| Message ID | 20211029032604.5432-1-xingwu.yang@gmail.com |
|---|---|
| State | Changes Requested |
| Delegated to: | Pablo Neira |
| Headers | show |
| Series | [v2] ipvs: Fix reuse connection if RS weight is 0 | expand |
Hello, On Fri, 29 Oct 2021, yangxingwu wrote: > Since commit dc7b3eb900aa ("ipvs: Fix reuse connection if real server is > dead"), new connections to dead servers are redistributed immediately to > new servers. > > Then commit d752c3645717 ("ipvs: allow rescheduling of new connections when > port reuse is detected") disable expire_nodest_conn if conn_reuse_mode is > 0. And new connection may be distributed to a real server with weight 0. Can you better explain in commit message that we are changing expire_nodest_conn to work even for reused connections when conn_reuse_mode=0 but without affecting the controlled/persistent connections during the grace period while server is with weight=0. Even if you target -next trees adding commit d752c3645717 as Fixes line would be a good idea. Make sure the tree is specified after the v3 tag. > Co-developed-by: Chuanqi Liu <legend050709@qq.com> > Signed-off-by: Chuanqi Liu <legend050709@qq.com> > Signed-off-by: yangxingwu <xingwu.yang@gmail.com> > --- > Documentation/networking/ipvs-sysctl.rst | 3 +-- > net/netfilter/ipvs/ip_vs_core.c | 7 ++++--- > 2 files changed, 5 insertions(+), 5 deletions(-) > > diff --git a/Documentation/networking/ipvs-sysctl.rst b/Documentation/networking/ipvs-sysctl.rst > index 2afccc63856e..1cfbf1add2fc 100644 > --- a/Documentation/networking/ipvs-sysctl.rst > +++ b/Documentation/networking/ipvs-sysctl.rst > @@ -37,8 +37,7 @@ conn_reuse_mode - INTEGER > > 0: disable any special handling on port reuse. The new > connection will be delivered to the same real server that was > - servicing the previous connection. This will effectively > - disable expire_nodest_conn. > + servicing the previous connection. > > bit 1: enable rescheduling of new connections when it is safe. > That is, whenever expire_nodest_conn and for TCP sockets, when > diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c > index 128690c512df..374f4b0b7080 100644 > --- a/net/netfilter/ipvs/ip_vs_core.c > +++ b/net/netfilter/ipvs/ip_vs_core.c > @@ -2042,14 +2042,15 @@ ip_vs_in(struct netns_ipvs *ipvs, unsigned int hooknum, struct sk_buff *skb, int > ipvs, af, skb, &iph); > > conn_reuse_mode = sysctl_conn_reuse_mode(ipvs); > - if (conn_reuse_mode && !iph.fragoffs && is_new_conn(skb, &iph) && cp) { > + if (!iph.fragoffs && is_new_conn(skb, &iph) && cp) { It is even better to move the !cp->control check above: if (!iph.fragoffs && is_new_conn(skb, &iph) && cp && !cp->control) { Then is not needed in is_new_conn_expected() anymore. > bool old_ct = false, resched = false; And now you can move conn_reuse_mode here: int conn_reuse_mode = sysctl_conn_reuse_mode(ipvs); > if (unlikely(sysctl_expire_nodest_conn(ipvs)) && cp->dest && > - unlikely(!atomic_read(&cp->dest->weight))) { > + unlikely(!atomic_read(&cp->dest->weight)) && !cp->control) { > resched = true; > old_ct = ip_vs_conn_uses_old_conntrack(cp, skb); > - } else if (is_new_conn_expected(cp, conn_reuse_mode)) { > + } else if (conn_reuse_mode && > + is_new_conn_expected(cp, conn_reuse_mode)) { > old_ct = ip_vs_conn_uses_old_conntrack(cp, skb); > if (!atomic_read(&cp->n_control)) { > resched = true; > -- > 2.30.2 Regards -- Julian Anastasov <ja@ssi.bg>
thanks Julian I will do that On Sat, Oct 30, 2021 at 3:25 AM Julian Anastasov <ja@ssi.bg> wrote: > > > Hello, > > On Fri, 29 Oct 2021, yangxingwu wrote: > > > Since commit dc7b3eb900aa ("ipvs: Fix reuse connection if real server is > > dead"), new connections to dead servers are redistributed immediately to > > new servers. > > > > Then commit d752c3645717 ("ipvs: allow rescheduling of new connections when > > port reuse is detected") disable expire_nodest_conn if conn_reuse_mode is > > 0. And new connection may be distributed to a real server with weight 0. > > Can you better explain in commit message that we are changing > expire_nodest_conn to work even for reused connections when > conn_reuse_mode=0 but without affecting the controlled/persistent > connections during the grace period while server is with weight=0. > > Even if you target -next trees adding commit d752c3645717 > as Fixes line would be a good idea. Make sure the tree is specified > after the v3 tag. > > > Co-developed-by: Chuanqi Liu <legend050709@qq.com> > > Signed-off-by: Chuanqi Liu <legend050709@qq.com> > > Signed-off-by: yangxingwu <xingwu.yang@gmail.com> > > --- > > Documentation/networking/ipvs-sysctl.rst | 3 +-- > > net/netfilter/ipvs/ip_vs_core.c | 7 ++++--- > > 2 files changed, 5 insertions(+), 5 deletions(-) > > > > diff --git a/Documentation/networking/ipvs-sysctl.rst b/Documentation/networking/ipvs-sysctl.rst > > index 2afccc63856e..1cfbf1add2fc 100644 > > --- a/Documentation/networking/ipvs-sysctl.rst > > +++ b/Documentation/networking/ipvs-sysctl.rst > > @@ -37,8 +37,7 @@ conn_reuse_mode - INTEGER > > > > 0: disable any special handling on port reuse. The new > > connection will be delivered to the same real server that was > > - servicing the previous connection. This will effectively > > - disable expire_nodest_conn. > > + servicing the previous connection. > > > > bit 1: enable rescheduling of new connections when it is safe. > > That is, whenever expire_nodest_conn and for TCP sockets, when > > diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c > > index 128690c512df..374f4b0b7080 100644 > > --- a/net/netfilter/ipvs/ip_vs_core.c > > +++ b/net/netfilter/ipvs/ip_vs_core.c > > @@ -2042,14 +2042,15 @@ ip_vs_in(struct netns_ipvs *ipvs, unsigned int hooknum, struct sk_buff *skb, int > > ipvs, af, skb, &iph); > > > > conn_reuse_mode = sysctl_conn_reuse_mode(ipvs); > > - if (conn_reuse_mode && !iph.fragoffs && is_new_conn(skb, &iph) && cp) { > > + if (!iph.fragoffs && is_new_conn(skb, &iph) && cp) { > > It is even better to move the !cp->control check above: > > if (!iph.fragoffs && is_new_conn(skb, &iph) && cp && !cp->control) { > > Then is not needed in is_new_conn_expected() anymore. > > > bool old_ct = false, resched = false; > > And now you can move conn_reuse_mode here: > > int conn_reuse_mode = sysctl_conn_reuse_mode(ipvs); > > > if (unlikely(sysctl_expire_nodest_conn(ipvs)) && cp->dest && > > - unlikely(!atomic_read(&cp->dest->weight))) { > > + unlikely(!atomic_read(&cp->dest->weight)) && !cp->control) { > > resched = true; > > old_ct = ip_vs_conn_uses_old_conntrack(cp, skb); > > - } else if (is_new_conn_expected(cp, conn_reuse_mode)) { > > + } else if (conn_reuse_mode && > > + is_new_conn_expected(cp, conn_reuse_mode)) { > > old_ct = ip_vs_conn_uses_old_conntrack(cp, skb); > > if (!atomic_read(&cp->n_control)) { > > resched = true; > > -- > > 2.30.2 > > Regards > > -- > Julian Anastasov <ja@ssi.bg>
diff --git a/Documentation/networking/ipvs-sysctl.rst b/Documentation/networking/ipvs-sysctl.rst index 2afccc63856e..1cfbf1add2fc 100644 --- a/Documentation/networking/ipvs-sysctl.rst +++ b/Documentation/networking/ipvs-sysctl.rst @@ -37,8 +37,7 @@ conn_reuse_mode - INTEGER 0: disable any special handling on port reuse. The new connection will be delivered to the same real server that was - servicing the previous connection. This will effectively - disable expire_nodest_conn. + servicing the previous connection. bit 1: enable rescheduling of new connections when it is safe. That is, whenever expire_nodest_conn and for TCP sockets, when diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c index 128690c512df..374f4b0b7080 100644 --- a/net/netfilter/ipvs/ip_vs_core.c +++ b/net/netfilter/ipvs/ip_vs_core.c @@ -2042,14 +2042,15 @@ ip_vs_in(struct netns_ipvs *ipvs, unsigned int hooknum, struct sk_buff *skb, int ipvs, af, skb, &iph); conn_reuse_mode = sysctl_conn_reuse_mode(ipvs); - if (conn_reuse_mode && !iph.fragoffs && is_new_conn(skb, &iph) && cp) { + if (!iph.fragoffs && is_new_conn(skb, &iph) && cp) { bool old_ct = false, resched = false; if (unlikely(sysctl_expire_nodest_conn(ipvs)) && cp->dest && - unlikely(!atomic_read(&cp->dest->weight))) { + unlikely(!atomic_read(&cp->dest->weight)) && !cp->control) { resched = true; old_ct = ip_vs_conn_uses_old_conntrack(cp, skb); - } else if (is_new_conn_expected(cp, conn_reuse_mode)) { + } else if (conn_reuse_mode && + is_new_conn_expected(cp, conn_reuse_mode)) { old_ct = ip_vs_conn_uses_old_conntrack(cp, skb); if (!atomic_read(&cp->n_control)) { resched = true;
Since commit dc7b3eb900aa ("ipvs: Fix reuse connection if real server is dead"), new connections to dead servers are redistributed immediately to new servers. Then commit d752c3645717 ("ipvs: allow rescheduling of new connections when port reuse is detected") disable expire_nodest_conn if conn_reuse_mode is 0. And new connection may be distributed to a real server with weight 0. Co-developed-by: Chuanqi Liu <legend050709@qq.com> Signed-off-by: Chuanqi Liu <legend050709@qq.com> Signed-off-by: yangxingwu <xingwu.yang@gmail.com> --- Documentation/networking/ipvs-sysctl.rst | 3 +-- net/netfilter/ipvs/ip_vs_core.c | 7 ++++--- 2 files changed, 5 insertions(+), 5 deletions(-)