diff options
| author |   Eric Dumazet <edumazet@google.com> | 2018-03-31 12:59:00 -0700 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2018-03-31 23:25:40 -0400 |
| commit | f2d1c724fca176ddbd32a9397df49221afbcb227 (patch) | |
| tree | fd2adc5d5bf77f50ac9f50e126e5b39695bd4427 | |
| parent | ipv6: frags: get rid of ip6frag_skb_cb/FRAG6_CB (diff) | |
| download | linux-dev-f2d1c724fca176ddbd32a9397df49221afbcb227.tar.xz linux-dev-f2d1c724fca176ddbd32a9397df49221afbcb227.zip | |
inet: frags: get rid of nf_ct_frag6_skb_cb/NFCT_FRAG6_CB
nf_ct_frag6_queue() uses skb->cb[] to store the fragment offset,
meaning that we could use two cache lines per skb when finding
the insertion point, if for some reason inet6_skb_parm size
is increased in the future.
By using skb->ip_defrag_offset instead of skb->cb[] we pack all the fields
in a single cache line, matching what we did for IPv4.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv6/netfilter/nf_conntrack_reasm.c | 29 |
1 files changed, 11 insertions, 18 deletions
diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c index 603a39592859..3622aac343ae 100644 --- a/net/ipv6/netfilter/nf_conntrack_reasm.c +++ b/net/ipv6/netfilter/nf_conntrack_reasm.c @@ -52,14 +52,6 @@ static const char nf_frags_cache_name[] = "nf-frags"; -struct nf_ct_frag6_skb_cb -{ - struct inet6_skb_parm h; - int offset; -}; - -#define NFCT_FRAG6_CB(skb) ((struct nf_ct_frag6_skb_cb *)((skb)->cb)) - static struct inet_frags nf_frags; #ifdef CONFIG_SYSCTL @@ -270,13 +262,13 @@ static int nf_ct_frag6_queue(struct frag_queue *fq, struct sk_buff *skb, * this fragment, right? */ prev = fq->q.fragments_tail; - if (!prev || NFCT_FRAG6_CB(prev)->offset < offset) { + if (!prev || prev->ip_defrag_offset < offset) { next = NULL; goto found; } prev = NULL; for (next = fq->q.fragments; next != NULL; next = next->next) { - if (NFCT_FRAG6_CB(next)->offset >= offset) + if (next->ip_defrag_offset >= offset) break; /* bingo! */ prev = next; } @@ -292,14 +284,19 @@ found: /* Check for overlap with preceding fragment. */ if (prev && - (NFCT_FRAG6_CB(prev)->offset + prev->len) > offset) + (prev->ip_defrag_offset + prev->len) > offset) goto discard_fq; /* Look for overlap with succeeding segment. */ - if (next && NFCT_FRAG6_CB(next)->offset < end) + if (next && next->ip_defrag_offset < end) goto discard_fq; - NFCT_FRAG6_CB(skb)->offset = offset; + /* Note : skb->ip_defrag_offset and skb->dev share the same location */ + if (skb->dev) + fq->iif = skb->dev->ifindex; + /* Makes sure compiler wont do silly aliasing games */ + barrier(); + skb->ip_defrag_offset = offset; /* Insert this fragment in the chain of fragments. */ skb->next = next; @@ -310,10 +307,6 @@ found: else fq->q.fragments = skb; - if (skb->dev) { - fq->iif = skb->dev->ifindex; - skb->dev = NULL; - } fq->q.stamp = skb->tstamp; fq->q.meat += skb->len; fq->ecn |= ecn; @@ -357,7 +350,7 @@ nf_ct_frag6_reasm(struct frag_queue *fq, struct sk_buff *prev, struct net_devic inet_frag_kill(&fq->q); WARN_ON(head == NULL); - WARN_ON(NFCT_FRAG6_CB(head)->offset != 0); + WARN_ON(head->ip_defrag_offset != 0); ecn = ip_frag_ecn_table[fq->ecn]; if (unlikely(ecn == 0xff)) |