From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jesper Dangaard Brouer Subject: Re: [PATCH] netdev: pktgen xmit packet through vlan interface Date: Fri, 2 May 2014 15:19:21 +0200 Message-ID: <20140502151921.014fbeec@redhat.com> References: <1399015092-28643-1-git-send-email-zhouzhouyi@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: brouer@redhat.com, , , , , , , , , Zhouyi Zhou To: Zhouyi Zhou Return-path: In-Reply-To: <1399015092-28643-1-git-send-email-zhouzhouyi@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Fri, 2 May 2014 15:18:12 +0800 Zhouyi Zhou wrote: > As http://www.spinics.net/lists/netdev/msg165015.html > pktgen generates shared packet through vlan interface will cause > oops because of duplicate entering tc queue. > > Try to solve this problem by means of packet clone instead of sharing. I really don't like adding this stuff to the fast path of pktgen. Why would you use pktgen on a VLAN? Why don't you use the "vlan_id" feature available in pktgen, and send in the lower real device? > Signed-off-by: Zhouyi Zhou > --- > net/core/pktgen.c | 20 +++++++++++++++++--- > 1 files changed, 17 insertions(+), 3 deletions(-) > > diff --git a/net/core/pktgen.c b/net/core/pktgen.c > index 0304f98..ced07fc 100644 > --- a/net/core/pktgen.c > +++ b/net/core/pktgen.c > @@ -3297,6 +3297,7 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev) > netdev_tx_t (*xmit)(struct sk_buff *, struct net_device *) > = odev->netdev_ops->ndo_start_xmit; > struct netdev_queue *txq; > + struct sk_buff *nskb = NULL; > u16 queue_map; > int ret; > > @@ -3347,8 +3348,18 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev) > pkt_dev->last_ok = 0; > goto unlock; > } > - atomic_inc(&(pkt_dev->skb->users)); > - ret = (*xmit)(pkt_dev->skb, odev); > + > + if (pkt_dev->clone_skb && is_vlan_dev(odev)) { > + nskb = skb_clone(pkt_dev->skb, GFP_ATOMIC); > + ret = -ENOMEM; > + if (nskb) > + ret = (*xmit)(nskb, odev); > + else > + nskb = ERR_PTR(ret); > + } else { > + atomic_inc(&(pkt_dev->skb->users)); > + ret = (*xmit)(pkt_dev->skb, odev); > + } > > switch (ret) { > case NETDEV_TX_OK: > @@ -3372,7 +3383,10 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev) > case NETDEV_TX_LOCKED: > case NETDEV_TX_BUSY: > /* Retry it next time */ > - atomic_dec(&(pkt_dev->skb->users)); > + if (nskb && !IS_ERR(nskb)) > + kfree_skb(nskb); > + else > + atomic_dec(&(pkt_dev->skb->users)); > pkt_dev->last_ok = 0; > } > unlock: -- Best regards, Jesper Dangaard Brouer MSc.CS, Sr. Network Kernel Developer at Red Hat Author of http://www.iptv-analyzer.org LinkedIn: http://www.linkedin.com/in/brouer