hulk inclusion category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I7ZMCB CVE: NA -------------------------------- CPU hotplug callbacks race against distribute_cfs_runtime(), when the QOS_SCHED feature is enabled, there may be situations where the cfs_rq-> runtime_remaining == 1 and cfs_rq is QOS_THROTTLED. Turn off the Qos_throttle when the CPU is offline. No longer allocate time to cfs_rq in this scenario to fix the warning. Fixes: 4eb6eb7941dc ("sched/qos: Don't unthrottle cfs_rq when cfs_rq is throttled by qos") Signed-off-by: Xia Fukun <xiafukun@huawei.com> --- kernel/sched/fair.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index daa853b19853..b8bf7acb9f9a 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5267,6 +5267,19 @@ static void distribute_cfs_runtime(struct cfs_bandwidth *cfs_b) if (!cfs_rq_throttled(cfs_rq)) goto next; + /* + * CPU hotplug callbacks race against distribute_cfs_runtime() + * when the QOS_SCHED feature is enabled, there may be + * situations where the runtime_remaining > 0. + * Qos_sched does not care whether the cfs_rq has time left, + * so no longer allocate time to cfs_rq in this scenario. + */ +#ifdef CONFIG_QOS_SCHED + if (cfs_rq->throttled == QOS_THROTTLED && + cfs_rq->runtime_remaining > 0) + goto next; +#endif + /* By the above check, this should never be true */ SCHED_WARN_ON(cfs_rq->runtime_remaining > 0); @@ -7923,6 +7936,10 @@ static __always_inline bool check_qos_cfs_rq(struct cfs_rq *cfs_rq) if (unlikely(cfs_rq && is_offline_level(cfs_rq->tg->qos_level) && !sched_idle_cpu(smp_processor_id()) && cfs_rq->h_nr_running == cfs_rq->idle_h_nr_running)) { + + if (!rq_of(cfs_rq)->online) + return false; + throttle_qos_cfs_rq(cfs_rq); return true; } -- 2.34.1