drm/i915: Suppress busy status for engines if wedged

If the driver is wedged, HW state may be very inconsistent and
report that it is still busy, even though we have stopped using it. This
can lead to a double *ERROR* rather than a graceful cleanup after
wedging.

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/20170330145041.9005-2-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index cb61cec26db50ec7ecbfdff95ff9ebb0d6bda600..7165f314f830422aa2b4ec9a58eb1cd001bf3f79 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -3112,9 +3112,7 @@ i915_gem_idle_work_handler(struct work_struct *work)
         * Wait for last execlists context complete, but bail out in case a
         * new request is submitted.
         */
-       wait_for(READ_ONCE(dev_priv->gt.active_requests) ||
-                intel_engines_are_idle(dev_priv),
-                10);
+       wait_for(intel_engines_are_idle(dev_priv), 10);
        if (READ_ONCE(dev_priv->gt.active_requests))
                return;
 

diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
index 1fb97e8401de0fbc3beddbdd18be1b91303fe81d..854e8e0c836bd2099c1cfcb72e12e3ec5ff21915 100644 (file)
--- a/drivers/gpu/drm/i915/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/intel_engine_cs.c
@@ -1111,6 +1111,15 @@ bool intel_engines_are_idle(struct drm_i915_private *dev_priv)
        struct intel_engine_cs *engine;
        enum intel_engine_id id;
 
+       if (READ_ONCE(dev_priv->gt.active_requests))
+               return false;
+
+       /* If the driver is wedged, HW state may be very inconsistent and
+        * report that it is still busy, even though we have stopped using it.
+        */
+       if (i915_terminally_wedged(&dev_priv->gpu_error))
+               return true;
+
        for_each_engine(engine, dev_priv, id) {
                if (!intel_engine_is_idle(engine))
                        return false;