From: Hillf Danton <hdanton@sina.com>
To: linux-kernel <linux-kernel@vger.kernel.org>
Cc: linux-mm <linux-mm@kvack.org>, Hillf Danton <hdanton@sina.com>
Subject: [RFC] workqueue: fix detecting reentrance
Date: Thu, 12 Dec 2019 17:15:48 +0800 [thread overview]
Message-ID: <20191212091548.21668-1-hdanton@sina.com> (raw)
If we can find a valid worker that is serving the specified work at
the moment then the worker itself is enough to ensure reentrance and
workqueue doesn't matter here because it is permitted for a work to
requeue itself either on different cpu or numa node or even on another
workqueue.
Fixes: c9178087acd7 ("workqueue: perform non-reentrancy test when queueing to unbound workqueues too")
Fixes: 18aa9effad4a ("workqueue: implement WQ_NON_REENTRANT")
Signed-off-by: Hillf Danton <hdanton@sina.com>
---
--- f/kernel/workqueue.c
+++ g/kernel/workqueue.c
@@ -1433,7 +1433,7 @@ retry:
worker = find_worker_executing_work(last_pool, work);
- if (worker && worker->current_pwq->wq == wq) {
+ if (worker) {
pwq = worker->current_pwq;
} else {
/* meh... not running there, queue here */
next reply other threads:[~2019-12-12 9:16 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-12 9:15 Hillf Danton [this message]
2019-12-16 14:02 ` Michal Hocko
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