---

yaml
---
r: 122111
b: refs/heads/master
c: 1f87e23
h: refs/heads/master
i:
  122109: da88faf
  122107: 37c20c1
  122103: e52806d
  122095: b8f31df
  122079: 979dd2a
  122047: ad15cc6
  121983: 52baa54
  121855: 189b7f7
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 70eb1bfd52e97120eddf9b5aaabfe1ecdf4eb663
+refs/heads/master: 1f87e235e6fb92c2968b52b9191de04f1aff8e77

trunk/include/linux/etherdevice.h

@@ -27,6 +27,7 @@
 #include <linux/if_ether.h>
 #include <linux/netdevice.h>
 #include <linux/random.h>
+#include <asm/unaligned.h>
 
 #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 */

trunk/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;
 	}