From 01d36d0ac390895e719d0dd8ab91ebbbf506d28e Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Wed, 4 Nov 2015 18:17:10 +0100 Subject: [PATCH] sched: Account rr tasks In order to evaluate the scheduler tick dependency without probing context switches, we need to know how much SCHED_RR and SCHED_FIFO tasks are enqueued as those policies don't have the same preemption requirements. To prepare for that, let's account SCHED_RR tasks, we'll be able to deduce SCHED_FIFO tasks as well from it and the total RT tasks in the runqueue. Reviewed-by: Chris Metcalf Cc: Christoph Lameter Cc: Chris Metcalf Cc: Ingo Molnar Cc: Luiz Capitulino Cc: Peter Zijlstra Cc: Rik van Riel Cc: Thomas Gleixner Cc: Viresh Kumar Signed-off-by: Frederic Weisbecker --- kernel/sched/rt.c | 16 ++++++++++++++++ kernel/sched/sched.h | 1 + 2 files changed, 17 insertions(+) diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 8ec86abe0ea1..3f1fcffbb18f 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -1141,6 +1141,20 @@ unsigned int rt_se_nr_running(struct sched_rt_entity *rt_se) return 1; } +static inline +unsigned int rt_se_rr_nr_running(struct sched_rt_entity *rt_se) +{ + struct rt_rq *group_rq = group_rt_rq(rt_se); + struct task_struct *tsk; + + if (group_rq) + return group_rq->rr_nr_running; + + tsk = rt_task_of(rt_se); + + return (tsk->policy == SCHED_RR) ? 1 : 0; +} + static inline void inc_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) { @@ -1148,6 +1162,7 @@ void inc_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) WARN_ON(!rt_prio(prio)); rt_rq->rt_nr_running += rt_se_nr_running(rt_se); + rt_rq->rr_nr_running += rt_se_rr_nr_running(rt_se); inc_rt_prio(rt_rq, prio); inc_rt_migration(rt_se, rt_rq); @@ -1160,6 +1175,7 @@ void dec_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) WARN_ON(!rt_prio(rt_se_prio(rt_se))); WARN_ON(!rt_rq->rt_nr_running); rt_rq->rt_nr_running -= rt_se_nr_running(rt_se); + rt_rq->rr_nr_running -= rt_se_rr_nr_running(rt_se); dec_rt_prio(rt_rq, rt_se_prio(rt_se)); dec_rt_migration(rt_se, rt_rq); diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 10f16374df7f..f0abfce14044 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -450,6 +450,7 @@ static inline int rt_bandwidth_enabled(void) struct rt_rq { struct rt_prio_array active; unsigned int rt_nr_running; + unsigned int rr_nr_running; #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED struct { int curr; /* highest queued rt task prio */ -- 2.45.2