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 <jhs@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This commit is contained in:
Pedro Tammela 2023-02-14 18:15:31 -03:00 committed by Paolo Abeni
parent 10d13421a6
commit 7d12057b45
2 changed files with 56 additions and 26 deletions

View File

@ -5,13 +5,17 @@
#include <linux/types.h>
#include <net/act_api.h>
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)

View File

@ -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),
};