2010-11-29 02:34:36

by Eric Cooper

[permalink] [raw]
Subject: [PATCH v2] add netdev led trigger

Add a netdev LED trigger for all Blinkenlights lovers...
Originally taken from https://dev.openwrt.org/ticket/2776
Slightly updated for 2.6.24 by Mickey Lauer <[email protected]>
and for 2.6.36 by Eric Cooper <[email protected]>

Signed-off-by: Eric Cooper <[email protected]>
---
Changes in v2:
- Use individual entries for link, transmit, and receive;
each can be "enabled" or "disabled"
- Use strict_strtoul instead of simple_strtoul
- Add descriptions to Documentation/ABI/testing/sysfs-class-led

Documentation/ABI/testing/sysfs-class-led | 64 ++++
drivers/leds/Kconfig | 7 +
drivers/leds/Makefile | 1 +
drivers/leds/ledtrig-netdev.c | 475 +++++++++++++++++++++++++++++
4 files changed, 547 insertions(+), 0 deletions(-)
create mode 100644 drivers/leds/ledtrig-netdev.c

diff --git a/Documentation/ABI/testing/sysfs-class-led b/Documentation/ABI/testing/sysfs-class-led
index 9e4541d..0b03863 100644
--- a/Documentation/ABI/testing/sysfs-class-led
+++ b/Documentation/ABI/testing/sysfs-class-led
@@ -26,3 +26,67 @@ Description:
scheduler is chosen. Trigger specific parameters can appear in
/sys/class/leds/<led> once a given trigger is selected.

+What: /sys/class/leds/<led>/device_name
+Date: November 2010
+KernelVersion: 2.6.37
+Contact: Eric Cooper <[email protected]>
+Description:
+ Network device name to monitor when trigger is set to "netdev".
+
+What: /sys/class/leds/<led>/interval
+Date: November 2010
+KernelVersion: 2.6.37
+Contact: Eric Cooper <[email protected]>
+Description:
+ Duration of LED blink in milliseconds when trigger is set to
+ "netdev".
+
+What: /sys/class/leds/<led>/link
+Date: November 2010
+KernelVersion: 2.6.37
+Contact: Eric Cooper <[email protected]>
+Description:
+ When trigger is set to "netdev", this value is either "enabled"
+ or "disabled". If enabled, this LED's normal state reflects
+ whether or not the link for the corresponding network device
+ is up (has carrier).
+
+What: /sys/class/leds/<led>/transmit
+Date: November 2010
+KernelVersion: 2.6.37
+Contact: Eric Cooper <[email protected]>
+Description:
+ When trigger is set to "netdev", this value is either "enabled"
+ or "disabled". If enabled, this LED blinks when data is
+ transmitted on the corresponding network device.
+
+What: /sys/class/leds/<led>/receive
+Date: November 2010
+KernelVersion: 2.6.37
+Contact: Eric Cooper <[email protected]>
+Description:
+ When trigger is set to "netdev", this value is either "enabled"
+ or "disabled". If enabled, this LED blinks when data is
+ received on the corresponding network device.
+
+ Example configurations:
+
+ Simple link status LED:
+ # echo netdev >someled/trigger
+ # echo eth0 >someled/device_name
+ # echo enabled >someled/link
+
+ Ethernet-style link/activity LED:
+ # echo netdev >someled/trigger
+ # echo eth0 >someled/device_name
+ # echo enabled >someled/link
+ # echo enabled >someled/transmit
+ # echo enabled >someled/receive
+
+ Modem-style tx/rx LEDs:
+ # echo netdev >led1/trigger
+ # echo ppp0 >led1/device_name
+ # echo enabled >led1/transmit
+ # echo netdev >led2/trigger
+ # echo ppp0 >led2/device_name
+ # echo enabled >led2/receive
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 77b8fd2..8d81cd0 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -374,6 +374,13 @@ config LEDS_TRIGGER_HEARTBEAT
load average.
If unsure, say Y.

