From 6e2157858ac94530fddbf19dc59ab6b392baf1f3 Mon Sep 17 00:00:00 2001 From: Alexey Starikovskiy Date: Sat, 1 Sep 2007 00:11:59 +0400 Subject: ACPI: Thermal: Drop concurrent thermal checks Fix for #3686, where get_temperature() may cause thermal notify, which causes one more get_temperature(). Signed-off-by: Alexey Starikovskiy Signed-off-by: Len Brown --- drivers/acpi/thermal.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) (limited to 'drivers/acpi/thermal.c') diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c index 15d5fdc..69ec73b 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 = { @@ -721,11 +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)); @@ -816,8 +821,8 @@ static void acpi_thermal_check(void *data) add_timer(&(tz->timer)); } } - - return; + unlock: + mutex_unlock(&tz->lock); } /* -------------------------------------------------------------------------- @@ -1254,7 +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; @@ -1324,7 +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; } -- cgit v1.1