[PATCH v3] io_uring/futex: Factor out common free logic into io_free_ifd()

[Sidong Yang <sidong.yang@furiosa.ai>]

This patch introduces io_free_ifd() that try to cache or free
io_futex_data. It could be used for completion. It also could be used
for error path in io_futex_wait(). Old code just release the ifd but it
could be cached.

Signed-off-by: Sidong Yang <sidong.yang@furiosa.ai>
---
v2: use io_free_ifd() for completion
v3: format, inline, remove reduntant init.
---
 io_uring/futex.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/io_uring/futex.c b/io_uring/futex.c
index e29662f039e1..dcf57c7f2c68 100644
--- a/io_uring/futex.c
+++ b/io_uring/futex.c
@@ -44,6 +44,12 @@ void io_futex_cache_free(struct io_ring_ctx *ctx)
 	io_alloc_cache_free(&ctx->futex_cache, kfree);
 }
 
+inline static void io_free_ifd(struct io_ring_ctx *ctx, struct io_futex_data *ifd)
+{
+	if (!io_alloc_cache_put(&ctx->futex_cache, ifd))
+		kfree(ifd);
+}
+
 static void __io_futex_complete(struct io_kiocb *req, struct io_tw_state *ts)
 {
 	req->async_data = NULL;
@@ -57,8 +63,7 @@ static void io_futex_complete(struct io_kiocb *req, struct io_tw_state *ts)
 	struct io_ring_ctx *ctx = req->ctx;
 
 	io_tw_lock(ctx, ts);
-	if (!io_alloc_cache_put(&ctx->futex_cache, ifd))
-		kfree(ifd);
+	io_free_ifd(ctx, ifd);
 	__io_futex_complete(req, ts);
 }
 
@@ -321,7 +326,7 @@ int io_futex_wait(struct io_kiocb *req, unsigned int issue_flags)
 {
 	struct io_futex *iof = io_kiocb_to_cmd(req, struct io_futex);
 	struct io_ring_ctx *ctx = req->ctx;
-	struct io_futex_data *ifd = NULL;
+	struct io_futex_data *ifd;
 	struct futex_hash_bucket *hb;
 	int ret;
 
@@ -353,13 +358,13 @@ int io_futex_wait(struct io_kiocb *req, unsigned int issue_flags)
 		return IOU_ISSUE_SKIP_COMPLETE;
 	}
 
+	io_free_ifd(ctx, ifd);
 done_unlock:
 	io_ring_submit_unlock(ctx, issue_flags);
 done:
 	if (ret < 0)
 		req_set_fail(req);
 	io_req_set_res(req, ret, 0);
-	kfree(ifd);
 	return IOU_OK;
 }
 
-- 
2.43.0