[PATCH net v2 2/4] net: add rx_nohandler stat counter

From: Jarod Wilson
Date: Thu Jan 28 2016 - 10:51:40 EST


This adds an rx_nohandler stat counter, along with a sysfs statistics
node, and copies the counter out via netlink as well.

CC: "David S. Miller" <davem@xxxxxxxxxxxxx>
CC: Eric Dumazet <edumazet@xxxxxxxxxx>
CC: Jiri Pirko <jiri@xxxxxxxxxxxx>
CC: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
CC: Tom Herbert <tom@xxxxxxxxxxxxxxx>
CC: Jay Vosburgh <j.vosburgh@xxxxxxxxx>
CC: Veaceslav Falico <vfalico@xxxxxxxxx>
CC: Andy Gospodarek <gospo@xxxxxxxxxxxxxxxxxxx>
CC: netdev@xxxxxxxxxxxxxxx
Signed-off-by: Jarod Wilson <jarod@xxxxxxxxxx>
---
include/linux/netdevice.h | 3 +++
include/uapi/linux/if_link.h | 4 ++++
net/core/dev.c | 6 +++++-
net/core/net-sysfs.c | 2 ++
net/core/rtnetlink.c | 2 ++
5 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 289c231..78a20ce 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1397,6 +1397,8 @@ enum netdev_priv_flags {
* do not use this in drivers
* @tx_dropped: Dropped packets by core network,
* do not use this in drivers
+ * @rx_nohandler: nohandler dropped packets by core network on
+ * inactive devices, do not use this in drivers
*
* @wireless_handlers: List of functions to handle Wireless Extensions,
* instead of ioctl,
@@ -1611,6 +1613,7 @@ struct net_device {

atomic_long_t rx_dropped;
atomic_long_t tx_dropped;
+ atomic_long_t rx_nohandler;

#ifdef CONFIG_WIRELESS_EXT
const struct iw_handler_def * wireless_handlers;
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index a30b780..d3e90b9 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -35,6 +35,8 @@ struct rtnl_link_stats {
/* for cslip etc */
__u32 rx_compressed;
__u32 tx_compressed;
+
+ __u32 rx_nohandler; /* dropped, no handler found */
};

/* The main device statistics structure */
@@ -68,6 +70,8 @@ struct rtnl_link_stats64 {
/* for cslip etc */
__u64 rx_compressed;
__u64 tx_compressed;
+
+ __u64 rx_nohandler; /* dropped, no handler found */
};

/* The struct should be in sync with struct ifmap */
diff --git a/net/core/dev.c b/net/core/dev.c
index 575a7df..fef2351 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4154,7 +4154,10 @@ ncls:
ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
} else {
drop:
- atomic_long_inc(&skb->dev->rx_dropped);
+ if (!deliver_exact)
+ atomic_long_inc(&skb->dev->rx_dropped);
+ else
+ atomic_long_inc(&skb->dev->rx_nohandler);
kfree_skb(skb);
/* Jamal, now you will not able to escape explaining
* me how you were going to use this. :-)
@@ -7305,6 +7308,7 @@ struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
}
storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
storage->tx_dropped += atomic_long_read(&dev->tx_dropped);
+ storage->rx_nohandler += atomic_long_read(&dev->rx_nohandler);
return storage;
}
EXPORT_SYMBOL(dev_get_stats);
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index b6c8a66..da7dbc2 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -574,6 +574,7 @@ NETSTAT_ENTRY(tx_heartbeat_errors);
NETSTAT_ENTRY(tx_window_errors);
NETSTAT_ENTRY(rx_compressed);
NETSTAT_ENTRY(tx_compressed);
+NETSTAT_ENTRY(rx_nohandler);

static struct attribute *netstat_attrs[] = {
&dev_attr_rx_packets.attr,
@@ -599,6 +600,7 @@ static struct attribute *netstat_attrs[] = {
&dev_attr_tx_window_errors.attr,
&dev_attr_rx_compressed.attr,
&dev_attr_tx_compressed.attr,
+ &dev_attr_rx_nohandler.attr,
NULL
};

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index d735e85..20d7135 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -804,6 +804,8 @@ static void copy_rtnl_link_stats(struct rtnl_link_stats *a,

a->rx_compressed = b->rx_compressed;
a->tx_compressed = b->tx_compressed;
+
+ a->rx_nohandler = b->rx_nohandler;
}

static void copy_rtnl_link_stats64(void *v, const struct rtnl_link_stats64 *b)
--
1.8.3.1