Commit 81ec803b authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring: refactor io_disarm_next() locking 



Split timeout handling into removal + failing, so we can reduce
spinlocking time and remove another instance of triple nested locking.

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0f00d115f9d4c5749028f19623708ad3695512d6.1650458197.git.asml.silence@gmail.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 3645c200

fs/io_uring.c

+10 −7
Original line number Diff line number Diff line
@@ -2372,7 +2372,7 @@ static inline void io_remove_next_linked(struct io_kiocb *req) 
	nxt->link = NULL;

}



static bool io_kill_linked_timeout(struct io_kiocb *req)

static struct io_kiocb *io_disarm_linked_timeout(struct io_kiocb *req)

	__must_hold(&req->ctx->completion_lock)

	__must_hold(&req->ctx->timeout_lock)

{
@@ -2385,11 +2385,10 @@ static bool io_kill_linked_timeout(struct io_kiocb *req) 
		link->timeout.head = NULL;

		if (hrtimer_try_to_cancel(&io->timer) != -1) {

			list_del(&link->timeout.list);

			io_req_tw_post_queue(link, -ECANCELED, 0);

			return true;

			return link;

		}

	}

	return false;

	return NULL;

}



static void io_fail_links(struct io_kiocb *req)
@@ -2423,11 +2422,11 @@ static void io_fail_links(struct io_kiocb *req) 
static bool io_disarm_next(struct io_kiocb *req)

	__must_hold(&req->ctx->completion_lock)

{

	struct io_kiocb *link = NULL;

	bool posted = false;



	if (req->flags & REQ_F_ARM_LTIMEOUT) {

		struct io_kiocb *link = req->link;



		link = req->link;

		req->flags &= ~REQ_F_ARM_LTIMEOUT;

		if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {

			io_remove_next_linked(req);
@@ -2438,8 +2437,12 @@ static bool io_disarm_next(struct io_kiocb *req) 
		struct io_ring_ctx *ctx = req->ctx;



		spin_lock_irq(&ctx->timeout_lock);

		posted = io_kill_linked_timeout(req);

		link = io_disarm_linked_timeout(req);

		spin_unlock_irq(&ctx->timeout_lock);

		if (link) {

			posted = true;

			io_req_tw_post_queue(link, -ECANCELED, 0);

		}

	}

	if (unlikely((req->flags & REQ_F_FAIL) &&

		     !(req->flags & REQ_F_HARDLINK))) {