Re: [PATCH] io_uring/napi: remove duplicate io_napi_entry timeout assignation

[Olivier Langlois <olivier@trillion01.com>]

On Sun, 2024-08-11 at 20:34 -0400, Olivier Langlois wrote:
> io_napi_entry() has 2 calling sites. One of them is unlikely to find
> an
> entry and if it does, the timeout should arguable not be updated.
> 
> The other io_napi_entry() calling site is overwriting the update made
> by io_napi_entry() so the io_napi_entry() timeout value update has no
> or
> little value and therefore is removed.
> 
> Signed-off-by: Olivier Langlois <olivier@trillion01.com>
> ---
>  io_uring/napi.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/io_uring/napi.c b/io_uring/napi.c
> index 73c4159e8405..1de1d4d62925 100644
> --- a/io_uring/napi.c
> +++ b/io_uring/napi.c
> @@ -26,7 +26,6 @@ static struct io_napi_entry
> *io_napi_hash_find(struct hlist_head *hash_list,
>  	hlist_for_each_entry_rcu(e, hash_list, node) {
>  		if (e->napi_id != napi_id)
>  			continue;
> -		e->timeout = jiffies + NAPI_TIMEOUT;
>  		return e;
>  	}
>  
I am commenting my own patch because I found something curious that I
was not sure about when I was reviewing the code.

Should the remaining e->timeout assignation be wrapped with a
WRITE_ONCE() macro to ensure an atomic store?