diff mbox series

[net-next,2/3] net/sched: act_connmark: transition to percpu stats and rcu

Message ID 20230210202725.446422-3-pctammela@mojatatu.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series net/sched: transition actions to pcpu stats and rcu | expand

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Commit Message

Pedro Tammela Feb. 10, 2023, 8:27 p.m. UTC
The tc action act_connmark was using shared stats and taking the per
action lock in the datapath. Improve it by using percpu stats and rcu.

perf before:
- 13.55% tcf_connmark_act
   - 81.18% _raw_spin_lock
       80.46% native_queued_spin_lock_slowpath

perf after:
- 3.12% tcf_connmark_act

tdc results:
1..15
ok 1 2002 - Add valid connmark action with defaults
ok 2 56a5 - Add valid connmark action with control pass
ok 3 7c66 - Add valid connmark action with control drop
ok 4 a913 - Add valid connmark action with control pipe
ok 5 bdd8 - Add valid connmark action with control reclassify
ok 6 b8be - Add valid connmark action with control continue
ok 7 d8a6 - Add valid connmark action with control jump
ok 8 aae8 - Add valid connmark action with zone argument
ok 9 2f0b - Add valid connmark action with invalid zone argument
ok 10 9305 - Add connmark action with unsupported argument
ok 11 71ca - Add valid connmark action and replace it
ok 12 5f8f - Add valid connmark action with cookie
ok 13 c506 - Replace connmark with invalid goto chain control
ok 14 6571 - Delete connmark action with valid index
ok 15 3426 - Delete connmark action with invalid index

Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
---
 include/net/tc_act/tc_connmark.h |   9 ++-
 net/sched/act_connmark.c         | 109 ++++++++++++++++++++-----------
 2 files changed, 77 insertions(+), 41 deletions(-)

Comments

Paolo Abeni Feb. 14, 2023, 9:03 a.m. UTC | #1
On Fri, 2023-02-10 at 17:27 -0300, Pedro Tammela wrote:
> The tc action act_connmark was using shared stats and taking the per
> action lock in the datapath. Improve it by using percpu stats and rcu.
> 
> perf before:
> - 13.55% tcf_connmark_act
>    - 81.18% _raw_spin_lock
>        80.46% native_queued_spin_lock_slowpath
> 
> perf after:
> - 3.12% tcf_connmark_act
> 
> tdc results:
> 1..15
> ok 1 2002 - Add valid connmark action with defaults
> ok 2 56a5 - Add valid connmark action with control pass
> ok 3 7c66 - Add valid connmark action with control drop
> ok 4 a913 - Add valid connmark action with control pipe
> ok 5 bdd8 - Add valid connmark action with control reclassify
> ok 6 b8be - Add valid connmark action with control continue
> ok 7 d8a6 - Add valid connmark action with control jump
> ok 8 aae8 - Add valid connmark action with zone argument
> ok 9 2f0b - Add valid connmark action with invalid zone argument
> ok 10 9305 - Add connmark action with unsupported argument
> ok 11 71ca - Add valid connmark action and replace it
> ok 12 5f8f - Add valid connmark action with cookie
