[Intel-gfx] [PATCH] drm/i915: throw __must_check at GEM_WARN_ON

[Matthew Auld]

GEM_WARN_ON is intended to be used as:

if (GEM_WARN_ON(expr))
	...

However this isn't clear since we just wrap WARN_ON, therefore throw a
warning if the result is ignored. For !DRM_I915_DEBUG_GEM builds this
should already be the case.

Suggested-by: Jani Nikula <jani.nikula at linux.intel.com>
Signed-off-by: Matthew Auld <matthew.auld at intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
Cc: Jani Nikula <jani.nikula at linux.intel.com>
Cc: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_gem.h | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.h b/drivers/gpu/drm/i915/i915_gem.h
index 8922344fc21b..760671119130 100644
--- a/drivers/gpu/drm/i915/i915_gem.h
+++ b/drivers/gpu/drm/i915/i915_gem.h
@@ -36,7 +36,14 @@
 		BUG(); \
 		} \
 	} while(0)
-#define GEM_WARN_ON(expr) WARN_ON(expr)
+
+static __always_inline bool __must_check __gem_warn_on(bool v)
+{
+	return WARN_ON(v);
+}
+
+/* To be used as: if (GEM_WARN_ON(expr)) */
+#define GEM_WARN_ON(expr) __gem_warn_on(expr)
 
 #define GEM_DEBUG_DECL(var) var
 #define GEM_DEBUG_EXEC(expr) expr
-- 
2.14.3