+config LEDS_TRIGGER_NETDEV
+ tristate "LED Network Device Trigger"
+ depends on NET
+ help
+ This allows LEDs to be controlled by network device activity.
+ If unsure, say Y.
+
config LEDS_TRIGGER_BACKLIGHT
tristate "LED backlight Trigger"
help
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index aae6989..a3bb67d 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -49,6 +49,7 @@ obj-$(CONFIG_LEDS_DAC124S085) += leds-dac124s085.o
obj-$(CONFIG_LEDS_TRIGGER_TIMER) += ledtrig-timer.o
obj-$(CONFIG_LEDS_TRIGGER_IDE_DISK) += ledtrig-ide-disk.o
obj-$(CONFIG_LEDS_TRIGGER_HEARTBEAT) += ledtrig-heartbeat.o
+obj-$(CONFIG_LEDS_TRIGGER_NETDEV) += ledtrig-netdev.o
obj-$(CONFIG_LEDS_TRIGGER_BACKLIGHT) += ledtrig-backlight.o
obj-$(CONFIG_LEDS_TRIGGER_GPIO) += ledtrig-gpio.o
obj-$(CONFIG_LEDS_TRIGGER_DEFAULT_ON) += ledtrig-default-on.o
diff --git a/drivers/leds/ledtrig-netdev.c b/drivers/leds/ledtrig-netdev.c
new file mode 100644
index 0000000..eeb5ac8
--- /dev/null
+++ b/drivers/leds/ledtrig-netdev.c
@@ -0,0 +1,475 @@
+/*
+ * LED Kernel Netdev Trigger
+ *
+ * Toggles the LED to reflect the link and traffic state of a named net device
+ *
+ * Copyright 2007 Oliver Jowett <[email protected]>
+ *
+ * Derived from ledtrig-timer.c which is:
+ * Copyright 2005-2006 Openedhand Ltd.
+ * Author: Richard Purdie <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/device.h>
+#include <linux/sysdev.h>
+#include <linux/netdevice.h>
+#include <linux/timer.h>
+#include <linux/ctype.h>
+#include <linux/leds.h>
+#include <linux/version.h>
+#include <net/net_namespace.h>
+
+#include "leds.h"
+
+/*
+ * Configurable sysfs attributes:
+ *
+ * device_name - network device name to monitor
+ *
+ * interval - duration of LED blink, in milliseconds
+ *
+ * Each of the following attributes may be "enabled" or "disabled":
+ *
+ * link - if enabled, the LED's normal state reflects
+ * whether the link is up (has carrier)
+ * transmit - if enabled, the LED blinks on transmitted data
+ * receive - if enabled, the LED blinks on received data
+ *
+ * Some suggestions:
+ *
+ * Simple link status LED:
+ * $ echo netdev >someled/trigger
+ * $ echo eth0 >someled/device_name
+ * $ echo enabled >someled/link
+ *
+ * Ethernet-style link/activity LED:
+ * $ echo netdev >someled/trigger
+ * $ echo eth0 >someled/device_name
+ * $ echo enabled >someled/link
+ * $ echo enabled >someled/transmit
+ * $ echo enabled >someled/receive
+ *
+ * Modem-style tx/rx LEDs:
+ * $ echo netdev >led1/trigger
+ * $ echo ppp0 >led1/device_name
+ * $ echo enabled >led1/transmit
+ * $ echo netdev >led2/trigger
+ * $ echo ppp0 >led2/device_name
+ * $ echo enabled >led2/receive
+ */
+
+#define MODE_LINK 1
+#define MODE_TX 2
+#define MODE_RX 4
+
+struct led_netdev_data {
+ rwlock_t lock;
+
+ struct timer_list timer;
+ struct notifier_block notifier;
+
+ struct led_classdev *led_cdev;
+ struct net_device *net_dev;
+
+ char device_name[IFNAMSIZ];
+ unsigned interval;
+ unsigned mode;
+ unsigned link_up;
+ unsigned last_activity;
+};
+
+static void set_baseline_state(struct led_netdev_data *trigger_data)
+{
+ if ((trigger_data->mode & MODE_LINK) != 0 && trigger_data->link_up)
+ led_set_brightness(trigger_data->led_cdev, LED_FULL);
+ else
+ 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);
+ else
+ del_timer(&trigger_data->timer);
+}
+
+static ssize_t led_device_name_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_netdev_data *trigger_data = led_cdev->trigger_data;
+
+ read_lock(&trigger_data->lock);
+ sprintf(buf, "%s\n", trigger_data->device_name);
+ read_unlock(&trigger_data->lock);
+
+ return strlen(buf) + 1;
+}
+
+static ssize_t led_device_name_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_netdev_data *trigger_data = led_cdev->trigger_data;
+
+ if (size < 0 || size >= IFNAMSIZ)
+ return -EINVAL;
+
+ write_lock(&trigger_data->lock);
+
+ strcpy(trigger_data->device_name, buf);
+ if (size > 0 && trigger_data->device_name[size-1] == '\n')
+ trigger_data->device_name[size-1] = 0;
+
+ if (trigger_data->device_name[0] != 0) {
+ /* check for existing device to update from */
+ struct net_device *dev =
+ dev_get_by_name(&init_net, trigger_data->device_name);
+ if (dev != NULL) {
+ unsigned int flags = dev_get_flags(dev);
+ trigger_data->net_dev = dev;
+ trigger_data->link_up = (flags & IFF_LOWER_UP) != 0;
+ }
+ /* updates LEDs, may start timers */
