[PATCH net-next 05/13] net: sched: modify stats helper functions to support regular stats

[Vlad Buslov]

Modify stats update helper functions introduced in previous patches in this
series to fallback to regular tc_action->tcfa_{b|q}stats if cpu stats are
not allocated for the action argument. If regular non-percpu allocated
counters are in use, then obtain action tcfa_lock while modifying them.

Signed-off-by: Vlad Buslov <vla...@mellanox.com>
Acked-by: Jiri Pirko <j...@mellanox.com>
---
 include/net/act_api.h | 30 +++++++++++++++++++++---------
 net/sched/act_api.c   | 19 ++++++++++++++-----
 2 files changed, 35 insertions(+), 14 deletions(-)

diff --git a/include/net/act_api.h b/include/net/act_api.h
index 8d6861ce205b..a56477051dae 100644
--- a/include/net/act_api.h
+++ b/include/net/act_api.h
@@ -190,23 +190,35 @@ int tcf_action_dump_1(struct sk_buff *skb, struct 
tc_action *a, int, int);
 static inline void tcf_action_update_bstats(struct tc_action *a,
                                            struct sk_buff *skb)
 {
-       bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), skb);
-}
-
-static inline struct gnet_stats_queue *
-tcf_action_get_qstats(struct tc_action *a)
-{
-       return this_cpu_ptr(a->cpu_qstats);
+       if (likely(a->cpu_bstats)) {
+               bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), skb);
+               return;
+       }
+       spin_lock(&a->tcfa_lock);
+       bstats_update(&a->tcfa_bstats, skb);
+       spin_unlock(&a->tcfa_lock);
 }
 
 static inline void tcf_action_inc_drop_qstats(struct tc_action *a)
 {
-       qstats_drop_inc(this_cpu_ptr(a->cpu_qstats));
+       if (likely(a->cpu_qstats)) {
+               qstats_drop_inc(this_cpu_ptr(a->cpu_qstats));
+               return;
+       }
+       spin_lock(&a->tcfa_lock);
+       qstats_drop_inc(&a->tcfa_qstats);
+       spin_unlock(&a->tcfa_lock);
 }
 
 static inline void tcf_action_inc_overlimit_qstats(struct tc_action *a)
 {
-       qstats_overlimit_inc(this_cpu_ptr(a->cpu_qstats));
+       if (likely(a->cpu_qstats)) {
+               qstats_overlimit_inc(this_cpu_ptr(a->cpu_qstats));
+               return;
+       }
+       spin_lock(&a->tcfa_lock);
+       qstats_overlimit_inc(&a->tcfa_qstats);
+       spin_unlock(&a->tcfa_lock);
 }
 
 void tcf_action_update_stats(struct tc_action *a, u64 bytes, u32 packets,
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index 0638afa2fc3f..f85b88da5216 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -992,14 +992,23 @@ int tcf_action_init(struct net *net, struct tcf_proto 
*tp, struct nlattr *nla,
 void tcf_action_update_stats(struct tc_action *a, u64 bytes, u32 packets,
                             bool drop, bool hw)
 {
-       _bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
+       if (a->cpu_bstats) {
+               _bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
 
-       if (drop)
-               this_cpu_ptr(a->cpu_qstats)->drops += packets;
+               if (drop)
+                       this_cpu_ptr(a->cpu_qstats)->drops += packets;
+
+               if (hw)
+                       _bstats_cpu_update(this_cpu_ptr(a->cpu_bstats_hw),
+                                          bytes, packets);
+               return;
+       }
 
+       _bstats_update(&a->tcfa_bstats, bytes, packets);
+       if (drop)
+               a->tcfa_qstats.drops += packets;
        if (hw)
-               _bstats_cpu_update(this_cpu_ptr(a->cpu_bstats_hw),
-                                  bytes, packets);
+               _bstats_update(&a->tcfa_bstats_hw, bytes, packets);
 }
 EXPORT_SYMBOL(tcf_action_update_stats);
 
-- 
2.21.0