Re: [patch net-next 3/4] net: core: add SW stats to if_stats_msg

On May 12, 2016, at 12:59 PM, Jiri Pirko [off-list ref] wrote:

From: Nogah Frankel <redacted>

If there is a dedicated ndo to return SW stats - use
it. Otherwise (indicates that there is no HW stats) use
the default stats ndo.
Return results under IFLA_STATS_LINK_SW_64.

Signed-off-by: Nogah Frankel <redacted>
Reviewed-by: Ido Schimmel <redacted>
Signed-off-by: Jiri Pirko <redacted>
---
include/uapi/linux/if_link.h |  1 +
net/core/rtnetlink.c         | 35 +++++++++++++++++++++++++++++------
2 files changed, 30 insertions(+), 6 deletions(-)

diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 98175e7..fcfb944 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h

@@ -823,6 +823,7 @@ enum {

	IFLA_STATS_UNSPEC, /* also used as 64bit pad attribute */
	IFLA_STATS_LINK_64,
	IFLA_STATS_LINK_XSTATS,
+	IFLA_STATS_LINK_SW_64,
	__IFLA_STATS_MAX,
};

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index a127d67..f8b12e4 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c

@@ -3481,6 +3481,9 @@ static int rtnl_fill_statsinfo(struct sk_buff *skb, struct net_device *dev,

	struct nlmsghdr *nlh;
	struct nlattr *attr;
	int s_prividx = *prividx;
+	struct rtnl_link_stats64 *sp;
+	struct rtnl_link_stats64 *stats64_sp = 0;

+	int err;

	ASSERT_RTNL();

@@ -3493,24 +3496,20 @@ static int rtnl_fill_statsinfo(struct sk_buff *skb, struct net_device *dev,

	ifsm->filter_mask = filter_mask;

	if (stats_attr_valid(filter_mask, IFLA_STATS_LINK_64, *idxattr)) {
-		struct rtnl_link_stats64 *sp;
-
		attr = nla_reserve_64bit(skb, IFLA_STATS_LINK_64,
					 sizeof(struct rtnl_link_stats64),
					 IFLA_STATS_UNSPEC);
		if (!attr)
			goto nla_put_failure;

-		sp = nla_data(attr);
-		dev_get_stats(dev, sp);
+		stats64_sp = nla_data(attr);
+		dev_get_stats(dev, stats64_sp);
	}

	if (stats_attr_valid(filter_mask, IFLA_STATS_LINK_XSTATS, *idxattr)) {
		const struct rtnl_link_ops *ops = dev->rtnl_link_ops;

		if (ops && ops->fill_linkxstats) {
-			int err;
-
			*idxattr = IFLA_STATS_LINK_XSTATS;
			attr = nla_nest_start(skb,
					      IFLA_STATS_LINK_XSTATS);

@@ -3525,6 +3524,27 @@ static int rtnl_fill_statsinfo(struct sk_buff *skb, struct net_device *dev,

		}
	}

+	if (stats_attr_valid(filter_mask, IFLA_STATS_LINK_SW_64, *idxattr)) {
+		attr = nla_reserve_64bit(skb, IFLA_STATS_LINK_SW_64,
+					 sizeof(struct rtnl_link_stats64),
+					 IFLA_STATS_UNSPEC);
+		if (!attr)
+			goto nla_put_failure;
+
+		sp = nla_data(attr);
+		err = dev_get_sw_stats(dev, sp);
+		if (err) {
+			/* if err it means there is no dedicated ndo to
+			 * get SW stats - so it is returned by the default
+			 * stats ndo
+			 */
+			if (stats64_sp)
+				copy_rtnl_link_stats64(sp, stats64_sp);
+			else
+				dev_get_stats(dev, sp);
+		}
+	}
+
	nlmsg_end(skb, nlh);

	return 0;

@@ -3541,6 +3561,7 @@ nla_put_failure:

static const struct nla_policy ifla_stats_policy[IFLA_STATS_MAX + 1] = {
	[IFLA_STATS_LINK_64]	= { .len = sizeof(struct rtnl_link_stats64) },
+	[IFLA_STATS_LINK_SW_64] = { .len = sizeof(struct rtnl_link_stats64) },
};

static size_t if_nlmsg_stats_size(const struct net_device *dev,

@@ -3550,6 +3571,8 @@ static size_t if_nlmsg_stats_size(const struct net_device *dev,

	if (stats_attr_valid(filter_mask, IFLA_STATS_LINK_64, 0))
		size += nla_total_size_64bit(sizeof(struct rtnl_link_stats64));
+	if (stats_attr_valid(filter_mask, IFLA_STATS_LINK_SW_64, 0))
+		size += nla_total_size_64bit(sizeof(struct rtnl_link_stats64));

	if (stats_attr_valid(filter_mask, IFLA_STATS_LINK_XSTATS, 0)) {
		const struct rtnl_link_ops *ops = dev->rtnl_link_ops;
-- 
2.5.5