Re: [f2fs-dev] [PATCH v3 09/12] f2fs: cache: use compress cache

[Chao Yu]

On 8/28/26 20:00, Chao Yu wrote:
> On 8/27/26 04:04, Daeho Jeong wrote:
> > On Tue, Aug 25, 2026 at 6:03 AM Chao Yu via Linux-f2fs-devel
> > > +               f2fs_lock_cache(entry);
> > >
> > > -                       if (ino != folio_get_f2fs_data(folio)) {
> > > -                               folio_unlock(folio);
> > > -                               continue;
> > > -                       }
> > > -
> > > -                       generic_error_remove_folio(mapping, folio);
> > > -                       folio_unlock(folio);
> > > +               if (!f2fs_is_compress_cache(entry)) {
> >
> > How is this possible?
> > or if (!entry->cache)?
>
> I suffer a panic from f2fs_bug_on(sbi, !f2fs_is_compress_cache(entry)) here,
> it may suffer race condition w/ shrinker.

I changed like this, because:
1. we will never update entry->ino after initialization, so it's safe to
check w/o lock.
2. f2fs_truncate_cache() has checked entry->cache by itself, so it doesn't
need to check w/ f2fs_is_compress_cache() outside __f2fs_truncate_cache().

	for (i = 0; i < nr; i++) {
		struct f2fs_cached_block *entry = entries[i];

		index = entry->index + 1;

		if (entry->ino != ino)
			continue;

		f2fs_truncate_cache(entry, false);
	}

Let me know if you have any concern about this.

Thanks,