net: sched: add percpu stats to actions

Reuse existing percpu infrastructure John Fastabend added for qdisc.

This patch adds a new cpustats parameter to tcf_hash_create() and all
actions pass false, meaning this patch should have no effect yet.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 34 insertions, 10 deletions

diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index af427a3dbcba..074a32f466f8 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -27,6 +27,15 @@
 #include <net/act_api.h>
 #include <net/netlink.h>
 
+static void free_tcf(struct rcu_head *head)
+{
+	struct tcf_common *p = container_of(head, struct tcf_common, tcfc_rcu);
+
+	free_percpu(p->cpu_bstats);
+	free_percpu(p->cpu_qstats);
+	kfree(p);
+}
+
 void tcf_hash_destroy(struct tc_action *a)
 {
 	struct tcf_common *p = a->priv;
@@ -41,7 +50,7 @@ void tcf_hash_destroy(struct tc_action *a)
 	 * gen_estimator est_timer() might access p->tcfc_lock
 	 * or bstats, wait a RCU grace period before freeing p
 	 */
-	kfree_rcu(p, tcfc_rcu);
+	call_rcu(&p->tcfc_rcu, free_tcf);
 }
 EXPORT_SYMBOL(tcf_hash_destroy);
 
@@ -230,15 +239,16 @@ void tcf_hash_cleanup(struct tc_action *a, struct nlattr *est)
 	if (est)
 		gen_kill_estimator(&pc->tcfc_bstats,
 				   &pc->tcfc_rate_est);
-	kfree_rcu(pc, tcfc_rcu);
+	call_rcu(&pc->tcfc_rcu, free_tcf);
 }
 EXPORT_SYMBOL(tcf_hash_cleanup);
 
 int tcf_hash_create(u32 index, struct nlattr *est, struct tc_action *a,
-		    int size, int bind)
+		    int size, int bind, bool cpustats)
 {
 	struct tcf_hashinfo *hinfo = a->ops->hinfo;
 	struct tcf_common *p = kzalloc(size, GFP_KERNEL);
+	int err = -ENOMEM;
 
 	if (unlikely(!p))
 		return -ENOMEM;
@@ -246,18 +256,32 @@ int tcf_hash_create(u32 index, struct nlattr *est, struct tc_action *a,
 	if (bind)
 		p->tcfc_bindcnt = 1;
 
+	if (cpustats) {
+		p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
+		if (!p->cpu_bstats) {
+err1:
+			kfree(p);
+			return err;
+		}
+		p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
+		if (!p->cpu_qstats) {
+err2:
+			free_percpu(p->cpu_bstats);
+			goto err1;
+		}
+	}
 	spin_lock_init(&p->tcfc_lock);
 	INIT_HLIST_NODE(&p->tcfc_head);
 	p->tcfc_index = index ? index : tcf_hash_new_index(hinfo);
 	p->tcfc_tm.install = jiffies;
 	p->tcfc_tm.lastuse = jiffies;
 	if (est) {
-		int err = gen_new_estimator(&p->tcfc_bstats, NULL,
-					    &p->tcfc_rate_est,
-					    &p->tcfc_lock, est);
+		err = gen_new_estimator(&p->tcfc_bstats, p->cpu_bstats,
+					&p->tcfc_rate_est,
+					&p->tcfc_lock, est);
 		if (err) {
-			kfree(p);
-			return err;
+			free_percpu(p->cpu_qstats);
+			goto err2;
 		}
 	}
 
@@ -615,10 +639,10 @@ int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *a,
 	if (err < 0)
 		goto errout;
 
-	if (gnet_stats_copy_basic(&d, NULL, &p->tcfc_bstats) < 0 ||
+	if (gnet_stats_copy_basic(&d, p->cpu_bstats, &p->tcfc_bstats) < 0 ||
 	    gnet_stats_copy_rate_est(&d, &p->tcfc_bstats,
 				     &p->tcfc_rate_est) < 0 ||
-	    gnet_stats_copy_queue(&d, NULL,
+	    gnet_stats_copy_queue(&d, p->cpu_qstats,
 				  &p->tcfc_qstats,
 				  p->tcfc_qstats.qlen) < 0)
 		goto errout;