[PATCH] drm/amd/amdgpu: Add a GPU_LOAD entry to sysfs

[Tom St Denis]

On 06/20/2018 10:37 AM, Abramov, Slava wrote:
> I see some functions in amdgpu_pm.c have function level documentation, 
> so that it would be good to have this for newly added functions.

Sure I can add some comments/docs.

> Another comment is inline.
> 
> 
>>From: amd-gfx <amd-gfx-bounces at lists.freedesktop.org> on behalf of Tom St Denis <tom.stdenis at amd.com>
> 
>  >Sent: Wednesday, June 20, 2018 8:31 AM
>  >To: amd-gfx at lists.freedesktop.org
>  >Cc: StDenis, Tom
>  >Subject: [PATCH] drm/amd/amdgpu: Add a GPU_LOAD entry to sysfs
>  >
>  >This adds what should be a stable interface to read GPU
>  >load from userspace.
>  >
>  >Signed-off-by: Tom St Denis <tom.stdenis at amd.com>
>  >---
>  > drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c | 41 
> ++++++++++++++++++++++++++++++++++
>  > 1 file changed, 41 insertions(+)
>  >
>  >diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c 
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
>  >index 113edffb5960..d57b414ac228 100644
>  >--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
>  >+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
>  >@@ -918,6 +918,37 @@ static ssize_t 
> amdgpu_set_pp_power_profile_mode(struct device *dev,
>  >         return -EINVAL;
>  > }
>  >
>  >+static ssize_t amdgpu_get_busy_level(struct device *dev,
>  >+               struct device_attribute *attr,
>  >+               char *buf)
>  >+{
>  >+       struct drm_device *ddev = dev_get_drvdata(dev);
>  >+       struct amdgpu_device *adev = ddev->dev_private;
>  >+       int r, value, size = sizeof(value);
>  >+
>  >+       /* sanity check PP is enabled */
>  >+       if (!(adev->powerplay.pp_funcs &&
>  >+             adev->powerplay.pp_funcs->read_sensor))
>  >+               return -EINVAL;
>  >+
>  >+       /* get the temperature */
> 
> Is load is the same thing as temperature?


Nope, there is a separate sensor for that but it is included in hwmon 
and Alex would rather not duplicate it.

GPU_LOAD is a value returned by firmware based on the RLC busy status (I 
think...).

Tom