From d54385ce68cd18ab002b46f61246ad197cec92de Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Thu, 30 Apr 2015 14:53:54 -0700 Subject: [PATCH] etherdev: Process is_multicast_ether_addr at same size as other operations This change makes it so that we process the address in is_multicast_ether_addr at the same size as the other calls. This allows us to avoid duplicate reads when used with other calls such as is_zero_ether_addr or eth_addr_copy. In addition I have added a 64 bit version of the function so in eth_type_trans we can process the destination address as a 64 bit value throughout. Signed-off-by: Alexander Duyck Signed-off-by: David S. Miller --- include/linux/etherdevice.h | 24 +++++++++++++++++++++++- net/ethernet/eth.c | 2 +- 2 files changed, 24 insertions(+), 2 deletions(-) diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h index 606563ef8a72..c4a10f991fe0 100644 --- a/include/linux/etherdevice.h +++ b/include/linux/etherdevice.h @@ -110,7 +110,29 @@ static inline bool is_zero_ether_addr(const u8 *addr) */ static inline bool is_multicast_ether_addr(const u8 *addr) { - return 0x01 & addr[0]; +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) + u32 a = *(const u32 *)addr; +#else + u16 a = *(const u16 *)addr; +#endif +#ifdef __BIG_ENDIAN + return 0x01 & (a >> ((sizeof(a) * 8) - 8)); +#else + return 0x01 & a; +#endif +} + +static inline bool is_multicast_ether_addr_64bits(const u8 addr[6+2]) +{ +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 +#ifdef __BIG_ENDIAN + return 0x01 & ((*(const u64 *)addr) >> 56); +#else + return 0x01 & (*(const u64 *)addr); +#endif +#else + return is_multicast_ether_addr(addr); +#endif } /** diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c index 60069318d5d1..21c211e9fd5a 100644 --- a/net/ethernet/eth.c +++ b/net/ethernet/eth.c @@ -159,7 +159,7 @@ __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev) skb_pull_inline(skb, ETH_HLEN); eth = eth_hdr(skb); - if (unlikely(is_multicast_ether_addr(eth->h_dest))) { + if (unlikely(is_multicast_ether_addr_64bits(eth->h_dest))) { if (ether_addr_equal_64bits(eth->h_dest, dev->broadcast)) skb->pkt_type = PACKET_BROADCAST; else -- 2.20.1