Re: [HMM 12/15] mm/migrate: new memory migration helper for use with device memory v4

[Reza Arbab <arbab@linux.vnet.ibm.com>]

On Mon, May 22, 2017 at 12:52:03PM -0400, Jérôme Glisse wrote:
>This patch add a new memory migration helpers, which migrate memory
>backing a range of virtual address of a process to different memory
>(which can be allocated through special allocator). It differs from
>numa migration by working on a range of virtual address and thus by
>doing migration in chunk that can be large enough to use DMA engine
>or special copy offloading engine.
>
>Expected users are any one with heterogeneous memory where different
>memory have different characteristics (latency, bandwidth, ...). As
>an example IBM platform with CAPI bus can make use of this feature
>to migrate between regular memory and CAPI device memory. New CPU
>architecture with a pool of high performance memory not manage as
>cache but presented as regular memory (while being faster and with
>lower latency than DDR) will also be prime user of this patch.
>
>Migration to private device memory will be useful for device that
>have large pool of such like GPU, NVidia plans to use HMM for that.

Acked-by: Reza Arbab <arbab@linux.vnet.ibm.com>

-- 
Reza Arbab