Commit 76cc33d7 authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring: refactor io_req_defer() 



Rename io_req_defer() into io_drain_req() and refactor it uncoupling it
from io_queue_sqe() error handling and preparing for coming
optimisations. Also, prioritise non IOSQE_ASYNC path.

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/4f17dd56e7fbe52d1866f8acd8efe3284d2bebcb.1623709150.git.asml.silence@gmail.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 0499e582

fs/io_uring.c

+19 −20
Original line number Diff line number Diff line
@@ -5998,7 +5998,7 @@ static u32 io_get_sequence(struct io_kiocb *req) 
	return ctx->cached_sq_head - nr_reqs;

}



static int io_req_defer(struct io_kiocb *req)

static bool io_drain_req(struct io_kiocb *req)

{

	struct io_ring_ctx *ctx = req->ctx;

	struct io_defer_entry *de;
@@ -6008,27 +6008,29 @@ static int io_req_defer(struct io_kiocb *req) 
	/* Still need defer if there is pending req in defer list. */

	if (likely(list_empty_careful(&ctx->defer_list) &&

		!(req->flags & REQ_F_IO_DRAIN)))

		return 0;

		return false;



	seq = io_get_sequence(req);

	/* Still a chance to pass the sequence check */

	if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list))

		return 0;

		return false;



	ret = io_req_prep_async(req);

	if (ret)

		return ret;

	io_prep_async_link(req);

	de = kmalloc(sizeof(*de), GFP_KERNEL);

	if (!de)

		return -ENOMEM;

	if (!de) {

		io_req_complete_failed(req, ret);

		return true;

	}



	spin_lock_irq(&ctx->completion_lock);

	if (!req_need_defer(req, seq) && list_empty(&ctx->defer_list)) {

		spin_unlock_irq(&ctx->completion_lock);

		kfree(de);

		io_queue_async_work(req);

		return -EIOCBQUEUED;

		return true;

	}



	trace_io_uring_defer(ctx, req, req->user_data);
@@ -6036,7 +6038,7 @@ static int io_req_defer(struct io_kiocb *req) 
	de->seq = seq;

	list_add_tail(&de->list, &ctx->defer_list);

	spin_unlock_irq(&ctx->completion_lock);

	return -EIOCBQUEUED;

	return true;

}



static void io_clean_op(struct io_kiocb *req)
@@ -6447,21 +6449,18 @@ static void __io_queue_sqe(struct io_kiocb *req) 


static void io_queue_sqe(struct io_kiocb *req)

{

	int ret;

	if (io_drain_req(req))

		return;



	if (likely(!(req->flags & REQ_F_FORCE_ASYNC))) {

		__io_queue_sqe(req);

	} else {

		int ret = io_req_prep_async(req);



	ret = io_req_defer(req);

	if (ret) {

		if (ret != -EIOCBQUEUED) {

fail_req:

			io_req_complete_failed(req, ret);

		}

	} else if (req->flags & REQ_F_FORCE_ASYNC) {

		ret = io_req_prep_async(req);

		if (unlikely(ret))

			goto fail_req;

			io_req_complete_failed(req, ret);

		else

			io_queue_async_work(req);

	} else {

		__io_queue_sqe(req);

	}

}