diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/acpi/thermal.c | 28 |
1 files changed, 18 insertions, 10 deletions
diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c index bc6d5866ef9..69ec73b0239 100644 --- a/drivers/acpi/thermal.c +++ b/drivers/acpi/thermal.c @@ -195,6 +195,7 @@ struct acpi_thermal { struct acpi_thermal_trips trips; struct acpi_handle_list devices; struct timer_list timer; + struct mutex lock; }; static const struct file_operations acpi_thermal_state_fops = { @@ -711,6 +712,7 @@ static void acpi_thermal_check(void *data) int result = 0; struct acpi_thermal *tz = data; unsigned long sleep_time = 0; + unsigned long timeout_jiffies = 0; int i = 0; struct acpi_thermal_state state; @@ -720,11 +722,15 @@ static void acpi_thermal_check(void *data) return; } + /* Check if someone else is already running */ + if (!mutex_trylock(&tz->lock)) + return; + state = tz->state; result = acpi_thermal_get_temperature(tz); if (result) - return; + goto unlock; memset(&tz->state, 0, sizeof(tz->state)); @@ -787,10 +793,13 @@ static void acpi_thermal_check(void *data) * a thermal event occurs). Note that _TSP and _TZD values are * given in 1/10th seconds (we must covert to milliseconds). */ - if (tz->state.passive) + if (tz->state.passive) { sleep_time = tz->trips.passive.tsp * 100; - else if (tz->polling_frequency > 0) + timeout_jiffies = jiffies + (HZ * sleep_time) / 1000; + } else if (tz->polling_frequency > 0) { sleep_time = tz->polling_frequency * 100; + timeout_jiffies = round_jiffies(jiffies + (HZ * sleep_time) / 1000); + } ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s: temperature[%lu] sleep[%lu]\n", tz->name, tz->temperature, sleep_time)); @@ -804,17 +813,16 @@ static void acpi_thermal_check(void *data) del_timer(&(tz->timer)); } else { if (timer_pending(&(tz->timer))) - mod_timer(&(tz->timer), - jiffies + (HZ * sleep_time) / 1000); + mod_timer(&(tz->timer), timeout_jiffies); else { tz->timer.data = (unsigned long)tz; tz->timer.function = acpi_thermal_run; - tz->timer.expires = jiffies + (HZ * sleep_time) / 1000; + tz->timer.expires = timeout_jiffies; add_timer(&(tz->timer)); } } - - return; + unlock: + mutex_unlock(&tz->lock); } /* -------------------------------------------------------------------------- @@ -1251,7 +1259,7 @@ static int acpi_thermal_add(struct acpi_device *device) strcpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME); strcpy(acpi_device_class(device), ACPI_THERMAL_CLASS); acpi_driver_data(device) = tz; - + mutex_init(&tz->lock); result = acpi_thermal_get_info(tz); if (result) goto end; @@ -1321,7 +1329,7 @@ static int acpi_thermal_remove(struct acpi_device *device, int type) } acpi_thermal_remove_fs(device); - + mutex_destroy(&tz->lock); kfree(tz); return 0; } |