Merge branch 'net-ipv6-Add-support-for-path-selection-using-hash-of-5-tuple'

David Ahern says:

====================
net/ipv6: Add support for path selection using hash of 5-tuple

Hardware supports multipath selection using the standard L4 5-tuple
instead of just L3 and the flow label. In addition, some network
operators prefer IPv6 path selection to use the 5-tuple. To that end,
add support to IPv6 for multipath hash policy similar to
bf4e0a3db97eb ("net: ipv4: add support for ECMP hash policy choice").
The default is still L3 which covers source and destination addresses
along with flow label and IPv6 protocol. This gives users a choice in
hash algorithms if they believe L3 only and the IPv6 flow label are not
sufficient for their use case.

A separate sysctl is added for IPv6, allowing IPv4 and IPv6 to use
different algorithms if desired.

The first 3 patches modify the IPv4 variant so that at the end of the
patch set the ipv4 and ipv6 implementations are direct parallels.

Patch 4 refactors the existing rt6_multipath_hash in preparation for
adding the policy option.

Patch 5 renames the existing netevent to have IPv4 in the name so ipv4
changes can be distinguished from IPv6 if the netevent handler cares.

Patch 6 adds the skb as an argument through the FIB lookup functions
to the multipath selection. Needed for the forwarding case.

Patch 7 adds the L4 hash support.

Patch 8 adds the hook for the netevent to the spectrum driver to update
the ASIC.

Patch 9 removes no longer used code.

Patch 10 adds a testcase for IPv6 multipath with L4 hash.

v3
- comments from Ido:
  - removed fib_info arg in patch 1; left by mistake on rebase to net-next
  - removed __get_hash_from_flowi4 declaration
  - line wrap change to spectrum_router.c to maintain 80 chars

v2
- rebased to top of tree
- added refactor of fib_multipath_hash following recent change
- plumb skb through lookup functions to multipath selection
- fix sysctl setting; was missing the data set in ipv6_sysctl_net_init
- added test case

RFC to v1:
- rebase to top of net-next
- fix addr_type in hash_keys and removed flow label as noticed by Ido
- added a comment to cover letter about choice in algorithms based on
  use case per Or's comments
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 44 insertions, 0 deletions

diff --git a/tools/testing/selftests/net/forwarding/router_multipath.sh b/tools/testing/selftests/net/forwarding/router_multipath.sh
index 55595305a604..3bc351008db6 100755
--- a/tools/testing/selftests/net/forwarding/router_multipath.sh
+++ b/tools/testing/selftests/net/forwarding/router_multipath.sh
@@ -235,6 +235,45 @@ multipath4_test()
        sysctl -q -w net.ipv4.fib_multipath_hash_policy=$hash_policy
 }
 
+multipath6_l4_test()
+{
+       local desc="$1"
+       local weight_rp12=$2
+       local weight_rp13=$3
+       local t0_rp12 t0_rp13 t1_rp12 t1_rp13
+       local packets_rp12 packets_rp13
+       local hash_policy
+
+       # Transmit multiple flows from h1 to h2 and make sure they are
+       # distributed between both multipath links (rp12 and rp13)
+       # according to the configured weights.
+       hash_policy=$(sysctl -n net.ipv6.fib_multipath_hash_policy)
+       sysctl -q -w net.ipv6.fib_multipath_hash_policy=1
+
+       ip route replace 2001:db8:2::/64 vrf vrf-r1 \
+	       nexthop via fe80:2::22 dev $rp12 weight $weight_rp12 \
+	       nexthop via fe80:3::23 dev $rp13 weight $weight_rp13
+
+       t0_rp12=$(link_stats_tx_packets_get $rp12)
+       t0_rp13=$(link_stats_tx_packets_get $rp13)
+
+       $MZ $h1 -6 -q -p 64 -A 2001:db8:1::2 -B 2001:db8:2::2 \
+	       -d 1msec -t udp "sp=1024,dp=0-32768"
+
+       t1_rp12=$(link_stats_tx_packets_get $rp12)
+       t1_rp13=$(link_stats_tx_packets_get $rp13)
+
+       let "packets_rp12 = $t1_rp12 - $t0_rp12"
+       let "packets_rp13 = $t1_rp13 - $t0_rp13"
+       multipath_eval "$desc" $weight_rp12 $weight_rp13 $packets_rp12 $packets_rp13
+
+       ip route replace 2001:db8:2::/64 vrf vrf-r1 \
+	       nexthop via fe80:2::22 dev $rp12 \
+	       nexthop via fe80:3::23 dev $rp13
+
+       sysctl -q -w net.ipv6.fib_multipath_hash_policy=$hash_policy
+}
+
 multipath6_test()
 {
        local desc="$1"
@@ -278,6 +317,11 @@ multipath_test()
 	multipath6_test "ECMP" 1 1
 	multipath6_test "Weighted MP 2:1" 2 1
 	multipath6_test "Weighted MP 11:45" 11 45
+
+	log_info "Running IPv6 L4 hash multipath tests"
+	multipath6_l4_test "ECMP" 1 1
+	multipath6_l4_test "Weighted MP 2:1" 2 1
+	multipath6_l4_test "Weighted MP 11:45" 11 45
 }
 
 setup_prepare()