io_uring: use wait_event_interruptible for cq_wait conditional wait

The previous patch has ensured that io_cqring_events contain
smp_rmb memory barriers, Now we can use wait_event_interruptible
to keep the code simple.

Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 9cc7a10..383d208 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2181,7 +2181,6 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
 {
        struct io_cq_ring *ring = ctx->cq_ring;
        sigset_t ksigmask, sigsaved;
-       DEFINE_WAIT(wait);
        int ret;
 
        if (io_cqring_events(ring) >= min_events)
@@ -2201,21 +2200,9 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
                        return ret;
        }
 
-       do {
-               prepare_to_wait(&ctx->wait, &wait, TASK_INTERRUPTIBLE);
-
-               ret = 0;
-               if (io_cqring_events(ring) >= min_events)
-                       break;
-
-               schedule();
-
+       ret = wait_event_interruptible(ctx->wait, io_cqring_events(ring) >= min_events);
+       if (ret == -ERESTARTSYS)
                ret = -EINTR;
-               if (signal_pending(current))
-                       break;
-       } while (1);
-
-       finish_wait(&ctx->wait, &wait);
 
        if (sig)
                restore_user_sigmask(sig, &sigsaved);