@@ -3,6 +3,7 @@
#define _ARP_H
#include <linux/if_arp.h>
+#include <linux/hash.h>
#include <net/neighbour.h>
@@ -10,7 +11,7 @@ extern struct neigh_table arp_tbl;
static inline u32 arp_hashfn(u32 key, const struct net_device *dev, u32 hash_rnd)
{
- u32 val = key ^ dev->ifindex;
+ u32 val = key ^ ptr_hash_mix(dev);
return val * hash_rnd;
}
@@ -49,6 +49,7 @@ enum {
#include <linux/types.h>
#include <linux/if_arp.h>
#include <linux/netdevice.h>
+#include <linux/hash.h>
#include <net/neighbour.h>
@@ -134,7 +135,7 @@ static inline u32 ndisc_hashfn(const void *pkey, const struct net_device *dev, _
{
const u32 *p32 = pkey;
- return (((p32[0] ^ dev->ifindex) * hash_rnd[0]) +
+ return (((p32[0] ^ ptr_hash_mix(dev)) * hash_rnd[0]) +
(p32[1] * hash_rnd[1]) +
(p32[2] * hash_rnd[2]) +
(p32[3] * hash_rnd[3]));
Eric noticed, that when there will be devices with equal indices, some hash functions that use them will become less effective as they could. Fix this in advance by taking the net_device address into calculations instead of the device index. Since the net_device is always aligned in memory, shift the pointer to eliminate always zero bits (like we do it in net_hash_mix). This is true for arp and ndisc hash fns. The netlabel, can and llc ones are also ifindex-based, but that three are init_net-only, thus will not be affected. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> --- include/net/arp.h | 3 ++- include/net/ndisc.h | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-)