flow_offload: add process to update action stats from hardware

When collecting stats for actions update them using both
hardware and software counters.

Stats update process should not run in context of preempt_disable.

Signed-off-by: Baowen Zheng <baowen.zheng@corigine.com>
Signed-off-by: Louis Peens <louis.peens@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 45 insertions, 8 deletions

diff --git a/include/net/act_api.h b/include/net/act_api.h
index 15c6a881817d..20104dfdd57c 100644
--- a/include/net/act_api.h
+++ b/include/net/act_api.h
@@ -253,6 +253,7 @@ void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets,
 			     u64 drops, bool hw);
 int tcf_action_copy_stats(struct sk_buff *, struct tc_action *, int);
 
+int tcf_action_update_hw_stats(struct tc_action *action);
 int tcf_action_check_ctrlact(int action, struct tcf_proto *tp,
 			     struct tcf_chain **handle,
 			     struct netlink_ext_ack *newchain);
diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h
index efdfab8eb00c..337a3ebb4666 100644
--- a/include/net/pkt_cls.h
+++ b/include/net/pkt_cls.h
@@ -273,18 +273,20 @@ tcf_exts_hw_stats_update(const struct tcf_exts *exts,
 #ifdef CONFIG_NET_CLS_ACT
 	int i;
 
-	preempt_disable();
-
 	for (i = 0; i < exts->nr_actions; i++) {
 		struct tc_action *a = exts->actions[i];
 
-		tcf_action_stats_update(a, bytes, packets, drops,
-					lastuse, true);
-		a->used_hw_stats = used_hw_stats;
-		a->used_hw_stats_valid = used_hw_stats_valid;
-	}
+		/* if stats from hw, just skip */
+		if (tcf_action_update_hw_stats(a)) {
+			preempt_disable();
+			tcf_action_stats_update(a, bytes, packets, drops,
+						lastuse, true);
+			preempt_enable();
 
-	preempt_enable();
+			a->used_hw_stats = used_hw_stats;
+			a->used_hw_stats_valid = used_hw_stats_valid;
+		}
+	}
 #endif
 }
 
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index d446e89ececc..f9186f283488 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -246,6 +246,37 @@ fl_err:
 	return err;
 }
 
+int tcf_action_update_hw_stats(struct tc_action *action)
+{
+	struct flow_offload_action fl_act = {};
+	int err;
+
+	if (!tc_act_in_hw(action))
+		return -EOPNOTSUPP;
+
+	err = offload_action_init(&fl_act, action, FLOW_ACT_STATS, NULL);
+	if (err)
+		return err;
+
+	err = tcf_action_offload_cmd(&fl_act, NULL, NULL);
+	if (!err) {
+		preempt_disable();
+		tcf_action_stats_update(action, fl_act.stats.bytes,
+					fl_act.stats.pkts,
+					fl_act.stats.drops,
+					fl_act.stats.lastused,
+					true);
+		preempt_enable();
+		action->used_hw_stats = fl_act.stats.used_hw_stats;
+		action->used_hw_stats_valid = true;
+	} else {
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(tcf_action_update_hw_stats);
+
 static int tcf_action_offload_del(struct tc_action *action)
 {
 	struct flow_offload_action fl_act = {};
@@ -1318,6 +1349,9 @@ int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
 	if (p == NULL)
 		goto errout;
 
+	/* update hw stats for this action */
+	tcf_action_update_hw_stats(p);
+
 	/* compat_mode being true specifies a call that is supposed
 	 * to add additional backward compatibility statistic TLVs.
 	 */