drm/exynos: add pid to g2d_runqueue_node

this patch adds pid to g2d_runqueue_node as member to identify
which process owns this node.

Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
diff --git a/drivers/gpu/drm/exynos/exynos_drm_g2d.c b/drivers/gpu/drm/exynos/exynos_drm_g2d.c
index 1065e90..dcbc4cb 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_g2d.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_g2d.c
@@ -122,6 +122,7 @@
 	struct list_head	list;
 	struct list_head	run_cmdlist;
 	struct list_head	event_list;
+	pid_t			pid;
 	struct completion	complete;
 	int			async;
 };
@@ -679,6 +680,7 @@
 	}
 
 	mutex_lock(&g2d->runqueue_mutex);
+	runqueue_node->pid = current->pid;
 	list_add_tail(&runqueue_node->list, &g2d->runqueue);
 	if (!g2d->runqueue_node)
 		g2d_exec_runqueue(g2d);