From d7a68e564e29bcd1c70d76d9e2f65591e6183f46 Mon Sep 17 00:00:00 2001
From: Zhengchao Shao <shaozhengchao@huawei.com>
Date: Wed, 21 Sep 2022 10:41:04 +0800
Subject: [PATCH] net/sched: sch_api: add helper for tc qdisc walker stats dump
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The walk implementation of most qdisc class modules is basically the
same. That is, the values of count and skip are checked first. If
count is greater than or equal to skip, the registered fn function is
executed. Otherwise, increase the value of count. So we can reconstruct
them.

Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 include/net/pkt_sched.h | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/include/net/pkt_sched.h b/include/net/pkt_sched.h
index 29f65632ebc5..2ff80cd04c5c 100644
--- a/include/net/pkt_sched.h
+++ b/include/net/pkt_sched.h
@@ -222,4 +222,17 @@ static inline struct tc_skb_cb *tc_skb_cb(const struct sk_buff *skb)
 	return cb;
 }
 
+static inline bool tc_qdisc_stats_dump(struct Qdisc *sch,
+				       unsigned long cl,
+				       struct qdisc_walker *arg)
+{
+	if (arg->count >= arg->skip && arg->fn(sch, cl, arg) < 0) {
+		arg->stop = 1;
+		return false;
+	}
+
+	arg->count++;
+	return true;
+}
+
 #endif