[PATCH 4/4] drm/i915/dmc_wl: Enable the debugfs only with enable_dmc_wl_debugfs=1

[Luca Coelho]

On Fri, 2025-01-17 at 19:06 -0300, Gustavo Sousa wrote:
> We use a spinlock to protect DMC wakelock debugfs data, since it is also
> accessed by the core DMC wakelock logic. Taking the spinlock when the
> debugfs is not in use introduces a small but unnecessary penalty.
> 
> Since the debugfs functionality is only expected to be used for, uh,
> debugging sessions, let's protect it behind a module parameter
> enable_dmc_wl_debugfs. That way, we only take the lock if the feature
> was enabled in the first place.
> 
> Signed-off-by: Gustavo Sousa <gustavo.sousa at intel.com>
> ---

Looks good.  With a small optional nitpick below.

Reviewed-by: Luca Coelho <luciano.coelho at intel.com>

[...]
> diff --git a/drivers/gpu/drm/i915/display/intel_display_params.c b/drivers/gpu/drm/i915/display/intel_display_params.c
> index c4f1ab43fc0c..bc36d1b0ef87 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_params.c
> +++ b/drivers/gpu/drm/i915/display/intel_display_params.c
> @@ -479,9 +488,14 @@ void intel_dmc_wl_debugfs_log_untracked(struct intel_display *display, u32 offse
>  bool intel_dmc_wl_debugfs_offset_in_extra_ranges(struct intel_display *display, u32 offset)
>  {
>  	struct intel_dmc_wl_dbg *dbg = &display->wl.dbg;
> -	bool ret = false;
> +	bool ret;

Why not keep this as it was...

>  	unsigned long flags;
>  
> +	if (!display->params.enable_dmc_wl_debugfs)
> +		return false;
> +
> +	ret = false;
> +

...then you don't need to set it here, and can return ret in the if
above for consistency.

--
Cheers,
Luca.