+ set_baseline_state(trigger_data);
+ }
+
+ write_unlock(&trigger_data->lock);
+ return size;
+}
+
+static DEVICE_ATTR(device_name, 0644,
+ led_device_name_show, led_device_name_store);
+
+static const char enabled[] = "enabled";
+static const char disabled[] = "disabled";
+
+static ssize_t led_show_mode(struct device *dev,
+ struct device_attribute *attr, char *buf,
+ unsigned mode_bit)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_netdev_data *trigger_data = led_cdev->trigger_data;
+
+ return sprintf(buf, "%s\n", (trigger_data->mode & mode_bit) ?
+ enabled : disabled);
+}
+
+static void led_mode_set(struct led_netdev_data *data, unsigned bit)
+{
+ write_lock(&data->lock);
+ data->mode |= bit;
+ set_baseline_state(data);
+ write_unlock(&data->lock);
+}
+
+static void led_mode_clear(struct led_netdev_data *data, unsigned bit)
+{
+ write_lock(&data->lock);
+ data->mode &= ~bit;
+ set_baseline_state(data);
+ write_unlock(&data->lock);
+}
+
+static ssize_t led_store_mode(struct device *dev,
+ struct device_attribute *attr, const char *buf,
+ size_t size, unsigned mode_bit)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_netdev_data *trigger_data = led_cdev->trigger_data;
+ char *cp;
+ int len = size;
+
+ cp = memchr(buf, '\n', size);
+ if (cp)
+ len = cp - buf;
+ if (len == sizeof(enabled) - 1 && strncmp(buf, enabled, len) == 0)
+ led_mode_set(trigger_data, mode_bit);
+ else if (len == sizeof(disabled) - 1 &&
+ strncmp(buf, disabled, len) == 0)
+ led_mode_clear(trigger_data, mode_bit);
+ else
+ return -EINVAL;
+ return size;
+}
+
+#define LED_NETDEV_ATTR(name, mode_bit) \
+static ssize_t led_show_##name(struct device *dev, \
+ struct device_attribute *attr, \
+ char *buf) \
+{ \
+ return led_show_mode(dev, attr, buf, mode_bit); \
+} \
+ \
+static ssize_t led_store_##name(struct device *dev, \
+ struct device_attribute *attr, \
+ const char *buf, size_t size) \
+{ \
+ return led_store_mode(dev, attr, buf, size, mode_bit); \
+} \
+ \
+static DEVICE_ATTR(name, 0644, led_show_##name, led_store_##name)
+
+LED_NETDEV_ATTR(link, MODE_LINK);
+LED_NETDEV_ATTR(transmit, MODE_TX);
+LED_NETDEV_ATTR(receive, MODE_RX);
+
+static ssize_t led_interval_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_netdev_data *trigger_data = led_cdev->trigger_data;
+
+ read_lock(&trigger_data->lock);
+ sprintf(buf, "%u\n", jiffies_to_msecs(trigger_data->interval));
+ read_unlock(&trigger_data->lock);
+
+ return strlen(buf) + 1;
+}
+
+static ssize_t led_interval_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_netdev_data *trigger_data = led_cdev->trigger_data;
+ unsigned long value;
+ int ret;
+
+ ret = strict_strtoul(buf, 10, &value);
+ if (ret < 0)
+ return ret;
+
+ /* impose some basic bounds on the timer interval */
+ if (value >= 5 && value <= 10000) {
+ write_lock(&trigger_data->lock);
+ trigger_data->interval = msecs_to_jiffies(value);
+ set_baseline_state(trigger_data); /* resets timer */
+ write_unlock(&trigger_data->lock);
+ return size;
+ } else {
+ return -EINVAL;
+ }
+}
+
+static DEVICE_ATTR(interval, 0644, led_interval_show, led_interval_store);
+
+static int netdev_trig_notify(struct notifier_block *nb,
+ unsigned long evt,
+ void *dv)
+{
+ struct net_device *dev = dv;
+ struct led_netdev_data *trigger_data =
+ container_of(nb, struct led_netdev_data, notifier);
+
+ if (evt != NETDEV_UP && evt != NETDEV_DOWN && evt != NETDEV_CHANGE &&
+ evt != NETDEV_REGISTER && evt != NETDEV_UNREGISTER)
+ return NOTIFY_DONE;
+
+ write_lock(&trigger_data->lock);
+
+ if (strcmp(dev->name, trigger_data->device_name))
+ goto done;
+
+ if (evt == NETDEV_REGISTER) {
+ if (trigger_data->net_dev != NULL)
+ dev_put(trigger_data->net_dev);
+ dev_hold(dev);
+ trigger_data->net_dev = dev;
+ trigger_data->link_up = 0;
+ goto done;
+ }
+
+ if (evt == NETDEV_UNREGISTER && trigger_data->net_dev != NULL) {
+ dev_put(trigger_data->net_dev);
+ trigger_data->net_dev = NULL;
+ goto done;
+ }
+
+ /* UP / DOWN / CHANGE */
+
+ trigger_data->link_up = (evt != NETDEV_DOWN && netif_carrier_ok(dev));
+ set_baseline_state(trigger_data);
+
+done:
+ write_unlock(&trigger_data->lock);
+ return NOTIFY_DONE;
+}
+
+/* here's the real work! */
+static void netdev_trig_timer(unsigned long arg)
+{
+ struct led_netdev_data *trigger_data = (struct led_netdev_data *)arg;
+ struct rtnl_link_stats64 temp;
+ const struct rtnl_link_stats64 *dev_stats;
