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 <jiri@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Link: https://lore.kernel.org/r/20231208192847.714940-8-pctammela@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Pedro Tammela 2023-12-08 16:28:47 -03:00 committed by Jakub Kicinski
parent e522755520
commit 93775590b1

View File

@ -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;