Re: [PATCHv4 1/1] thermal: core: call thermal_zone_device_update() after mode update

Darren Hart
2016-06-23T04:52:07Z

On Wed, Jun 22, 2016 at 08:03:18AM -0700, 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.
>
> 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>

+Peter Feuerer <peter@piie.net>

Peter, any concerns regarding the acerhdf driver?

> ---
> Hello,
>
> V3->V4:
> - ti-soc: Removed extra locking from TI SoC in set_mode
> - ACPI: Kept the update on check as it is called on other places
>
> BR,
>
> Eduardo
>
> drivers/acpi/thermal.c | 1 -
> drivers/platform/x86/acerhdf.c | 1 -
> drivers/thermal/imx_thermal.c | 1 -
> drivers/thermal/of-thermal.c | 5 -----
> drivers/thermal/thermal_sysfs.c | 1 +
> drivers/thermal/ti-soc-thermal/ti-thermal-common.c | 5 -----
> 6 files changed, 1 insertion(+), 13 deletions(-)
>
> diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
> index 82707f9..03c3460 100644
> --- a/drivers/acpi/thermal.c
> +++ b/drivers/acpi/thermal.c
> @@ -581,7 +581,6 @@ static int thermal_set_mode(struct thermal_zone_device *thermal,
> ACPI_DEBUG_PRINT((ACPI_DB_INFO,
> "%s kernel ACPI thermal control\n",
> tz->tz_enabled ? "Enable" : "Disable"));
> - acpi_thermal_check(tz);
> }
> return 0;
> }
> 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..95c47da 100644
> --- a/drivers/thermal/of-thermal.c
> +++ b/drivers/thermal/of-thermal.c
> @@ -282,17 +282,12 @@ static int of_thermal_set_mode(struct thermal_zone_device *tz,
> {
> struct __thermal_zone *data = tz->devdata;
>
> - mutex_lock(&tz->lock);
> -
> if (mode == THERMAL_DEVICE_ENABLED)
> tz->polling_delay = data->polling_delay;
> else
> tz->polling_delay = 0;
>
> - 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..5dce053 100644
> --- a/drivers/thermal/ti-soc-thermal/ti-thermal-common.c
> +++ b/drivers/thermal/ti-soc-thermal/ti-thermal-common.c
> @@ -193,19 +193,14 @@ static int ti_thermal_set_mode(struct thermal_zone_device *thermal,
> return 0;
> }
>
> - mutex_lock(&data->ti_thermal->lock);
> -
> if (mode == THERMAL_DEVICE_ENABLED)
> data->ti_thermal->polling_delay = FAST_TEMP_MONITORING_RATE;
> else
> data->ti_thermal->polling_delay = 0;
>
> - mutex_unlock(&data->ti_thermal->lock);
> -
> 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
>
>

--
Darren Hart
Intel Open Source Technology Center