* Daniel Bristot de Oliveira <[email protected]> wrote:
> On 06/22/2017 10:38 AM, Ingo Molnar wrote:
> >
> > * Daniel Bristot de Oliveira <[email protected]> wrote:
> >
> >> void migrate_disable(void)
> >> {
> >> struct task_struct *p = current;
> >> + struct rq *rq;
> >> + struct rq_flags rf;
> >> +
> >>
> >> if (in_atomic() || irqs_disabled()) {
> >> #ifdef CONFIG_SCHED_DEBUG
> >> @@ -7593,10 +7596,21 @@ void migrate_disable(void)
> >> preempt_disable();
> >> preempt_lazy_disable();
> >> pin_current_cpu();
> >> - p->migrate_disable = 1;
> >>
> >> - p->cpus_ptr = cpumask_of(smp_processor_id());
> >> + rq = task_rq_lock(p, &rf);
> >> + if (unlikely((p->sched_class == &rt_sched_class ||
> >> + p->sched_class == &dl_sched_class) &&
> >> + p->nr_cpus_allowed > 1)) {
> >> + if (p->sched_class == &rt_sched_class)
> >> + task_rq(p)->rt.rt_nr_migratory--;
> >> + else
> >> + task_rq(p)->dl.dl_nr_migratory--;
> >> + }
> >> p->nr_cpus_allowed = 1;
> >> + task_rq_unlock(rq, p, &rf);
> >> + p->cpus_ptr = cpumask_of(smp_processor_id());
> >> + p->migrate_disable = 1;
> >> +
> >>
> >> preempt_enable();
> >> }
> >> @@ -7605,6 +7619,9 @@ EXPORT_SYMBOL(migrate_disable);
> >> void migrate_enable(void)
> >> {
> >> struct task_struct *p = current;
> >> + struct rq *rq;
> >> + struct rq_flags rf;
> >> +
> >>
> >> if (in_atomic() || irqs_disabled()) {
> >> #ifdef CONFIG_SCHED_DEBUG
> >> @@ -7628,17 +7645,24 @@ void migrate_enable(void)
> >>
> >> preempt_disable();
> >>
> >> - p->cpus_ptr = &p->cpus_mask;
> >> - p->nr_cpus_allowed = cpumask_weight(&p->cpus_mask);
> >> p->migrate_disable = 0;
> >> + p->cpus_ptr = &p->cpus_mask;
> >>
> >> - if (p->migrate_disable_update) {
> >> - struct rq *rq;
> >> - struct rq_flags rf;
> >> + rq = task_rq_lock(p, &rf);
> >> + p->nr_cpus_allowed = cpumask_weight(&p->cpus_mask);
> >> + if (unlikely((p->sched_class == &rt_sched_class ||
> >> + p->sched_class == &dl_sched_class) &&
> >> + p->nr_cpus_allowed > 1)) {
> >> + if (p->sched_class == &rt_sched_class)
> >> + task_rq(p)->rt.rt_nr_migratory++;
> >> + else
> >> + task_rq(p)->dl.dl_nr_migratory++;
> >> + }
> >> + task_rq_unlock(rq, p, &rf);
> >
> > The fix looks good to me, but AFAICS the repeat pattern introduced here
> > could be
> > factored out into a helper function instead, right?
>
> Like:
>
> static inline int task_in_rt_class(struct task_struct *p)
> {
> return p->sched_class == &rt_sched_class;
> }
>
> static inline int task_in_dl_class(struct task_struct *p)
> {
> return p->sched_class == &dl_sched_class;
> }
>
> ?
So AFAICS it's this block that is used twice:
> >> + rq = task_rq_lock(p, &rf);
> >> + p->nr_cpus_allowed = cpumask_weight(&p->cpus_mask);
> >> + if (unlikely((p->sched_class == &rt_sched_class ||
> >> + p->sched_class == &dl_sched_class) &&
> >> + p->nr_cpus_allowed > 1)) {
> >> + if (p->sched_class == &rt_sched_class)
> >> + task_rq(p)->rt.rt_nr_migratory++;
> >> + else
> >> + task_rq(p)->dl.dl_nr_migratory++;
> >> + }
> >> + task_rq_unlock(rq, p, &rf);
or is there some difference I haven't noticed?
Thanks,
Ingo
