Re: [PATCHv2 1/1] thermal: core: call thermal_zone_device_update() after mode update

From: Keerthy
Date: Wed Jun 22 2016 - 05:36:30 EST




On Wednesday 22 June 2016 10:45 AM, Eduardo Valentin wrote:
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.

http://pastebin.ubuntu.com/17687601/

linux-next + current v2 of the patch.
The back trace still comes.

Regards,
Keerthy


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@xxxxxxxxxxxxx>
Cc: Len Brown <lenb@xxxxxxxxxx>
Cc: linux-acpi@xxxxxxxxxxxxxxx
Cc: "Lee, Chun-Yi" <jlee@xxxxxxxx>
Cc: Darren Hart <dvhart@xxxxxxxxxxxxx>
Cc: Zhang Rui <rui.zhang@xxxxxxxxx>
Cc: Keerthy <j-keerthy@xxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-omap@xxxxxxxxxxxxxxx
Cc: platform-driver-x86@xxxxxxxxxxxxxxx
Cc: linux-pm@xxxxxxxxxxxxxxx
Signed-off-by: Eduardo Valentin <edubezval@xxxxxxxxx>
---
Please ignore last version.

V1-> V2:
Cleaned the patch and remove unrelated changes.
---

drivers/acpi/thermal.c | 2 --
drivers/platform/x86/acerhdf.c | 1 -
drivers/thermal/imx_thermal.c | 1 -
drivers/thermal/of-thermal.c | 1 -
drivers/thermal/thermal_sysfs.c | 1 +
drivers/thermal/ti-soc-thermal/ti-thermal-common.c | 1 -
6 files changed, 1 insertion(+), 6 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..4602e2e 100644
--- a/drivers/thermal/of-thermal.c
+++ b/drivers/thermal/of-thermal.c
@@ -292,7 +292,6 @@ 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;
}
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);