Re: [PATCH] io_uring: update sq_thread_idle after ctx deleted

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

On 4/24/21 10:26 AM, Hao Xu wrote:
> we shall update sq_thread_idle anytime we do ctx deletion from ctx_list

looks good, a nit below

> 
> Fixes:734551df6f9b ("io_uring: fix shared sqpoll cancellation hangs")
> Signed-off-by: Hao Xu <haoxu@linux.alibaba.com>
> ---
>  fs/io_uring.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/io_uring.c b/fs/io_uring.c
> index 40f38256499c..15f204274761 100644
> --- a/fs/io_uring.c
> +++ b/fs/io_uring.c
> @@ -8867,6 +8867,7 @@ static void io_sqpoll_cancel_cb(struct callback_head *cb)
>  	if (sqd->thread)
>  		io_uring_cancel_sqpoll(sqd);
>  	list_del_init(&work->ctx->sqd_list);
> +	io_sqd_update_thread_idle(sqd);
>  	complete(&work->completion);
>  }
>  
> @@ -8877,7 +8878,6 @@ static void io_sqpoll_cancel_sync(struct io_ring_ctx *ctx)
>  	struct task_struct *task;
>  
>  	io_sq_thread_park(sqd);
> -	io_sqd_update_thread_idle(sqd);
>  	task = sqd->thread;
>  	if (task) {
>  		init_completion(&work.completion);
> @@ -8886,6 +8886,7 @@ static void io_sqpoll_cancel_sync(struct io_ring_ctx *ctx)
>  		wake_up_process(task);
>  	} else {
>  		list_del_init(&ctx->sqd_list);
> +		io_sqd_update_thread_idle(sqd);

Not actually needed, it's already dying.

>  	}
>  	io_sq_thread_unpark(sqd);
>  
> 

-- 
Pavel Begunkov