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

From: Keerthy <a0393675@ti.com>
To: Eduardo Valentin <edubezval@gmail.com>, Rui Zhang <rui.zhang@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Len Brown <lenb@kernel.org>, <linux-acpi@vger.kernel.org>,
	"Lee, Chun-Yi" <jlee@suse.com>,
	Darren Hart <dvhart@infradead.org>, Keerthy <j-keerthy@ti.com>,
	<linux-kernel@vger.kernel.org>, <linux-omap@vger.kernel.org>,
	<platform-driver-x86@vger.kernel.org>, <linux-pm@vger.kernel.org>
Subject: Re: [PATCHv2 1/1] thermal: core: call thermal_zone_device_update() after mode update
Date: Wed, 22 Jun 2016 15:03:45 +0530	[thread overview]
Message-ID: <576A5B79.7070209@ti.com> (raw)
In-Reply-To: <1466572546-12944-1-git-send-email-edubezval@gmail.com>

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@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>
> ---
> 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);
>
>