drm/i915: Integrate i915_sw_fence with debugobjects

Add the tracking required to enable debugobjects for fences to improve
error detection in BAT. The debugobject interface lets us track the
lifetime and phases of the fences even while being embedded into larger
structs, i.e. to check they are not used after they have been released.

v2: Don't populate the stubs, debugobjects checks for a NULL pointer and
treats it equivalently.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161125131718.20978-4-chris@chris-wilson.co.uk

1 files changed, 13 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/Kconfig.debug b/drivers/gpu/drm/i915/Kconfig.debug
index 51ba630a134b..a6c69b8cb1d2 100644
--- a/drivers/gpu/drm/i915/Kconfig.debug
+++ b/drivers/gpu/drm/i915/Kconfig.debug
@@ -22,6 +22,7 @@ config DRM_I915_DEBUG
         select X86_MSR # used by igt/pm_rpm
         select DRM_VGEM # used by igt/prime_vgem (dmabuf interop checks)
         select DRM_DEBUG_MM if DRM=y
+        select DRM_I915_SW_FENCE_DEBUG_OBJECTS if DRM_I915=y
         default n
         help
           Choose this option to turn on extra driver debugging that may affect
@@ -43,3 +44,15 @@ config DRM_I915_DEBUG_GEM
 
           If in doubt, say "N".
 
+config DRM_I915_SW_FENCE_DEBUG_OBJECTS
+        bool "Enable additional driver debugging for fence objects"
+        depends on DRM_I915=y
+        select DEBUG_OBJECTS
+        default n
+        help
+          Choose this option to turn on extra driver debugging that may affect
+          performance but will catch some internal issues.
+
+          Recommended for driver developers only.
+
+          If in doubt, say "N".