From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Fastabend Subject: Re: [net PATCH v3 3/5] virtio_net: factor out xdp handler for readability Date: Fri, 13 Jan 2017 11:56:57 -0800 Message-ID: <58793109.8050405@gmail.com> References: <20170113024908.4535.8835.stgit@john-Precision-Tower-5810> <20170113025123.4535.75989.stgit@john-Precision-Tower-5810> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Cc: john.r.fastabend@intel.com, netdev@vger.kernel.org, alexei.starovoitov@gmail.com, daniel@iogearbox.net To: Jason Wang , mst@redhat.com Return-path: Received: from mail-pf0-f195.google.com ([209.85.192.195]:36073 "EHLO mail-pf0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750914AbdAMT5L (ORCPT ); Fri, 13 Jan 2017 14:57:11 -0500 Received: by mail-pf0-f195.google.com with SMTP id b22so9594864pfd.3 for ; Fri, 13 Jan 2017 11:57:11 -0800 (PST) In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On 17-01-12 11:40 PM, Jason Wang wrote: > > > On 2017年01月13日 10:51, John Fastabend wrote: >> At this point the do_xdp_prog is mostly if/else branches handling >> the different modes of virtio_net. So remove it and handle running >> the program in the per mode handlers. >> >> Signed-off-by: John Fastabend >> --- >> drivers/net/virtio_net.c | 76 +++++++++++++++++----------------------------- >> 1 file changed, 28 insertions(+), 48 deletions(-) >> >> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c >> index 43cb2e0..ec54644 100644 >> --- a/drivers/net/virtio_net.c >> +++ b/drivers/net/virtio_net.c >> @@ -388,49 +388,6 @@ static void virtnet_xdp_xmit(struct virtnet_info *vi, >> virtqueue_kick(sq->vq); >> } >> > > [...] > >> /* This happens when rx buffer size is underestimated */ >> @@ -598,8 +570,10 @@ static struct sk_buff *receive_mergeable(struct >> net_device *dev, >> if (unlikely(hdr->hdr.gso_type)) >> goto err_xdp; >> - act = do_xdp_prog(vi, rq, xdp_prog, >> - page_address(xdp_page) + offset, len); >> + data = page_address(xdp_page) + offset; >> + xdp.data = data + desc_room; >> + xdp.data_end = xdp.data + (len - vi->hdr_len); > > It looks desc_room is always vi->hdr_len. > Seems to be the case I'll just use vi->hdr_len and remove the variable. Thanks. >> + act = bpf_prog_run_xdp(xdp_prog, &xdp); >> switch (act) { >> case XDP_PASS: >> /* We can only create skb based on xdp_page. */ >> @@ -613,13 +587,19 @@ static struct sk_buff *receive_mergeable(struct >> net_device *dev, >> } >> break; >> case XDP_TX: >> + qp = vi->curr_queue_pairs - >> + vi->xdp_queue_pairs + >> + smp_processor_id(); >> + virtnet_xdp_xmit(vi, rq, &vi->sq[qp], &xdp, data); >> ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len); >> if (unlikely(xdp_page != page)) >> goto err_xdp; >> rcu_read_unlock(); >> goto xdp_xmit; >> - case XDP_DROP: >> default: >> + bpf_warn_invalid_xdp_action(act); >> + case XDP_ABORTED: >> + case XDP_DROP: >> if (unlikely(xdp_page != page)) >> __free_pages(xdp_page, 0); >> ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len); >> >