STABLE_NODE_DUP_HEAD 345 mm/ksm.c return dup->head == STABLE_NODE_DUP_HEAD; STABLE_NODE_DUP_HEAD 352 mm/ksm.c dup->head = STABLE_NODE_DUP_HEAD; STABLE_NODE_DUP_HEAD 658 mm/ksm.c BUILD_BUG_ON(STABLE_NODE_DUP_HEAD <= &migrate_nodes); STABLE_NODE_DUP_HEAD 659 mm/ksm.c BUILD_BUG_ON(STABLE_NODE_DUP_HEAD >= &migrate_nodes + 1);