Hi Dietmar, Sorry for the late answer
On 31 May 2018 at 18:54, Dietmar Eggemann <[email protected]> wrote: > On 05/30/2018 08:45 PM, Vincent Guittot wrote: >> Hi Dietmar, >> >> On 30 May 2018 at 17:55, Dietmar Eggemann <[email protected]> wrote: >>> On 05/25/2018 03:12 PM, Vincent Guittot wrote: > > [...] > >>>> + */ >>>> + ret = ___update_load_sum(rq->clock - running, rq->cpu, >>>> &rq->avg_irq, >>>> + 0, >>>> + 0, >>>> + 0); >>>> + ret += ___update_load_sum(rq->clock, rq->cpu, &rq->avg_irq, >>>> + 1, >>>> + 1, >>>> + 1); > > Can you not change the function parameter list to the usual > (u64 now, struct rq *rq, int running)? > > Something like this (only compile and boot tested): To be honest, I prefer to keep the specific sequence above in a dedicated function instead of adding it in core code. Furthermore, we end up calling call twice ___update_load_avg instead of only once. This will set an intermediate and incorrect value in util_avg and this value can be read in the meantime Vincent > > -- >8 -- > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index 9894bc7af37e..26ffd585cab8 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -177,8 +177,22 @@ static void update_rq_clock_task(struct rq *rq, s64 > delta) > rq->clock_task += delta; > > #if defined(CONFIG_IRQ_TIME_ACCOUNTING) || > defined(CONFIG_PARAVIRT_TIME_ACCOUNTING) > - if ((irq_delta + steal) && sched_feat(NONTASK_CAPACITY)) > - update_irq_load_avg(rq, irq_delta + steal); > + if ((irq_delta + steal) && sched_feat(NONTASK_CAPACITY)) { > + /* > + * We know the time that has been used by interrupt since last > + * update but we don't when. Let be pessimistic and assume > that > + * interrupt has happened just before the update. This is not > + * so far from reality because interrupt will most probably > + * wake up task and trig an update of rq clock during which > the > + * metric si updated. > + * We start to decay with normal context time and then we add > + * the interrupt context time. > + * We can safely remove running from rq->clock because > + * rq->clock += delta with delta >= running > + */ > + update_irq_load_avg(rq_clock(rq) - (irq_delta + steal), rq, > 0); > + update_irq_load_avg(rq_clock(rq), rq, 1); > + } > #endif > } > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index 1bb3379c4b71..a245f853c271 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -7363,7 +7363,7 @@ static void update_blocked_averages(int cpu) > } > update_rt_rq_load_avg(rq_clock_task(rq), rq, 0); > update_dl_rq_load_avg(rq_clock_task(rq), rq, 0); > - update_irq_load_avg(rq, 0); > + update_irq_load_avg(rq_clock(rq), rq, 0); > /* Don't need periodic decay once load/util_avg are null */ > if (others_rqs_have_blocked(rq)) > done = false; > @@ -7434,7 +7434,7 @@ static inline void update_blocked_averages(int cpu) > update_cfs_rq_load_avg(cfs_rq_clock_task(cfs_rq), cfs_rq); > update_rt_rq_load_avg(rq_clock_task(rq), rq, 0); > update_dl_rq_load_avg(rq_clock_task(rq), rq, 0); > - update_irq_load_avg(rq, 0); > + update_irq_load_avg(rq_clock(rq), rq, 0); > #ifdef CONFIG_NO_HZ_COMMON > rq->last_blocked_load_update_tick = jiffies; > if (!cfs_rq_has_blocked(cfs_rq) && !others_rqs_have_blocked(rq)) > diff --git a/kernel/sched/pelt.c b/kernel/sched/pelt.c > index d2e4f2186b13..ae01bb18e28c 100644 > --- a/kernel/sched/pelt.c > +++ b/kernel/sched/pelt.c > @@ -365,31 +365,15 @@ int update_dl_rq_load_avg(u64 now, struct rq *rq, int > running) > * > */ > > -int update_irq_load_avg(struct rq *rq, u64 running) > +int update_irq_load_avg(u64 now, struct rq *rq, int running) > { > - int ret = 0; > - /* > - * We know the time that has been used by interrupt since last update > - * but we don't when. Let be pessimistic and assume that interrupt has > - * happened just before the update. This is not so far from reality > - * because interrupt will most probably wake up task and trig an > update > - * of rq clock during which the metric si updated. > - * We start to decay with normal context time and then we add the > - * interrupt context time. > - * We can safely remove running from rq->clock because > - * rq->clock += delta with delta >= running > - */ > - ret = ___update_load_sum(rq->clock - running, rq->cpu, &rq->avg_irq, > - 0, > - 0, > - 0); > - ret += ___update_load_sum(rq->clock, rq->cpu, &rq->avg_irq, > - 1, > - 1, > - 1); > - > - if (ret) > + if (___update_load_sum(now, rq->cpu, &rq->avg_irq, > + running, > + running, > + running)) { > ___update_load_avg(&rq->avg_irq, 1, 1); > + return 1; > + } > > - return ret; > + return 0; > } > diff --git a/kernel/sched/pelt.h b/kernel/sched/pelt.h > index 0ce9a5a5877a..ebc57301a9a8 100644 > --- a/kernel/sched/pelt.h > +++ b/kernel/sched/pelt.h > @@ -5,7 +5,7 @@ int __update_load_avg_se(u64 now, int cpu, struct cfs_rq > *cfs_rq, struct sched_e > int __update_load_avg_cfs_rq(u64 now, int cpu, struct cfs_rq *cfs_rq); > int update_rt_rq_load_avg(u64 now, struct rq *rq, int running); > int update_dl_rq_load_avg(u64 now, struct rq *rq, int running); > -int update_irq_load_avg(struct rq *rq, u64 running); > +int update_irq_load_avg(u64 now, struct rq *rq, int running); > > /* > * When a task is dequeued, its estimated utilization should not be update if > >
