Re: [RFC PATCH 2/2] zsmalloc: chain-length configuration should consider other metrics

[Sergey Senozhatsky]

On (26/01/12 13:01), Herbert Xu wrote:
> On Fri, Jan 09, 2026 at 04:02:51PM +0000, Yosry Ahmed wrote:
> > 
> > Herbert, do you mind taking a look at this? It looks sane to me except
> > for one question below.
> 
> Looks alright to me too.
> 
> > > +		size_t sizes[2];
> > > +
> > > +		/* this object spans two pages */
> > > +		sizes[0] = PAGE_SIZE - off;
> > > +		sizes[1] = mem_len - sizes[0];
> > > +
> > > +		sg_init_table(sg, 2);
> > > +		sg_set_page(sg, zpdesc_page(zpdesc), sizes[0], off);
> > > +
> > > +		zpdesc = get_next_zpdesc(zpdesc);
> > > +		sg = sg_next(sg);
> > 
> > Is this stateful? Will the SG list be returned pointing at the second
> > page now?
> 
> It makes no difference because we just called sg_init_table(sg, 2),
> so sg_next(sg) is equivalent to &sg[1].

I did it this way for (sort of) consistency: sg next follows zpdesc next.