io_uring: don't use complete_all() on SQPOLL thread exit

We want to reuse this completion, and a single complete should do just
fine. Ensure that we park ourselves first if requested, as that is what
lead to the initial deadlock in this area. If we've got someone attempting
to park us, then we can't proceed without having them finish first.

Fixes: 37d1e2e364 ("io_uring: move SQPOLL thread io-wq forked worker")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2021-02-26 13:46:49 -07:00
parent ba50a036f2
commit 8629397e6e

View File

@ -6783,10 +6783,13 @@ static int io_sq_thread(void *data)
io_run_task_work();
if (io_sq_thread_should_park(sqd))
io_sq_thread_parkme(sqd);
/*
* Clear thread under lock so that concurrent parks work correctly
*/
complete_all(&sqd->completion);
complete(&sqd->completion);
mutex_lock(&sqd->lock);
sqd->thread = NULL;
list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {