Re: [patch net-next v10 2/3] net: core: Add offload stats to if_stats_msg

[Nikolay Aleksandrov]

> On Sep 16, 2016, at 4:05 PM, Jiri Pirko  wrote:
> 
> From: Nogah Frankel 
> 
> Add a nested attribute of offload stats to if_stats_msg
> named IFLA_STATS_LINK_OFFLOAD_XSTATS.
> Under it, add SW stats, meaning stats only per packets that went via
> slowpath to the cpu, named IFLA_OFFLOAD_XSTATS_CPU_HIT.
> 
> Signed-off-by: Nogah Frankel 
> Signed-off-by: Jiri Pirko 
> ---
> include/uapi/linux/if_link.h |   9 
> net/core/rtnetlink.c | 111 +--
> 2 files changed, 116 insertions(+), 4 deletions(-)
> 
> 

Acked-by: Nikolay Aleksandrov 

[patch net-next v10 2/3] net: core: Add offload stats to if_stats_msg

[Jiri Pirko]

From: Nogah Frankel 

Add a nested attribute of offload stats to if_stats_msg
named IFLA_STATS_LINK_OFFLOAD_XSTATS.
Under it, add SW stats, meaning stats only per packets that went via
slowpath to the cpu, named IFLA_OFFLOAD_XSTATS_CPU_HIT.

Signed-off-by: Nogah Frankel 
Signed-off-by: Jiri Pirko 
---
 include/uapi/linux/if_link.h |   9 
 net/core/rtnetlink.c | 111 +--
 2 files changed, 116 insertions(+), 4 deletions(-)

diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 9bf3aec..2351776 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -826,6 +826,7 @@ enum {
IFLA_STATS_LINK_64,
IFLA_STATS_LINK_XSTATS,
IFLA_STATS_LINK_XSTATS_SLAVE,
+   IFLA_STATS_LINK_OFFLOAD_XSTATS,
__IFLA_STATS_MAX,
 };
 
@@ -845,6 +846,14 @@ enum {
 };
 #define LINK_XSTATS_TYPE_MAX (__LINK_XSTATS_TYPE_MAX - 1)
 
+/* These are stats embedded into IFLA_STATS_LINK_OFFLOAD_XSTATS */
+enum {
+   IFLA_OFFLOAD_XSTATS_UNSPEC,
+   IFLA_OFFLOAD_XSTATS_CPU_HIT, /* struct rtnl_link_stats64 */
+   __IFLA_OFFLOAD_XSTATS_MAX
+};
+#define IFLA_OFFLOAD_XSTATS_MAX (__IFLA_OFFLOAD_XSTATS_MAX - 1)
+
 /* XDP section */
 
 enum {
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 937e459..0dbae42 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -3577,6 +3577,91 @@ static bool stats_attr_valid(unsigned int mask, int 
attrid, int idxattr)
   (!idxattr || idxattr == attrid);
 }
 
+#define IFLA_OFFLOAD_XSTATS_FIRST (IFLA_OFFLOAD_XSTATS_UNSPEC + 1)
+static int rtnl_get_offload_stats_attr_size(int attr_id)
+{
+   switch (attr_id) {
+   case IFLA_OFFLOAD_XSTATS_CPU_HIT:
+   return sizeof(struct rtnl_link_stats64);
+   }
+
+   return 0;
+}
+
+static int rtnl_get_offload_stats(struct sk_buff *skb, struct net_device *dev,
+ int *prividx)
+{
+   struct nlattr *attr = NULL;
+   int attr_id, size;
+   void *attr_data;
+   int err;
+
+   if (!(dev->netdev_ops && dev->netdev_ops->ndo_has_offload_stats &&
+ dev->netdev_ops->ndo_get_offload_stats))
+   return -ENODATA;
+
+   for (attr_id = IFLA_OFFLOAD_XSTATS_FIRST;
+attr_id <= IFLA_OFFLOAD_XSTATS_MAX; attr_id++) {
+   if (attr_id < *prividx)
+   continue;
+
+   size = rtnl_get_offload_stats_attr_size(attr_id);
+   if (!size)
+   continue;
+
+   if (!dev->netdev_ops->ndo_has_offload_stats(attr_id))
+   continue;
+
+   attr = nla_reserve_64bit(skb, attr_id, size,
+IFLA_OFFLOAD_XSTATS_UNSPEC);
+   if (!attr)
+   goto nla_put_failure;
+
+   attr_data = nla_data(attr);
+   memset(attr_data, 0, size);
+   err = dev->netdev_ops->ndo_get_offload_stats(attr_id, dev,
+attr_data);
+   if (err)
+   goto get_offload_stats_failure;
+   }
+
+   if (!attr)
+   return -ENODATA;
+
+   *prividx = 0;
+   return 0;
+
+nla_put_failure:
+   err = -EMSGSIZE;
+get_offload_stats_failure:
+   *prividx = attr_id;
+   return err;
+}
+
+static int rtnl_get_offload_stats_size(const struct net_device *dev)
+{
+   int nla_size = 0;
+   int attr_id;
+   int size;
+
+   if (!(dev->netdev_ops && dev->netdev_ops->ndo_has_offload_stats &&
+ dev->netdev_ops->ndo_get_offload_stats))
+   return 0;
+
+   for (attr_id = IFLA_OFFLOAD_XSTATS_FIRST;
+attr_id <= IFLA_OFFLOAD_XSTATS_MAX; attr_id++) {
+   if (!dev->netdev_ops->ndo_has_offload_stats(attr_id))
+   continue;
+   size = rtnl_get_offload_stats_attr_size(attr_id);
+   nla_size += nla_total_size_64bit(size);
+   }
+
+   if (nla_size != 0)
+   nla_size += nla_total_size(0);
+
+   return nla_size;
+}
+
 static int rtnl_fill_statsinfo(struct sk_buff *skb, struct net_device *dev,
   int type, u32 pid, u32 seq, u32 change,
   unsigned int flags, unsigned int filter_mask,
@@ -3586,6 +3671,7 @@ static int rtnl_fill_statsinfo(struct sk_buff *skb, 
struct net_device *dev,
struct nlmsghdr *nlh;
struct nlattr *attr;
int s_prividx = *prividx;
+   int err;
 
ASSERT_RTNL();
 
@@ -3614,8 +3700,6 @@ static int rtnl_fill_statsinfo(struct sk_buff *skb, 
struct net_device *dev,
const struct rtnl_link_ops *ops = dev->rtnl_link_ops;
 
if (ops && ops->fill_linkxstats) {
-   int err;
-
*idxattr =