2015-12-30 10:38:51

by Leo Yan

Subject: [PATCH v2] thermal: re-calculate k_po/k_pu when update sustainable power

k_po/k_pu are in essence ratio values compared with sustainable power.
So when update sustainable power, we can recalculate k_po/k_pu simply
with below formula:

sustainable_power(new)
k_p(new) = ---------------------- * k_p(old)
sustainable_power(old)

Signed-off-by: Leo Yan <[email protected]>
---
drivers/thermal/thermal_core.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index d9e525c..223f8df 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -908,7 +908,7 @@ sustainable_power_store(struct device *dev, struct device_attribute *devattr,
const char *buf, size_t count)
{
struct thermal_zone_device *tz = to_thermal_zone(dev);
- u32 sustainable_power;
+ u32 sustainable_power, old_val;

if (!tz->tzp)
return -EIO;
@@ -916,8 +916,12 @@ sustainable_power_store(struct device *dev, struct device_attribute *devattr,
if (kstrtou32(buf, 10, &sustainable_power))
return -EINVAL;

+ old_val = tz->tzp->sustainable_power;
+
tz->tzp->sustainable_power = sustainable_power;

+ tz->tzp->k_po = (tz->tzp->k_po * sustainable_power) / old_val;
+ tz->tzp->k_pu = (tz->tzp->k_pu * sustainable_power) / old_val;
return count;
}
static DEVICE_ATTR(sustainable_power, S_IWUSR | S_IRUGO, sustainable_power_show,
--
1.9.1

2015-12-31 17:21:35

by Eduardo Valentin

Subject: Re: [PATCH v2] thermal: re-calculate k_po/k_pu when update sustainable power

On Wed, Dec 30, 2015 at 06:38:40PM +0800, Leo Yan wrote:
> k_po/k_pu are in essence ratio values compared with sustainable power.
> So when update sustainable power, we can recalculate k_po/k_pu simply
> with below formula:
>
> sustainable_power(new)
> k_p(new) = ---------------------- * k_p(old)
> sustainable_power(old)
>
> Signed-off-by: Leo Yan <[email protected]>
> ---
> drivers/thermal/thermal_core.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
> index d9e525c..223f8df 100644
> --- a/drivers/thermal/thermal_core.c
> +++ b/drivers/thermal/thermal_core.c
> @@ -908,7 +908,7 @@ sustainable_power_store(struct device *dev, struct device_attribute *devattr,
> const char *buf, size_t count)
> {
> struct thermal_zone_device *tz = to_thermal_zone(dev);
> - u32 sustainable_power;
> + u32 sustainable_power, old_val;
>
> if (!tz->tzp)
> return -EIO;
> @@ -916,8 +916,12 @@ sustainable_power_store(struct device *dev, struct device_attribute *devattr,
> if (kstrtou32(buf, 10, &sustainable_power))
> return -EINVAL;
>
> + old_val = tz->tzp->sustainable_power;
> +
> tz->tzp->sustainable_power = sustainable_power;
>
> + tz->tzp->k_po = (tz->tzp->k_po * sustainable_power) / old_val;
> + tz->tzp->k_pu = (tz->tzp->k_pu * sustainable_power) / old_val;

I believe this has to be done by the governor. These properties are
power_allocator specific. thermal_core should not really care about
them.

> return count;
> }
> static DEVICE_ATTR(sustainable_power, S_IWUSR | S_IRUGO, sustainable_power_show,
> --
> 1.9.1
>

2016-01-01 00:03:55

by Leo Yan

Subject: Re: [PATCH v2] thermal: re-calculate k_po/k_pu when update sustainable power

Hi Eduardo,

Thanks for review.

On Thu, Dec 31, 2015 at 09:21:26AM -0800, Eduardo Valentin wrote:
> On Wed, Dec 30, 2015 at 06:38:40PM +0800, Leo Yan wrote:
> > k_po/k_pu are in essence ratio values compared with sustainable power.
> > So when update sustainable power, we can recalculate k_po/k_pu simply
> > with below formula:
> >
> > sustainable_power(new)
> > k_p(new) = ---------------------- * k_p(old)
> > sustainable_power(old)
> >
> > Signed-off-by: Leo Yan <[email protected]>
> > ---
> > drivers/thermal/thermal_core.c | 6 +++++-
> > 1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
> > index d9e525c..223f8df 100644
> > --- a/drivers/thermal/thermal_core.c
> > +++ b/drivers/thermal/thermal_core.c
> > @@ -908,7 +908,7 @@ sustainable_power_store(struct device *dev, struct device_attribute *devattr,
> > const char *buf, size_t count)
> > {
> > struct thermal_zone_device *tz = to_thermal_zone(dev);
> > - u32 sustainable_power;
> > + u32 sustainable_power, old_val;
> >
> > if (!tz->tzp)
> > return -EIO;
> > @@ -916,8 +916,12 @@ sustainable_power_store(struct device *dev, struct device_attribute *devattr,
> > if (kstrtou32(buf, 10, &sustainable_power))
> > return -EINVAL;
> >
> > + old_val = tz->tzp->sustainable_power;
> > +
> > tz->tzp->sustainable_power = sustainable_power;
> >
> > + tz->tzp->k_po = (tz->tzp->k_po * sustainable_power) / old_val;
> > + tz->tzp->k_pu = (tz->tzp->k_pu * sustainable_power) / old_val;
>
> I believe this has to be done by the governor. These properties are
> power_allocator specific. thermal_core should not really care about
> them.

Okay, I will try to update these properties in power_allocator.c.
Javi, do you think this is fine for you?

Thanks,
Leo Yan

>
> > return count;
> > }
> > static DEVICE_ATTR(sustainable_power, S_IWUSR | S_IRUGO, sustainable_power_show,
> > --
> > 1.9.1
> >