io_uring: don't split out consume out of SQE get
Remove io_consume_sqe() and inline it back into io_get_sqe(). It
requires req dealloc on error, but in exchange we get cleaner
io_submit_sqes() and better locality for cached_sq_head.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 87f2f8e..9c58be0 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -6762,7 +6762,7 @@ static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx)
* 2) allows the kernel side to track the head on its own, even
* though the application is the one updating it.
*/
- head = READ_ONCE(sq_array[ctx->cached_sq_head & ctx->sq_mask]);
+ head = READ_ONCE(sq_array[ctx->cached_sq_head++ & ctx->sq_mask]);
if (likely(head < ctx->sq_entries))
return &ctx->sq_sqes[head];
@@ -6772,11 +6772,6 @@ static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx)
return NULL;
}
-static inline void io_consume_sqe(struct io_ring_ctx *ctx)
-{
- ctx->cached_sq_head++;
-}
-
/*
* Check SQE restrictions (opcode and flags).
*
@@ -6915,18 +6910,17 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr)
struct io_kiocb *req;
int err;
- sqe = io_get_sqe(ctx);
- if (unlikely(!sqe)) {
- io_consume_sqe(ctx);
- break;
- }
req = io_alloc_req(ctx);
if (unlikely(!req)) {
if (!submitted)
submitted = -EAGAIN;
break;
}
- io_consume_sqe(ctx);
+ sqe = io_get_sqe(ctx);
+ if (unlikely(!sqe)) {
+ kmem_cache_free(req_cachep, req);
+ break;
+ }
/* will complete beyond this point, count as submitted */
submitted++;
