From fd74e6ccd522e2f26163eb5ac1abebcab2bd017c Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Mon, 12 Mar 2007 16:25:32 -0700 Subject: [BRIDGE]: faster compare for link local addresses Use logic operations rather than memcmp() to compare destination address with link local multicast addresses. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- net/bridge/br_input.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c index 35b94f9a1ac5..a260679afad8 100644 --- a/net/bridge/br_input.c +++ b/net/bridge/br_input.c @@ -112,7 +112,11 @@ static int br_handle_local_finish(struct sk_buff *skb) */ static inline int is_link_local(const unsigned char *dest) { - return memcmp(dest, br_group_address, 5) == 0 && (dest[5] & 0xf0) == 0; + const u16 *a = (const u16 *) dest; + static const u16 *const b = (const u16 *const ) br_group_address; + static const u16 m = __constant_cpu_to_be16(0xfff0); + + return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | ((a[2] ^ b[2]) & m)) == 0; } /* -- cgit v1.2.3