[Intel-gfx] [RFC 4/4] drm/i915: Expose RPS thresholds in sysfs

[Tvrtko Ursulin]

On 28/04/2023 09:14, Tvrtko Ursulin wrote:
> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> 
> User feedback indicates significant performance gains are possible in
> specific games with non default RPS up/down thresholds.
> 
> Expose these tunables via sysfs which will allow users to achieve best
> performance when running games and best power efficiency elsewhere.
> 
> Note this patch supports non GuC based platforms only.
> 
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> References: https://gitlab.freedesktop.org/drm/intel/-/issues/8389

[snip]

> diff --git a/drivers/gpu/drm/i915/gt/intel_rps.c b/drivers/gpu/drm/i915/gt/intel_rps.c
> index a5a7315f5ace..f790e81546ff 100644
> --- a/drivers/gpu/drm/i915/gt/intel_rps.c
> +++ b/drivers/gpu/drm/i915/gt/intel_rps.c
> @@ -2588,7 +2588,12 @@ static int rps_set_threshold(struct intel_rps *rps, u8 *threshold, u8 val)
>   	ret = mutex_lock_interruptible(&rps->lock);
>   	if (ret)
>   		return ret;
> -	*threshold = val;
> +	if (*threshold != val) {
> +		*threshold = val;
> +		intel_rps_set(rps, clamp(rps->cur_freq,
> +					 rps->min_freq_softlimit,
> +					 rps->max_freq_softlimit));
> +	}
>   	mutex_unlock(&rps->lock);
>   
>   	return 0;

This hunk belongs to a previous patch - moved locally.

Regards,

Tvrtko