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| author | Stephen Hemminger <shemminger@linux-foundation.org> | 2007-03-12 16:25:32 -0700 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2007-04-25 22:25:11 -0700 |
| commit | fd74e6ccd522e2f26163eb5ac1abebcab2bd017c (patch) | |
| tree | 12908a8736012d0c7203724c90139615dc221143 /net/bridge/br_input.c | |
| parent | eddc9ec53be2ecdbf4efe0efd4a83052594f0ac0 (diff) | |
| download | blackbird-op-linux-fd74e6ccd522e2f26163eb5ac1abebcab2bd017c.tar.gz blackbird-op-linux-fd74e6ccd522e2f26163eb5ac1abebcab2bd017c.zip | |
[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>
Diffstat (limited to 'net/bridge/br_input.c')
| -rw-r--r-- | net/bridge/br_input.c | 6 |
1 files changed, 5 insertions, 1 deletions
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; } /* |