+ unsigned new_activity;
+
+ write_lock(&trigger_data->lock);
+
+ if (!trigger_data->link_up || !trigger_data->net_dev ||
+ (trigger_data->mode & (MODE_TX | MODE_RX)) == 0) {
+ /* we don't need to do timer work, just reflect link state. */
+ int on = (trigger_data->mode & MODE_LINK) != 0 &&
+ trigger_data->link_up;
+ led_set_brightness(trigger_data->led_cdev,
+ on ? LED_FULL : LED_OFF);
+ goto no_restart;
+ }
+
+ dev_stats = dev_get_stats(trigger_data->net_dev, &temp);
+
+ new_activity =
+ ((trigger_data->mode & MODE_TX) ? dev_stats->tx_packets : 0) +
+ ((trigger_data->mode & MODE_RX) ? dev_stats->rx_packets : 0);
+
+ if (trigger_data->mode & MODE_LINK) {
+ /* base state is ON (link present) */
+ /* if there's no link, we don't get this far
+ and the LED is off */
+
+ /* OFF -> ON always */
+ /* ON -> OFF on activity */
+ if (trigger_data->led_cdev->brightness == LED_OFF)
+ led_set_brightness(trigger_data->led_cdev, LED_FULL);
+ else if (trigger_data->last_activity != new_activity)
+ led_set_brightness(trigger_data->led_cdev, LED_OFF);
+ } else {
+ /* base state is OFF */
+ /* ON -> OFF always */
+ /* OFF -> ON on activity */
+ if (trigger_data->led_cdev->brightness == LED_FULL)
+ led_set_brightness(trigger_data->led_cdev, LED_OFF);
+ else if (trigger_data->last_activity != new_activity)
+ led_set_brightness(trigger_data->led_cdev, LED_FULL);
+ }
+
+ trigger_data->last_activity = new_activity;
+ mod_timer(&trigger_data->timer, jiffies + trigger_data->interval);
+
+no_restart:
+ write_unlock(&trigger_data->lock);
+}
+
+static void netdev_trig_activate(struct led_classdev *led_cdev)
+{
+ struct led_netdev_data *trigger_data;
+ int rc;
+
+ trigger_data = kzalloc(sizeof(struct led_netdev_data), GFP_KERNEL);
+ if (!trigger_data)
+ return;
+
+ rwlock_init(&trigger_data->lock);
+
+ 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);
+
+ trigger_data->led_cdev = led_cdev;
+ trigger_data->net_dev = NULL;
+ trigger_data->device_name[0] = 0;
+
+ trigger_data->mode = 0;
+ trigger_data->interval = msecs_to_jiffies(50);
+ trigger_data->link_up = 0;
+ trigger_data->last_activity = 0;
+
+ led_cdev->trigger_data = trigger_data;
+
+ rc = device_create_file(led_cdev->dev, &dev_attr_device_name);
+ if (rc)
+ goto err_out;
+ rc = device_create_file(led_cdev->dev, &dev_attr_link);
+ if (rc)
+ goto err_out_device_name;
+ rc = device_create_file(led_cdev->dev, &dev_attr_transmit);
+ if (rc)
+ goto err_out_link;
+ rc = device_create_file(led_cdev->dev, &dev_attr_receive);
+ if (rc)
+ goto err_out_transmit;
+ rc = device_create_file(led_cdev->dev, &dev_attr_interval);
+ if (rc)
+ goto err_out_receive;
+
+ register_netdevice_notifier(&trigger_data->notifier);
+ return;
+
+err_out_receive:
+ device_remove_file(led_cdev->dev, &dev_attr_receive);
+err_out_transmit:
+ device_remove_file(led_cdev->dev, &dev_attr_transmit);
+err_out_link:
+ device_remove_file(led_cdev->dev, &dev_attr_link);
+err_out_device_name:
+ device_remove_file(led_cdev->dev, &dev_attr_device_name);
+err_out:
+ led_cdev->trigger_data = NULL;
+ kfree(trigger_data);
+}
+
+static void netdev_trig_deactivate(struct led_classdev *led_cdev)
+{
+ struct led_netdev_data *trigger_data = led_cdev->trigger_data;
+
+ if (trigger_data) {
+ unregister_netdevice_notifier(&trigger_data->notifier);
+
+ device_remove_file(led_cdev->dev, &dev_attr_device_name);
+ device_remove_file(led_cdev->dev, &dev_attr_link);
+ device_remove_file(led_cdev->dev, &dev_attr_transmit);
+ device_remove_file(led_cdev->dev, &dev_attr_receive);
+ device_remove_file(led_cdev->dev, &dev_attr_interval);
+
+ write_lock(&trigger_data->lock);
+
+ if (trigger_data->net_dev) {
+ dev_put(trigger_data->net_dev);
+ trigger_data->net_dev = NULL;
+ }
+
+ write_unlock(&trigger_data->lock);
+
+ del_timer_sync(&trigger_data->timer);
+
+ kfree(trigger_data);
+ }
+}
+
+static struct led_trigger netdev_led_trigger = {
+ .name = "netdev",
+ .activate = netdev_trig_activate,
+ .deactivate = netdev_trig_deactivate,
+};
+
+static int __init netdev_trig_init(void)
+{
+ return led_trigger_register(&netdev_led_trigger);
+}
+
+static void __exit netdev_trig_exit(void)
+{
+ led_trigger_unregister(&netdev_led_trigger);
+}
+
+module_init(netdev_trig_init);
+module_exit(netdev_trig_exit);
+
+MODULE_AUTHOR("Oliver Jowett <[email protected]>");
+MODULE_DESCRIPTION("Netdev LED trigger");
+MODULE_LICENSE("GPL");
--
1.7.2.3


