diff options
| author | Lai Jiangshan <jiangshan.ljs@antgroup.com> | 2024-07-03 17:27:41 +0800 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2024-07-14 18:20:19 -1000 |
| commit | 58629d4871e8eb2c385b16a73a8451669db59f39 (patch) | |
| tree | b8df40049d0db437705e08cf9e2bab2a45c2ab99 | |
| parent | b2b1f9338400de0fb65e2ff5fab1b5617dcb5a97 (diff) | |
workqueue: Always queue work items to the newest PWQ for order workqueues
To ensure non-reentrancy, __queue_work() attempts to enqueue a work
item to the pool of the currently executing worker. This is not only
unnecessary for an ordered workqueue, where order inherently suggests
non-reentrancy, but it could also disrupt the sequence if the item is
not enqueued on the newest PWQ.
Just queue it to the newest PWQ and let order management guarantees
non-reentrancy.
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Fixes: 4c065dbce1e8 ("workqueue: Enable unbound cpumask update on ordered workqueues")
Cc: stable@vger.kernel.org # v6.9+
Signed-off-by: Tejun Heo <tj@kernel.org>
(cherry picked from commit 74347be3edfd11277799242766edf844c43dd5d3)
| -rw-r--r-- | kernel/workqueue.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 79a178500a77..e3ab09e70ba9 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -2274,9 +2274,13 @@ retry: * If @work was previously on a different pool, it might still be * running there, in which case the work needs to be queued on that * pool to guarantee non-reentrancy. + * + * For ordered workqueue, work items must be queued on the newest pwq + * for accurate order management. Guaranteed order also guarantees + * non-reentrancy. See the comments above unplug_oldest_pwq(). */ last_pool = get_work_pool(work); - if (last_pool && last_pool != pool) { + if (last_pool && last_pool != pool && !(wq->flags & __WQ_ORDERED)) { struct worker *worker; raw_spin_lock(&last_pool->lock); |