Merge branch 'mlxsw-avoid-non-tracker-helpers-when-holding-and-putting-netdevices'

Merge branch 'mlxsw-avoid-non-tracker-helpers-when-holding-and-putting-netdevices'

Petr Machata says:

====================
mlxsw: Avoid non-tracker helpers when holding and putting netdevices

Using the tracking helpers, netdev_hold() and netdev_put(), makes it easier
to debug netdevice refcount imbalances when CONFIG_NET_DEV_REFCNT_TRACKER
is enabled. For example, the following traceback shows the callpath to the
point of an outstanding hold that was never put:

    unregister_netdevice: waiting for swp3 to become free. Usage count = 6
    ref_tracker: eth%d@ffff888123c9a580 has 1/5 users at
	mlxsw_sp_switchdev_event+0x6bd/0xcc0 [mlxsw_spectrum]
	notifier_call_chain+0xbf/0x3b0
	atomic_notifier_call_chain+0x78/0x200
	br_switchdev_fdb_notify+0x25f/0x2c0 [bridge]
	fdb_notify+0x16a/0x1a0 [bridge]
	[...]

In this patchset, get rid of all non-ref-tracking helpers in mlxsw.

- Patch #1 drops two functions that are not used anymore, but contain
  dev_hold() / dev_put() calls.

- Patch #2 avoids taking a reference in one function which is called
  under RTNL.

- The remaining patches convert individual hold/put sites one by one
  from trackerless to tracker-enabled.

Suggested-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/netdev/4c056da27c19d95ffeaba5acf1427ecadfc3f94c.camel@redhat.com/
====================

Link: https://lore.kernel.org/r/cover.1690471774.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>