Re: [PATCH 1/1] io_uring: kill fasync

[Pavel Begunkov <asml.silence@gmail.com>]

On 10/1/21 10:39 AM, Pavel Begunkov wrote:
> We have never supported fasync properly, it would only fire when there
> is something polling io_uring making it useless. Get rid of fasync bits.

Actually, it looks there is something screwed, let's hold on this


> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
> ---
>  fs/io_uring.c | 17 ++---------------
>  1 file changed, 2 insertions(+), 15 deletions(-)
> 
> diff --git a/fs/io_uring.c b/fs/io_uring.c
> index c6a82c67a93d..f76a9b6bed2c 100644
> --- a/fs/io_uring.c
> +++ b/fs/io_uring.c
> @@ -398,7 +398,6 @@ struct io_ring_ctx {
>  		struct wait_queue_head	cq_wait;
>  		unsigned		cq_extra;
>  		atomic_t		cq_timeouts;
> -		struct fasync_struct	*cq_fasync;
>  		unsigned		cq_last_tm_flush;
>  	} ____cacheline_aligned_in_smp;
>  
> @@ -1614,10 +1613,8 @@ static void io_cqring_ev_posted(struct io_ring_ctx *ctx)
>  		wake_up(&ctx->sq_data->wait);
>  	if (io_should_trigger_evfd(ctx))
>  		eventfd_signal(ctx->cq_ev_fd, 1);
> -	if (waitqueue_active(&ctx->poll_wait)) {
> +	if (waitqueue_active(&ctx->poll_wait))
>  		wake_up_interruptible(&ctx->poll_wait);
> -		kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
> -	}
>  }
>  
>  static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx)
> @@ -1631,10 +1628,8 @@ static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx)
>  	}
>  	if (io_should_trigger_evfd(ctx))
>  		eventfd_signal(ctx->cq_ev_fd, 1);
> -	if (waitqueue_active(&ctx->poll_wait)) {
> +	if (waitqueue_active(&ctx->poll_wait))
>  		wake_up_interruptible(&ctx->poll_wait);
> -		kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
> -	}
>  }
>  
>  /* Returns true if there are no backlogged entries after the flush */
> @@ -9304,13 +9299,6 @@ static __poll_t io_uring_poll(struct file *file, poll_table *wait)
>  	return mask;
>  }
>  
> -static int io_uring_fasync(int fd, struct file *file, int on)
> -{
> -	struct io_ring_ctx *ctx = file->private_data;
> -
> -	return fasync_helper(fd, file, on, &ctx->cq_fasync);
> -}
> -
>  static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id)
>  {
>  	const struct cred *creds;
> @@ -10155,7 +10143,6 @@ static const struct file_operations io_uring_fops = {
>  	.mmap_capabilities = io_uring_nommu_mmap_capabilities,
>  #endif
>  	.poll		= io_uring_poll,
> -	.fasync		= io_uring_fasync,
>  #ifdef CONFIG_PROC_FS
>  	.show_fdinfo	= io_uring_show_fdinfo,
>  #endif
> 

-- 
Pavel Begunkov