Messages in this thread | | | From | "Huang, Ying" <> | Subject | Re: [PATCH v2 2/2] mm: Remember young/dirty bit for page migrations | Date | Wed, 10 Aug 2022 08:53:49 +0800 |
| |
Peter Xu <peterx@redhat.com> writes:
> On Tue, Aug 09, 2022 at 04:40:12PM +0800, Huang, Ying wrote: [snip] > >> I don't find pte_dirty() is synced to PageDirty() as in >> try_to_migrate_one(). Is it a issue in the original code? > > I think it has? There is: > > /* Set the dirty flag on the folio now the pte is gone. */ > if (pte_dirty(pteval)) > folio_mark_dirty(folio); >
Sorry, my original words are confusing. Yes, there's dirty bit syncing in try_to_migrate_one(). But I don't find that in migrate_device.c
$ grep dirty mm/migrate_device.c if (pte_soft_dirty(pte)) swp_pte = pte_swp_mksoft_dirty(swp_pte); if (pte_swp_soft_dirty(pte)) swp_pte = pte_swp_mksoft_dirty(swp_pte); entry = pte_mkwrite(pte_mkdirty(entry));
I guess that migrate_device.c is used to migrate between CPU visible page to CPU un-visible page (device visible), so the rule is different?
Best Regards, Huang, Ying
| |