Re: [PATCH v3 3/7] sched: make schedstats helpers independent of fair sched class

From: Yafang Shao
Date: Tue Aug 31 2021 - 09:28:23 EST


On Tue, Aug 31, 2021 at 7:08 PM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
>
> On Tue, Aug 24, 2021 at 11:29:42AM +0000, Yafang Shao wrote:
> > diff --git a/kernel/sched/stats.c b/kernel/sched/stats.c
> > index 3f93fc3b5648..b2542f4d3192 100644
> > --- a/kernel/sched/stats.c
> > +++ b/kernel/sched/stats.c
> > @@ -4,6 +4,109 @@
> > */
> > #include "sched.h"
> >
> > +void __update_stats_wait_start(struct rq *rq, struct task_struct *p,
> > + struct sched_statistics *stats)
> > +{
> > +u64 wait_start, prev_wait_start;
>
> indent fail...
>

Sorry about that.
It is strange that my checkpatch.pl didn't find this issue...

> > +
> > + wait_start = rq_clock(rq);
> > + prev_wait_start = schedstat_val(stats->wait_start);
> > +
> > + if (p && likely(wait_start > prev_wait_start))
> > + wait_start -= prev_wait_start;
> > +
> > + __schedstat_set(stats->wait_start, wait_start);
> > +}
>
> > diff --git a/kernel/sched/stats.h b/kernel/sched/stats.h
> > index e6905e369c5d..9ecd81b91f26 100644
> > --- a/kernel/sched/stats.h
> > +++ b/kernel/sched/stats.h
>
> > @@ -40,6 +42,33 @@ rq_sched_info_dequeue(struct rq *rq, unsigned long long delta)
> > #define schedstat_val(var) (var)
> > #define schedstat_val_or_zero(var) ((schedstat_enabled()) ? (var) : 0)
> >
> > +void __update_stats_wait_start(struct rq *rq, struct task_struct *p,
> > + struct sched_statistics *stats);
> > +
> > +void __update_stats_wait_end(struct rq *rq, struct task_struct *p,
> > + struct sched_statistics *stats);
> > +void __update_stats_enqueue_sleeper(struct rq *rq, struct task_struct *p,
> > + struct sched_statistics *stats);
> > +
> > +static inline void
> > +check_schedstat_required(void)
> > +{
> > + if (schedstat_enabled())
> > + return;
> > +
> > + /* Force schedstat enabled if a dependent tracepoint is active */
> > + if (trace_sched_stat_wait_enabled() ||
> > + trace_sched_stat_sleep_enabled() ||
> > + trace_sched_stat_iowait_enabled() ||
> > + trace_sched_stat_blocked_enabled() ||
> > + trace_sched_stat_runtime_enabled()) {
> > + printk_deferred_once("Scheduler tracepoints stat_sleep, stat_iowait, "
> > + "stat_blocked and stat_runtime require the "
> > + "kernel parameter schedstats=enable or "
> > + "kernel.sched_schedstats=1\n");
> > + }
> > +}
>
> If you're moving this, you might as well reflow it to not have broken
> indentation.

Sure.


--
Thanks
Yafang