drm/i915: Track the rpm wakerefs for error handling

Keep hold of the local wakeref used in error handling, to cancel
the tracking upon release so that leaks can be identified.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-4-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/i915_irq.c

@@ -3291,6 +3291,7 @@ void i915_handle_error(struct drm_i915_private *dev_priv,
 		       const char *fmt, ...)
 {
 	struct intel_engine_cs *engine;
+	intel_wakeref_t wakeref;
 	unsigned int tmp;
 	char error_msg[80];
 	char *msg = NULL;
@@ -3312,7 +3313,7 @@ void i915_handle_error(struct drm_i915_private *dev_priv,
 	 * isn't the case at least when we get here by doing a
 	 * simulated reset via debugfs, so get an RPM reference.
 	 */
-	intel_runtime_pm_get(dev_priv);
+	wakeref = intel_runtime_pm_get(dev_priv);
 
 	engine_mask &= INTEL_INFO(dev_priv)->ring_mask;
 
@@ -3374,7 +3375,7 @@ void i915_handle_error(struct drm_i915_private *dev_priv,
 	wake_up_all(&dev_priv->gpu_error.reset_queue);
 
 out:
-	intel_runtime_pm_put_unchecked(dev_priv);
+	intel_runtime_pm_put(dev_priv, wakeref);
 }
 
 /* Called from drm generic code, passed 'crtc' which