[PATCH 3/3] io_uring: inform block layer of how many requests we are submitting

[Jens Axboe <axboe@kernel.dk>]

The block layer can use this knowledge to make smarter decisions on
how to handle the request, if it knows that N more may be coming. Switch
to using blk_start_plug_nr_ios() to pass in that information.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 fs/io_uring.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 62dc128e9b6b..c35b0f230be8 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -314,6 +314,8 @@ struct io_submit_state {
 	bool			plug_started;
 	bool			need_plug;
 
+	unsigned short		submit_nr;
+
 	/*
 	 * Batch completion logic
 	 */
@@ -7035,7 +7037,7 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
 	 * is potentially a read/write to block based storage.
 	 */
 	if (state->need_plug && io_op_defs[req->opcode].plug) {
-		blk_start_plug(&state->plug);
+		blk_start_plug_nr_ios(&state->plug, state->submit_nr);
 		state->plug_started = true;
 		state->need_plug = false;
 	}
@@ -7150,6 +7152,7 @@ static void io_submit_state_start(struct io_submit_state *state,
 {
 	state->plug_started = false;
 	state->need_plug = max_ios > 2;
+	state->submit_nr = max_ios;
 	/* set only head, no need to init link_last in advance */
 	state->link.head = NULL;
 }
-- 
2.33.0