[Intel-gfx] [PATCH] drm/i915: Always evaluate GEM_BUG_ON expression

[Chris Wilson]

On Fri, Nov 11, 2016 at 12:40:45PM +0200, Joonas Lahtinen wrote:
> Evaluate GEM_BUG_ON expression similar to actual BUG_ON even if
> DEBUG_GEM is disabled.
> 
> Cc: Arnd Bergmann <arnd at arndb.de>
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> Signed-off-by: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
> ---
>  drivers/gpu/drm/i915/i915_gem.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem.h b/drivers/gpu/drm/i915/i915_gem.h
> index 51ec793..d141676 100644
> --- a/drivers/gpu/drm/i915/i915_gem.h
> +++ b/drivers/gpu/drm/i915/i915_gem.h
> @@ -28,7 +28,7 @@
>  #ifdef CONFIG_DRM_I915_DEBUG_GEM
>  #define GEM_BUG_ON(expr) BUG_ON(expr)
>  #else
> -#define GEM_BUG_ON(expr) do { } while (0)
> +#define GEM_BUG_ON(expr) do { if (expr) {} } while(0)
>  #endif

Mentioned on irc, that I'm not that keen on having the side-effects
around. Suggestion was while (0) do { if (expr) {} } while (0)

But spot the dev who touched gem code without enabling the debug :-p
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre