openwrtv3/target/linux/generic/files/drivers/net/phy/swconfig_leds.c
Kevin Darbyshire-Bryant 0b4e3b1bed generic: swconfig: reduce lock duration on sysfs files
sysfs attributes 'port_mask' & 'speed_mask' held locks whilst doing
mundane tasks such as sprintf.  Refactor code to reduce length of time
locks are held unnecessarily.

Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>
2018-02-14 07:54:24 +01:00

556 lines
13 KiB
C

/*
* swconfig_led.c: LED trigger support for the switch configuration API
*
* Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
*/
#ifdef CONFIG_SWCONFIG_LEDS
#include <linux/leds.h>
#include <linux/ctype.h>
#include <linux/device.h>
#include <linux/workqueue.h>
#define SWCONFIG_LED_TIMER_INTERVAL (HZ / 10)
#define SWCONFIG_LED_NUM_PORTS 32
#define SWCONFIG_LED_PORT_SPEED_NA 0x01 /* unknown speed */
#define SWCONFIG_LED_PORT_SPEED_10 0x02 /* 10 Mbps */
#define SWCONFIG_LED_PORT_SPEED_100 0x04 /* 100 Mbps */
#define SWCONFIG_LED_PORT_SPEED_1000 0x08 /* 1000 Mbps */
#define SWCONFIG_LED_PORT_SPEED_ALL (SWCONFIG_LED_PORT_SPEED_NA | \
SWCONFIG_LED_PORT_SPEED_10 | \
SWCONFIG_LED_PORT_SPEED_100 | \
SWCONFIG_LED_PORT_SPEED_1000)
#define SWCONFIG_LED_MODE_LINK 0x01
#define SWCONFIG_LED_MODE_TX 0x02
#define SWCONFIG_LED_MODE_RX 0x04
#define SWCONFIG_LED_MODE_TXRX (SWCONFIG_LED_MODE_TX | \
SWCONFIG_LED_MODE_RX)
#define SWCONFIG_LED_MODE_ALL (SWCONFIG_LED_MODE_LINK | \
SWCONFIG_LED_MODE_TX | \
SWCONFIG_LED_MODE_RX)
struct switch_led_trigger {
struct led_trigger trig;
struct switch_dev *swdev;
struct delayed_work sw_led_work;
u32 port_mask;
u32 port_link;
unsigned long long port_tx_traffic[SWCONFIG_LED_NUM_PORTS];
unsigned long long port_rx_traffic[SWCONFIG_LED_NUM_PORTS];
u8 link_speed[SWCONFIG_LED_NUM_PORTS];
};
struct swconfig_trig_data {
struct led_classdev *led_cdev;
struct switch_dev *swdev;
rwlock_t lock;
u32 port_mask;
bool prev_link;
unsigned long prev_traffic;
enum led_brightness prev_brightness;
u8 mode;
u8 speed_mask;
};
static void
swconfig_trig_set_brightness(struct swconfig_trig_data *trig_data,
enum led_brightness brightness)
{
led_set_brightness(trig_data->led_cdev, brightness);
trig_data->prev_brightness = brightness;
}
static void
swconfig_trig_update_port_mask(struct led_trigger *trigger)
{
struct list_head *entry;
struct switch_led_trigger *sw_trig;
u32 port_mask;
if (!trigger)
return;
sw_trig = (void *) trigger;
port_mask = 0;
read_lock(&trigger->leddev_list_lock);
list_for_each(entry, &trigger->led_cdevs) {
struct led_classdev *led_cdev;
struct swconfig_trig_data *trig_data;
led_cdev = list_entry(entry, struct led_classdev, trig_list);
trig_data = led_cdev->trigger_data;
if (trig_data) {
read_lock(&trig_data->lock);
port_mask |= trig_data->port_mask;
read_unlock(&trig_data->lock);
}
}
read_unlock(&trigger->leddev_list_lock);
sw_trig->port_mask = port_mask;
if (port_mask)
schedule_delayed_work(&sw_trig->sw_led_work,
SWCONFIG_LED_TIMER_INTERVAL);
else
cancel_delayed_work_sync(&sw_trig->sw_led_work);
}
static ssize_t
