drm/mm: Split up long running selftests with cond_resched()

Scatter a few cond_resched() in between phases of the drm_mm selftests
to try and prevent us incurring the wrath of the NMI watchdog.

Signed-off-by: Chris Wilson <[e-mail]>
Cc: Joonas Lahtinen <[e-mail]>
Reviewed-by: Joonas Lahtinen <[e-mail]>
Signed-off-by: Daniel Vetter <[e-mail]>
Link: http://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/selftests/test-drm_mm.c

···
 		ret = __igt_reserve(count, size + 1);
 		if (ret)
 			return ret;
+
+		cond_resched();
 	}
 
 	return 0;
···
 			return ret;
 
 		ret = __igt_insert(count, size + 1, false);
+		if (ret)
+			return ret;
+
+		cond_resched();
 	}
 
 	return 0;
···
 			return ret;
 
 		ret = __igt_insert(count, size + 1, true);
+		if (ret)
+			return ret;
+
+		cond_resched();
 	}
 
 	return 0;
···
 		ret = __igt_insert_range(count, size, max/4+1, 3*max/4-1);
 		if (ret)
 			return ret;
+
+		cond_resched();
 	}
 
 	return 0;
···
 		drm_mm_for_each_node_safe(node, next, &mm)
 			drm_mm_remove_node(node);
 		DRM_MM_BUG_ON(!drm_mm_clean(&mm));
+		cond_resched();
 	}
 
 	ret = 0;
···
 			       align, bit);
 			goto out;
 		}
+
+		cond_resched();
 	}
 
 	ret = 0;
···
 				goto out;
 			}
 		}
+
+		cond_resched();
 	}
 
 	ret = 0;
···
 				goto out;
 			}
 		}
+
+		cond_resched();
 	}
 
 	ret = 0;
···
 		drm_mm_for_each_node_safe(node, next, &mm)
 			drm_mm_remove_node(node);
 		DRM_MM_BUG_ON(!drm_mm_clean(&mm));
+		cond_resched();
 	}
 
 	ret = 0;
···
 		drm_mm_for_each_node_safe(node, next, &mm)
 			drm_mm_remove_node(node);
 		DRM_MM_BUG_ON(!drm_mm_clean(&mm));
+		cond_resched();
 	}
 
 	ret = 0;
···
 			drm_mm_remove_node(node);
 			kfree(node);
 		}
+
+		cond_resched();
 	}
 
 	ret = 0;
···
 		}
 	}
 
+	cond_resched();
 	return 0;
 }
 
···
 				goto out;
 			}
 		}
+
+		cond_resched();
 	}
 
 	ret = 0;
···
 				goto out;
 			}
 		}
+
+		cond_resched();
 	}
 
 	ret = 0;