summaryrefslogtreecommitdiff
path: root/kernel/workqueue.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/workqueue.c')
-rw-r--r--kernel/workqueue.c38
1 files changed, 30 insertions, 8 deletions
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 08bc551976b2..a37f5dc7cb39 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -2366,8 +2366,14 @@ repeat:
*/
if (need_to_create_worker(pool)) {
spin_lock(&wq_mayday_lock);
- get_pwq(pwq);
- list_move_tail(&pwq->mayday_node, &wq->maydays);
+ /*
+ * Queue iff we aren't racing destruction
+ * and somebody else hasn't queued it already.
+ */
+ if (wq->rescuer && list_empty(&pwq->mayday_node)) {
+ get_pwq(pwq);
+ list_add_tail(&pwq->mayday_node, &wq->maydays);
+ }
spin_unlock(&wq_mayday_lock);
}
}
@@ -4084,9 +4090,29 @@ void destroy_workqueue(struct workqueue_struct *wq)
struct pool_workqueue *pwq;
int node;
+ /*
+ * Remove it from sysfs first so that sanity check failure doesn't
+ * lead to sysfs name conflicts.
+ */
+ workqueue_sysfs_unregister(wq);
+
/* drain it before proceeding with destruction */
drain_workqueue(wq);
+ /* kill rescuer, if sanity checks fail, leave it w/o rescuer */
+ if (wq->rescuer) {
+ struct worker *rescuer = wq->rescuer;
+
+ /* this prevents new queueing */
+ spin_lock_irq(&wq_mayday_lock);
+ wq->rescuer = NULL;
+ spin_unlock_irq(&wq_mayday_lock);
+
+ /* rescuer will empty maydays list before exiting */
+ kthread_stop(rescuer->task);
+ kfree(rescuer);
+ }
+
/* sanity checks */
mutex_lock(&wq->mutex);
for_each_pwq(pwq, wq) {
@@ -4118,11 +4144,6 @@ void destroy_workqueue(struct workqueue_struct *wq)
list_del_rcu(&wq->list);
mutex_unlock(&wq_pool_mutex);
- workqueue_sysfs_unregister(wq);
-
- if (wq->rescuer)
- kthread_stop(wq->rescuer->task);
-
if (!(wq->flags & WQ_UNBOUND)) {
/*
* The base ref is never dropped on per-cpu pwqs. Directly
@@ -4399,7 +4420,8 @@ static void show_pwq(struct pool_workqueue *pwq)
pr_info(" pwq %d:", pool->id);
pr_cont_pool_info(pool);
- pr_cont(" active=%d/%d%s\n", pwq->nr_active, pwq->max_active,
+ pr_cont(" active=%d/%d refcnt=%d%s\n",
+ pwq->nr_active, pwq->max_active, pwq->refcnt,
!list_empty(&pwq->mayday_node) ? " MAYDAY" : "");
hash_for_each(pool->busy_hash, bkt, worker, hentry) {