On 5/2/2014 6:19 AM, Jesper Dangaard Brouer wrote:
On Fri, 2 May 2014 15:18:12 +0800
Zhouyi Zhou <zhouzho...@gmail.com> 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?
Its a good way to test qdiscs. When you run pktgen over the VLAN
you exercise the lower devices qdisc.
Although I never submitted a patch like this because I figured it
was a corner case and we would want to keep the hotpath clean.
Why don't you use the "vlan_id" feature available in pktgen, and send
in the lower real device?
Signed-off-by: Zhouyi Zhou <yizhouz...@ict.ac.cn>
---
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:
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
