Re: [PATCH v1 01/12] f2fs: cache: implement metadata cache

[Wenjie Qi]

Hi Chao,

> static void f2fs_zone_write_end_io(struct bio *bio)
> {
> 	bio->bi_private = io->bi_private;
> 	complete(&io->zone_wait);
> 	if (io->fio.is_cache)
> 		f2fs_cache_write_end_io(bio);
> 	else
> 		f2fs_write_end_io(bio);
> }

`io->fio` is updated when the next BIO is prepared.  Once
`complete(&io->zone_wait)` wakes the waiting writer, that preparation can
run before this callback reads `io->fio.is_cache`.

Is there another serialization condition that keeps `io->fio.is_cache`
unchanged between `complete()` and this read?