Re: [PATCH 0/4] mm/mm_init: simplify deferred init of struct pages

From: Mike Rapoport
Date: Fri Aug 22 2025 - 01:55:35 EST


On Mon, Aug 18, 2025 at 09:46:11AM +0300, Mike Rapoport wrote:
> From: "Mike Rapoport (Microsoft)" <rppt@xxxxxxxxxx>
>
> Hi,
>
> These patches simplify deferred initialization of the memory map.
>
> Beside nice negative diffstat I measured 3ms reduction in the
> initialization of deferred pages on single node system with 64GiB of RAM.
>
> I don't have access to large memory machines, so I'd really appreciate
> testing of these patches on them to make sure there's no regression there.
>
> The patches are also available at git:
> https://git.kernel.org/pub/scm/linux/kernel/git/rppt/linux.git/log/?h=deferred-memmap-init/v1
>
> Mike Rapoport (Microsoft) (4):
> mm/mm_init: use deferred_init_memmap_chunk() in deferred_grow_zone()
> mm/mm_init: deferred_init_memmap: use a job per zone
> mm/mm_init: drop deferred_init_maxorder()
> memblock: drop for_each_free_mem_pfn_range_in_zone_from()

I've added those to memblock tree

> .clang-format | 1 -
> include/linux/memblock.h | 22 -----
> mm/memblock.c | 64 -------------
> mm/mm_init.c | 195 +++++++++++++--------------------------
> 4 files changed, 62 insertions(+), 220 deletions(-)
>
>
> base-commit: 8f5ae30d69d7543eee0d70083daf4de8fe15d585
> --
> 2.50.1
>

--
Sincerely yours,
Mike.