drm/i915: add struct i915_ctx_hang_stats

To count context losses, add struct i915_ctx_hang_stats for
both i915_hw_context and drm_i915_file_private.
drm_i915_file_private is used when there is no context.

v2: renamed and cleaned up the struct (Chris Wilson, Ian Romanick)
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_dma.c

@@ -1814,7 +1814,7 @@ int i915_driver_open(struct drm_device *dev, struct drm_file *file)
 	struct drm_i915_file_private *file_priv;
 
 	DRM_DEBUG_DRIVER("\n");
-	file_priv = kmalloc(sizeof(*file_priv), GFP_KERNEL);
+	file_priv = kzalloc(sizeof(*file_priv), GFP_KERNEL);
 	if (!file_priv)
 		return -ENOMEM;
 

drivers/gpu/drm/i915/i915_drv.h

@@ -508,6 +508,13 @@ struct i915_hw_ppgtt {
 	void (*cleanup)(struct i915_hw_ppgtt *ppgtt);
 };
 
+struct i915_ctx_hang_stats {
+	/* This context had batch pending when hang was declared */
+	unsigned batch_pending;
+
+	/* This context had batch active when hang was declared */
+	unsigned batch_active;
+};
 
 /* This must match up with the value previously used for execbuf2.rsvd1. */
 #define DEFAULT_CONTEXT_ID 0
@@ -518,6 +525,7 @@ struct i915_hw_context {
 	struct drm_i915_file_private *file_priv;
 	struct intel_ring_buffer *ring;
 	struct drm_i915_gem_object *obj;
+	struct i915_ctx_hang_stats hang_stats;
 };
 
 enum no_fbc_reason {
@@ -1377,6 +1385,8 @@ struct drm_i915_file_private {
 		struct list_head request_list;
 	} mm;
 	struct idr context_idr;
+
+	struct i915_ctx_hang_stats hang_stats;
 };
 
 #define INTEL_INFO(dev)	(((struct drm_i915_private *) (dev)->dev_private)->info)