2010-11-29 10:15:55

by Andi Kleen

[permalink] [raw]
Subject: Re: [PATCH v2] add netdev led trigger

Eric Cooper <[email protected]> writes:

> Add a netdev LED trigger for all Blinkenlights lovers...
> Originally taken from https://dev.openwrt.org/ticket/2776
> Slightly updated for 2.6.24 by Mickey Lauer <[email protected]>
> and for 2.6.36 by Eric Cooper <[email protected]>

You should really send this to netdev too.

Some comments:

The timer seems power unfriendly -- it will always tick even if nothing
happens.

Using the device name as an identifier is not reliable, they may
not be unique.

rwlocks are deprecated.

your store code has a off by one I think, it's possible to put
not 0 terminated data in the string.


-Andi

--
[email protected] -- Speaking for myself only.

2010-11-30 23:40:45

by Lars-Peter Clausen

[permalink] [raw]
Subject: Re: [PATCH v2] add netdev led trigger

On 11/29/2010 03:34 AM, Eric Cooper wrote:
> Add a netdev LED trigger for all Blinkenlights lovers...
> Originally taken from https://dev.openwrt.org/ticket/2776
> Slightly updated for 2.6.24 by Mickey Lauer <[email protected]>
> and for 2.6.36 by Eric Cooper <[email protected]>
>
> Signed-off-by: Eric Cooper <[email protected]>
> ---
> Changes in v2:
> - Use individual entries for link, transmit, and receive;
> each can be "enabled" or "disabled"
> - Use strict_strtoul instead of simple_strtoul
> - Add descriptions to Documentation/ABI/testing/sysfs-class-led

Hi

Looks like most of the comments I had on v1 are still valid:
https://lkml.org/lkml/2010/11/15/506

