PB_migrate 78 include/linux/mmzone.h #define NR_MIGRATETYPE_BITS (PB_migrate_end - PB_migrate + 1) PB_migrate 87 include/linux/mmzone.h BUILD_BUG_ON(PB_migrate_end - PB_migrate != 2); PB_migrate 31 include/linux/pageblock-flags.h PB_migrate_end = PB_migrate + 3 - 1,