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[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 <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Stephen Hemminger 2007-03-12 16:25:32 -07:00 committed by David S. Miller
parent eddc9ec53b
commit fd74e6ccd5
1 changed files with 5 additions and 1 deletions
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6
net/bridge/br_input.c
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@ -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;
}
/*