> ok 13 c506 - Replace connmark with invalid goto chain control
> ok 14 6571 - Delete connmark action with valid index
> ok 15 3426 - Delete connmark action with invalid index
> 
> Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
> Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
> ---
>  include/net/tc_act/tc_connmark.h |   9 ++-
>  net/sched/act_connmark.c         | 109 ++++++++++++++++++++-----------
>  2 files changed, 77 insertions(+), 41 deletions(-)
> 
> diff --git a/include/net/tc_act/tc_connmark.h b/include/net/tc_act/tc_connmark.h
> index 1f4cb477b..e8dd77a96 100644
> --- a/include/net/tc_act/tc_connmark.h
> +++ b/include/net/tc_act/tc_connmark.h
> @@ -4,10 +4,15 @@
>  
>  #include <net/act_api.h>
>  
> -struct tcf_connmark_info {
> -	struct tc_action common;
> +struct tcf_connmark_parms {
>  	struct net *net;
>  	u16 zone;
> +	struct rcu_head rcu;
> +};
> +
> +struct tcf_connmark_info {
> +	struct tc_action common;
> +	struct tcf_connmark_parms __rcu *parms;
>  };
>  
>  #define to_connmark(a) ((struct tcf_connmark_info *)a)
> diff --git a/net/sched/act_connmark.c b/net/sched/act_connmark.c
> index 7e63ff7e3..541e1c556 100644
> --- a/net/sched/act_connmark.c
> +++ b/net/sched/act_connmark.c
> @@ -36,13 +36,15 @@ TC_INDIRECT_SCOPE int tcf_connmark_act(struct sk_buff *skb,
>  	struct nf_conntrack_tuple tuple;
>  	enum ip_conntrack_info ctinfo;
>  	struct tcf_connmark_info *ca = to_connmark(a);
> +	struct tcf_connmark_parms *parms;
>  	struct nf_conntrack_zone zone;
>  	struct nf_conn *c;
>  	int proto;
>  
> -	spin_lock(&ca->tcf_lock);
>  	tcf_lastuse_update(&ca->tcf_tm);
> -	bstats_update(&ca->tcf_bstats, skb);
> +	tcf_action_update_bstats(&ca->common, skb);
> +
> +	parms = rcu_dereference_bh(ca->parms);
>  
>  	switch (skb_protocol(skb, true)) {
>  	case htons(ETH_P_IP):
> @@ -64,31 +66,31 @@ TC_INDIRECT_SCOPE int tcf_connmark_act(struct sk_buff *skb,
>  	c = nf_ct_get(skb, &ctinfo);
>  	if (c) {
>  		skb->mark = READ_ONCE(c->mark);
> -		/* using overlimits stats to count how many packets marked */
> -		ca->tcf_qstats.overlimits++;
> -		goto out;
> +		goto count;
>  	}
>  
> -	if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb),
> -			       proto, ca->net, &tuple))
> +	if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), proto, parms->net,
> +			       &tuple))
>  		goto out;
>  
> -	zone.id = ca->zone;
> +	zone.id = parms->zone;
>  	zone.dir = NF_CT_DEFAULT_ZONE_DIR;
>  
> -	thash = nf_conntrack_find_get(ca->net, &zone, &tuple);
> +	thash = nf_conntrack_find_get(parms->net, &zone, &tuple);
>  	if (!thash)
>  		goto out;
>  
>  	c = nf_ct_tuplehash_to_ctrack(thash);
> -	/* using overlimits stats to count how many packets marked */
> -	ca->tcf_qstats.overlimits++;
>  	skb->mark = READ_ONCE(c->mark);
>  	nf_ct_put(c);
>  
> -out:
> +count:
> +	/* using overlimits stats to count how many packets marked */
> +	spin_lock(&ca->tcf_lock);
> +	ca->tcf_qstats.overlimits++;
>  	spin_unlock(&ca->tcf_lock);

