io_uring: deduplicate wakeup handling

Both io_poll_wq_wake() and io_cqring_wake() contain the exact same code,
and most of the comment in the latter applies equally to both.

Move the test and wakeup handling into a basic helper that they can both
use, and move part of the comment that applies generically to this new
helper.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/io_uring.h b/io_uring/io_uring.h
index dc17162e7af1de01c9f95abff41f3c6a146adc6a..abc6de227f74d23bbca84b761324072135932da7 100644 (file)
--- a/io_uring/io_uring.h
+++ b/io_uring/io_uring.h
@@ -294,11 +294,22 @@ static inline void io_commit_cqring(struct io_ring_ctx *ctx)
        smp_store_release(&ctx->rings->cq.tail, ctx->cached_cq_tail);
 }
 
+static inline void __io_wq_wake(struct wait_queue_head *wq)
+{
+       /*
+        *
+        * Pass in EPOLLIN|EPOLL_URING_WAKE as the poll wakeup key. The latter
+        * set in the mask so that if we recurse back into our own poll
+        * waitqueue handlers, we know we have a dependency between eventfd or
+        * epoll and should terminate multishot poll at that point.
+        */
+       if (wq_has_sleeper(wq))
+               __wake_up(wq, TASK_NORMAL, 0, poll_to_key(EPOLL_URING_WAKE | EPOLLIN));
+}
+
 static inline void io_poll_wq_wake(struct io_ring_ctx *ctx)
 {
-       if (wq_has_sleeper(&ctx->poll_wq))
-               __wake_up(&ctx->poll_wq, TASK_NORMAL, 0,
-                               poll_to_key(EPOLL_URING_WAKE | EPOLLIN));
+       __io_wq_wake(&ctx->poll_wq);
 }
 
 static inline void io_cqring_wake(struct io_ring_ctx *ctx)
@@ -307,15 +318,9 @@ static inline void io_cqring_wake(struct io_ring_ctx *ctx)
         * Trigger waitqueue handler on all waiters on our waitqueue. This
         * won't necessarily wake up all the tasks, io_should_wake() will make
         * that decision.
-        *
-        * Pass in EPOLLIN|EPOLL_URING_WAKE as the poll wakeup key. The latter
-        * set in the mask so that if we recurse back into our own poll
-        * waitqueue handlers, we know we have a dependency between eventfd or
-        * epoll and should terminate multishot poll at that point.
         */
-       if (wq_has_sleeper(&ctx->cq_wait))
-               __wake_up(&ctx->cq_wait, TASK_NORMAL, 0,
-                               poll_to_key(EPOLL_URING_WAKE | EPOLLIN));
+
+       __io_wq_wake(&ctx->cq_wait);
 }
 
 static inline bool io_sqring_full(struct io_ring_ctx *ctx)