Re: [PATCH 1/2] zsmalloc: do not scan for allocated objects in empty zspage

From: Sergey Senozhatsky
Date: Fri Jun 23 2023 - 22:29:29 EST


On (23/06/23 10:49), Alexey Romanov wrote:
> > +static bool zspage_empty(struct zspage *zspage)
> > +{
> > + return get_zspage_inuse(zspage) == 0;
> > +}
> > +
> > /**
> > * zs_lookup_class_index() - Returns index of the zsmalloc &size_class
> > * that hold objects of the provided size.
> > @@ -1625,6 +1630,10 @@ static void migrate_zspage(struct zs_pool *pool, struct size_class *class,
> > obj_idx++;
> > record_obj(handle, free_obj);
> > obj_free(class->size, used_obj);
> > +
> > + /* Stop if there are no more objects to migrate */
> > + if (zspage_empty(get_zspage(s_page)))
> > + break;
> > }
> >
> > /* Remember last position in this iteration */
> > --
> > 2.41.0.162.gfafddb0af9-goog
> >
>
> I think we can add similar check in zs_reclaim_page() function.
> There we also scan zspage to find the allocated object.

LRU was moved to zswap, so zs_reclaim_page() doesn't exist any longer
(in linux-next).