From f663dd9aaf9ed124f25f0f8452edf238f087ad50 Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Fri, 10 Jan 2014 16:18:26 +0800 Subject: net: core: explicitly select a txq before doing l2 forwarding Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The will cause several issues: - NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan instead of lower device which misses the necessary txq synchronization for lower device such as txq stopping or frozen required by dev watchdog or control path. - dev_hard_start_xmit() was called with NULL txq which bypasses the net device watchdog. - dev_hard_start_xmit() does not check txq everywhere which will lead a crash when tso is disabled for lower device. Fix this by explicitly introducing a new param for .ndo_select_queue() for just selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also extended to accept this parameter and dev_queue_xmit_accel() was used to do l2 forwarding transmission. With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of dev_queue_xmit() to do the transmission. In the future, it was also required for macvtap l2 forwarding support since it provides a necessary synchronization method. Cc: John Fastabend Cc: Neil Horman Cc: e1000-devel@lists.sourceforge.net Signed-off-by: Jason Wang Acked-by: Neil Horman Acked-by: John Fastabend Signed-off-by: David S. Miller --- net/mac80211/iface.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'net/mac80211/iface.c') diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c index 36c3a4cbcabf..a0757913046e 100644 --- a/net/mac80211/iface.c +++ b/net/mac80211/iface.c @@ -1061,7 +1061,8 @@ static void ieee80211_uninit(struct net_device *dev) } static u16 ieee80211_netdev_select_queue(struct net_device *dev, - struct sk_buff *skb) + struct sk_buff *skb, + void *accel_priv) { return ieee80211_select_queue(IEEE80211_DEV_TO_SUB_IF(dev), skb); } @@ -1078,7 +1079,8 @@ static const struct net_device_ops ieee80211_dataif_ops = { }; static u16 ieee80211_monitor_select_queue(struct net_device *dev, - struct sk_buff *skb) + struct sk_buff *skb, + void *accel_priv) { struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); struct ieee80211_local *local = sdata->local; -- cgit v1.2.3