drm/i915: Use our own workqueue to avoid wedging the system along with the GPU.

Signed-off-by: Eric Anholt <[e-mail]>

drivers/gpu/drm/i915/i915_dma.c

···
 	if (ret)
 		goto out_iomapfree;
 
+	dev_priv->wq = create_workqueue("i915");
+	if (dev_priv->wq == NULL) {
+		DRM_ERROR("Failed to create our workqueue.\n");
+		ret = -ENOMEM;
+		goto out_iomapfree;
+	}
+
 	/* enable GEM by default */
 	dev_priv->has_gem = 1;
 
···
 	if (!I915_NEED_GFX_HWS(dev)) {
 		ret = i915_init_phys_hws(dev);
 		if (ret != 0)
-			goto out_iomapfree;
+			goto out_workqueue_free;
 	}
 
 	i915_get_mem_freq(dev);
···
 		ret = i915_load_modeset_init(dev, prealloc_size, agp_size);
 		if (ret < 0) {
 			DRM_ERROR("failed to init modeset\n");
-			goto out_rmmap;
+			goto out_workqueue_free;
 		}
 	}
 
···
 
 	return 0;
 
+out_workqueue_free:
+	destroy_workqueue(dev_priv->wq);
 out_iomapfree:
 	io_mapping_free(dev_priv->mm.gtt_mapping);
 out_rmmap:
···
 int i915_driver_unload(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	destroy_workqueue(dev_priv->wq);
 
 	io_mapping_free(dev_priv->mm.gtt_mapping);
 	if (dev_priv->mm.gtt_mtrr >= 0) {

drivers/gpu/drm/i915/i915_drv.h

···
 	spinlock_t error_lock;
 	struct drm_i915_error_state *first_error;
 	struct work_struct error_work;
+	struct workqueue_struct *wq;
 
 	/* Register state */
 	u8 saveLBB;

drivers/gpu/drm/i915/i915_gem.c

···
 	}
 
 	if (was_empty && !dev_priv->mm.suspended)
-		schedule_delayed_work(&dev_priv->mm.retire_work, HZ);
+		queue_delayed_work(dev_priv->wq, &dev_priv->mm.retire_work, HZ);
 	return seqno;
 }
 
···
 	i915_gem_retire_requests(dev);
 	if (!dev_priv->mm.suspended &&
 	    !list_empty(&dev_priv->mm.request_list))
-		schedule_delayed_work(&dev_priv->mm.retire_work, HZ);
+		queue_delayed_work(dev_priv->wq, &dev_priv->mm.retire_work, HZ);
 	mutex_unlock(&dev->struct_mutex);
 }
 

drivers/gpu/drm/i915/i915_irq.c

···
 		I915_WRITE(IIR, I915_RENDER_COMMAND_PARSER_ERROR_INTERRUPT);
 	}
 
-	schedule_work(&dev_priv->error_work);
+	queue_work(dev_priv->wq, &dev_priv->error_work);
 }
 
 irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
···
 			DRM_DEBUG("hotplug event received, stat 0x%08x\n",
 				  hotplug_status);
 			if (hotplug_status & dev_priv->hotplug_supported_mask)
-				schedule_work(&dev_priv->hotplug_work);
+				queue_work(dev_priv->wq,
+					   &dev_priv->hotplug_work);
 
 			I915_WRITE(PORT_HOTPLUG_STAT, hotplug_status);
 			I915_READ(PORT_HOTPLUG_STAT);