[PATCH 1/1] thermal: core: call thermal_zone_device_update() after mode update

Eduardo Valentin
2016-06-22T05:09:27Z

Because several drivers do the following pattern:
.set_mode()
...
local_data->mode = new_mode;
thermal_zone_device_update(tz);

makes sense to simply do the thermal_zone_device_update()
in thermal core, after setting the new mode.

Also, this patch also remove deadlocks on drivers that
call thermal_zone_device_update() on .set_mode(),
as .set_mode() is now called always with tz->lock held.

Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: linux-acpi@vger.kernel.org
Cc: "Lee, Chun-Yi" <jlee@suse.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Keerthy <j-keerthy@ti.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-omap@vger.kernel.org
Cc: platform-driver-x86@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
---
Rui, Keerthy,

I think this patch should take care of the introduced deadlock.

Let me know if solves on your end.

BR,

Eduardo
---

drivers/acpi/thermal.c | 2 --
drivers/platform/x86/acerhdf.c | 1 -
drivers/thermal/imx_thermal.c | 1 -
drivers/thermal/of-thermal.c | 8 ++---
drivers/thermal/thermal_core.c | 41 +++++++++++++++++-----
drivers/thermal/thermal_sysfs.c | 1 +
drivers/thermal/ti-soc-thermal/ti-thermal-common.c | 1 -
7 files changed, 36 insertions(+), 19 deletions(-)

diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
index 82707f9..8582b88 100644
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -519,8 +519,6 @@ static void acpi_thermal_check(void *data)

if (!tz->tz_enabled)
return;
-
- thermal_zone_device_update(tz->thermal_zone);
}

/* sys I/F for generic thermal sysfs support */
diff --git a/drivers/platform/x86/acerhdf.c b/drivers/platform/x86/acerhdf.c
index 460fa67..aee33ba 100644
--- a/drivers/platform/x86/acerhdf.c
+++ b/drivers/platform/x86/acerhdf.c
@@ -405,7 +405,6 @@ static inline void acerhdf_enable_kernelmode(void)
kernelmode = 1;

thz_dev->polling_delay = interval*1000;
- thermal_zone_device_update(thz_dev);
pr_notice("kernel mode fan control ON\n");
}

diff --git a/drivers/thermal/imx_thermal.c b/drivers/thermal/imx_thermal.c
index c5547bd..a413eb6 100644
--- a/drivers/thermal/imx_thermal.c
+++ b/drivers/thermal/imx_thermal.c
@@ -246,7 +246,6 @@ static int imx_set_mode(struct thermal_zone_device *tz,
}

data->mode = mode;
- thermal_zone_device_update(tz);

return 0;
}
diff --git a/drivers/thermal/of-thermal.c b/drivers/thermal/of-thermal.c
index b8e509c..b44c102 100644
--- a/drivers/thermal/of-thermal.c
+++ b/drivers/thermal/of-thermal.c
@@ -181,9 +181,6 @@ static int of_thermal_set_emul_temp(struct thermal_zone_device *tz,
{
struct __thermal_zone *data = tz->devdata;

- if (!data->ops || !data->ops->set_emul_temp)
- return -EINVAL;
-
return data->ops->set_emul_temp(data->sensor_data, temp);
}

@@ -292,7 +289,6 @@ static int of_thermal_set_mode(struct thermal_zone_device *tz,
mutex_unlock(&tz->lock);

data->mode = mode;
- thermal_zone_device_update(tz);

return 0;
}
@@ -427,7 +423,9 @@ thermal_zone_of_add_sensor(struct device_node *zone,

tzd->ops->get_temp = of_thermal_get_temp;
tzd->ops->get_trend = of_thermal_get_trend;
- tzd->ops->set_emul_temp = of_thermal_set_emul_temp;
+ if (ops->set_emul_temp)
+ tzd->ops->set_emul_temp = of_thermal_set_emul_temp;
+
mutex_unlock(&tzd->lock);

return tzd;
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 09da955..bb1ede7 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -323,6 +323,21 @@ static void handle_non_critical_trips(struct thermal_zone_device *tz,
def_governor->throttle(tz, trip);
}

