| Message ID | 20191212091548.21668-1-hdanton@sina.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [RFC] workqueue: fix detecting reentrance | expand |
Cc maintainers. On Thu 12-12-19 17:15:48, Hillf Danton wrote: > > 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. I do not follow what is the actual problem you are trying to fix here. > 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 */ >
--- 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 */
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> ---