Re: [PATCH v3 1/4] mm/page_isolation: make page isolation a standalone bit.

Johannes Weiner
2025-05-08T21:14:02Z

On Thu, May 08, 2025 at 04:22:43PM -0400, Zi Yan wrote:
> On 7 May 2025, at 17:10, Zi Yan wrote:
>
> > During page isolation, the original migratetype is overwritten, since
> > MIGRATE_* are enums and stored in pageblock bitmaps. Change
> > MIGRATE_ISOLATE to be stored a standalone bit, PB_migrate_isolate, like
> > PB_migrate_skip, so that migratetype is not lost during pageblock
> > isolation. pageblock bits needs to be word aligned, so expand
> > the number of pageblock bits from 4 to 8 and make PB_migrate_isolate bit 7.
> >
> > Signed-off-by: Zi Yan <ziy@nvidia.com>

Acked-by: Johannes Weiner <hannes@cmpxchg.org>

> > ---
> > include/linux/mmzone.h | 17 ++++++++++----
> > include/linux/page-isolation.h | 2 +-
> > include/linux/pageblock-flags.h | 33 +++++++++++++++++++++++++-
> > mm/page_alloc.c | 41 ++++++++++++++++++++++++++++++++-
> > 4 files changed, 86 insertions(+), 7 deletions(-)
> >
>
> Here is the fixup 1/3 to address Johannes’ comments.

Thanks!