Re: [PATCH RESEND v2 4/6] mm/page_alloc: sort out the alloc_contig_range() gfp flags mess

From: Oscar Salvador
Date: Wed Dec 04 2024 - 04:00:48 EST


On Tue, Dec 03, 2024 at 10:47:30AM +0100, David Hildenbrand wrote:
> It's all a bit complicated for alloc_contig_range(). For example, we don't
> support many flags, so let's start bailing out on unsupported
> ones -- ignoring the placement hints, as we are already given the range
> to allocate.
>
> While we currently set cc.gfp_mask, in __alloc_contig_migrate_range() we
> simply create yet another GFP mask whereby we ignore the reclaim flags
> specify by the caller. That looks very inconsistent.
>
> Let's clean it up, constructing the gfp flags used for
> compaction/migration exactly once. Update the documentation of the
> gfp_mask parameter for alloc_contig_range() and alloc_contig_pages().
>
> Acked-by: Zi Yan <ziy@xxxxxxxxxx>
> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>

Reviewed-by: Oscar Salvador <osalvador@xxxxxxx>


--
Oscar Salvador
SUSE Labs