From dcdc8994697faa789669c3fdaca1a8bc27a8f356 Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Mon, 2 Feb 2015 16:07:34 -0800 Subject: [PATCH] net: add skb functions to process remote checksum offload This patch adds skb_remcsum_process and skb_gro_remcsum_process to perform the appropriate adjustments to the skb when receiving remote checksum offload. Updated vxlan and gue to use these functions. Tested: Ran TCP_RR and TCP_STREAM netperf for VXLAN and GUE, did not see any change in performance. Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- drivers/net/vxlan.c | 18 ++---------------- include/linux/netdevice.h | 15 +++++++++++++++ include/linux/skbuff.h | 21 +++++++++++++++++++++ net/ipv4/fou.c | 18 ++---------------- 4 files changed, 40 insertions(+), 32 deletions(-) diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 31bac2a21ce3..c184717e8b28 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -558,7 +558,6 @@ static struct vxlanhdr *vxlan_gro_remcsum(struct sk_buff *skb, u32 data) { size_t start, offset, plen; - __wsum delta; if (skb->remcsum_offload) return vh; @@ -580,12 +579,7 @@ static struct vxlanhdr *vxlan_gro_remcsum(struct sk_buff *skb, return NULL; } - delta = remcsum_adjust((void *)vh + hdrlen, - NAPI_GRO_CB(skb)->csum, start, offset); - - /* Adjust skb->csum since we changed the packet */ - skb->csum = csum_add(skb->csum, delta); - NAPI_GRO_CB(skb)->csum = csum_add(NAPI_GRO_CB(skb)->csum, delta); + skb_gro_remcsum_process(skb, (void *)vh + hdrlen, start, offset); skb->remcsum_offload = 1; @@ -1159,7 +1153,6 @@ static struct vxlanhdr *vxlan_remcsum(struct sk_buff *skb, struct vxlanhdr *vh, size_t hdrlen, u32 data) { size_t start, offset, plen; - __wsum delta; if (skb->remcsum_offload) { /* Already processed in GRO path */ @@ -1179,14 +1172,7 @@ static struct vxlanhdr *vxlan_remcsum(struct sk_buff *skb, struct vxlanhdr *vh, vh = (struct vxlanhdr *)(udp_hdr(skb) + 1); - if (unlikely(skb->ip_summed != CHECKSUM_COMPLETE)) - __skb_checksum_complete(skb); - - delta = remcsum_adjust((void *)vh + hdrlen, - skb->csum, start, offset); - - /* Adjust skb->csum since we changed the packet */ - skb->csum = csum_add(skb->csum, delta); + skb_remcsum_process(skb, (void *)vh + hdrlen, start, offset); return vh; } diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 16251e96e6aa..1347ac50d2af 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2318,6 +2318,21 @@ do { \ compute_pseudo(skb, proto)); \ } while (0) +static inline void skb_gro_remcsum_process(struct sk_buff *skb, void *ptr, + int start, int offset) +{ + __wsum delta; + + BUG_ON(!NAPI_GRO_CB(skb)->csum_valid); + + delta = remcsum_adjust(ptr, NAPI_GRO_CB(skb)->csum, start, offset); + + /* Adjust skb->csum since we changed the packet */ + skb->csum = csum_add(skb->csum, delta); + NAPI_GRO_CB(skb)->csum = csum_add(NAPI_GRO_CB(skb)->csum, delta); +} + + static inline int dev_hard_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 2748ff639144..5405dfe02572 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -3099,6 +3099,27 @@ do { \ compute_pseudo(skb, proto)); \ } while (0) +/* Update skbuf and packet to reflect the remote checksum offload operation. + * When called, ptr indicates the starting point for skb->csum when + * ip_summed is CHECKSUM_COMPLETE. If we need create checksum complete + * here, skb_postpull_rcsum is done so skb->csum start is ptr. + */ +static inline void skb_remcsum_process(struct sk_buff *skb, void *ptr, + int start, int offset) +{ + __wsum delta; + + if (unlikely(skb->ip_summed != CHECKSUM_COMPLETE)) { + __skb_checksum_complete(skb); + skb_postpull_rcsum(skb, skb->data, ptr - (void *)skb->data); + } + + delta = remcsum_adjust(ptr, skb->csum, start, offset); + + /* Adjust skb->csum since we changed the packet */ + skb->csum = csum_add(skb->csum, delta); +} + #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) void nf_conntrack_destroy(struct nf_conntrack *nfct); static inline void nf_conntrack_put(struct nf_conntrack *nfct) diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c index 3bc0cf07661c..92ddea1e6457 100644 --- a/net/ipv4/fou.c +++ b/net/ipv4/fou.c @@ -70,7 +70,6 @@ static struct guehdr *gue_remcsum(struct sk_buff *skb, struct guehdr *guehdr, size_t start = ntohs(pd[0]); size_t offset = ntohs(pd[1]); size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start); - __wsum delta; if (skb->remcsum_offload) { /* Already processed in GRO path */ @@ -82,14 +81,7 @@ static struct guehdr *gue_remcsum(struct sk_buff *skb, struct guehdr *guehdr, return NULL; guehdr = (struct guehdr *)&udp_hdr(skb)[1]; - if (unlikely(skb->ip_summed != CHECKSUM_COMPLETE)) - __skb_checksum_complete(skb); - - delta = remcsum_adjust((void *)guehdr + hdrlen, - skb->csum, start, offset); - - /* Adjust skb->csum since we changed the packet */ - skb->csum = csum_add(skb->csum, delta); + skb_remcsum_process(skb, (void *)guehdr + hdrlen, start, offset); return guehdr; } @@ -228,7 +220,6 @@ static struct guehdr *gue_gro_remcsum(struct sk_buff *skb, unsigned int off, size_t start = ntohs(pd[0]); size_t offset = ntohs(pd[1]); size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start); - __wsum delta; if (skb->remcsum_offload) return guehdr; @@ -243,12 +234,7 @@ static struct guehdr *gue_gro_remcsum(struct sk_buff *skb, unsigned int off, return NULL; } - delta = remcsum_adjust((void *)guehdr + hdrlen, - NAPI_GRO_CB(skb)->csum, start, offset); - - /* Adjust skb->csum since we changed the packet */ - skb->csum = csum_add(skb->csum, delta); - NAPI_GRO_CB(skb)->csum = csum_add(NAPI_GRO_CB(skb)->csum, delta); + skb_gro_remcsum_process(skb, (void *)guehdr + hdrlen, start, offset); skb->remcsum_offload = 1; -- 2.20.1