diff options
Diffstat (limited to 'kernel/workqueue.c')
-rw-r--r-- | kernel/workqueue.c | 47 |
1 files changed, 34 insertions, 13 deletions
diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 18fae55713b0..cf5d8fd7472e 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -49,6 +49,7 @@ #include <linux/moduleparam.h> #include <linux/uaccess.h> #include <linux/nmi.h> +#include <linux/kvm_para.h> #include "workqueue_internal.h" @@ -1379,7 +1380,6 @@ static void __queue_work(int cpu, struct workqueue_struct *wq, */ WARN_ON_ONCE(!irqs_disabled()); - debug_work_activate(work); /* if draining, only works from the same workqueue are allowed */ if (unlikely(wq->flags & __WQ_DRAINING) && @@ -1462,6 +1462,7 @@ retry: worklist = &pwq->delayed_works; } + debug_work_activate(work); insert_work(pwq, work, worklist, work_flags); spin_unlock(&pwq->pool->lock); @@ -3440,15 +3441,21 @@ static void pwq_unbound_release_workfn(struct work_struct *work) unbound_release_work); struct workqueue_struct *wq = pwq->wq; struct worker_pool *pool = pwq->pool; - bool is_last; + bool is_last = false; - if (WARN_ON_ONCE(!(wq->flags & WQ_UNBOUND))) - return; + /* + * when @pwq is not linked, it doesn't hold any reference to the + * @wq, and @wq is invalid to access. + */ + if (!list_empty(&pwq->pwqs_node)) { + if (WARN_ON_ONCE(!(wq->flags & WQ_UNBOUND))) + return; - mutex_lock(&wq->mutex); - list_del_rcu(&pwq->pwqs_node); - is_last = list_empty(&wq->pwqs); - mutex_unlock(&wq->mutex); + mutex_lock(&wq->mutex); + list_del_rcu(&pwq->pwqs_node); + is_last = list_empty(&wq->pwqs); + mutex_unlock(&wq->mutex); + } mutex_lock(&wq_pool_mutex); put_unbound_pool(pool); @@ -3494,17 +3501,24 @@ static void pwq_adjust_max_active(struct pool_workqueue *pwq) * is updated and visible. */ if (!freezable || !workqueue_freezing) { + bool kick = false; + pwq->max_active = wq->saved_max_active; while (!list_empty(&pwq->delayed_works) && - pwq->nr_active < pwq->max_active) + pwq->nr_active < pwq->max_active) { pwq_activate_first_delayed(pwq); + kick = true; + } /* * Need to kick a worker after thawed or an unbound wq's - * max_active is bumped. It's a slow path. Do it always. + * max_active is bumped. In realtime scenarios, always kicking a + * worker will cause interference on the isolated cpu cores, so + * let's kick iff work items were activated. */ - wake_up_worker(pwq->pool); + if (kick) + wake_up_worker(pwq->pool); } else { pwq->max_active = 0; } @@ -5458,6 +5472,7 @@ static void wq_watchdog_timer_fn(unsigned long data) { unsigned long thresh = READ_ONCE(wq_watchdog_thresh) * HZ; bool lockup_detected = false; + unsigned long now = jiffies; struct worker_pool *pool; int pi; @@ -5472,6 +5487,12 @@ static void wq_watchdog_timer_fn(unsigned long data) if (list_empty(&pool->worklist)) continue; + /* + * If a virtual machine is stopped by the host it can look to + * the watchdog like a stall. + */ + kvm_check_and_clear_guest_paused(); + /* get the latest of pool and touched timestamps */ pool_ts = READ_ONCE(pool->watchdog_ts); touched = READ_ONCE(wq_watchdog_touched); @@ -5490,12 +5511,12 @@ static void wq_watchdog_timer_fn(unsigned long data) } /* did we stall? */ - if (time_after(jiffies, ts + thresh)) { + if (time_after(now, ts + thresh)) { lockup_detected = true; pr_emerg("BUG: workqueue lockup - pool"); pr_cont_pool_info(pool); pr_cont(" stuck for %us!\n", - jiffies_to_msecs(jiffies - pool_ts) / 1000); + jiffies_to_msecs(now - pool_ts) / 1000); } } |