swconfig_trig_port_mask_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t size)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct swconfig_trig_data *trig_data = led_cdev->trigger_data;
unsigned long port_mask;
int ret;
bool changed;
ret = kstrtoul(buf, 0, &port_mask);
if (ret)
return ret;
write_lock(&trig_data->lock);
changed = (trig_data->port_mask != port_mask);
trig_data->port_mask = port_mask;
write_unlock(&trig_data->lock);
if (changed) {
if (port_mask == 0)
swconfig_trig_set_brightness(trig_data, LED_OFF);
swconfig_trig_update_port_mask(led_cdev->trigger);
}
return size;
}
static ssize_t
swconfig_trig_port_mask_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct swconfig_trig_data *trig_data = led_cdev->trigger_data;
u32 port_mask;
read_lock(&trig_data->lock);
port_mask = trig_data->port_mask;
read_unlock(&trig_data->lock);
sprintf(buf, "%#x\n", port_mask);
return strlen(buf) + 1;
}
static DEVICE_ATTR(port_mask, 0644, swconfig_trig_port_mask_show,
swconfig_trig_port_mask_store);
/* speed_mask file handler - display value */
static ssize_t swconfig_trig_speed_mask_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct swconfig_trig_data *trig_data = led_cdev->trigger_data;
u8 speed_mask;
read_lock(&trig_data->lock);
speed_mask = trig_data->speed_mask;
read_unlock(&trig_data->lock);
sprintf(buf, "%#x\n", speed_mask);
return strlen(buf) + 1;
}
/* speed_mask file handler - store value */
static ssize_t swconfig_trig_speed_mask_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t size)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct swconfig_trig_data *trig_data = led_cdev->trigger_data;
u8 speed_mask;
int ret;
ret = kstrtou8(buf, 0, &speed_mask);
if (ret)
return ret;
write_lock(&trig_data->lock);
trig_data->speed_mask = speed_mask & SWCONFIG_LED_PORT_SPEED_ALL;
write_unlock(&trig_data->lock);
return size;
}
/* speed_mask special file */
static DEVICE_ATTR(speed_mask, 0644, swconfig_trig_speed_mask_show,
swconfig_trig_speed_mask_store);
static ssize_t swconfig_trig_mode_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct swconfig_trig_data *trig_data = led_cdev->trigger_data;
u8 mode;
read_lock(&trig_data->lock);
mode = trig_data->mode;
read_unlock(&trig_data->lock);
if (mode == 0) {
strcpy(buf, "none\n");
} else {
if (mode & SWCONFIG_LED_MODE_LINK)
strcat(buf, "link ");
if (mode & SWCONFIG_LED_MODE_TX)
strcat(buf, "tx ");
if (mode & SWCONFIG_LED_MODE_RX)
strcat(buf, "rx ");
strcat(buf, "\n");
}
return strlen(buf)+1;
}
static ssize_t swconfig_trig_mode_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct swconfig_trig_data *trig_data = led_cdev->trigger_data;
char copybuf[128];
int new_mode = -1;
char *p, *token;
/* take a copy since we don't want to trash the inbound buffer when using strsep */
strncpy(copybuf, buf, sizeof(copybuf));
copybuf[sizeof(copybuf) - 1] = 0;
p = copybuf;
while ((token = strsep(&p, " \t\n")) != NULL) {
if (!*token)
continue;
if (new_mode < 0)
new_mode = 0;
if (!strcmp(token, "none"))
new_mode = 0;
else if (!strcmp(token, "tx"))
new_mode |= SWCONFIG_LED_MODE_TX;
