drm/atomic: Call ww_acquire_done after check phase is complete

We want to make sure that no one tries to acquire more locks and
states, and ww mutexes provide debug facilities for that. So use them.

v2: Only call acquire_done when ->atomic_check was successful to avoid
falling over an -EDEADLK (spotted by Maarten).

Cc: Rob Clark <robdclark@gmail.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 434915448ea0be99b7786c6daf2650cfb93b728a..1066e4b658cf9a341c1955fb34f82040a4be909c 100644 (file)
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -1230,6 +1230,9 @@ int drm_atomic_check_only(struct drm_atomic_state *state)
                }
        }
 
+       if (ret == 0)
+               ww_acquire_done(&state->acquire_ctx->ww_ctx);
+
        return ret;
 }
 EXPORT_SYMBOL(drm_atomic_check_only);