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

[Zi Yan]

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@xxxxxxxxxx>
> ---
>  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.