io_uring: remove extra check in __io_commit_cqring

__io_commit_cqring() is almost always called when there is a change in
the rings, so the check is rather pessimising.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

fs/io_uring.c

@@ -860,14 +860,12 @@ static void __io_commit_cqring(struct io_ring_ctx *ctx)
 {
 	struct io_rings *rings = ctx->rings;
 
-	if (ctx->cached_cq_tail != READ_ONCE(rings->cq.tail)) {
-		/* order cqe stores with ring update */
-		smp_store_release(&rings->cq.tail, ctx->cached_cq_tail);
+	/* order cqe stores with ring update */
+	smp_store_release(&rings->cq.tail, ctx->cached_cq_tail);
 
-		if (wq_has_sleeper(&ctx->cq_wait)) {
-			wake_up_interruptible(&ctx->cq_wait);
-			kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
-		}
+	if (wq_has_sleeper(&ctx->cq_wait)) {
+		wake_up_interruptible(&ctx->cq_wait);
+		kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
 	}
 }