else if (!strcmp(token, "rx"))
new_mode |= SWCONFIG_LED_MODE_RX;
else if (!strcmp(token, "link"))
new_mode |= SWCONFIG_LED_MODE_LINK;
else
return -EINVAL;
}
if (new_mode < 0)
return -EINVAL;
write_lock(&trig_data->lock);
trig_data->mode = (u8)new_mode;
write_unlock(&trig_data->lock);
return size;
}
/* mode special file */
static DEVICE_ATTR(mode, 0644, swconfig_trig_mode_show,
swconfig_trig_mode_store);
static void
swconfig_trig_activate(struct led_classdev *led_cdev)
{
struct switch_led_trigger *sw_trig;
struct swconfig_trig_data *trig_data;
int err;
if (led_cdev->trigger->activate != swconfig_trig_activate)
return;
trig_data = kzalloc(sizeof(struct swconfig_trig_data), GFP_KERNEL);
if (!trig_data)
return;
sw_trig = (void *) led_cdev->trigger;
rwlock_init(&trig_data->lock);
trig_data->led_cdev = led_cdev;
trig_data->swdev = sw_trig->swdev;
trig_data->speed_mask = SWCONFIG_LED_PORT_SPEED_ALL;
trig_data->mode = SWCONFIG_LED_MODE_ALL;
led_cdev->trigger_data = trig_data;
err = device_create_file(led_cdev->dev, &dev_attr_port_mask);
if (err)
goto err_free;
err = device_create_file(led_cdev->dev, &dev_attr_speed_mask);
if (err)
goto err_dev_free;
err = device_create_file(led_cdev->dev, &dev_attr_mode);
if (err)
goto err_mode_free;
return;
err_mode_free:
device_remove_file(led_cdev->dev, &dev_attr_speed_mask);
err_dev_free:
device_remove_file(led_cdev->dev, &dev_attr_port_mask);
err_free:
led_cdev->trigger_data = NULL;
kfree(trig_data);
}
static void
swconfig_trig_deactivate(struct led_classdev *led_cdev)
{
struct swconfig_trig_data *trig_data;
swconfig_trig_update_port_mask(led_cdev->trigger);
trig_data = (void *) led_cdev->trigger_data;
if (trig_data) {
device_remove_file(led_cdev->dev, &dev_attr_port_mask);
device_remove_file(led_cdev->dev, &dev_attr_speed_mask);
device_remove_file(led_cdev->dev, &dev_attr_mode);
kfree(trig_data);
}
}
/*
* link off -> led off (can't be any other reason to turn it on)
* link on:
* mode link: led on by default only if speed matches, else off
* mode txrx: blink only if speed matches, else off
*/
static void
swconfig_trig_led_event(struct switch_led_trigger *sw_trig,
struct led_classdev *led_cdev)
{
struct swconfig_trig_data *trig_data;
u32 port_mask;
bool link;
u8 speed_mask, mode;
enum led_brightness led_base, led_blink;
trig_data = led_cdev->trigger_data;
if (!trig_data)
return;
read_lock(&trig_data->lock);
port_mask = trig_data->port_mask;
speed_mask = trig_data->speed_mask;
mode = trig_data->mode;
read_unlock(&trig_data->lock);
link = !!(sw_trig->port_link & port_mask);
if (!link) {
if (trig_data->prev_brightness != LED_OFF)
swconfig_trig_set_brightness(trig_data, LED_OFF); /* and stop */
}
else {
unsigned long traffic;
int speedok; /* link speed flag */
int i;
led_base = LED_FULL;
led_blink = LED_OFF;
traffic = 0;
speedok = 0;
for (i = 0; i < SWCONFIG_LED_NUM_PORTS; i++) {
if (port_mask & (1 << i)) {
if (sw_trig->link_speed[i] & speed_mask) {
traffic += ((mode & SWCONFIG_LED_MODE_TX) ?
sw_trig->port_tx_traffic[i] : 0) +
((mode & SWCONFIG_LED_MODE_RX) ?
