From 7d12057b45fbc1e1315d327dca13e8d6b5019113 Mon Sep 17 00:00:00 2001 From: Pedro Tammela Date: Tue, 14 Feb 2023 18:15:31 -0300 Subject: [PATCH] net/sched: act_nat: transition to percpu stats and rcu The tc action act_nat was using shared stats and taking the per action lock in the datapath. Improve it by using percpu stats and rcu. perf before: - 10.48% tcf_nat_act - 81.83% _raw_spin_lock 81.08% native_queued_spin_lock_slowpath perf after: - 0.48% tcf_nat_act tdc results: 1..27 ok 1 7565 - Add nat action on ingress with default control action ok 2 fd79 - Add nat action on ingress with pipe control action ok 3 eab9 - Add nat action on ingress with continue control action ok 4 c53a - Add nat action on ingress with reclassify control action ok 5 76c9 - Add nat action on ingress with jump control action ok 6 24c6 - Add nat action on ingress with drop control action ok 7 2120 - Add nat action on ingress with maximum index value ok 8 3e9d - Add nat action on ingress with invalid index value ok 9 f6c9 - Add nat action on ingress with invalid IP address ok 10 be25 - Add nat action on ingress with invalid argument ok 11 a7bd - Add nat action on ingress with DEFAULT IP address ok 12 ee1e - Add nat action on ingress with ANY IP address ok 13 1de8 - Add nat action on ingress with ALL IP address ok 14 8dba - Add nat action on egress with default control action ok 15 19a7 - Add nat action on egress with pipe control action ok 16 f1d9 - Add nat action on egress with continue control action ok 17 6d4a - Add nat action on egress with reclassify control action ok 18 b313 - Add nat action on egress with jump control action ok 19 d9fc - Add nat action on egress with drop control action ok 20 a895 - Add nat action on egress with DEFAULT IP address ok 21 2572 - Add nat action on egress with ANY IP address ok 22 37f3 - Add nat action on egress with ALL IP address ok 23 6054 - Add nat action on egress with cookie ok 24 79d6 - Add nat action on ingress with cookie ok 25 4b12 - Replace nat action with invalid goto chain control ok 26 b811 - Delete nat action with valid index ok 27 a521 - Delete nat action with invalid index Reviewed-by: Jamal Hadi Salim Signed-off-by: Pedro Tammela Signed-off-by: Paolo Abeni --- include/net/tc_act/tc_nat.h | 10 +++++-- net/sched/act_nat.c | 72 ++++++++++++++++++++++++++++++--------------- 2 files changed, 56 insertions(+), 26 deletions(-) diff --git a/include/net/tc_act/tc_nat.h b/include/net/tc_act/tc_nat.h index c144071..c869274 100644 --- a/include/net/tc_act/tc_nat.h +++ b/include/net/tc_act/tc_nat.h @@ -5,13 +5,17 @@ #include #include -struct tcf_nat { - struct tc_action common; - +struct tcf_nat_parms { __be32 old_addr; __be32 new_addr; __be32 mask; u32 flags; + struct rcu_head rcu; +}; + +struct tcf_nat { + struct tc_action common; + struct tcf_nat_parms __rcu *parms; }; #define to_tcf_nat(a) ((struct tcf_nat *)a) diff --git a/net/sched/act_nat.c b/net/sched/act_nat.c index 74c74be..4184af5 100644 --- a/net/sched/act_nat.c +++ b/net/sched/act_nat.c @@ -38,6 +38,7 @@ static int tcf_nat_init(struct net *net, struct nlattr *nla, struct nlattr *est, { struct tc_action_net *tn = net_generic(net, act_nat_ops.net_id); bool bind = flags & TCA_ACT_FLAGS_BIND; + struct tcf_nat_parms *nparm, *oparm; struct nlattr *tb[TCA_NAT_MAX + 1]; struct tcf_chain *goto_ch = NULL; struct tc_nat *parm; @@ -59,8 +60,8 @@ static int tcf_nat_init(struct net *net, struct nlattr *nla, struct nlattr *est, index = parm->index; err = tcf_idr_check_alloc(tn, &index, a, bind); if (!err) { - ret = tcf_idr_create(tn, index, est, a, - &act_nat_ops, bind, false, flags); + ret = tcf_idr_create_from_flags(tn, index, est, a, &act_nat_ops, + bind, flags); if (ret) { tcf_idr_cleanup(tn, index); return ret; @@ -79,19 +80,31 @@ static int tcf_nat_init(struct net *net, struct nlattr *nla, struct nlattr *est, err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack); if (err < 0) goto release_idr; + + nparm = kzalloc(sizeof(*nparm), GFP_KERNEL); + if (!nparm) { + err = -ENOMEM; + goto release_idr; + } + + nparm->old_addr = parm->old_addr; + nparm->new_addr = parm->new_addr; + nparm->mask = parm->mask; + nparm->flags = parm->flags; + p = to_tcf_nat(*a); spin_lock_bh(&p->tcf_lock); - p->old_addr = parm->old_addr; - p->new_addr = parm->new_addr; - p->mask = parm->mask; - p->flags = parm->flags; - goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); + oparm = rcu_replace_pointer(p->parms, nparm, lockdep_is_held(&p->tcf_lock)); spin_unlock_bh(&p->tcf_lock); + if (goto_ch) tcf_chain_put_by_act(goto_ch); + if (oparm) + kfree_rcu(oparm, rcu); + return ret; release_idr: tcf_idr_release(*a, bind); @@ -103,6 +116,7 @@ TC_INDIRECT_SCOPE int tcf_nat_act(struct sk_buff *skb, struct tcf_result *res) { struct tcf_nat *p = to_tcf_nat(a); + struct tcf_nat_parms *parms; struct iphdr *iph; __be32 old_addr; __be32 new_addr; @@ -113,18 +127,16 @@ TC_INDIRECT_SCOPE int tcf_nat_act(struct sk_buff *skb, int ihl; int noff; - spin_lock(&p->tcf_lock); - tcf_lastuse_update(&p->tcf_tm); - old_addr = p->old_addr; - new_addr = p->new_addr; - mask = p->mask; - egress = p->flags & TCA_NAT_FLAG_EGRESS; - action = p->tcf_action; + tcf_action_update_bstats(&p->common, skb); - bstats_update(&p->tcf_bstats, skb); + action = READ_ONCE(p->tcf_action); - spin_unlock(&p->tcf_lock); + parms = rcu_dereference_bh(p->parms); + old_addr = parms->old_addr; + new_addr = parms->new_addr; + mask = parms->mask; + egress = parms->flags & TCA_NAT_FLAG_EGRESS; if (unlikely(action == TC_ACT_SHOT)) goto drop; @@ -248,9 +260,7 @@ out: return action; drop: - spin_lock(&p->tcf_lock); - p->tcf_qstats.drops++; - spin_unlock(&p->tcf_lock); + tcf_action_inc_drop_qstats(&p->common); return TC_ACT_SHOT; } @@ -264,15 +274,20 @@ static int tcf_nat_dump(struct sk_buff *skb, struct tc_action *a, .refcnt = refcount_read(&p->tcf_refcnt) - ref, .bindcnt = atomic_read(&p->tcf_bindcnt) - bind, }; + struct tcf_nat_parms *parms; struct tcf_t t; spin_lock_bh(&p->tcf_lock); - opt.old_addr = p->old_addr; - opt.new_addr = p->new_addr; - opt.mask = p->mask; - opt.flags = p->flags; + opt.action = p->tcf_action; + parms = rcu_dereference_protected(p->parms, lockdep_is_held(&p->tcf_lock)); + + opt.old_addr = parms->old_addr; + opt.new_addr = parms->new_addr; + opt.mask = parms->mask; + opt.flags = parms->flags; + if (nla_put(skb, TCA_NAT_PARMS, sizeof(opt), &opt)) goto nla_put_failure; @@ -289,6 +304,16 @@ nla_put_failure: return -1; } +static void tcf_nat_cleanup(struct tc_action *a) +{ + struct tcf_nat *p = to_tcf_nat(a); + struct tcf_nat_parms *parms; + + parms = rcu_dereference_protected(p->parms, 1); + if (parms) + kfree_rcu(parms, rcu); +} + static struct tc_action_ops act_nat_ops = { .kind = "nat", .id = TCA_ID_NAT, @@ -296,6 +321,7 @@ static struct tc_action_ops act_nat_ops = { .act = tcf_nat_act, .dump = tcf_nat_dump, .init = tcf_nat_init, + .cleanup = tcf_nat_cleanup, .size = sizeof(struct tcf_nat), }; -- 2.7.4