[patch net-next 2/4] rtnetlink: add HW/SW stats distinction in rtnl_fill_stats

[Jiri Pirko]

From: Nogah Frankel <nog...@mellanox.com>

Since hardware stats are now returned by default, add a way to
query only software stats.
They are saved in IFLA_SW_STATS64.
(This option is valid only if the driver return HW stats in the
default ndo stats)

Signed-off-by: Nogah Frankel <nog...@mellanox.com>
Reviewed-by: Ido Schimmel <ido...@mellanox.com>
Signed-off-by: Jiri Pirko <j...@mellanox.com>
---
 include/uapi/linux/if_link.h |  1 +
 net/core/rtnetlink.c         | 20 ++++++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index bb36bd5..98175e7 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -156,6 +156,7 @@ enum {
        IFLA_GSO_MAX_SEGS,
        IFLA_GSO_MAX_SIZE,
        IFLA_PAD,
+       IFLA_SW_STATS64,
        __IFLA_MAX
 };
 
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index d69c464..a127d67 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1046,20 +1046,40 @@ static int rtnl_phys_switch_id_fill(struct sk_buff 
*skb, struct net_device *dev)
        return 0;
 }
 
+static void copy_rtnl_link_stats64(void *v, const struct rtnl_link_stats64 *b)
+{
+       memcpy(v, b, sizeof(*b));
+}
+
 static noinline_for_stack int rtnl_fill_stats(struct sk_buff *skb,
                                              struct net_device *dev)
 {
+       struct rtnl_link_stats64 sw_stats;
        struct rtnl_link_stats64 *sp;
        struct nlattr *attr;
+       int err;
 
        attr = nla_reserve_64bit(skb, IFLA_STATS64,
                                 sizeof(struct rtnl_link_stats64), IFLA_PAD);
+
        if (!attr)
                return -EMSGSIZE;
 
        sp = nla_data(attr);
        dev_get_stats(dev, sp);
 
+       err = dev_get_sw_stats(dev, &sw_stats);
+       if (!err) {
+               attr = nla_reserve_64bit(skb, IFLA_SW_STATS64,
+                                        sizeof(struct rtnl_link_stats64),
+                                        IFLA_PAD);
+
+               if (!attr)
+                       return -EMSGSIZE;
+
+               copy_rtnl_link_stats64(nla_data(attr), &sw_stats);
+       }
+
        attr = nla_reserve(skb, IFLA_STATS,
                           sizeof(struct rtnl_link_stats));
        if (!attr)
-- 
2.5.5