Re: [External] [RFC PATCH v1 3/6] mm, zone_type: create ZONE_NVM and fill into GFP_ZONE_TABLE

From: Randy Dunlap
Date: Tue May 08 2018 - 00:43:56 EST


On 05/07/2018 07:33 PM, Huaisheng HS1 Ye wrote:
> diff --git a/mm/Kconfig b/mm/Kconfig
> index c782e8f..5fe1f63 100644
> --- a/mm/Kconfig
> +++ b/mm/Kconfig
> @@ -687,6 +687,22 @@ config ZONE_DEVICE
>
> +config ZONE_NVM
> + bool "Manage NVDIMM (pmem) by memory management (EXPERIMENTAL)"
> + depends on NUMA && X86_64

Hi,
I'm curious why this depends on NUMA. Couldn't it be useful in non-NUMA
(i.e., UMA) configs?

Thanks.

> + depends on HAVE_MEMBLOCK_NODE_MAP
> + depends on HAVE_MEMBLOCK
> + depends on !IA32_EMULATION
> + default n
> +
> + help
> + This option allows you to use memory management subsystem to manage
> + NVDIMM (pmem). With it mm can arrange NVDIMMs into real physical zones
> + like NORMAL and DMA32. That means buddy system and swap can be used
> + directly to NVDIMM zone. This feature is beneficial to recover
> + dirty pages from power fail or system crash by storing write cache
> + to NVDIMM zone.



--
~Randy