net: Revert "net: avoid one atomic operation in skb_clone()"

[firefly-linux-kernel-4.4.55.git] / net / core / skbuff.c

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 61059a05ec95f1fdc420e7bbb250d1a8b22c87b0..32e31c2996315770149b71b1e17837311d672a1e 100644 (file)
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -552,20 +552,13 @@ static void kfree_skbmem(struct sk_buff *skb)
        case SKB_FCLONE_CLONE:
                fclones = container_of(skb, struct sk_buff_fclones, skb2);
 
-               /* Warning : We must perform the atomic_dec_and_test() before
-                * setting skb->fclone back to SKB_FCLONE_FREE, otherwise
-                * skb_clone() could set clone_ref to 2 before our decrement.
-                * Anyway, if we are going to free the structure, no need to
-                * rewrite skb->fclone.
+               /* The clone portion is available for
+                * fast-cloning again.
                 */
-               if (atomic_dec_and_test(&fclones->fclone_ref)) {
+               skb->fclone = SKB_FCLONE_FREE;
+
+               if (atomic_dec_and_test(&fclones->fclone_ref))
                        kmem_cache_free(skbuff_fclone_cache, fclones);
-               } else {
-                       /* The clone portion is available for
-                        * fast-cloning again.
-                        */
-                       skb->fclone = SKB_FCLONE_FREE;
-               }
                break;
        }
 }
@@ -887,11 +880,7 @@ struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t gfp_mask)
        if (skb->fclone == SKB_FCLONE_ORIG &&
            n->fclone == SKB_FCLONE_FREE) {
                n->fclone = SKB_FCLONE_CLONE;
-               /* As our fastclone was free, clone_ref must be 1 at this point.
-                * We could use atomic_inc() here, but it is faster
-                * to set the final value.
-                */
-               atomic_set(&fclones->fclone_ref, 2);
+               atomic_inc(&fclones->fclone_ref);
        } else {
                if (skb_pfmemalloc(skb))
                        gfp_mask |= __GFP_MEMALLOC;
@@ -4070,15 +4059,22 @@ EXPORT_SYMBOL_GPL(skb_scrub_packet);
 unsigned int skb_gso_transport_seglen(const struct sk_buff *skb)
 {
        const struct skb_shared_info *shinfo = skb_shinfo(skb);
+       unsigned int thlen = 0;
 
-       if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
-               return tcp_hdrlen(skb) + shinfo->gso_size;
+       if (skb->encapsulation) {
+               thlen = skb_inner_transport_header(skb) -
+                       skb_transport_header(skb);
 
+               if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
+                       thlen += inner_tcp_hdrlen(skb);
+       } else if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) {
+               thlen = tcp_hdrlen(skb);
+       }
        /* UFO sets gso_size to the size of the fragmentation
         * payload, i.e. the size of the L4 (UDP) header is already
         * accounted for.
         */
-       return shinfo->gso_size;
+       return thlen + shinfo->gso_size;
 }
 EXPORT_SYMBOL_GPL(skb_gso_transport_seglen);