Re: [PATCHv2 net] sunvnet: set queue mapping when doing packet copies
From: Eric Dumazet <hidden>
Date: 2015-01-29 20:39:59
On Thu, 2015-01-29 at 14:42 -0500, David L Stevens wrote:
quoted hunk ↗ jump to hunk
This patch fixes a bug where vnet_skb_shape() didn't set the already-selected queue mapping when a packet copy was required. This results in using the wrong queue index for stops/starts, hung tx queues and watchdog timeouts under heavy load. It also transfers the destructor, truesize, and the owning socket for flow control (code adapted from skb_segment). Signed-off-by: David L Stevens <redacted> Acked-by: Sowmini Varadhan <redacted> -- Changes since v1: move truesize, destructor and socket per Eric Dumazet [off-list ref] --- drivers/net/ethernet/sun/sunvnet.c | 10 ++++++++++ 1 files changed, 10 insertions(+), 0 deletions(-)diff --git a/drivers/net/ethernet/sun/sunvnet.c b/drivers/net/ethernet/sun/sunvnet.c index 2b719cc..0a1d3eb 100644 --- a/drivers/net/ethernet/sun/sunvnet.c +++ b/drivers/net/ethernet/sun/sunvnet.c@@ -1123,6 +1123,16 @@ static inline struct sk_buff *vnet_skb_shape(struct sk_buff *skb, int ncookies) skb_shinfo(nskb)->gso_size = skb_shinfo(skb)->gso_size; skb_shinfo(nskb)->gso_type = skb_shinfo(skb)->gso_type; } + nskb->queue_mapping = skb->queue_mapping; + /* Following permits correct back-pressure, for protocols + * using skb_set_owner_w(). + * Idea is to transfer ownership from skb to nskb. + */ + if (skb->destructor == sock_wfree) {
Sorry, but you should remove this test. (TCP uses another destructor, not sock_wfree()) All sent packets will support these swap() operations, regardless of destructor.
+ swap(nskb->truesize, skb->truesize); + swap(nskb->destructor, skb->destructor); + swap(nskb->sk, skb->sk); + } dev_kfree_skb(skb); skb = nskb; }