net: watchdog: add net device refcount tracker

Add a netdevice_tracker inside struct net_device, to track
the self reference when a device has an active watchdog timer.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Eric Dumazet 2021-12-06 17:30:30 -08:00 committed by Jakub Kicinski
parent b2dcdc7f73
commit f12bf6f3f9
2 changed files with 8 additions and 4 deletions

View File

@ -1951,6 +1951,7 @@ enum netdev_ml_priv_type {
*
* @dev_addr_shadow: Copy of @dev_addr to catch direct writes.
* @linkwatch_dev_tracker: refcount tracker used by linkwatch.
* @watchdog_dev_tracker: refcount tracker used by watchdog.
*
* FIXME: cleanup struct net_device such that network protocol info
* moves out.
@ -2282,6 +2283,7 @@ struct net_device {
u8 dev_addr_shadow[MAX_ADDR_LEN];
netdevice_tracker linkwatch_dev_tracker;
netdevice_tracker watchdog_dev_tracker;
};
#define to_net_dev(d) container_of(d, struct net_device, dev)

View File

@ -499,6 +499,7 @@ EXPORT_SYMBOL(netif_tx_unlock);
static void dev_watchdog(struct timer_list *t)
{
struct net_device *dev = from_timer(dev, t, watchdog_timer);
bool release = true;
spin_lock(&dev->tx_global_lock);
if (!qdisc_tx_is_noop(dev)) {
@ -534,12 +535,13 @@ static void dev_watchdog(struct timer_list *t)
if (!mod_timer(&dev->watchdog_timer,
round_jiffies(jiffies +
dev->watchdog_timeo)))
dev_hold(dev);
release = false;
}
}
spin_unlock(&dev->tx_global_lock);
dev_put(dev);
if (release)
dev_put_track(dev, &dev->watchdog_dev_tracker);
}
void __netdev_watchdog_up(struct net_device *dev)
@ -549,7 +551,7 @@ void __netdev_watchdog_up(struct net_device *dev)
dev->watchdog_timeo = 5*HZ;
if (!mod_timer(&dev->watchdog_timer,
round_jiffies(jiffies + dev->watchdog_timeo)))
dev_hold(dev);
dev_hold_track(dev, &dev->watchdog_dev_tracker, GFP_ATOMIC);
}
}
EXPORT_SYMBOL_GPL(__netdev_watchdog_up);
@ -563,7 +565,7 @@ static void dev_watchdog_down(struct net_device *dev)
{
netif_tx_lock_bh(dev);
if (del_timer(&dev->watchdog_timer))
dev_put(dev);
dev_put_track(dev, &dev->watchdog_dev_tracker);
netif_tx_unlock_bh(dev);
}