From 93775590b1ee98bf2976b1f4a1ed24e9ff76170f Mon Sep 17 00:00:00 2001 From: Pedro Tammela Date: Fri, 8 Dec 2023 16:28:47 -0300 Subject: [PATCH] net/sched: cls_api: conditional notification of events As of today tc-filter/chain events are unconditionally built and sent to RTNLGRP_TC. As with the introduction of rtnl_notify_needed we can check before-hand if they are really needed. This will help to alleviate system pressure when filters are concurrently added without the rtnl lock as in tc-flower. Reviewed-by: Jiri Pirko Reviewed-by: Simon Horman Signed-off-by: Pedro Tammela Link: https://lore.kernel.org/r/20231208192847.714940-8-pctammela@mojatatu.com Signed-off-by: Jakub Kicinski --- net/sched/cls_api.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c index 4050215a532d..437daebc1fc4 100644 --- a/net/sched/cls_api.c +++ b/net/sched/cls_api.c @@ -2052,6 +2052,9 @@ static int tfilter_notify(struct net *net, struct sk_buff *oskb, u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; int err = 0; + if (!unicast && !rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) + return 0; + skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); if (!skb) return -ENOBUFS; @@ -2081,6 +2084,9 @@ static int tfilter_del_notify(struct net *net, struct sk_buff *oskb, u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; int err; + if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) + return tp->ops->delete(tp, fh, last, rtnl_held, extack); + skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); if (!skb) return -ENOBUFS; @@ -2901,6 +2907,9 @@ static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb, struct sk_buff *skb; int err = 0; + if (!unicast && !rtnl_notify_needed(net, flags, RTNLGRP_TC)) + return 0; + skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); if (!skb) return -ENOBUFS; @@ -2930,6 +2939,9 @@ static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops, struct net *net = block->net; struct sk_buff *skb; + if (!rtnl_notify_needed(net, flags, RTNLGRP_TC)) + return 0; + skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); if (!skb) return -ENOBUFS;