From ccad637b0c57de1825ffd34c311bf71487545ac2 Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Wed, 19 Nov 2008 22:42:31 -0800 Subject: netdev: expose ethernet address primitives When ethernet devices are converted, the function pointer setup by eth_setup() need to be done during intialization. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- net/ethernet/eth.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) (limited to 'net/ethernet/eth.c') diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c index b9d85af2dd31..a87a171d9914 100644 --- a/net/ethernet/eth.c +++ b/net/ethernet/eth.c @@ -282,7 +282,7 @@ EXPORT_SYMBOL(eth_header_cache_update); * This doesn't change hardware matching, so needs to be overridden * for most real devices. */ -static int eth_mac_addr(struct net_device *dev, void *p) +int eth_mac_addr(struct net_device *dev, void *p) { struct sockaddr *addr = p; @@ -293,6 +293,7 @@ static int eth_mac_addr(struct net_device *dev, void *p) memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN); return 0; } +EXPORT_SYMBOL(eth_mac_addr); /** * eth_change_mtu - set new MTU size @@ -302,21 +303,23 @@ static int eth_mac_addr(struct net_device *dev, void *p) * Allow changing MTU size. Needs to be overridden for devices * supporting jumbo frames. */ -static int eth_change_mtu(struct net_device *dev, int new_mtu) +int eth_change_mtu(struct net_device *dev, int new_mtu) { if (new_mtu < 68 || new_mtu > ETH_DATA_LEN) return -EINVAL; dev->mtu = new_mtu; return 0; } +EXPORT_SYMBOL(eth_change_mtu); -static int eth_validate_addr(struct net_device *dev) +int eth_validate_addr(struct net_device *dev) { if (!is_valid_ether_addr(dev->dev_addr)) return -EADDRNOTAVAIL; return 0; } +EXPORT_SYMBOL(eth_validate_addr); const struct header_ops eth_header_ops ____cacheline_aligned = { .create = eth_header, @@ -334,11 +337,11 @@ const struct header_ops eth_header_ops ____cacheline_aligned = { void ether_setup(struct net_device *dev) { dev->header_ops = ð_header_ops; - +#ifdef CONFIG_COMPAT_NET_DEV_OPS dev->change_mtu = eth_change_mtu; dev->set_mac_address = eth_mac_addr; dev->validate_addr = eth_validate_addr; - +#endif dev->type = ARPHRD_ETHER; dev->hard_header_len = ETH_HLEN; dev->mtu = ETH_DATA_LEN; -- cgit v1.2.3 From 1f87e235e6fb92c2968b52b9191de04f1aff8e77 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sun, 23 Nov 2008 23:24:32 -0800 Subject: eth: Declare an optimized compare_ether_addr_64bits() function Linus mentioned we could try to perform long word operations, even on potentially unaligned addresses, on x86 at least. David mentioned the HAVE_EFFICIENT_UNALIGNED_ACCESS test to handle this on all arches that have efficient unailgned accesses. I tried this idea and got nice assembly on 32 bits: 158: 33 82 38 01 00 00 xor 0x138(%edx),%eax 15e: 33 8a 34 01 00 00 xor 0x134(%edx),%ecx 164: c1 e0 10 shl $0x10,%eax 167: 09 c1 or %eax,%ecx 169: 74 0b je 176 And very nice assembly on 64 bits of course (one xor, one shl) Nice oprofile improvement in eth_type_trans(), 0.17 % instead of 0.41 %, expected since we remove 8 instructions on a fast path. This patch implements a compare_ether_addr_64bits() function, that uses the CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS ifdef to efficiently perform the 6 bytes comparison on all capable arches. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/linux/etherdevice.h | 42 ++++++++++++++++++++++++++++++++++++++++++ net/ethernet/eth.c | 6 +++--- 2 files changed, 45 insertions(+), 3 deletions(-) (limited to 'net/ethernet/eth.c') diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h index 0e5e97060034..1cb0f0b90926 100644 --- a/include/linux/etherdevice.h +++ b/include/linux/etherdevice.h @@ -27,6 +27,7 @@ #include #include #include +#include #ifdef __KERNEL__ extern __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev); @@ -140,6 +141,47 @@ static inline unsigned compare_ether_addr(const u8 *addr1, const u8 *addr2) BUILD_BUG_ON(ETH_ALEN != 6); return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) != 0; } + +static inline unsigned long zap_last_2bytes(unsigned long value) +{ +#ifdef __BIG_ENDIAN + return value >> 16; +#else + return value << 16; +#endif +} + +/** + * compare_ether_addr_64bits - Compare two Ethernet addresses + * @addr1: Pointer to an array of 8 bytes + * @addr2: Pointer to an other array of 8 bytes + * + * Compare two ethernet addresses, returns 0 if equal. + * Same result than "memcmp(addr1, addr2, ETH_ALEN)" but without conditional + * branches, and possibly long word memory accesses on CPU allowing cheap + * unaligned memory reads. + * arrays = { byte1, byte2, byte3, byte4, byte6, byte7, pad1, pad2} + * + * Please note that alignment of addr1 & addr2 is only guaranted to be 16 bits. + */ + +static inline unsigned compare_ether_addr_64bits(const u8 addr1[6+2], + const u8 addr2[6+2]) +{ +#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS + unsigned long fold = ((*(unsigned long *)addr1) ^ + (*(unsigned long *)addr2)); + + if (sizeof(fold) == 8) + return zap_last_2bytes(fold) != 0; + + fold |= zap_last_2bytes((*(unsigned long *)(addr1 + 4)) ^ + (*(unsigned long *)(addr2 + 4))); + return fold != 0; +#else + return compare_ether_addr(addr1, addr2); +#endif +} #endif /* __KERNEL__ */ #endif /* _LINUX_ETHERDEVICE_H */ diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c index a87a171d9914..280352aba403 100644 --- a/net/ethernet/eth.c +++ b/net/ethernet/eth.c @@ -165,8 +165,8 @@ __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev) skb_pull(skb, ETH_HLEN); eth = eth_hdr(skb); - if (is_multicast_ether_addr(eth->h_dest)) { - if (!compare_ether_addr(eth->h_dest, dev->broadcast)) + if (unlikely(is_multicast_ether_addr(eth->h_dest))) { + if (!compare_ether_addr_64bits(eth->h_dest, dev->broadcast)) skb->pkt_type = PACKET_BROADCAST; else skb->pkt_type = PACKET_MULTICAST; @@ -181,7 +181,7 @@ __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev) */ else if (1 /*dev->flags&IFF_PROMISC */ ) { - if (unlikely(compare_ether_addr(eth->h_dest, dev->dev_addr))) + if (unlikely(compare_ether_addr_64bits(eth->h_dest, dev->dev_addr))) skb->pkt_type = PACKET_OTHERHOST; } -- cgit v1.2.3