summaryrefslogtreecommitdiffstats
path: root/net/core
diff options
context:
space:
mode:
authorEric Dumazet <eric.dumazet@gmail.com>2011-11-28 20:30:35 +0000
committerDavid S. Miller <davem@davemloft.net>2011-11-29 13:17:03 -0500
commit4d77d2b567ec66a443792d99e96ac760991d80d0 (patch)
tree8724a150e73cf33fd8a2f36f2b2432af3a78a3e8 /net/core
parentc3940999b29ca7d6ad9b37b827a058c90fd51992 (diff)
flow_dissector: use a 64bit load/store
Le lundi 28 novembre 2011 à 19:06 -0500, David Miller a écrit : > From: Dimitris Michailidis <dm@chelsio.com> > Date: Mon, 28 Nov 2011 08:25:39 -0800 > > >> +bool skb_flow_dissect(const struct sk_buff *skb, struct flow_keys > >> *flow) > >> +{ > >> + int poff, nhoff = skb_network_offset(skb); > >> + u8 ip_proto; > >> + u16 proto = skb->protocol; > > > > __be16 instead of u16 for proto? > > I'll take care of this when I apply these patches. ( CC trimmed ) Thanks David ! Here is a small patch to use one 64bit load/store on x86_64 instead of two 32bit load/stores. [PATCH net-next] flow_dissector: use a 64bit load/store gcc compiler is smart enough to use a single load/store if we memcpy(dptr, sptr, 8) on x86_64, regardless of CONFIG_CC_OPTIMIZE_FOR_SIZE In IP header, daddr immediately follows saddr, this wont change in the future. We only need to make sure our flow_keys (src,dst) fields wont break the rule. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core')
-rw-r--r--net/core/flow_dissector.c13
1 files changed, 11 insertions, 2 deletions
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index f0516d9280c..0985b9b14b8 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -8,6 +8,16 @@
#include <linux/ppp_defs.h>
#include <net/flow_keys.h>
+/* copy saddr & daddr, possibly using 64bit load/store
+ * Equivalent to : flow->src = iph->saddr;
+ * flow->dst = iph->daddr;
+ */
+static void iph_to_flow_copy_addrs(struct flow_keys *flow, const struct iphdr *iph)
+{
+ BUILD_BUG_ON(offsetof(typeof(*flow), dst) !=
+ offsetof(typeof(*flow), src) + sizeof(flow->src));
+ memcpy(&flow->src, &iph->saddr, sizeof(flow->src) + sizeof(flow->dst));
+}
bool skb_flow_dissect(const struct sk_buff *skb, struct flow_keys *flow)
{
@@ -31,8 +41,7 @@ ip:
ip_proto = 0;
else
ip_proto = iph->protocol;
- flow->src = iph->saddr;
- flow->dst = iph->daddr;
+ iph_to_flow_copy_addrs(flow, iph);
nhoff += iph->ihl * 4;
break;
}