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

From: Zhang Rui <rui.zhang@intel.com>
To: Eduardo Valentin <edubezval@gmail.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: [PATCHv4 1/1] thermal: core: call thermal_zone_device_update() after mode update
Date: Wed, 29 Jun 2016 14:23:22 +0800	[thread overview]
Message-ID: <1467181402.2194.9.camel@intel.com> (raw)
In-Reply-To: <1466607798-30025-1-git-send-email-edubezval@gmail.com>

Hi, Eduardo,

as the locking patch set has not been in upstream yet, you should
either fold this fix into patch 02/15, or rebase your locking patch
series on top of this fix.

thanks,
rui

On 三, 2016-06-22 at 08:03 -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>
> ---
> 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);
>  