I think above you could use tcf_action_inc_overlimit_qstats() and avoid
acquiring the spin lock in most cases.

Side note: it looks like pedit could use a similar change, too - sorry
for missing that point before.

> -	return ca->tcf_action;
> +out:
> +	return READ_ONCE(ca->tcf_action);
>  }
>  
>  static const struct nla_policy connmark_policy[TCA_CONNMARK_MAX + 1] = {
> @@ -104,6 +106,7 @@ static int tcf_connmark_init(struct net *net, struct nlattr *nla,
>  	struct nlattr *tb[TCA_CONNMARK_MAX + 1];
>  	bool bind = flags & TCA_ACT_FLAGS_BIND;
>  	struct tcf_chain *goto_ch = NULL;
> +	struct tcf_connmark_parms *nparms, *oparms;
>  	struct tcf_connmark_info *ci;
>  	struct tc_connmark *parm;
>  	int ret = 0, err;

Please respect the reverse x-mas tree above.


Thanks,

Paolo
Pedro Tammela Feb. 14, 2023, 2:31 p.m. UTC | #2
On 14/02/2023 06:03, Paolo Abeni wrote:
> On Fri, 2023-02-10 at 17:27 -0300, Pedro Tammela wrote:
>> The tc action act_connmark was using shared stats and taking the per
>> action lock in the datapath. Improve it by using percpu stats and rcu.
>>
>> perf before:
>> - 13.55% tcf_connmark_act
>>     - 81.18% _raw_spin_lock
>>         80.46% native_queued_spin_lock_slowpath
>>
>> perf after:
>> - 3.12% tcf_connmark_act
>>
>> tdc results:
>> 1..15
>> ok 1 2002 - Add valid connmark action with defaults
>> ok 2 56a5 - Add valid connmark action with control pass
>> ok 3 7c66 - Add valid connmark action with control drop
>> ok 4 a913 - Add valid connmark action with control pipe
>> ok 5 bdd8 - Add valid connmark action with control reclassify
>> ok 6 b8be - Add valid connmark action with control continue
>> ok 7 d8a6 - Add valid connmark action with control jump
>> ok 8 aae8 - Add valid connmark action with zone argument
>> ok 9 2f0b - Add valid connmark action with invalid zone argument
>> ok 10 9305 - Add connmark action with unsupported argument
>> ok 11 71ca - Add valid connmark action and replace it
>> ok 12 5f8f - Add valid connmark action with cookie
>> ok 13 c506 - Replace connmark with invalid goto chain control
>> ok 14 6571 - Delete connmark action with valid index
>> ok 15 3426 - Delete connmark action with invalid index
>>
>> Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
>> Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
>> ---
>>   include/net/tc_act/tc_connmark.h |   9 ++-
>>   net/sched/act_connmark.c         | 109 ++++++++++++++++++++-----------
>>   2 files changed, 77 insertions(+), 41 deletions(-)
>>
>> diff --git a/include/net/tc_act/tc_connmark.h b/include/net/tc_act/tc_connmark.h
>> index 1f4cb477b..e8dd77a96 100644
>> --- a/include/net/tc_act/tc_connmark.h
>> +++ b/include/net/tc_act/tc_connmark.h
>> @@ -4,10 +4,15 @@
>>   
>>   #include <net/act_api.h>
>>   
>> -struct tcf_connmark_info {
>> -	struct tc_action common;
>> +struct tcf_connmark_parms {
>>   	struct net *net;
>>   	u16 zone;
>> +	struct rcu_head rcu;
>> +};
>> +
>> +struct tcf_connmark_info {
>> +	struct tc_action common;
>> +	struct tcf_connmark_parms __rcu *parms;
>>   };
>>   
>>   #define to_connmark(a) ((struct tcf_connmark_info *)a)
>> diff --git a/net/sched/act_connmark.c b/net/sched/act_connmark.c
>> index 7e63ff7e3..541e1c556 100644
>> --- a/net/sched/act_connmark.c
>> +++ b/net/sched/act_connmark.c
>> @@ -36,13 +36,15 @@ TC_INDIRECT_SCOPE int tcf_connmark_act(struct sk_buff *skb,
>>   	struct nf_conntrack_tuple tuple;
>>   	enum ip_conntrack_info ctinfo;
>>   	struct tcf_connmark_info *ca = to_connmark(a);
>> +	struct tcf_connmark_parms *parms;
>>   	struct nf_conntrack_zone zone;
>>   	struct nf_conn *c;
>>   	int proto;
>>   
>> -	spin_lock(&ca->tcf_lock);
>>   	tcf_lastuse_update(&ca->tcf_tm);
>> -	bstats_update(&ca->tcf_bstats, skb);
>> +	tcf_action_update_bstats(&ca->common, skb);
>> +
>> +	parms = rcu_dereference_bh(ca->parms);
>>   
>>   	switch (skb_protocol(skb, true)) {
>>   	case htons(ETH_P_IP):
>> @@ -64,31 +66,31 @@ TC_INDIRECT_SCOPE int tcf_connmark_act(struct sk_buff *skb,
>>   	c = nf_ct_get(skb, &ctinfo);
>>   	if (c) {
>>   		skb->mark = READ_ONCE(c->mark);
>> -		/* using overlimits stats to count how many packets marked */
>> -		ca->tcf_qstats.overlimits++;
>> -		goto out;
>> +		goto count;
>>   	}
>>   
>> -	if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb),
>> -			       proto, ca->net, &tuple))
>> +	if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), proto, parms->net,
>> +			       &tuple))
>>   		goto out;
>>   
>> -	zone.id = ca->zone;
>> +	zone.id = parms->zone;
>>   	zone.dir = NF_CT_DEFAULT_ZONE_DIR;
>>   
>> -	thash = nf_conntrack_find_get(ca->net, &zone, &tuple);
>> +	thash = nf_conntrack_find_get(parms->net, &zone, &tuple);
>>   	if (!thash)
>>   		goto out;
>>   
>>   	c = nf_ct_tuplehash_to_ctrack(thash);
>> -	/* using overlimits stats to count how many packets marked */
>> -	ca->tcf_qstats.overlimits++;
>>   	skb->mark = READ_ONCE(c->mark);
>>   	nf_ct_put(c);
>>   
>> -out:
>> +count:
>> +	/* using overlimits stats to count how many packets marked */
>> +	spin_lock(&ca->tcf_lock);
>> +	ca->tcf_qstats.overlimits++;
>>   	spin_unlock(&ca->tcf_lock);
> 
> I think above you could use tcf_action_inc_overlimit_qstats() and avoid
> acquiring the spin lock in most cases.
> 
> Side note: it looks like pedit could use a similar change, too - sorry
> for missing that point before.
> 

