Re: [RFC PATCH v3 5/8] mm: page_isolation: check specified range for unmovable pages during isolation.

[David Hildenbrand]

On 05.01.22 22:47, Zi Yan wrote:
> From: Zi Yan <ziy@xxxxxxxxxx>
> 
> Enable set_migratetype_isolate() to check specified sub-range for
> unmovable pages during isolation. Page isolation is done
> at max(MAX_ORDER_NR_PAEGS, pageblock_nr_pages) granularity, but not all
> pages within that granularity are intended to be isolated. For example,
> alloc_contig_range(), which uses page isolation, allows ranges without
> alignment. This commit makes unmovable page check only look for
> interesting pages, so that page isolation can succeed for any
> non-overlapping ranges.

Are you handling if we start checking in the middle of a compound page
and actually have to lookup the head to figure out if movable or not?

> 
> has_unmovable_pages() is moved to mm/page_isolation.c since it is only
> used by page isolation.

Please move that into a separate patch upfront, makes this patch much
easier to review.

-- 
Thanks,

David / dhildenb