- Lars

>
> Documentation/ABI/testing/sysfs-class-led | 64 ++++
> drivers/leds/Kconfig | 7 +
> drivers/leds/Makefile | 1 +
> drivers/leds/ledtrig-netdev.c | 475 +++++++++++++++++++++++++++++
> 4 files changed, 547 insertions(+), 0 deletions(-)
> create mode 100644 drivers/leds/ledtrig-netdev.c
>
> diff --git a/Documentation/ABI/testing/sysfs-class-led b/Documentation/ABI/testing/sysfs-class-led
> index 9e4541d..0b03863 100644
> --- a/Documentation/ABI/testing/sysfs-class-led
> +++ b/Documentation/ABI/testing/sysfs-class-led
> @@ -26,3 +26,67 @@ Description:
> scheduler is chosen. Trigger specific parameters can appear in
> /sys/class/leds/<led> once a given trigger is selected.
>
> +What: /sys/class/leds/<led>/device_name
> +Date: November 2010
> +KernelVersion: 2.6.37
> +Contact: Eric Cooper <[email protected]>
> +Description:
> + Network device name to monitor when trigger is set to "netdev".
> +
> +What: /sys/class/leds/<led>/interval
> +Date: November 2010
> +KernelVersion: 2.6.37
> +Contact: Eric Cooper <[email protected]>
> +Description:
> + Duration of LED blink in milliseconds when trigger is set to
> + "netdev".
> +
> +What: /sys/class/leds/<led>/link
> +Date: November 2010
> +KernelVersion: 2.6.37
> +Contact: Eric Cooper <[email protected]>
> +Description:
> + When trigger is set to "netdev", this value is either "enabled"
> + or "disabled". If enabled, this LED's normal state reflects
> + whether or not the link for the corresponding network device
> + is up (has carrier).
> +
> +What: /sys/class/leds/<led>/transmit
> +Date: November 2010
> +KernelVersion: 2.6.37
> +Contact: Eric Cooper <[email protected]>
> +Description:
> + When trigger is set to "netdev", this value is either "enabled"
> + or "disabled". If enabled, this LED blinks when data is
> + transmitted on the corresponding network device.
> +
> +What: /sys/class/leds/<led>/receive
> +Date: November 2010
> +KernelVersion: 2.6.37
> +Contact: Eric Cooper <[email protected]>
> +Description:
> + When trigger is set to "netdev", this value is either "enabled"
> + or "disabled". If enabled, this LED blinks when data is
> + received on the corresponding network device.
> +
> + Example configurations:
> +
> + Simple link status LED:
> + # echo netdev >someled/trigger
> + # echo eth0 >someled/device_name
> + # echo enabled >someled/link
> +
> + Ethernet-style link/activity LED:
> + # echo netdev >someled/trigger
> + # echo eth0 >someled/device_name
> + # echo enabled >someled/link
> + # echo enabled >someled/transmit
> + # echo enabled >someled/receive
> +
> + Modem-style tx/rx LEDs:
> + # echo netdev >led1/trigger
> + # echo ppp0 >led1/device_name
> + # echo enabled >led1/transmit
> + # echo netdev >led2/trigger
> + # echo ppp0 >led2/device_name
> + # echo enabled >led2/receive
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index 77b8fd2..8d81cd0 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -374,6 +374,13 @@ config LEDS_TRIGGER_HEARTBEAT
> load average.
> If unsure, say Y.
>
> +config LEDS_TRIGGER_NETDEV
> + tristate "LED Network Device Trigger"
> + depends on NET
> + help
> + This allows LEDs to be controlled by network device activity.
> + If unsure, say Y.
> +
> config LEDS_TRIGGER_BACKLIGHT
> tristate "LED backlight Trigger"
> help
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index aae6989..a3bb67d 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -49,6 +49,7 @@ obj-$(CONFIG_LEDS_DAC124S085) += leds-dac124s085.o
> obj-$(CONFIG_LEDS_TRIGGER_TIMER) += ledtrig-timer.o
> obj-$(CONFIG_LEDS_TRIGGER_IDE_DISK) += ledtrig-ide-disk.o
> obj-$(CONFIG_LEDS_TRIGGER_HEARTBEAT) += ledtrig-heartbeat.o
> +obj-$(CONFIG_LEDS_TRIGGER_NETDEV) += ledtrig-netdev.o
> obj-$(CONFIG_LEDS_TRIGGER_BACKLIGHT) += ledtrig-backlight.o
> obj-$(CONFIG_LEDS_TRIGGER_GPIO) += ledtrig-gpio.o
> obj-$(CONFIG_LEDS_TRIGGER_DEFAULT_ON) += ledtrig-default-on.o
> diff --git a/drivers/leds/ledtrig-netdev.c b/drivers/leds/ledtrig-netdev.c
> new file mode 100644
> index 0000000..eeb5ac8
> --- /dev/null
> +++ b/drivers/leds/ledtrig-netdev.c
> @@ -0,0 +1,475 @@
> +/*
> + * LED Kernel Netdev Trigger
> + *
> + * Toggles the LED to reflect the link and traffic state of a named net device
> + *
> + * Copyright 2007 Oliver Jowett <[email protected]>
> + *
> + * Derived from ledtrig-timer.c which is:
> + * Copyright 2005-2006 Openedhand Ltd.
> + * Author: Richard Purdie <[email protected]>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + */
> +
> +#include <linux/module.h>
> +#include <linux/jiffies.h>
> +#include <linux/kernel.h>
> +#include <linux/init.h>
> +#include <linux/list.h>
> +#include <linux/spinlock.h>
> +#include <linux/device.h>
> +#include <linux/sysdev.h>
> +#include <linux/netdevice.h>
> +#include <linux/timer.h>
> +#include <linux/ctype.h>
> +#include <linux/leds.h>
> +#include <linux/version.h>
> +#include <net/net_namespace.h>
> +
> +#include "leds.h"
> +
> +/*
> + * Configurable sysfs attributes:
> + *
> + * device_name - network device name to monitor
> + *
> + * interval - duration of LED blink, in milliseconds
> + *
> + * Each of the following attributes may be "enabled" or "disabled":
> + *
> + * link - if enabled, the LED's normal state reflects
> + * whether the link is up (has carrier)
> + * transmit - if enabled, the LED blinks on transmitted data
> + * receive - if enabled, the LED blinks on received data
> + *
> + * Some suggestions:
> + *
> + * Simple link status LED:
> + * $ echo netdev >someled/trigger
> + * $ echo eth0 >someled/device_name
> + * $ echo enabled >someled/link
> + *
> + * Ethernet-style link/activity LED:
> + * $ echo netdev >someled/trigger
> + * $ echo eth0 >someled/device_name
> + * $ echo enabled >someled/link
> + * $ echo enabled >someled/transmit
> + * $ echo enabled >someled/receive
> + *
> + * Modem-style tx/rx LEDs:
> + * $ echo netdev >led1/trigger
> + * $ echo ppp0 >led1/device_name
> + * $ echo enabled >led1/transmit
> + * $ echo netdev >led2/trigger
> + * $ echo ppp0 >led2/device_name
> + * $ echo enabled >led2/receive
> + */
> +
> +#define MODE_LINK 1
> +#define MODE_TX 2
> +#define MODE_RX 4
> +
> +struct led_netdev_data {
> + rwlock_t lock;
> +
