On 10/16/24 20:52, David Wei wrote:
> @@ -540,6 +562,34 @@ static const struct memory_provider_ops io_uring_pp_zc_ops = {
> .scrub = io_pp_zc_scrub,
> };
>
> +static void io_napi_refill(void *data)
> +{
> + struct io_zc_refill_data *rd = data;
> + struct io_zcrx_ifq *ifq = rd->ifq;
> + netmem_ref netmem;
> +
> + if (WARN_ON_ONCE(!ifq->pp))
> + return;
> +
> + netmem = page_pool_alloc_netmem(ifq->pp, GFP_ATOMIC | __GFP_NOWARN);
> + if (!netmem)
> + return;
> + if (WARN_ON_ONCE(!netmem_is_net_iov(netmem)))
> + return;
> +
> + rd->niov = netmem_to_net_iov(netmem);
> +}
> +
> +static struct net_iov *io_zc_get_buf_task_safe(struct io_zcrx_ifq *ifq)
> +{
> + struct io_zc_refill_data rd = {
> + .ifq = ifq,
> + };
> +
> + napi_execute(ifq->napi_id, io_napi_refill, &rd);
Under UDP flood the above has unbounded/unlimited execution time, unless
you set NAPI_STATE_PREFER_BUSY_POLL. Is the allocation schema here
somehow preventing such unlimited wait?
Thanks,
Paolo