+static void thermal_zone_update_stats(struct thermal_zone_device *tz,
+ int last_trip, int cur_trip)
+{
+ unsigned long long cur_time = get_jiffies_64();
+ struct thermal_zone_stats *cur, *last;
+
+ cur = tz->stats_table[cur_trip];
+ last = tz->stats_table[last_trip];
+
+ cur->counter++;
+ cur->last_time = cur_time;
+
+ last->time_in += cur_time - last->last_time;
+}
+
static void thermal_tripped_notify(struct thermal_zone_device *tz,
int trip, enum thermal_trip_type trip_type,
int trip_temp)
@@ -333,6 +348,7 @@ static void thermal_tripped_notify(struct thermal_zone_device *tz,
NULL };
int upper_trip_hyst, upper_trip_temp, trip_hyst = 0;
int ret = 0;
+ int cur_trip, last_trip;

snprintf(tuv_name, sizeof(tuv_name), "THERMAL_ZONE=%s", tz->type);
snprintf(tuv_temp, sizeof(tuv_temp), "TEMP=%d", tz->temperature);
@@ -344,8 +360,11 @@ static void thermal_tripped_notify(struct thermal_zone_device *tz,
mutex_lock(&tz->lock);

/* crossing up */
- if (tz->last_temperature < trip_temp && trip_temp < tz->temperature)
+ if (tz->last_temperature < trip_temp && trip_temp < tz->temperature) {
kobject_uevent_env(&tz->device.kobj, KOBJ_CHANGE, msg);
+ last_trip = trip - 1;
+ cur_trip = trip;
+ }

if (tz->ops->get_trip_hyst)
tz->ops->get_trip_hyst(tz, trip, &trip_hyst);
@@ -355,6 +374,8 @@ static void thermal_tripped_notify(struct thermal_zone_device *tz,
if (tz->last_temperature > trip_temp && trip_temp > tz->temperature) {
snprintf(tuv_trip, sizeof(tuv_trip), "TRIP=%d", trip - 1);
kobject_uevent_env(&tz->device.kobj, KOBJ_CHANGE, msg);
+ last_trip = trip;
+ cur_trip = trip - 1;
}

ret = tz->ops->get_trip_temp(tz, trip + 1, &upper_trip_temp);
@@ -369,19 +390,15 @@ static void thermal_tripped_notify(struct thermal_zone_device *tz,
upper_trip_temp > tz->temperature)
kobject_uevent_env(&tz->device.kobj, KOBJ_CHANGE, msg);

+ thermal_zone_device_update_stats(tz, last_trip, cur_trip);
unlock:
mutex_unlock(&tz->lock);
}

static void handle_critical_trips(struct thermal_zone_device *tz,
- int trip, enum thermal_trip_type trip_type)
+ int trip, enum thermal_trip_type trip_type,
+ int trip_temp)
{
- int trip_temp;
-
- tz->ops->get_trip_temp(tz, trip, &trip_temp);
-
- thermal_tripped_notify(tz, trip, trip_type, trip_temp);
-
/* If we have not crossed the trip_temp, we do not care. */
if (trip_temp <= 0 || tz->temperature < trip_temp)
return;
@@ -402,15 +419,21 @@ static void handle_critical_trips(struct thermal_zone_device *tz,
static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
{
enum thermal_trip_type type;
+ int trip_temp;
+
+ tz->ops->get_trip_temp(tz, trip, &trip_temp);

/* Ignore disabled trip points */
if (test_bit(trip, &tz->trips_disabled))
return;

tz->ops->get_trip_type(tz, trip, &type);
+ tz->ops->get_trip_type(tz, trip, &trip_temp);
+
+ thermal_tripped_notify(tz, trip, trip_type, trip_temp);

if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
- handle_critical_trips(tz, trip, type);
+ handle_critical_trips(tz, trip, type, trip_temp);
else
handle_non_critical_trips(tz, trip, type);
}
diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c
index 743df50..3d0dc30 100644
--- a/drivers/thermal/thermal_sysfs.c
+++ b/drivers/thermal/thermal_sysfs.c
@@ -100,6 +100,7 @@ mode_store(struct device *dev, struct device_attribute *attr,
mutex_lock(&tz->lock);
result = tz->ops->set_mode(tz, mode);
mutex_unlock(&tz->lock);
+ thermal_zone_device_update(tz);

if (result)
return result;
diff --git a/drivers/thermal/ti-soc-thermal/ti-thermal-common.c b/drivers/thermal/ti-soc-thermal/ti-thermal-common.c
index 15c0a9a..9a5a3a3 100644
--- a/drivers/thermal/ti-soc-thermal/ti-thermal-common.c
+++ b/drivers/thermal/ti-soc-thermal/ti-thermal-common.c
@@ -205,7 +205,6 @@ static int ti_thermal_set_mode(struct thermal_zone_device *thermal,
data->mode = mode;
ti_bandgap_write_update_interval(bgp, data->sensor_id,
data->ti_thermal->polling_delay);
- thermal_zone_device_update(data->ti_thermal);
dev_dbg(&thermal->device, "thermal polling set for duration=%d msec\n",
data->ti_thermal->polling_delay);

--
2.1.4