Oh, indeed! I will respin and add the pedit change in this series as well.
Many thanks.
diff mbox series

Patch

diff --git a/include/net/tc_act/tc_connmark.h b/include/net/tc_act/tc_connmark.h
index 1f4cb477b..e8dd77a96 100644
--- a/include/net/tc_act/tc_connmark.h
+++ b/include/net/tc_act/tc_connmark.h
@@ -4,10 +4,15 @@ 
 
 #include <net/act_api.h>
 
-struct tcf_connmark_info {
-	struct tc_action common;
+struct tcf_connmark_parms {
 	struct net *net;
 	u16 zone;
+	struct rcu_head rcu;
+};
+
+struct tcf_connmark_info {
+	struct tc_action common;
+	struct tcf_connmark_parms __rcu *parms;
 };
 
 #define to_connmark(a) ((struct tcf_connmark_info *)a)
diff --git a/net/sched/act_connmark.c b/net/sched/act_connmark.c
index 7e63ff7e3..541e1c556 100644
--- a/net/sched/act_connmark.c
+++ b/net/sched/act_connmark.c
@@ -36,13 +36,15 @@  TC_INDIRECT_SCOPE int tcf_connmark_act(struct sk_buff *skb,
 	struct nf_conntrack_tuple tuple;
 	enum ip_conntrack_info ctinfo;
 	struct tcf_connmark_info *ca = to_connmark(a);
+	struct tcf_connmark_parms *parms;
 	struct nf_conntrack_zone zone;
 	struct nf_conn *c;
 	int proto;
 
-	spin_lock(&ca->tcf_lock);
 	tcf_lastuse_update(&ca->tcf_tm);
-	bstats_update(&ca->tcf_bstats, skb);
+	tcf_action_update_bstats(&ca->common, skb);
+
+	parms = rcu_dereference_bh(ca->parms);
 
 	switch (skb_protocol(skb, true)) {
 	case htons(ETH_P_IP):
@@ -64,31 +66,31 @@  TC_INDIRECT_SCOPE int tcf_connmark_act(struct sk_buff *skb,
 	c = nf_ct_get(skb, &ctinfo);
 	if (c) {
 		skb->mark = READ_ONCE(c->mark);
-		/* using overlimits stats to count how many packets marked */
-		ca->tcf_qstats.overlimits++;
-		goto out;
+		goto count;
 	}
 
-	if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb),
-			       proto, ca->net, &tuple))
+	if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), proto, parms->net,
+			       &tuple))
 		goto out;
 
-	zone.id = ca->zone;
+	zone.id = parms->zone;
 	zone.dir = NF_CT_DEFAULT_ZONE_DIR;
 
-	thash = nf_conntrack_find_get(ca->net, &zone, &tuple);
+	thash = nf_conntrack_find_get(parms->net, &zone, &tuple);
 	if (!thash)
 		goto out;
 
 	c = nf_ct_tuplehash_to_ctrack(thash);
-	/* using overlimits stats to count how many packets marked */
-	ca->tcf_qstats.overlimits++;
 	skb->mark = READ_ONCE(c->mark);
 	nf_ct_put(c);
 
-out:
+count:
+	/* using overlimits stats to count how many packets marked */
+	spin_lock(&ca->tcf_lock);
+	ca->tcf_qstats.overlimits++;
 	spin_unlock(&ca->tcf_lock);
-	return ca->tcf_action;
+out:
+	return READ_ONCE(ca->tcf_action);
 }
 
 static const struct nla_policy connmark_policy[TCA_CONNMARK_MAX + 1] = {
@@ -104,6 +106,7 @@  static int tcf_connmark_init(struct net *net, struct nlattr *nla,
 	struct nlattr *tb[TCA_CONNMARK_MAX + 1];
 	bool bind = flags & TCA_ACT_FLAGS_BIND;
 	struct tcf_chain *goto_ch = NULL;
+	struct tcf_connmark_parms *nparms, *oparms;
 	struct tcf_connmark_info *ci;
 	struct tc_connmark *parm;
 	int ret = 0, err;
@@ -120,52 +123,66 @@  static int tcf_connmark_init(struct net *net, struct nlattr *nla,
 	if (!tb[TCA_CONNMARK_PARMS])
 		return -EINVAL;
 
