linux-master/mm/vmscan.c

3103 	unsigned long new_flags, old_flags = READ_ONCE(folio->flags);
3110 		if (!(old_flags & LRU_GEN_MASK)) {
3112 			new_flags = old_flags | BIT(PG_referenced);
3116 		new_flags = old_flags & ~(LRU_GEN_MASK | LRU_REFS_MASK | LRU_REFS_FLAGS);
3118 	} while (!try_cmpxchg(&folio->flags, &old_flags, new_flags));
3120 	return ((old_flags & LRU_GEN_MASK) >> LRU_GEN_PGOFF) - 1;
3129 	unsigned long new_flags, old_flags = READ_ONCE(folio->flags);
3131 	VM_WARN_ON_ONCE_FOLIO(!(old_flags & LRU_GEN_MASK), folio);
3134 		new_gen = ((old_flags & LRU_GEN_MASK) >> LRU_GEN_PGOFF) - 1;
3141 		new_flags = old_flags & ~(LRU_GEN_MASK | LRU_REFS_MASK | LRU_REFS_FLAGS);
3146 	} while (!try_cmpxchg(&folio->flags, &old_flags, new_flags));