SHRINKER_REGISTERING  212 mm/vmscan.c    	id = idr_alloc(&shrinker_idr, SHRINKER_REGISTERING, 0, 0, GFP_KERNEL);
SHRINKER_REGISTERING  620 mm/vmscan.c    		if (unlikely(!shrinker || shrinker == SHRINKER_REGISTERING)) {