Commit b7ecc1de authored by Antoine Tenart's avatar Antoine Tenart Committed by Jakub Kicinski
Browse files

net-sysfs: move queue attribute groups outside the default groups 



Rx/tx queues embed their own kobject for registering their per-queue
sysfs files. The issue is they're using the kobject default groups for
this and entirely rely on the kobject refcounting for releasing their
sysfs paths.

In order to remove rtnl_trylock calls we need sysfs files not to rely on
their associated kobject refcounting for their release. Thus we here
move queues sysfs files from the kobject default groups to their own
groups which can be removed separately.

Signed-off-by: default avatarAntoine Tenart <atenart@kernel.org>
Link: https://patch.msgid.link/20250204170314.146022-3-atenart@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 79c61899

include/linux/netdevice.h

+1 −0
Original line number Diff line number Diff line
@@ -658,6 +658,7 @@ struct netdev_queue { 
	struct Qdisc __rcu	*qdisc_sleeping;

#ifdef CONFIG_SYSFS

	struct kobject		kobj;

	const struct attribute_group	**groups;

#endif

	unsigned long		tx_maxrate;

	/*

include/net/netdev_rx_queue.h

+1 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ struct netdev_rx_queue { 
	struct rps_dev_flow_table __rcu	*rps_flow_table;

#endif

	struct kobject			kobj;

	const struct attribute_group	**groups;

	struct net_device		*dev;

	netdevice_tracker		dev_tracker;

net/core/net-sysfs.c

+21 −6
Original line number Diff line number Diff line
@@ -1188,7 +1188,6 @@ static void rx_queue_get_ownership(const struct kobject *kobj, 
static const struct kobj_type rx_queue_ktype = {

	.sysfs_ops = &rx_queue_sysfs_ops,

	.release = rx_queue_release,

	.default_groups = rx_queue_default_groups,

	.namespace = rx_queue_namespace,

	.get_ownership = rx_queue_get_ownership,

};
@@ -1222,20 +1221,27 @@ static int rx_queue_add_kobject(struct net_device *dev, int index) 
	if (error)

		goto err;



	queue->groups = rx_queue_default_groups;

	error = sysfs_create_groups(kobj, queue->groups);

	if (error)

		goto err;



	if (dev->sysfs_rx_queue_group) {

		error = sysfs_create_group(kobj, dev->sysfs_rx_queue_group);

		if (error)

			goto err;

			goto err_default_groups;

	}



	error = rx_queue_default_mask(dev, queue);

	if (error)

		goto err;

		goto err_default_groups;



	kobject_uevent(kobj, KOBJ_ADD);



	return error;



err_default_groups:

	sysfs_remove_groups(kobj, queue->groups);

err:

	kobject_put(kobj);

	return error;
@@ -1280,12 +1286,14 @@ net_rx_queue_update_kobjects(struct net_device *dev, int old_num, int new_num) 
	}



	while (--i >= new_num) {

		struct kobject *kobj = &dev->_rx[i].kobj;

		struct netdev_rx_queue *queue = &dev->_rx[i];

		struct kobject *kobj = &queue->kobj;



		if (!refcount_read(&dev_net(dev)->ns.count))

			kobj->uevent_suppress = 1;

		if (dev->sysfs_rx_queue_group)

			sysfs_remove_group(kobj, dev->sysfs_rx_queue_group);

		sysfs_remove_groups(kobj, queue->groups);

		kobject_put(kobj);

	}
@@ -1872,7 +1880,6 @@ static void netdev_queue_get_ownership(const struct kobject *kobj, 
static const struct kobj_type netdev_queue_ktype = {

	.sysfs_ops = &netdev_queue_sysfs_ops,

	.release = netdev_queue_release,

	.default_groups = netdev_queue_default_groups,

	.namespace = netdev_queue_namespace,

	.get_ownership = netdev_queue_get_ownership,

};
@@ -1902,15 +1909,22 @@ static int netdev_queue_add_kobject(struct net_device *dev, int index) 
	if (error)

		goto err;



	queue->groups = netdev_queue_default_groups;

	error = sysfs_create_groups(kobj, queue->groups);

	if (error)

		goto err;



	if (netdev_uses_bql(dev)) {

		error = sysfs_create_group(kobj, &dql_group);

		if (error)

			goto err;

			goto err_default_groups;

	}



	kobject_uevent(kobj, KOBJ_ADD);

	return 0;



err_default_groups:

	sysfs_remove_groups(kobj, queue->groups);

err:

	kobject_put(kobj);

	return error;
@@ -1965,6 +1979,7 @@ netdev_queue_update_kobjects(struct net_device *dev, int old_num, int new_num) 
		if (netdev_uses_bql(dev))

			sysfs_remove_group(&queue->kobj, &dql_group);



		sysfs_remove_groups(&queue->kobj, queue->groups);

		kobject_put(&queue->kobj);

	}