io_uring/futex: Allocate ifd with generic alloc_cache helper

Instead of open-coding the allocation, use the generic alloc_cache
helper.

Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
Link: https://lore.kernel.org/r/20241216204615.759089-4-krisman@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Author: krisman

io_uring/futex.c

@@ -251,17 +251,6 @@ static void io_futex_wake_fn(struct wake_q_head *wake_q, struct futex_q *q)
 	io_req_task_work_add(req);
 }
 
-static struct io_futex_data *io_alloc_ifd(struct io_ring_ctx *ctx)
-{
-	struct io_futex_data *ifd;
-
-	ifd = io_alloc_cache_get(&ctx->futex_cache);
-	if (ifd)
-		return ifd;
-
-	return kmalloc(sizeof(struct io_futex_data), GFP_NOWAIT);
-}
-
 int io_futexv_wait(struct io_kiocb *req, unsigned int issue_flags)
 {
 	struct io_futex *iof = io_kiocb_to_cmd(req, struct io_futex);
@@ -331,7 +320,7 @@ int io_futex_wait(struct io_kiocb *req, unsigned int issue_flags)
 	}
 
 	io_ring_submit_lock(ctx, issue_flags);
-	ifd = io_alloc_ifd(ctx);
+	ifd = io_cache_alloc(&ctx->futex_cache, GFP_NOWAIT, NULL);
 	if (!ifd) {
 		ret = -ENOMEM;
 		goto done_unlock;