Re: [PATCH 3/5] mm, page_owner: copy page owner info during migration

From: Joonsoo Kim
Date: Thu Nov 05 2015 - 03:23:53 EST


On Thu, Nov 05, 2015 at 09:17:33AM +0100, Vlastimil Babka wrote:
> On 11/05/2015 09:10 AM, Joonsoo Kim wrote:
> > On Wed, Nov 04, 2015 at 04:00:59PM +0100, Vlastimil Babka wrote:
> >> +void __copy_page_owner(struct page *oldpage, struct page *newpage)
> >> +{
> >> + struct page_ext *old_ext = lookup_page_ext(oldpage);
> >> + struct page_ext *new_ext = lookup_page_ext(newpage);
> >> + int i;
> >> +
> >> + new_ext->order = old_ext->order;
> >> + new_ext->gfp_mask = old_ext->gfp_mask;
> >> + new_ext->nr_entries = old_ext->nr_entries;
> >> +
> >> + for (i = 0; i < ARRAY_SIZE(new_ext->trace_entries); i++)
> >> + new_ext->trace_entries[i] = old_ext->trace_entries[i];
> >> +
> >> + __set_bit(PAGE_EXT_OWNER, &new_ext->flags);
> >> +}
> >> +
> >
> > Need to clear PAGE_EXT_OWNER bit in oldppage.
>
> Hm, I thought that the freeing of the oldpage, which follows the migration,
> would take care of that. And if it hit some bug and dump_page before being
> freed, we would still have some info to print?

Okay. I missed that.

Thanks.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/