From 68767a0ae428801649d510d9a65bb71feed44dd1 Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Sat, 25 Jun 2005 14:57:20 -0700 Subject: [PATCH] [PATCH] sched: schedstats update for balance on fork Add SCHEDSTAT statistics for sched-balance-fork. Signed-off-by: Nick Piggin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sched.h | 10 +++++-- kernel/sched.c | 63 ++++++++++++++++++++++++------------------- 2 files changed, 44 insertions(+), 29 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 613491d3a875..36a10781c3f3 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -517,10 +517,16 @@ struct sched_domain { unsigned long alb_failed; unsigned long alb_pushed; - /* sched_balance_exec() stats */ - unsigned long sbe_attempts; + /* SD_BALANCE_EXEC stats */ + unsigned long sbe_cnt; + unsigned long sbe_balanced; unsigned long sbe_pushed; + /* SD_BALANCE_FORK stats */ + unsigned long sbf_cnt; + unsigned long sbf_balanced; + unsigned long sbf_pushed; + /* try_to_wake_up() stats */ unsigned long ttwu_wake_remote; unsigned long ttwu_move_affine; diff --git a/kernel/sched.c b/kernel/sched.c index 7ecc237e2aab..2711130cd973 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -309,7 +309,7 @@ static inline void task_rq_unlock(runqueue_t *rq, unsigned long *flags) * bump this up when changing the output format or the meaning of an existing * format, so that tools can adapt (or abort) */ -#define SCHEDSTAT_VERSION 11 +#define SCHEDSTAT_VERSION 12 static int show_schedstat(struct seq_file *seq, void *v) { @@ -356,9 +356,10 @@ static int show_schedstat(struct seq_file *seq, void *v) sd->lb_nobusyq[itype], sd->lb_nobusyg[itype]); } - seq_printf(seq, " %lu %lu %lu %lu %lu %lu %lu %lu\n", + seq_printf(seq, " %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu\n", sd->alb_cnt, sd->alb_failed, sd->alb_pushed, - sd->sbe_pushed, sd->sbe_attempts, + sd->sbe_cnt, sd->sbe_balanced, sd->sbe_pushed, + sd->sbf_cnt, sd->sbf_balanced, sd->sbf_pushed, sd->ttwu_wake_remote, sd->ttwu_move_affine, sd->ttwu_move_balance); } #endif @@ -1264,24 +1265,34 @@ void fastcall wake_up_new_task(task_t * p, unsigned long clone_flags) sd = tmp; if (sd) { + int new_cpu; struct sched_group *group; + schedstat_inc(sd, sbf_cnt); cpu = task_cpu(p); group = find_idlest_group(sd, p, cpu); - if (group) { - int new_cpu; - new_cpu = find_idlest_cpu(group, cpu); - if (new_cpu != -1 && new_cpu != cpu && - cpu_isset(new_cpu, p->cpus_allowed)) { - set_task_cpu(p, new_cpu); - task_rq_unlock(rq, &flags); - rq = task_rq_lock(p, &flags); - cpu = task_cpu(p); - } + if (!group) { + schedstat_inc(sd, sbf_balanced); + goto no_forkbalance; + } + + new_cpu = find_idlest_cpu(group, cpu); + if (new_cpu == -1 || new_cpu == cpu) { + schedstat_inc(sd, sbf_balanced); + goto no_forkbalance; + } + + if (cpu_isset(new_cpu, p->cpus_allowed)) { + schedstat_inc(sd, sbf_pushed); + set_task_cpu(p, new_cpu); + task_rq_unlock(rq, &flags); + rq = task_rq_lock(p, &flags); + cpu = task_cpu(p); } } -#endif +no_forkbalance: +#endif /* * We decrease the sleep average of forking parents * and children as well, to keep max-interactive tasks @@ -1618,30 +1629,28 @@ void sched_exec(void) struct sched_domain *tmp, *sd = NULL; int new_cpu, this_cpu = get_cpu(); - /* Prefer the current CPU if there's only this task running */ - if (this_rq()->nr_running <= 1) - goto out; - for_each_domain(this_cpu, tmp) if (tmp->flags & SD_BALANCE_EXEC) sd = tmp; if (sd) { struct sched_group *group; - schedstat_inc(sd, sbe_attempts); + schedstat_inc(sd, sbe_cnt); group = find_idlest_group(sd, current, this_cpu); - if (!group) + if (!group) { + schedstat_inc(sd, sbe_balanced); goto out; + } new_cpu = find_idlest_cpu(group, this_cpu); - if (new_cpu == -1) + if (new_cpu == -1 || new_cpu == this_cpu) { + schedstat_inc(sd, sbe_balanced); goto out; - - if (new_cpu != this_cpu) { - schedstat_inc(sd, sbe_pushed); - put_cpu(); - sched_migrate_task(current, new_cpu); - return; } + + schedstat_inc(sd, sbe_pushed); + put_cpu(); + sched_migrate_task(current, new_cpu); + return; } out: put_cpu(); -- 2.20.1