kernel: make ledtrig-netdev use a work queue for updates
This fixes hangs in igb that happen if the update call interrupts an already existing dev_get_stats call. In that case the calling CPU deadlocks because it's trying to acquire the same spinlock recursively. Signed-off-by: Felix Fietkau <nbd@nbd.name>
This commit is contained in:
		| @@ -70,7 +70,7 @@ | ||||
| struct led_netdev_data { | ||||
| 	spinlock_t lock; | ||||
|  | ||||
| 	struct timer_list timer; | ||||
| 	struct delayed_work work; | ||||
| 	struct notifier_block notifier; | ||||
|  | ||||
| 	struct led_classdev *led_cdev; | ||||
| @@ -91,7 +91,7 @@ static void set_baseline_state(struct led_netdev_data *trigger_data) | ||||
| 		led_set_brightness(trigger_data->led_cdev, LED_OFF); | ||||
|  | ||||
| 	if ((trigger_data->mode & (MODE_TX | MODE_RX)) != 0 && trigger_data->link_up) | ||||
| 		mod_timer(&trigger_data->timer, jiffies + trigger_data->interval); | ||||
| 		schedule_delayed_work(&trigger_data->work, trigger_data->interval); | ||||
| } | ||||
|  | ||||
| static ssize_t led_device_name_show(struct device *dev, | ||||
| @@ -116,8 +116,9 @@ static ssize_t led_device_name_store(struct device *dev, | ||||
| 	if (size < 0 || size >= IFNAMSIZ) | ||||
| 		return -EINVAL; | ||||
|  | ||||
| 	cancel_delayed_work_sync(&trigger_data->work); | ||||
|  | ||||
| 	spin_lock_bh(&trigger_data->lock); | ||||
| 	del_timer_sync(&trigger_data->timer); | ||||
|  | ||||
| 	strcpy(trigger_data->device_name, buf); | ||||
| 	if (size > 0 && trigger_data->device_name[size-1] == '\n') | ||||
| @@ -201,11 +202,10 @@ static ssize_t led_mode_store(struct device *dev, | ||||
| 	if (new_mode == -1) | ||||
| 		return -EINVAL; | ||||
|  | ||||
| 	cancel_delayed_work_sync(&trigger_data->work); | ||||
|  | ||||
| 	spin_lock_bh(&trigger_data->lock); | ||||
| 	del_timer_sync(&trigger_data->timer); | ||||
|  | ||||
| 	trigger_data->mode = new_mode; | ||||
|  | ||||
| 	set_baseline_state(trigger_data); | ||||
| 	spin_unlock_bh(&trigger_data->lock); | ||||
|  | ||||
| @@ -242,11 +242,10 @@ static ssize_t led_interval_store(struct device *dev, | ||||
|  | ||||
| 	/* impose some basic bounds on the timer interval */ | ||||
| 	if (count == size && value >= 5 && value <= 10000) { | ||||
| 		cancel_delayed_work_sync(&trigger_data->work); | ||||
|  | ||||
| 		spin_lock_bh(&trigger_data->lock); | ||||
| 		del_timer_sync(&trigger_data->timer); | ||||
|  | ||||
| 		trigger_data->interval = msecs_to_jiffies(value); | ||||
|  | ||||
| 		set_baseline_state(trigger_data); /* resets timer */ | ||||
| 		spin_unlock_bh(&trigger_data->lock); | ||||
|  | ||||
| @@ -268,13 +267,13 @@ static int netdev_trig_notify(struct notifier_block *nb, | ||||
| 	if (evt != NETDEV_UP && evt != NETDEV_DOWN && evt != NETDEV_CHANGE && evt != NETDEV_REGISTER && evt != NETDEV_UNREGISTER && evt != NETDEV_CHANGENAME) | ||||
| 		return NOTIFY_DONE; | ||||
|  | ||||
| 	cancel_delayed_work_sync(&trigger_data->work); | ||||
|  | ||||
| 	spin_lock_bh(&trigger_data->lock); | ||||
|  | ||||
| 	if (strcmp(dev->name, trigger_data->device_name)) | ||||
| 		goto done; | ||||
|  | ||||
| 	del_timer_sync(&trigger_data->timer); | ||||
|  | ||||
| 	if (evt == NETDEV_REGISTER || evt == NETDEV_CHANGENAME) { | ||||
| 		if (trigger_data->net_dev != NULL) | ||||
| 			dev_put(trigger_data->net_dev); | ||||
| @@ -302,9 +301,9 @@ done: | ||||
| } | ||||
|  | ||||
| /* here's the real work! */ | ||||
| static void netdev_trig_timer(unsigned long arg) | ||||
| static void netdev_trig_work(struct work_struct *work) | ||||
| { | ||||
| 	struct led_netdev_data *trigger_data = (struct led_netdev_data *)arg; | ||||
| 	struct led_netdev_data *trigger_data = container_of(work, struct led_netdev_data, work.work); | ||||
| 	struct rtnl_link_stats64 *dev_stats; | ||||
| 	unsigned new_activity; | ||||
| 	struct rtnl_link_stats64 temp; | ||||
| @@ -343,7 +342,7 @@ static void netdev_trig_timer(unsigned long arg) | ||||
| 	} | ||||
|  | ||||
| 	trigger_data->last_activity = new_activity; | ||||
| 	mod_timer(&trigger_data->timer, jiffies + trigger_data->interval); | ||||
| 	schedule_delayed_work(&trigger_data->work, trigger_data->interval); | ||||
| } | ||||
|  | ||||
| static void netdev_trig_activate(struct led_classdev *led_cdev) | ||||
| @@ -360,7 +359,7 @@ static void netdev_trig_activate(struct led_classdev *led_cdev) | ||||
| 	trigger_data->notifier.notifier_call = netdev_trig_notify; | ||||
| 	trigger_data->notifier.priority = 10; | ||||
|  | ||||
| 	setup_timer(&trigger_data->timer, netdev_trig_timer, (unsigned long) trigger_data); | ||||
| 	INIT_DELAYED_WORK(&trigger_data->work, netdev_trig_work); | ||||
|  | ||||
| 	trigger_data->led_cdev = led_cdev; | ||||
| 	trigger_data->net_dev = NULL; | ||||
| @@ -406,8 +405,9 @@ static void netdev_trig_deactivate(struct led_classdev *led_cdev) | ||||
| 		device_remove_file(led_cdev->dev, &dev_attr_mode); | ||||
| 		device_remove_file(led_cdev->dev, &dev_attr_interval); | ||||
|  | ||||
| 		cancel_delayed_work_sync(&trigger_data->work); | ||||
|  | ||||
| 		spin_lock_bh(&trigger_data->lock); | ||||
| 		del_timer_sync(&trigger_data->timer); | ||||
|  | ||||
| 		if (trigger_data->net_dev) { | ||||
| 			dev_put(trigger_data->net_dev); | ||||
|   | ||||
		Reference in New Issue
	
	Block a user
	 Felix Fietkau
					Felix Fietkau