Messages in this thread | | | Subject | Re: [PATCH net-next] tuntap: XDP_TX can use native XDP | From | Jason Wang <> | Date | Fri, 16 Mar 2018 14:46:22 +0800 |
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On 2018年03月15日 21:32, Michael S. Tsirkin wrote: > On Thu, Mar 15, 2018 at 04:39:25PM +0800, Jason Wang wrote: >> >> On 2018年03月14日 11:37, Michael S. Tsirkin wrote: >>>> return NULL; >>>> case XDP_TX: >>>> - xdp_xmit = true; >>>> - /* fall through */ >>>> + get_page(alloc_frag->page); >>>> + alloc_frag->offset += buflen; >>>> + if (tun_xdp_xmit(tun->dev, &xdp)) >>>> + goto err_redirect; >>>> + tun_xdp_flush(tun->dev); >>> Why do we have to flush here though? >>> It might be a good idea to document the reason in a code comment. >>> >> ndo_xdp_xmit() does not touch doorbell, so we need a ndo_xdp_flush() here. >> It's the assumption of XDP API I think, so not sure it's worth to mention it >> here. >> >> Thanks > Can't one flush we called after multiple xmit calls?
We can and could be another patch on top. But I want to unify it with the batching of XDP_REDIRECT by e.g let vhost submit more than one packets through msg.control in sendmsg().
Thanks
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