SCAN_PAGE_NULL     18 include/trace/events/huge_memory.h 	EM( SCAN_PAGE_NULL,		"page_null")			\
SCAN_PAGE_NULL    560 mm/khugepaged.c 			result = SCAN_PAGE_NULL;
SCAN_PAGE_NULL   1168 mm/khugepaged.c 			result = SCAN_PAGE_NULL;