Commit 51d48dab authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring: add more likely/unlikely() annotations 



Add two extra unlikely() in io_submit_sqes() and one around
io_req_needs_clean() to help the compiler to avoid extra jumps
in hot paths.

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/88e087afe657e7660194353aada9b00f11d480f9.1633373302.git.asml.silence@gmail.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 7e3709d5

fs/io_uring.c

+3 −3
Original line number Diff line number Diff line
@@ -1957,7 +1957,7 @@ static inline void io_dismantle_req(struct io_kiocb *req) 
{

	unsigned int flags = req->flags;



	if (io_req_needs_clean(req))

	if (unlikely(io_req_needs_clean(req)))

		io_clean_op(req);

	if (!(flags & REQ_F_FIXED_FILE))

		io_put_file(req->file);
@@ -7198,11 +7198,11 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr) 
	unsigned int entries = io_sqring_entries(ctx);

	int submitted = 0;



	if (!entries)

	if (unlikely(!entries))

		return 0;

	/* make sure SQ entry isn't read before tail */

	nr = min3(nr, ctx->sq_entries, entries);

	if (!percpu_ref_tryget_many(&ctx->refs, nr))

	if (unlikely(!percpu_ref_tryget_many(&ctx->refs, nr)))

		return -EAGAIN;

	io_get_task_refs(nr);