sw_trig->port_rx_traffic[i] : 0);
speedok = 1;
}
}
}
if (speedok) {
/* At least one port speed matches speed_mask */
if (!(mode & SWCONFIG_LED_MODE_LINK)) {
led_base = LED_OFF;
led_blink = LED_FULL;
}
if (trig_data->prev_brightness != led_base)
swconfig_trig_set_brightness(trig_data,
led_base);
else if (traffic != trig_data->prev_traffic)
swconfig_trig_set_brightness(trig_data,
led_blink);
} else if (trig_data->prev_brightness != LED_OFF)
swconfig_trig_set_brightness(trig_data, LED_OFF);
trig_data->prev_traffic = traffic;
}
trig_data->prev_link = link;
}
static void
swconfig_trig_update_leds(struct switch_led_trigger *sw_trig)
{
struct list_head *entry;
struct led_trigger *trigger;
trigger = &sw_trig->trig;
read_lock(&trigger->leddev_list_lock);
list_for_each(entry, &trigger->led_cdevs) {
struct led_classdev *led_cdev;
led_cdev = list_entry(entry, struct led_classdev, trig_list);
swconfig_trig_led_event(sw_trig, led_cdev);
}
read_unlock(&trigger->leddev_list_lock);
}
static void
swconfig_led_work_func(struct work_struct *work)
{
struct switch_led_trigger *sw_trig;
struct switch_dev *swdev;
u32 port_mask;
u32 link;
int i;
sw_trig = container_of(work, struct switch_led_trigger,
sw_led_work.work);
port_mask = sw_trig->port_mask;
swdev = sw_trig->swdev;
link = 0;
for (i = 0; i < SWCONFIG_LED_NUM_PORTS; i++) {
u32 port_bit;
sw_trig->link_speed[i] = 0;
port_bit = BIT(i);
if ((port_mask & port_bit) == 0)
continue;
if (swdev->ops->get_port_link) {
struct switch_port_link port_link;
memset(&port_link, '\0', sizeof(port_link));
swdev->ops->get_port_link(swdev, i, &port_link);
if (port_link.link) {
link |= port_bit;
switch (port_link.speed) {
case SWITCH_PORT_SPEED_UNKNOWN:
sw_trig->link_speed[i] =
SWCONFIG_LED_PORT_SPEED_NA;
break;
case SWITCH_PORT_SPEED_10:
sw_trig->link_speed[i] =
SWCONFIG_LED_PORT_SPEED_10;
break;
case SWITCH_PORT_SPEED_100:
sw_trig->link_speed[i] =
SWCONFIG_LED_PORT_SPEED_100;
break;
case SWITCH_PORT_SPEED_1000:
sw_trig->link_speed[i] =
SWCONFIG_LED_PORT_SPEED_1000;
break;
}
}
}
if (swdev->ops->get_port_stats) {
struct switch_port_stats port_stats;
memset(&port_stats, '\0', sizeof(port_stats));
swdev->ops->get_port_stats(swdev, i, &port_stats);
sw_trig->port_tx_traffic[i] = port_stats.tx_bytes;
sw_trig->port_rx_traffic[i] = port_stats.rx_bytes;
}
}
sw_trig->port_link = link;
swconfig_trig_update_leds(sw_trig);
schedule_delayed_work(&sw_trig->sw_led_work,
SWCONFIG_LED_TIMER_INTERVAL);
}
static int
swconfig_create_led_trigger(struct switch_dev *swdev)
{
struct switch_led_trigger *sw_trig;
int err;
if (!swdev->ops->get_port_link)
return 0;
sw_trig = kzalloc(sizeof(struct switch_led_trigger), GFP_KERNEL);
if (!sw_trig)
return -ENOMEM;
sw_trig->swdev = swdev;
sw_trig->trig.name = swdev->devname;
sw_trig->trig.activate = swconfig_trig_activate;
sw_trig->trig.deactivate = swconfig_trig_deactivate;
INIT_DELAYED_WORK(&sw_trig->sw_led_work, swconfig_led_work_func);
err = led_trigger_register(&sw_trig->trig);
if (err)
goto err_free;
swdev->led_trigger = sw_trig;
return 0;
err_free:
kfree(sw_trig);
return err;
}
static void
swconfig_destroy_led_trigger(struct switch_dev *swdev)
{
struct switch_led_trigger *sw_trig;
sw_trig = swdev->led_trigger;
if (sw_trig) {
cancel_delayed_work_sync(&sw_trig->sw_led_work);
led_trigger_unregister(&sw_trig->trig);
kfree(sw_trig);
}
}
#else /* SWCONFIG_LEDS */
static inline int
swconfig_create_led_trigger(struct switch_dev *swdev) { return 0; }
static inline void
swconfig_destroy_led_trigger(struct switch_dev *swdev) { }
#endif /* CONFIG_SWCONFIG_LEDS */