[Intel-gfx] [PATCH 4/6] drm/i915: Add a wakeref getter for iff the wakeref is already active

[Mika Kuoppala]

Chris Wilson <chris at chris-wilson.co.uk> writes:

> For use in the next patch, we want to acquire a wakeref without having
> to wake the device up -- i.e. only acquire the engine wakeref if the
> engine is already active.
>

s/iff/if on the subject.

Reviewed-by: Mika Kuoppala <mika.kuoppala at linux.intel.com>

> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> ---
>  drivers/gpu/drm/i915/gt/intel_engine_pm.h |  7 ++++++-
>  drivers/gpu/drm/i915/intel_wakeref.h      | 15 +++++++++++++++
>  2 files changed, 21 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/gt/intel_engine_pm.h b/drivers/gpu/drm/i915/gt/intel_engine_pm.h
> index f3f5b031b4a1..7d057cdcd919 100644
> --- a/drivers/gpu/drm/i915/gt/intel_engine_pm.h
> +++ b/drivers/gpu/drm/i915/gt/intel_engine_pm.h
> @@ -11,7 +11,6 @@
>  #include "intel_wakeref.h"
>  
>  struct drm_i915_private;
> -struct intel_engine_cs;
>  
>  void intel_engine_pm_get(struct intel_engine_cs *engine);
>  void intel_engine_pm_put(struct intel_engine_cs *engine);
> @@ -22,6 +21,12 @@ intel_engine_pm_is_awake(const struct intel_engine_cs *engine)
>  	return intel_wakeref_is_active(&engine->wakeref);
>  }
>  
> +static inline bool
> +intel_engine_pm_get_if_awake(struct intel_engine_cs *engine)
> +{
> +	return intel_wakeref_get_if_active(&engine->wakeref);
> +}
> +
>  void intel_engine_park(struct intel_engine_cs *engine);
>  
>  void intel_engine_init__pm(struct intel_engine_cs *engine);
> diff --git a/drivers/gpu/drm/i915/intel_wakeref.h b/drivers/gpu/drm/i915/intel_wakeref.h
> index f74272770a5c..1d6f5986e4e5 100644
> --- a/drivers/gpu/drm/i915/intel_wakeref.h
> +++ b/drivers/gpu/drm/i915/intel_wakeref.h
> @@ -71,6 +71,21 @@ intel_wakeref_get(struct intel_runtime_pm *rpm,
>  	return 0;
>  }
>  
> +/**
> + * intel_wakeref_get_if_in_use: Acquire the wakeref
> + * @wf: the wakeref
> + *
> + * Acquire a hold on the wakeref, but only if the wakeref is already
> + * active.
> + *
> + * Returns: true if the wakeref was acquired, false otherwise.
> + */
> +static inline bool
> +intel_wakeref_get_if_active(struct intel_wakeref *wf)
> +{
> +	return atomic_inc_not_zero(&wf->count);
> +}
> +
>  /**
>   * intel_wakeref_put: Release the wakeref
>   * @i915: the drm_i915_private device
> -- 
> 2.20.1