Commit a7855c78 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net: loopback driver cleanup 



loopback driver uses dev->ml_priv to store its percpu stats pointer.
It uses ugly casts "(void __percpu __force *)" to shut up sparse
complains.

Define an union to better document we use ml_priv in loopback driver and
define a lstats field with appropriate types.

Signed-off-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 83180af0

drivers/net/loopback.c

+5 −15
Original line number Diff line number Diff line
@@ -74,7 +74,6 @@ struct pcpu_lstats { 
static netdev_tx_t loopback_xmit(struct sk_buff *skb,

				 struct net_device *dev)

{

	struct pcpu_lstats __percpu *pcpu_lstats;

	struct pcpu_lstats *lb_stats;

	int len;
@@ -83,8 +82,7 @@ static netdev_tx_t loopback_xmit(struct sk_buff *skb, 
	skb->protocol = eth_type_trans(skb, dev);



	/* it's OK to use per_cpu_ptr() because BHs are off */

	pcpu_lstats = (void __percpu __force *)dev->ml_priv;

	lb_stats = this_cpu_ptr(pcpu_lstats);

	lb_stats = this_cpu_ptr(dev->lstats);



	len = skb->len;

	if (likely(netif_rx(skb) == NET_RX_SUCCESS)) {
@@ -101,19 +99,17 @@ static netdev_tx_t loopback_xmit(struct sk_buff *skb, 
static struct rtnl_link_stats64 *loopback_get_stats64(struct net_device *dev,

						      struct rtnl_link_stats64 *stats)

{

	const struct pcpu_lstats __percpu *pcpu_lstats;

	u64 bytes = 0;

	u64 packets = 0;

	u64 drops = 0;

	int i;



	pcpu_lstats = (void __percpu __force *)dev->ml_priv;

	for_each_possible_cpu(i) {

		const struct pcpu_lstats *lb_stats;

		u64 tbytes, tpackets;

		unsigned int start;



		lb_stats = per_cpu_ptr(pcpu_lstats, i);

		lb_stats = per_cpu_ptr(dev->lstats, i);

		do {

			start = u64_stats_fetch_begin(&lb_stats->syncp);

			tbytes = lb_stats->bytes;
@@ -147,22 +143,16 @@ static const struct ethtool_ops loopback_ethtool_ops = { 


static int loopback_dev_init(struct net_device *dev)

{

	struct pcpu_lstats __percpu *lstats;



	lstats = alloc_percpu(struct pcpu_lstats);

	if (!lstats)

	dev->lstats = alloc_percpu(struct pcpu_lstats);

	if (!dev->lstats)

		return -ENOMEM;



	dev->ml_priv = (void __force *)lstats;

	return 0;

}



static void loopback_dev_free(struct net_device *dev)

{

	struct pcpu_lstats __percpu *lstats =

		(void __percpu __force *)dev->ml_priv;



	free_percpu(lstats);

	free_percpu(dev->lstats);

	free_netdev(dev);

}

include/linux/netdevice.h

+4 −2
Original line number Diff line number Diff line
@@ -1050,8 +1050,10 @@ struct net_device { 
#endif



	/* mid-layer private */

	union {

		void				*ml_priv;



		struct pcpu_lstats __percpu	*lstats; /* loopback stats */

	};

	/* GARP */

	struct garp_port	*garp_port;

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