> + struct timer_list timer;
> + struct notifier_block notifier;
> +
> + struct led_classdev *led_cdev;
> + struct net_device *net_dev;
> +
> + char device_name[IFNAMSIZ];
> + unsigned interval;
> + unsigned mode;
> + unsigned link_up;
> + unsigned last_activity;
> +};
> +
> +static void set_baseline_state(struct led_netdev_data *trigger_data)
> +{
> + if ((trigger_data->mode & MODE_LINK) != 0 && trigger_data->link_up)
> + led_set_brightness(trigger_data->led_cdev, LED_FULL);
> + else
> + 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);
> + else
> + del_timer(&trigger_data->timer);
> +}
> +
> +static ssize_t led_device_name_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_netdev_data *trigger_data = led_cdev->trigger_data;
> +
> + read_lock(&trigger_data->lock);
> + sprintf(buf, "%s\n", trigger_data->device_name);
> + read_unlock(&trigger_data->lock);
> +
> + return strlen(buf) + 1;
> +}
> +
> +static ssize_t led_device_name_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t size)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_netdev_data *trigger_data = led_cdev->trigger_data;
> +
> + if (size < 0 || size >= IFNAMSIZ)
> + return -EINVAL;
> +
> + write_lock(&trigger_data->lock);
> +
> + strcpy(trigger_data->device_name, buf);
> + if (size > 0 && trigger_data->device_name[size-1] == '\n')
> + trigger_data->device_name[size-1] = 0;
> +
> + if (trigger_data->device_name[0] != 0) {
> + /* check for existing device to update from */
> + struct net_device *dev =
> + dev_get_by_name(&init_net, trigger_data->device_name);
> + if (dev != NULL) {
> + unsigned int flags = dev_get_flags(dev);
> + trigger_data->net_dev = dev;
> + trigger_data->link_up = (flags & IFF_LOWER_UP) != 0;
> + }
> + /* updates LEDs, may start timers */
> + set_baseline_state(trigger_data);
> + }
> +
> + write_unlock(&trigger_data->lock);
> + return size;
> +}
> +
> +static DEVICE_ATTR(device_name, 0644,
> + led_device_name_show, led_device_name_store);
> +
> +static const char enabled[] = "enabled";
> +static const char disabled[] = "disabled";
> +
> +static ssize_t led_show_mode(struct device *dev,
> + struct device_attribute *attr, char *buf,
> + unsigned mode_bit)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_netdev_data *trigger_data = led_cdev->trigger_data;
> +
> + return sprintf(buf, "%s\n", (trigger_data->mode & mode_bit) ?
> + enabled : disabled);
> +}
> +
> +static void led_mode_set(struct led_netdev_data *data, unsigned bit)
> +{
> + write_lock(&data->lock);
> + data->mode |= bit;
> + set_baseline_state(data);
> + write_unlock(&data->lock);
> +}
> +
> +static void led_mode_clear(struct led_netdev_data *data, unsigned bit)
> +{
> + write_lock(&data->lock);
> + data->mode &= ~bit;
> + set_baseline_state(data);
> + write_unlock(&data->lock);
> +}
> +
> +static ssize_t led_store_mode(struct device *dev,
> + struct device_attribute *attr, const char *buf,
> + size_t size, unsigned mode_bit)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_netdev_data *trigger_data = led_cdev->trigger_data;
> + char *cp;
> + int len = size;
> +
> + cp = memchr(buf, '\n', size);
> + if (cp)
> + len = cp - buf;
> + if (len == sizeof(enabled) - 1 && strncmp(buf, enabled, len) == 0)
> + led_mode_set(trigger_data, mode_bit);
> + else if (len == sizeof(disabled) - 1 &&
> + strncmp(buf, disabled, len) == 0)
> + led_mode_clear(trigger_data, mode_bit);
> + else
> + return -EINVAL;
> + return size;
> +}
> +
> +#define LED_NETDEV_ATTR(name, mode_bit) \
> +static ssize_t led_show_##name(struct device *dev, \
> + struct device_attribute *attr, \
> + char *buf) \
> +{ \
> + return led_show_mode(dev, attr, buf, mode_bit); \
> +} \
> + \
> +static ssize_t led_store_##name(struct device *dev, \
> + struct device_attribute *attr, \
> + const char *buf, size_t size) \
> +{ \
> + return led_store_mode(dev, attr, buf, size, mode_bit); \
> +} \
> + \
> +static DEVICE_ATTR(name, 0644, led_show_##name, led_store_##name)
> +
> +LED_NETDEV_ATTR(link, MODE_LINK);
> +LED_NETDEV_ATTR(transmit, MODE_TX);
> +LED_NETDEV_ATTR(receive, MODE_RX);
> +
> +static ssize_t led_interval_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_netdev_data *trigger_data = led_cdev->trigger_data;
> +
> + read_lock(&trigger_data->lock);
> + sprintf(buf, "%u\n", jiffies_to_msecs(trigger_data->interval));
> + read_unlock(&trigger_data->lock);
> +
> + return strlen(buf) + 1;
> +}
> +
> +static ssize_t led_interval_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t size)
> +{
> + struct led_classdev *led_cdev = dev_get_drvdata(dev);
> + struct led_netdev_data *trigger_data = led_cdev->trigger_data;
> + unsigned long value;
> + int ret;
> +
> + ret = strict_strtoul(buf, 10, &value);
> + if (ret < 0)
> + return ret;
> +
> + /* impose some basic bounds on the timer interval */
> + if (value >= 5 && value <= 10000) {
> + write_lock(&trigger_data->lock);
> + trigger_data->interval = msecs_to_jiffies(value);
> + set_baseline_state(trigger_data); /* resets timer */
> + write_unlock(&trigger_data->lock);
> + return size;
> + } else {
> + return -EINVAL;
> + }
> +}
> +
> +static DEVICE_ATTR(interval, 0644, led_interval_show, led_interval_store);
> +
> +static int netdev_trig_notify(struct notifier_block *nb,
> + unsigned long evt,
> + void *dv)
> +{
> + struct net_device *dev = dv;
> + struct led_netdev_data *trigger_data =
> + container_of(nb, struct led_netdev_data, notifier);
> +
> + if (evt != NETDEV_UP && evt != NETDEV_DOWN && evt != NETDEV_CHANGE &&
> + evt != NETDEV_REGISTER && evt != NETDEV_UNREGISTER)
> + return NOTIFY_DONE;
> +
> + write_lock(&trigger_data->lock);
> +
> + if (strcmp(dev->name, trigger_data->device_name))
> + goto done;
> +
> + if (evt == NETDEV_REGISTER) {
> + if (trigger_data->net_dev != NULL)
> + dev_put(trigger_data->net_dev);
> + dev_hold(dev);
> + trigger_data->net_dev = dev;
> + trigger_data->link_up = 0;
> + goto done;
> + }
> +
> + if (evt == NETDEV_UNREGISTER && trigger_data->net_dev != NULL) {
> + dev_put(trigger_data->net_dev);
> + trigger_data->net_dev = NULL;
> + goto done;
> + }
> +
> + /* UP / DOWN / CHANGE */
> +
> + trigger_data->link_up = (evt != NETDEV_DOWN && netif_carrier_ok(dev));
