From 9f68395333ad7f5bfe2f83473fed363d4229f11c Mon Sep 17 00:00:00 2001 From: Vincent Guittot Date: Mon, 24 Feb 2020 09:52:18 +0000 Subject: sched/pelt: Add a new runnable average signal Now that runnable_load_avg has been removed, we can replace it by a new signal that will highlight the runnable pressure on a cfs_rq. This signal track the waiting time of tasks on rq and can help to better define the state of rqs. At now, only util_avg is used to define the state of a rq: A rq with more that around 80% of utilization and more than 1 tasks is considered as overloaded. But the util_avg signal of a rq can become temporaly low after that a task migrated onto another rq which can bias the classification of the rq. When tasks compete for the same rq, their runnable average signal will be higher than util_avg as it will include the waiting time and we can use this signal to better classify cfs_rqs. The new runnable_avg will track the runnable time of a task which simply adds the waiting time to the running time. The runnable _avg of cfs_rq will be the /Sum of se's runnable_avg and the runnable_avg of group entity will follow the one of the rq similarly to util_avg. Signed-off-by: Vincent Guittot Signed-off-by: Mel Gorman Signed-off-by: Ingo Molnar Reviewed-by: "Dietmar Eggemann " Acked-by: Peter Zijlstra Cc: Juri Lelli Cc: Valentin Schneider Cc: Phil Auld Cc: Hillf Danton Link: https://lore.kernel.org/r/20200224095223.13361-9-mgorman@techsingularity.net --- kernel/sched/debug.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'kernel/sched/debug.c') diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index cfecaad387c0..8331bc04aea2 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -405,6 +405,7 @@ static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group #ifdef CONFIG_SMP P(se->avg.load_avg); P(se->avg.util_avg); + P(se->avg.runnable_avg); #endif #undef PN_SCHEDSTAT @@ -524,6 +525,8 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) #ifdef CONFIG_SMP SEQ_printf(m, " .%-30s: %lu\n", "load_avg", cfs_rq->avg.load_avg); + SEQ_printf(m, " .%-30s: %lu\n", "runnable_avg", + cfs_rq->avg.runnable_avg); SEQ_printf(m, " .%-30s: %lu\n", "util_avg", cfs_rq->avg.util_avg); SEQ_printf(m, " .%-30s: %u\n", "util_est_enqueued", @@ -532,8 +535,8 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) cfs_rq->removed.load_avg); SEQ_printf(m, " .%-30s: %ld\n", "removed.util_avg", cfs_rq->removed.util_avg); - SEQ_printf(m, " .%-30s: %ld\n", "removed.runnable_sum", - cfs_rq->removed.runnable_sum); + SEQ_printf(m, " .%-30s: %ld\n", "removed.runnable_avg", + cfs_rq->removed.runnable_avg); #ifdef CONFIG_FAIR_GROUP_SCHED SEQ_printf(m, " .%-30s: %lu\n", "tg_load_avg_contrib", cfs_rq->tg_load_avg_contrib); @@ -944,8 +947,10 @@ void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns, P(se.load.weight); #ifdef CONFIG_SMP P(se.avg.load_sum); + P(se.avg.runnable_sum); P(se.avg.util_sum); P(se.avg.load_avg); + P(se.avg.runnable_avg); P(se.avg.util_avg); P(se.avg.last_update_time); P(se.avg.util_est.ewma); -- cgit v1.2.3-70-g09d2