Commit 529af6bc authored by Hui Tang's avatar Hui Tang Committed by Yipeng Zou
Browse files

sched: Fix timer storm for smart grid 

hulk inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7DSX6


CVE: NA

-------------------------------

Timer storm may be triggered if !cpumask_weight(ad->domains[i])
which is set in cpu offline.

Fixes: 713cfd26 ("sched: Introduce smart grid scheduling strategy for cfs")
Signed-off-by: default avatarHui Tang <tanghui20@huawei.com>
Reviewed-by: default avatarZhang Qiao <zhangqiao22@huawei.com>
Signed-off-by: default avatarZhang Changzhong <zhangchangzhong@huawei.com>
Signed-off-by: default avatarYipeng Zou <zouyipeng@huawei.com>
parent 7f91c253

kernel/sched/fair.c

+14 −18
Original line number Diff line number Diff line
@@ -5871,15 +5871,13 @@ static void affinity_domain_up(struct task_group *tg) 
		return;



	while (level < ad->dcount) {

		if (IS_DOMAIN_SET(level + 1, ad->domain_mask)) {

		if (IS_DOMAIN_SET(level + 1, ad->domain_mask) &&

		    cpumask_weight(ad->domains[level + 1]) > 0) {

			ad->curr_level = level + 1;

			break;

			return;

		}

		level++;

	}



	if (level == ad->dcount)

		return;

}



static void affinity_domain_down(struct task_group *tg)
@@ -5891,15 +5889,15 @@ static void affinity_domain_down(struct task_group *tg) 
		return;



	while (level > 0) {

		if (!cpumask_weight(ad->domains[level - 1]))

			return;



		if (IS_DOMAIN_SET(level - 1, ad->domain_mask)) {

			ad->curr_level = level - 1;

			break;

			return;

		}

		level--;

	}



	if (!level)

		return;

}



static enum hrtimer_restart sched_auto_affi_period_timer(struct hrtimer *timer)
@@ -5919,11 +5917,8 @@ static enum hrtimer_restart sched_auto_affi_period_timer(struct hrtimer *timer) 
		tg_capacity += capacity_of(cpu);

	}



	if (unlikely(!tg_capacity))

		return HRTIMER_RESTART;



	raw_spin_lock_irqsave(&auto_affi->lock, flags);

	if (util_avg_sum * 100 > tg_capacity * sysctl_sched_util_low_pct) {

	if (util_avg_sum * 100 >= tg_capacity * sysctl_sched_util_low_pct) {

		affinity_domain_up(tg);

	} else if (util_avg_sum * 100 < tg_capacity *

		   sysctl_sched_util_low_pct / 2) {
@@ -5955,15 +5950,16 @@ static int tg_update_affinity_domain_down(struct task_group *tg, void *data) 
			continue;



		/* online */

		if (cpu_state[1])

		if (cpu_state[1]) {

			cpumask_set_cpu(cpu_state[0], ad->domains[i]);

		else

		} else {

			cpumask_clear_cpu(cpu_state[0], ad->domains[i]);

			if (!cpumask_weight(ad->domains[i]))

				affinity_domain_up(tg);

		}

	raw_spin_unlock_irqrestore(&auto_affi->lock, flags);



	if (!smart_grid_used())

		return 0;

	}

	raw_spin_unlock_irqrestore(&auto_affi->lock, flags);



	return 0;

}