> + set_baseline_state(trigger_data);
> +
> +done:
> + write_unlock(&trigger_data->lock);
> + return NOTIFY_DONE;
> +}
> +
> +/* here's the real work! */
> +static void netdev_trig_timer(unsigned long arg)
> +{
> + struct led_netdev_data *trigger_data = (struct led_netdev_data *)arg;
> + struct rtnl_link_stats64 temp;
> + const struct rtnl_link_stats64 *dev_stats;
> + unsigned new_activity;
> +
> + write_lock(&trigger_data->lock);
> +
> + if (!trigger_data->link_up || !trigger_data->net_dev ||
> + (trigger_data->mode & (MODE_TX | MODE_RX)) == 0) {
> + /* we don't need to do timer work, just reflect link state. */
> + int on = (trigger_data->mode & MODE_LINK) != 0 &&
> + trigger_data->link_up;
> + led_set_brightness(trigger_data->led_cdev,
> + on ? LED_FULL : LED_OFF);
> + goto no_restart;
> + }
> +
> + dev_stats = dev_get_stats(trigger_data->net_dev, &temp);
> +
> + new_activity =
> + ((trigger_data->mode & MODE_TX) ? dev_stats->tx_packets : 0) +
> + ((trigger_data->mode & MODE_RX) ? dev_stats->rx_packets : 0);
> +
> + if (trigger_data->mode & MODE_LINK) {
> + /* base state is ON (link present) */
> + /* if there's no link, we don't get this far
> + and the LED is off */
> +
> + /* OFF -> ON always */
> + /* ON -> OFF on activity */
> + if (trigger_data->led_cdev->brightness == LED_OFF)
> + led_set_brightness(trigger_data->led_cdev, LED_FULL);
> + else if (trigger_data->last_activity != new_activity)
> + led_set_brightness(trigger_data->led_cdev, LED_OFF);
> + } else {
> + /* base state is OFF */
> + /* ON -> OFF always */
> + /* OFF -> ON on activity */
> + if (trigger_data->led_cdev->brightness == LED_FULL)
> + led_set_brightness(trigger_data->led_cdev, LED_OFF);
> + else if (trigger_data->last_activity != new_activity)
> + led_set_brightness(trigger_data->led_cdev, LED_FULL);
> + }
> +
> + trigger_data->last_activity = new_activity;
> + mod_timer(&trigger_data->timer, jiffies + trigger_data->interval);
> +
> +no_restart:
> + write_unlock(&trigger_data->lock);
> +}
> +
> +static void netdev_trig_activate(struct led_classdev *led_cdev)
> +{
> + struct led_netdev_data *trigger_data;
> + int rc;
> +
> + trigger_data = kzalloc(sizeof(struct led_netdev_data), GFP_KERNEL);
> + if (!trigger_data)
> + return;
> +
> + rwlock_init(&trigger_data->lock);
> +
> + 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);
> +
> + trigger_data->led_cdev = led_cdev;
> + trigger_data->net_dev = NULL;
> + trigger_data->device_name[0] = 0;
> +
> + trigger_data->mode = 0;
> + trigger_data->interval = msecs_to_jiffies(50);
> + trigger_data->link_up = 0;
> + trigger_data->last_activity = 0;
> +
> + led_cdev->trigger_data = trigger_data;
> +
> + rc = device_create_file(led_cdev->dev, &dev_attr_device_name);
> + if (rc)
> + goto err_out;
> + rc = device_create_file(led_cdev->dev, &dev_attr_link);
> + if (rc)
> + goto err_out_device_name;
> + rc = device_create_file(led_cdev->dev, &dev_attr_transmit);
> + if (rc)
> + goto err_out_link;
> + rc = device_create_file(led_cdev->dev, &dev_attr_receive);
> + if (rc)
> + goto err_out_transmit;
> + rc = device_create_file(led_cdev->dev, &dev_attr_interval);
> + if (rc)
> + goto err_out_receive;
> +
> + register_netdevice_notifier(&trigger_data->notifier);
> + return;
> +
> +err_out_receive:
> + device_remove_file(led_cdev->dev, &dev_attr_receive);
> +err_out_transmit:
> + device_remove_file(led_cdev->dev, &dev_attr_transmit);
> +err_out_link:
> + device_remove_file(led_cdev->dev, &dev_attr_link);
> +err_out_device_name:
> + device_remove_file(led_cdev->dev, &dev_attr_device_name);
> +err_out:
> + led_cdev->trigger_data = NULL;
> + kfree(trigger_data);
> +}
> +
> +static void netdev_trig_deactivate(struct led_classdev *led_cdev)
> +{
> + struct led_netdev_data *trigger_data = led_cdev->trigger_data;
> +
> + if (trigger_data) {
> + unregister_netdevice_notifier(&trigger_data->notifier);
> +
> + device_remove_file(led_cdev->dev, &dev_attr_device_name);
> + device_remove_file(led_cdev->dev, &dev_attr_link);
> + device_remove_file(led_cdev->dev, &dev_attr_transmit);
> + device_remove_file(led_cdev->dev, &dev_attr_receive);
> + device_remove_file(led_cdev->dev, &dev_attr_interval);
> +
> + write_lock(&trigger_data->lock);
> +
> + if (trigger_data->net_dev) {
> + dev_put(trigger_data->net_dev);
> + trigger_data->net_dev = NULL;
> + }
> +
> + write_unlock(&trigger_data->lock);
> +
> + del_timer_sync(&trigger_data->timer);
> +
> + kfree(trigger_data);
> + }
> +}
> +
> +static struct led_trigger netdev_led_trigger = {
> + .name = "netdev",
> + .activate = netdev_trig_activate,
> + .deactivate = netdev_trig_deactivate,
> +};
> +
> +static int __init netdev_trig_init(void)
> +{
> + return led_trigger_register(&netdev_led_trigger);
> +}
> +
> +static void __exit netdev_trig_exit(void)
> +{
> + led_trigger_unregister(&netdev_led_trigger);
> +}
> +
> +module_init(netdev_trig_init);
> +module_exit(netdev_trig_exit);
> +
> +MODULE_AUTHOR("Oliver Jowett <[email protected]>");
> +MODULE_DESCRIPTION("Netdev LED trigger");
> +MODULE_LICENSE("GPL");

2010-12-01 00:03:16

by Eric Cooper

[permalink] [raw]
Subject: Re: [PATCH v2] add netdev led trigger

On Mon, Nov 29, 2010 at 11:15:51AM +0100, Andi Kleen wrote:
> Using the device name as an identifier is not reliable, they may not
> be unique.

I'm confused about this -- how else can the user specify the desired network
interface?

> rwlocks are deprecated.

In favor of what? Should I use a spinlock?

Thanks for the feedback.

--
Eric Cooper e c c @ c m u . e d u

2010-12-01 14:03:37

by Andi Kleen

[permalink] [raw]
Subject: Re: [PATCH v2] add netdev led trigger

On Tue, Nov 30, 2010 at 07:03:00PM -0500, Eric Cooper wrote:
> On Mon, Nov 29, 2010 at 11:15:51AM +0100, Andi Kleen wrote:
> > Using the device name as an identifier is not reliable, they may not
> > be unique.
>
> I'm confused about this -- how else can the user specify the desired network
> interface?

For presenting the user the name is probably still the best, but internally
better use the interface index.
>
> > rwlocks are deprecated.
>
> In favor of what? Should I use a spinlock?

spinlocks or mutexes.

-Andi

--
[email protected] -- Speaking for myself only.