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 <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 2748ff6..5405dfe 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -3099,6 +3099,27 @@
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)