On Fri, Nov 13, 2020 at 05:14:52PM -0800, Andrew Morton wrote:
> On Fri, 13 Nov 2020 18:02:39 +1100 Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> wrote:
>
> > Hi all,
> >
> > After merging the akpm tree, today's linux-next build (i386 defconfig)
> > failed like this:
> >
> > mm/secretmem.c: In function 'secretmem_memcg_charge':
> > mm/secretmem.c:72:4: error: 'struct page' has no member named 'memcg_data'
> > 72 | p->memcg_data = page->memcg_data;
> > | ^~
> > mm/secretmem.c:72:23: error: 'struct page' has no member named 'memcg_data'
> > 72 | p->memcg_data = page->memcg_data;
> > | ^~
> > mm/secretmem.c: In function 'secretmem_memcg_uncharge':
> > mm/secretmem.c:86:4: error: 'struct page' has no member named 'memcg_data'
> > 86 | p->memcg_data = 0;
> > | ^~
> >
> > ...
> >
> > --- a/mm/secretmem.c
> > +++ b/mm/secretmem.c
> > @@ -69,7 +69,9 @@ static int secretmem_memcg_charge(struct page *page, gfp_t gfp, int order)
> > for (i = 1; i < nr_pages; i++) {
> > struct page *p = page + i;
> >
> > +#ifdef CONFIG_MEMCG
> > p->memcg_data = page->memcg_data;
> > +#endif
> > }
> >
> > return 0;
>
> Thanks, that'll work for now.
>
> I guess we're looking at adding a set_page_memcg() (I'd prefer
> page_memcg_set()).
>
> But probably these functions shouldn't be compiled at all if
> CONFIG_MEMCG=n.
My preference would be to put the entire function body in '#ifdef
CONFIG_MEMCG' here.
--
Sincerely yours,
Mike.