+	nparms = kzalloc(sizeof(*nparms), GFP_KERNEL);
+	if (!nparms)
+		return -ENOMEM;
+
 	parm = nla_data(tb[TCA_CONNMARK_PARMS]);
 	index = parm->index;
 	ret = tcf_idr_check_alloc(tn, &index, a, bind);
 	if (!ret) {
-		ret = tcf_idr_create(tn, index, est, a,
-				     &act_connmark_ops, bind, false, flags);
+		ret = tcf_idr_create_from_flags(tn, index, est, a,
+						&act_connmark_ops, bind, flags);
 		if (ret) {
 			tcf_idr_cleanup(tn, index);
-			return ret;
+			err = ret;
+			goto out_free;
 		}
 
 		ci = to_connmark(*a);
-		err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch,
-					       extack);
-		if (err < 0)
-			goto release_idr;
-		tcf_action_set_ctrlact(*a, parm->action, goto_ch);
-		ci->net = net;
-		ci->zone = parm->zone;
+
+		nparms->net = net;
+		nparms->zone = parm->zone;
 
 		ret = ACT_P_CREATED;
 	} else if (ret > 0) {
 		ci = to_connmark(*a);
-		if (bind)
-			return 0;
-		if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
-			tcf_idr_release(*a, bind);
-			return -EEXIST;
+		if (bind) {
+			err = 0;
+			goto out_free;
 		}
-		err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch,
-					       extack);
-		if (err < 0)
+		if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
+			err = -EEXIST;
 			goto release_idr;
-		/* replacing action and zone */
-		spin_lock_bh(&ci->tcf_lock);
-		goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
-		ci->zone = parm->zone;
-		spin_unlock_bh(&ci->tcf_lock);
-		if (goto_ch)
-			tcf_chain_put_by_act(goto_ch);
+		}
+
+		nparms->net = rtnl_dereference(ci->parms)->net;
+		nparms->zone = parm->zone;
+
 		ret = 0;
 	}
 
+	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
+	if (err < 0)
+		goto release_idr;
+
+	spin_lock_bh(&ci->tcf_lock);
+	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
+	oparms = rcu_replace_pointer(ci->parms, nparms, lockdep_is_held(&ci->tcf_lock));
+	spin_unlock_bh(&ci->tcf_lock);
+
+	if (goto_ch)
+		tcf_chain_put_by_act(goto_ch);
+
+	if (oparms)
+		kfree_rcu(oparms, rcu);
+
 	return ret;
+
 release_idr:
 	tcf_idr_release(*a, bind);
+out_free:
+	kfree(nparms);
 	return err;
 }
 
@@ -179,11 +196,14 @@  static inline int tcf_connmark_dump(struct sk_buff *skb, struct tc_action *a,
 		.refcnt  = refcount_read(&ci->tcf_refcnt) - ref,
 		.bindcnt = atomic_read(&ci->tcf_bindcnt) - bind,
 	};
+	struct tcf_connmark_parms *parms;
 	struct tcf_t t;
 
 	spin_lock_bh(&ci->tcf_lock);
+	parms = rcu_dereference_protected(ci->parms, lockdep_is_held(&ci->tcf_lock));
+
 	opt.action = ci->tcf_action;
-	opt.zone = ci->zone;
+	opt.zone = parms->zone;
 	if (nla_put(skb, TCA_CONNMARK_PARMS, sizeof(opt), &opt))
 		goto nla_put_failure;
 
@@ -201,6 +221,16 @@  static inline int tcf_connmark_dump(struct sk_buff *skb, struct tc_action *a,
 	return -1;
 }
 
+static void tcf_connmark_cleanup(struct tc_action *a)
+{
+	struct tcf_connmark_parms *parms;
+	struct tcf_connmark_info *ci = to_connmark(a);
+
+	parms = rcu_dereference_protected(ci->parms, 1);
+	if (parms)
+		kfree_rcu(parms, rcu);
+}
+
 static struct tc_action_ops act_connmark_ops = {
 	.kind		=	"connmark",
 	.id		=	TCA_ID_CONNMARK,
@@ -208,6 +238,7 @@  static struct tc_action_ops act_connmark_ops = {
 	.act		=	tcf_connmark_act,
 	.dump		=	tcf_connmark_dump,
 	.init		=	tcf_connmark_init,
+	.cleanup	=	tcf_connmark_cleanup,
 	.size		=	sizeof(struct tcf_connmark_info),
 };