From 3b392ddba25a95dcf5fb30b33358961c49dd5cfc Mon Sep 17 00:00:00 2001 From: Simon Horman Date: Wed, 4 Jun 2014 08:53:17 +0900 Subject: MPLS: Use mpls_features to activate software MPLS GSO segmentation If an MPLS packet requires segmentation then use mpls_features to determine if the software implementation should be used. As no driver advertises MPLS GSO segmentation this will always be the case. I had not noticed that this was necessary before as software MPLS GSO segmentation was already being used in my test environment. I believe that the reason for that is the skbs in question always had fragments and the driver I used does not advertise NETIF_F_FRAGLIST (which seems to be the case for most drivers). Thus software segmentation was activated by skb_gso_ok(). This introduces the overhead of an extra call to skb_network_protocol() in the case where where CONFIG_NET_MPLS_GSO is set and skb->ip_summed == CHECKSUM_NONE. Thanks to Jesse Gross for prompting me to investigate this. Signed-off-by: Simon Horman Acked-by: YAMAMOTO Takashi Acked-by: Thomas Graf Signed-off-by: David S. Miller --- net/core/dev.c | 28 +++++++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/core/dev.c b/net/core/dev.c index a9a08e4a4857..ed8fe62d41af 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2513,13 +2513,39 @@ static int dev_gso_segment(struct sk_buff *skb, netdev_features_t features) return 0; } +/* If MPLS offload request, verify we are testing hardware MPLS features + * instead of standard features for the netdev. + */ +#ifdef CONFIG_NET_MPLS_GSO +static netdev_features_t net_mpls_features(struct sk_buff *skb, + netdev_features_t features, + __be16 type) +{ + if (type == htons(ETH_P_MPLS_UC) || type == htons(ETH_P_MPLS_MC)) + features &= skb->dev->mpls_features; + + return features; +} +#else +static netdev_features_t net_mpls_features(struct sk_buff *skb, + netdev_features_t features, + __be16 type) +{ + return features; +} +#endif + static netdev_features_t harmonize_features(struct sk_buff *skb, netdev_features_t features) { int tmp; + __be16 type; + + type = skb_network_protocol(skb, &tmp); + features = net_mpls_features(skb, features, type); if (skb->ip_summed != CHECKSUM_NONE && - !can_checksum_protocol(features, skb_network_protocol(skb, &tmp))) { + !can_checksum_protocol(features, type)) { features &= ~NETIF_F_ALL_CSUM; } else if (illegal_highdma(skb->dev, skb)) { features &= ~NETIF_F_SG; -- cgit v1.2.3