diff options
Diffstat (limited to 'kernel/sched/core.c')
| -rw-r--r-- | kernel/sched/core.c | 37 |
1 files changed, 16 insertions, 21 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 047fbe8ef298..04b62c16fa8c 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5638,15 +5638,12 @@ unsigned long long nr_context_switches(void) } /* - * Consumers of these two interfaces, like for example the cpuidle menu - * governor, are using nonsensical data. Preferring shallow idle state selection - * for a CPU that has IO-wait which might not even end up running the task when - * it does become runnable. + * Return whether any tasks are accounted as I/O waiters on this CPU. + * They may wake up on a different CPU. */ - -unsigned int nr_iowait_cpu(int cpu) +bool cpu_has_iowait(int cpu) { - return atomic_read(&cpu_rq(cpu)->nr_iowait); + return atomic_read(&cpu_rq(cpu)->nr_iowait) != 0; } /* @@ -5684,7 +5681,7 @@ unsigned int nr_iowait(void) unsigned int i, sum = 0; for_each_possible_cpu(i) - sum += nr_iowait_cpu(i); + sum += atomic_read(&cpu_rq(i)->nr_iowait); return sum; } @@ -10786,11 +10783,10 @@ static void __mm_update_max_cids(struct mm_mm_cid *mc) static inline unsigned int mm_cid_calc_pcpu_thrs(struct mm_mm_cid *mc) { - unsigned int opt_cids; + unsigned int nr_cpus = mc->nr_cpus_allowed; - opt_cids = min(mc->nr_cpus_allowed, mc->users); /* Has to be at least 1 because 0 indicates PCPU mode off */ - return max(min(opt_cids - opt_cids / 4, num_possible_cpus() / 2), 1); + return max(min(nr_cpus - nr_cpus / 4, num_possible_cpus() / 2), 1); } static bool mm_update_max_cids(struct mm_struct *mm) @@ -11261,18 +11257,17 @@ void sched_change_end(struct sched_change_ctx *ctx) if (p->sched_class->switched_to) p->sched_class->switched_to(rq, p); + /* + * Check if the task can preempt the current in case the class + * was upgraded. Note that none of the switch*_from() methods + * know the new class and none of the switch*_to() methods know + * the old class so we must resched here. + */ + if (ctx->queued) + wakeup_preempt(rq, p, 0); + if (ctx->running) { /* - * If this was a class promotion; let the old class - * know it got preempted. Note that none of the - * switch*_from() methods know the new class and none - * of the switch*_to() methods know the old class. - */ - if (sched_class_above(p->sched_class, ctx->class)) { - rq->next_class->wakeup_preempt(rq, p, 0); - rq->next_class = p->sched_class; - } - /* * If this was a degradation in class; make sure to * reschedule. */ |