| Message ID | 20230825090830.18635-3-sriram.yagnaraman@est.tech (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | Avoid TCP resets when using ECMP for load-balancing between multiple servers. | expand |
On Fri, Aug 25, 2023 at 11:08:29AM +0200, Sriram Yagnaraman wrote: > diff --git a/net/ipv6/route.c b/net/ipv6/route.c > index 56a55585eb79..4631e03c84b4 100644 > --- a/net/ipv6/route.c > +++ b/net/ipv6/route.c > @@ -424,6 +424,8 @@ void fib6_select_path(const struct net *net, struct fib6_result *res, > if (match->nh && have_oif_match && res->nh) > return; > > + IP6CB(skb)->flags |= IP6SKB_MULTIPATH; skb can be NULL here in case this is called as part of route query from user space, so we need: diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 4631e03c84b4..a02328c93a53 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -424,7 +424,8 @@ void fib6_select_path(const struct net *net, struct fib6_result *res, if (match->nh && have_oif_match && res->nh) return; - IP6CB(skb)->flags |= IP6SKB_MULTIPATH; + if (skb) + IP6CB(skb)->flags |= IP6SKB_MULTIPATH; /* We might have already computed the hash for ICMPv6 errors. In such * case it will always be non-zero. Otherwise now is the time to do it.
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h index 839247a4f48e..fe3492a67b35 100644 --- a/include/linux/ipv6.h +++ b/include/linux/ipv6.h @@ -146,6 +146,7 @@ struct inet6_skb_parm { #define IP6SKB_JUMBOGRAM 128 #define IP6SKB_SEG6 256 #define IP6SKB_FAKEJUMBO 512 +#define IP6SKB_MULTIPATH 1024 }; #if defined(CONFIG_NET_L3_MASTER_DEV) diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c index d94041bb4287..b8378814532c 100644 --- a/net/ipv6/ip6_input.c +++ b/net/ipv6/ip6_input.c @@ -99,7 +99,8 @@ static bool ip6_can_use_hint(const struct sk_buff *skb, static struct sk_buff *ip6_extract_route_hint(const struct net *net, struct sk_buff *skb) { - if (fib6_routes_require_src(net) || fib6_has_custom_rules(net)) + if (fib6_routes_require_src(net) || fib6_has_custom_rules(net) || + IP6CB(skb)->flags & IP6SKB_MULTIPATH) return NULL; return skb; diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 56a55585eb79..4631e03c84b4 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -424,6 +424,8 @@ void fib6_select_path(const struct net *net, struct fib6_result *res, if (match->nh && have_oif_match && res->nh) return; + IP6CB(skb)->flags |= IP6SKB_MULTIPATH; + /* We might have already computed the hash for ICMPv6 errors. In such * case it will always be non-zero. Otherwise now is the time to do it. */
Route hints when the nexthop is part of a multipath group causes packets in the same receive batch to be sent to the same nexthop irrespective of the multipath hash of the packet. So, do not extract route hint for packets whose destination is part of a multipath group. A new SKB flag IP6SKB_MULTIPATH is introduced for this purpose, set the flag when route is looked up in fib6_select_path() and use it in ip6_can_use_hint() to check for the existence of the flag. Fixes: 197dbf24e360 ("ipv6: introduce and uses route look hints for list input.") Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech> --- include/linux/ipv6.h | 1 + net/ipv6/ip6_input.c | 3 ++- net/ipv6/route.c | 2 ++ 3 files changed, 5 insertions(+), 1 deletion(-)