Commit 3e453ca1 authored by Petr Machata's avatar Petr Machata Committed by Jakub Kicinski
Browse files

net: ipv4,ipv6: Pass multipath hash computation through a helper 



The following patches will add a sysctl to control multipath hash
seed. In order to centralize the hash computation, add a helper,
fib_multipath_hash_from_keys(), and have all IPv4 and IPv6 route.c
invocations of flow_hash_from_keys() go through this helper instead.

Signed-off-by: default avatarPetr Machata <petrm@nvidia.com>
Reviewed-by: default avatarIdo Schimmel <idosch@nvidia.com>
Reviewed-by: default avatarNikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: default avatarDavid Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240607151357.421181-2-petrm@nvidia.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 32b06603

include/net/ip_fib.h

+7 −0
Original line number Diff line number Diff line
@@ -521,6 +521,13 @@ void fib_nhc_update_mtu(struct fib_nh_common *nhc, u32 new, u32 orig); 
int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,

		       const struct sk_buff *skb, struct flow_keys *flkeys);

#endif



static inline u32 fib_multipath_hash_from_keys(const struct net *net,

					       struct flow_keys *keys)

{

	return flow_hash_from_keys(keys);

}



int fib_check_nh(struct net *net, struct fib_nh *nh, u32 table, u8 scope,

		 struct netlink_ext_ack *extack);

void fib_select_multipath(struct fib_result *res, int hash);

net/ipv4/route.c

+6 −6
Original line number Diff line number Diff line
@@ -1923,7 +1923,7 @@ static u32 fib_multipath_custom_hash_outer(const struct net *net, 
		hash_keys.ports.dst = keys.ports.dst;



	*p_has_inner = !!(keys.control.flags & FLOW_DIS_ENCAPSULATION);

	return flow_hash_from_keys(&hash_keys);

	return fib_multipath_hash_from_keys(net, &hash_keys);

}



static u32 fib_multipath_custom_hash_inner(const struct net *net,
@@ -1972,7 +1972,7 @@ static u32 fib_multipath_custom_hash_inner(const struct net *net, 
	if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT)

		hash_keys.ports.dst = keys.ports.dst;



	return flow_hash_from_keys(&hash_keys);

	return fib_multipath_hash_from_keys(net, &hash_keys);

}



static u32 fib_multipath_custom_hash_skb(const struct net *net,
@@ -2009,7 +2009,7 @@ static u32 fib_multipath_custom_hash_fl4(const struct net *net, 
	if (hash_fields & FIB_MULTIPATH_HASH_FIELD_DST_PORT)

		hash_keys.ports.dst = fl4->fl4_dport;



	return flow_hash_from_keys(&hash_keys);

	return fib_multipath_hash_from_keys(net, &hash_keys);

}



/* if skb is set it will be used and fl4 can be NULL */
@@ -2030,7 +2030,7 @@ int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4, 
			hash_keys.addrs.v4addrs.src = fl4->saddr;

			hash_keys.addrs.v4addrs.dst = fl4->daddr;

		}

		mhash = flow_hash_from_keys(&hash_keys);

		mhash = fib_multipath_hash_from_keys(net, &hash_keys);

		break;

	case 1:

		/* skb is currently provided only when forwarding */
@@ -2064,7 +2064,7 @@ int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4, 
			hash_keys.ports.dst = fl4->fl4_dport;

			hash_keys.basic.ip_proto = fl4->flowi4_proto;

		}

		mhash = flow_hash_from_keys(&hash_keys);

		mhash = fib_multipath_hash_from_keys(net, &hash_keys);

		break;

	case 2:

		memset(&hash_keys, 0, sizeof(hash_keys));
@@ -2095,7 +2095,7 @@ int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4, 
			hash_keys.addrs.v4addrs.src = fl4->saddr;

			hash_keys.addrs.v4addrs.dst = fl4->daddr;

		}

		mhash = flow_hash_from_keys(&hash_keys);

		mhash = fib_multipath_hash_from_keys(net, &hash_keys);

		break;

	case 3:

		if (skb)

net/ipv6/route.c

+6 −6
Original line number Diff line number Diff line
@@ -2372,7 +2372,7 @@ static u32 rt6_multipath_custom_hash_outer(const struct net *net, 
		hash_keys.ports.dst = keys.ports.dst;



	*p_has_inner = !!(keys.control.flags & FLOW_DIS_ENCAPSULATION);

	return flow_hash_from_keys(&hash_keys);

	return fib_multipath_hash_from_keys(net, &hash_keys);

}



static u32 rt6_multipath_custom_hash_inner(const struct net *net,
@@ -2421,7 +2421,7 @@ static u32 rt6_multipath_custom_hash_inner(const struct net *net, 
	if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT)

		hash_keys.ports.dst = keys.ports.dst;



	return flow_hash_from_keys(&hash_keys);

	return fib_multipath_hash_from_keys(net, &hash_keys);

}



static u32 rt6_multipath_custom_hash_skb(const struct net *net,
@@ -2460,7 +2460,7 @@ static u32 rt6_multipath_custom_hash_fl6(const struct net *net, 
	if (hash_fields & FIB_MULTIPATH_HASH_FIELD_DST_PORT)

		hash_keys.ports.dst = fl6->fl6_dport;



	return flow_hash_from_keys(&hash_keys);

	return fib_multipath_hash_from_keys(net, &hash_keys);

}



/* if skb is set it will be used and fl6 can be NULL */
@@ -2482,7 +2482,7 @@ u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6, 
			hash_keys.tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);

			hash_keys.basic.ip_proto = fl6->flowi6_proto;

		}

		mhash = flow_hash_from_keys(&hash_keys);

		mhash = fib_multipath_hash_from_keys(net, &hash_keys);

		break;

	case 1:

		if (skb) {
@@ -2514,7 +2514,7 @@ u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6, 
			hash_keys.ports.dst = fl6->fl6_dport;

			hash_keys.basic.ip_proto = fl6->flowi6_proto;

		}

		mhash = flow_hash_from_keys(&hash_keys);

		mhash = fib_multipath_hash_from_keys(net, &hash_keys);

		break;

	case 2:

		memset(&hash_keys, 0, sizeof(hash_keys));
@@ -2551,7 +2551,7 @@ u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6, 
			hash_keys.tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);

			hash_keys.basic.ip_proto = fl6->flowi6_proto;

		}

		mhash = flow_hash_from_keys(&hash_keys);

		mhash = fib_multipath_hash_from_keys(net, &hash_keys);

		break;

	case 3:

		if (skb)