On Thu, 2025-01-16 at 15:51 +0800, Gao Xiang wrote:
> Hi Linxuan,
>
> On 2025/1/16 15:20, Chen Linxuan wrote:
> > Comments in file include/linux/shrinker.h says that
> > `count_objects` of `struct shrinker` should return SHRINK_EMPTY
> > when there are no objects to free.
> >
> > > If there are no objects to free, it should return SHRINK_EMPTY,
> > > while 0 is returned in cases of the number of freeable items cannot
> > > be determined or shrinker should skip this cache for this time
> > > (e.g., their number is below shrinkable limit).
>
> Thanks for the patch!
>
> Yeah, it seems that is the case. Yet it'd better to document
> what the impact if 0 is returned here if you know more..
Sorry, I have no idea about that.
>
> >
> > Signed-off-by: Chen Linxuan <chenlinx...@uniontech.com>
> > ---
> > fs/erofs/zutil.c | 4 +++-
> > 1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/fs/erofs/zutil.c b/fs/erofs/zutil.c
> > index 0dd65cefce33..682863fa9e1c 100644
> > --- a/fs/erofs/zutil.c
> > +++ b/fs/erofs/zutil.c
> > @@ -243,7 +243,9 @@ void erofs_shrinker_unregister(struct super_block *sb)
> > static unsigned long erofs_shrink_count(struct shrinker *shrink,
> > struct shrink_control *sc)
> > {
> > - return atomic_long_read(&erofs_global_shrink_cnt);
> > + unsigned long count = atomic_long_read(&erofs_global_shrink_cnt);
> > +
> > + return count ? count : SHRINK_EMPTY;
>
> I guess you could just use
>
> return atomic_long_read(&erofs_global_shrink_cnt) ?: SHRINK_EMPTY;
>
> Thanks,
> Gao Xiang
>
> > }
> >
> > static unsigned long erofs_shrink_scan(struct shrinker *shrink,
>
>
>
