Commit f383ced2 authored by Eric Dumazet's avatar Eric Dumazet Committed by Jakub Kicinski
Browse files

vlan: use xarray iterator to implement /proc/net/vlan/config 



Adopt net->dev_by_index as I did in commit 0e0939c0
("net-procfs: use xarray iterator to implement /proc/net/dev")

Not only this removes quadratic behavior, it also makes sure
an existing vlan device is always visible in the dump,
regardless of concurrent net->dev_base_head changes.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Reviewed-by: default avatarJakub Kicinski <kuba@kernel.org>
Reviewed-by: default avatarIdo Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/20240211214404.1882191-2-edumazet@google.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent bed90b06

net/8021q/vlanproc.c

+16 −30
Original line number Diff line number Diff line
@@ -163,48 +163,34 @@ void vlan_proc_rem_dev(struct net_device *vlandev) 
 * The following few functions build the content of /proc/net/vlan/config

 */



/* start read of /proc/net/vlan/config */

static void *vlan_seq_start(struct seq_file *seq, loff_t *pos)

	__acquires(rcu)

static void *vlan_seq_from_index(struct seq_file *seq, loff_t *pos)

{

	unsigned long ifindex = *pos;

	struct net_device *dev;

	struct net *net = seq_file_net(seq);

	loff_t i = 1;



	rcu_read_lock();

	if (*pos == 0)

		return SEQ_START_TOKEN;



	for_each_netdev_rcu(net, dev) {

	for_each_netdev_dump(seq_file_net(seq), dev, ifindex) {

		if (!is_vlan_dev(dev))

			continue;



		if (i++ == *pos)

		*pos = dev->ifindex;

		return dev;

	}



	return NULL;

}



static void *vlan_seq_next(struct seq_file *seq, void *v, loff_t *pos)

static void *vlan_seq_start(struct seq_file *seq, loff_t *pos)

	__acquires(rcu)

{

	struct net_device *dev;

	struct net *net = seq_file_net(seq);



	++*pos;



	dev = v;

	if (v == SEQ_START_TOKEN)

		dev = net_device_entry(&net->dev_base_head);



	for_each_netdev_continue_rcu(net, dev) {

		if (!is_vlan_dev(dev))

			continue;

	rcu_read_lock();

	if (*pos == 0)

		return SEQ_START_TOKEN;



		return dev;

	return vlan_seq_from_index(seq, pos);

}



	return NULL;

static void *vlan_seq_next(struct seq_file *seq, void *v, loff_t *pos)

{

	++*pos;

	return vlan_seq_from_index(seq, pos);

}



static void vlan_seq_stop(struct seq_file *seq, void *v)