Commit af9c1a44 authored by Jens Axboe's avatar Jens Axboe
Browse files

io_uring: process task work in io_uring_register() 



We do this for CQ ring wait, in case task_work completions come in. We
should do the same in io_uring_register(), to avoid spurious -EINTR
if the ring quiescing ends up having to process task_work to complete
the operation

Reported-by: default avatarDan Melnic <dmm@fb.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 91d8f519

fs/io_uring.c

+28 −12
Original line number Diff line number Diff line
@@ -6950,6 +6950,22 @@ static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode, 
	return autoremove_wake_function(curr, mode, wake_flags, key);

}



static int io_run_task_work_sig(void)

{

	if (io_run_task_work())

		return 1;

	if (!signal_pending(current))

		return 0;

	if (current->jobctl & JOBCTL_TASK_WORK) {

		spin_lock_irq(&current->sighand->siglock);

		current->jobctl &= ~JOBCTL_TASK_WORK;

		recalc_sigpending();

		spin_unlock_irq(&current->sighand->siglock);

		return 1;

	}

	return -EINTR;

}



/*

 * Wait until events become available, if we don't already have some. The

 * application must reap them itself, as they reside on the shared cq ring.
@@ -6995,19 +7011,11 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, 
		prepare_to_wait_exclusive(&ctx->wait, &iowq.wq,

						TASK_INTERRUPTIBLE);

		/* make sure we run task_work before checking for signals */

		if (io_run_task_work())

			continue;

		if (signal_pending(current)) {

			if (current->jobctl & JOBCTL_TASK_WORK) {

				spin_lock_irq(&current->sighand->siglock);

				current->jobctl &= ~JOBCTL_TASK_WORK;

				recalc_sigpending();

				spin_unlock_irq(&current->sighand->siglock);

		ret = io_run_task_work_sig();

		if (ret > 0)

			continue;

			}

			ret = -EINTR;

		else if (ret < 0)

			break;

		}

		if (io_should_wake(&iowq, false))

			break;

		schedule();
@@ -9666,8 +9674,16 @@ static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode, 
		 * after we've killed the percpu ref.

		 */

		mutex_unlock(&ctx->uring_lock);

		do {

			ret = wait_for_completion_interruptible(&ctx->ref_comp);

			if (!ret)

				break;

			if (io_run_task_work_sig() > 0)

				continue;

		} while (1);



		mutex_lock(&ctx->uring_lock);



		if (ret) {

			percpu_ref_resurrect(&ctx->refs);

			ret = -EINTR;