Re: [PATCH net-next v4 0/5] net: introduce and use route hint

[Edward Cree <ecree@solarflare.com>]

On 20/11/2019 12:47, Paolo Abeni wrote:
> This series leverages the listification infrastructure to avoid
> unnecessary route lookup on ingress packets. In absence of custom rules,
> packets with equal daddr will usually land on the same dst.
>
> When processing packet bursts (lists) we can easily reference the previous
> dst entry. When we hit the 'same destination' condition we can avoid the
> route lookup, coping the already available dst.
>
> Detailed performance numbers are available in the individual commit
> messages.
I wonder if you could use static keys for the fib*_has_custom_rules()
 and if that would gain you any extra speed?
Other than that,
Acked-by: Edward Cree <ecree@solarflare.com>
 for the series.
>
> v3 -> v4:
>  - move helpers to their own patches (Eric D.)
>  - enable hints for SUBTREE builds (David A.)
>  - re-enable hints for ipv4 forward (David A.)
>
> v2 -> v3:
>  - use fib*_has_custom_rules() helpers (David A.)
>  - add ip*_extract_route_hint() helper (Edward C.)
>  - use prev skb as hint instead of copying data (Willem )
>
> v1 -> v2:
>  - fix build issue with !CONFIG_IP*_MULTIPLE_TABLES
>  - fix potential race in ip6_list_rcv_finish()
>
> Paolo Abeni (5):
>   ipv6: add fib6_has_custom_rules() helper
>   ipv6: keep track of routes using src
>   ipv6: introduce and uses route look hints for list input.
>   ipv4: move fib4_has_custom_rules() helper to public header
>   ipv4: use dst hint for ipv4 list receive
>
>  include/net/ip6_fib.h    | 39 +++++++++++++++++++++++++++++++++++++
>  include/net/ip_fib.h     | 10 ++++++++++
>  include/net/netns/ipv6.h |  3 +++
>  include/net/route.h      |  4 ++++
>  net/ipv4/fib_frontend.c  | 10 ----------
>  net/ipv4/ip_input.c      | 35 +++++++++++++++++++++++++++++----
>  net/ipv4/route.c         | 42 ++++++++++++++++++++++++++++++++++++++++
>  net/ipv6/ip6_fib.c       |  4 ++++
>  net/ipv6/ip6_input.c     | 26 +++++++++++++++++++++++--
>  net/ipv6/route.c         |  3 +++
>  10 files changed, 160 insertions(+), 16 deletions(-)
>