[PATCH 5/6] io_uring: add fast path for io_run_local_work()

Pavel Begunkov
2022-09-08T15:59:10Z

We'll grab uring_lock and call __io_run_local_work() with several
atomics inside even if there are no task works. Skip it if ->work_llist
is empty.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
io_uring/io_uring.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 2fb5f1e78fb2..85b795e4dc6a 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -1208,6 +1208,9 @@ int io_run_local_work(struct io_ring_ctx *ctx)
bool locked;
int ret;

+ if (llist_empty(&ctx->work_llist))
+ return 0;
+
locked = mutex_trylock(&ctx->uring_lock);
ret = __io_run_local_work(ctx, locked);
if (locked)
--
2.37.2