Re: [PATCH net-next 0/4] ipv6: Add support for non-equal-cost multipath

[David Ahern <dsahern@gmail.com>]

On 1/9/18 7:40 AM, Ido Schimmel wrote:
> This set aims to add support for IPv6 non-equal-cost multipath routes.
> The first three patches convert multipath selection to use the
> hash-threshold method (RFC 2992) instead of modulo-N. The same method is
> employed by the IPv4 routing code since commit 0e884c78ee19 ("ipv4: L3
> hash-based multipath").
> 
> Unlike modulo-N, with hash-threshold only the flows near the region
> boundaries are affected when a nexthop is added or removed. In addition,
> it allows us to easily add support for non-equal-cost multipath in the
> last patch by sizing the different regions according to the provided
> weights.
> 
> Ido Schimmel (4):
>   ipv6: Calculate hash thresholds for IPv6 nexthops
>   ipv6: Use a 31-bit multipath hash
>   ipv6: Use hash-threshold instead of modulo-N
>   ipv6: Add support for non-equal-cost multipath
> 
>  include/net/ip6_fib.h   |   2 +
>  include/net/ip6_route.h |   7 +++
>  net/ipv6/ip6_fib.c      |   8 +--
>  net/ipv6/route.c        | 141 +++++++++++++++++++++++++++++++++++++++---------
>  4 files changed, 126 insertions(+), 32 deletions(-)
> 

Also, have you considered support for sysctl_fib_multipath_hash_policy?