c78c16 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2995,6 +2995,8 @@ account_entity_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se) } #endif cfs_rq->nr_running++; + if (se_is_idle(se)) + cfs_rq->idle_nr_running++; } static void @@ -3008,6 +3010,8 @@ account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se) } #endif cfs_rq->nr_running--; + if (se_is_idle(se)) + cfs_rq->idle_nr_running--; } /* @@ -5577,6 +5581,17 @@ static int sched_idle_rq(struct rq *rq) rq->nr_running); } +/* + * Returns true if cfs_rq only has SCHED_IDLE entities enqueued. Note the use + * of idle_nr_running, which does not consider idle descendants of normal + * entities. + */ +static bool sched_idle_cfs_rq(struct cfs_rq *cfs_rq) +{ + return cfs_rq->nr_running && + cfs_rq->nr_running == cfs_rq->idle_nr_running; +} + #ifdef CONFIG_SMP static int sched_idle_cpu(int cpu) { @@ -11575,7 +11590,7 @@ int sched_group_set_idle(struct task_group *tg, long idle) for_each_possible_cpu(i) { struct rq *rq = cpu_rq(i); struct sched_entity *se = tg->se[i]; - struct cfs_rq *grp_cfs_rq = tg->cfs_rq[i]; + struct cfs_rq *parent_cfs_rq, *grp_cfs_rq = tg->cfs_rq[i]; bool was_idle = cfs_rq_is_idle(grp_cfs_rq); long idle_task_delta; struct rq_flags rf; @@ -11586,6 +11601,14 @@ int sched_group_set_idle(struct task_group *tg, long idle) if (WARN_ON_ONCE(was_idle == cfs_rq_is_idle(grp_cfs_rq))) goto next_cpu; + if (se->on_rq) { + parent_cfs_rq = cfs_rq_of(se); + if (cfs_rq_is_idle(grp_cfs_rq)) + parent_cfs_rq->idle_nr_running++; + else + parent_cfs_rq->idle_nr_running--; + } + idle_task_delta = grp_cfs_rq->h_nr_running - grp_cfs_rq->idle_h_nr_running; if (!cfs_rq_is_idle(grp_cfs_rq)) diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 1fec313..f2965b5 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -530,6 +530,7 @@ struct cfs_rq { struct load_weight load; unsigned int nr_running; unsigned int h_nr_running; /* SCHED_{NORMAL,BATCH,IDLE} */ + unsigned int idle_nr_running; /* SCHED_IDLE */ unsigned int idle_h_nr_running; /* SCHED_IDLE */ u64 exec_clock;