Re: [PATCH v3 2/7] sched: make struct sched_statistics independent of fair sched class

Yafang Shao
2021-08-31T13:26:32Z

On Tue, Aug 31, 2021 at 6:19 PM Peter Zijlstra <peterz@infradead.org> wrote:
>
> On Tue, Aug 24, 2021 at 11:29:41AM +0000, Yafang Shao wrote:
>
> > +#ifdef CONFIG_FAIR_GROUP_SCHED
> > +static inline void
> > +__schedstats_from_sched_entity(struct sched_entity *se,
> > + struct sched_statistics **stats)
> > +{
> > + struct task_group *tg;
> > + struct task_struct *p;
> > + struct cfs_rq *cfs;
> > + int cpu;
> > +
> > + if (entity_is_task(se)) {
> > + p = task_of(se);
> > + *stats = &p->stats;
> > + } else {
> > + cfs = group_cfs_rq(se);
> > + tg = cfs->tg;
> > + cpu = cpu_of(rq_of(cfs));
> > + *stats = tg->stats[cpu];
> > + }
> > +}
> > +
> > +#else
> > +
> > +static inline void
> > +__schedstats_from_sched_entity(struct sched_entity *se,
> > + struct sched_statistics **stats)
> > +{
> > + struct task_struct *p;
> > +
> > + p = task_of(se);
> > + *stats = &p->stats;
> > +}
> > +
> > +#endif
> > +
> > /*
> > * Update the current task's runtime statistics.
> > */
> > @@ -826,6 +861,7 @@ static void update_curr(struct cfs_rq *cfs_rq)
> > {
> > struct sched_entity *curr = cfs_rq->curr;
> > u64 now = rq_clock_task(rq_of(cfs_rq));
> > + struct sched_statistics *stats = NULL;
> > u64 delta_exec;
> >
> > if (unlikely(!curr))
> > @@ -837,8 +873,11 @@ static void update_curr(struct cfs_rq *cfs_rq)
> >
> > curr->exec_start = now;
> >
> > - schedstat_set(curr->statistics.exec_max,
> > - max(delta_exec, curr->statistics.exec_max));
> > + if (schedstat_enabled()) {
> > + __schedstats_from_sched_entity(curr, &stats);
> > + __schedstat_set(stats->exec_max,
> > + max(delta_exec, stats->exec_max));
> > + }
> >
> > curr->sum_exec_runtime += delta_exec;
> > schedstat_add(cfs_rq->exec_clock, delta_exec);
>
>
> That's just really odd style; what's wrong with something like:
>

I will change it.

> static inline struct sched_statistics *
> __schedstats_from_se(struct sched_entity *se)
> {
> ...
> }
>
> if (schedstats_enabled()) {
> struct sched_statistics *stats = __schedstats_from_se(curr);
> __schedstat_set(stats->exec_max, max(stats->exec_max, delta_exec));
> }
>
>

--
Thanks
Yafang