Re: [PATCH v2 0/7] Allocate memmap from hotadded memory (per device)

From: Oscar Salvador
Date: Mon Feb 22 2021 - 06:16:00 EST


On Wed, Feb 17, 2021 at 11:18:59AM +0100, Oscar Salvador wrote:
> On Tue, Feb 09, 2021 at 02:38:47PM +0100, Oscar Salvador wrote:
> > Hi,
> >
> > here is v2.
> >
> > Changes from v1 -> v2
> > - Addressed feedback from David
> > - Fence off the feature in case struct page size is not
> > multiple of PMD size or pageblock alignment cannot be guaranted
> > - Tested on x86_64 small and large memory_blocks
> > - Tested on arm64 4KB and 64KB page sizes (for some reason I cannot boot
> > my VM with 16KB page size).
> >
> > Arm64 with 4KB page size behaves like x86_64 after [1], which made section
> > size smaller.
> > With 64KB, the feature gets fenced off due to pageblock alignment.
> >
> > Changes from RFCv3 -> v1:
> > - Addressed feedback from David
> > - Re-order patches
> >
> > Changes from v2 -> v3 (RFC):
> > - Re-order patches (Michal)
> > - Fold "mm,memory_hotplug: Introduce MHP_MEMMAP_ON_MEMORY" in patch#1
> > - Add kernel boot option to enable this feature (Michal)
> >
> > Changes from v1 -> v2 (RFC):
> > - Addressed feedback provided by David
> > - Add a arch_support_memmap_on_memory to be called
> > from mhp_supports_memmap_on_memory, as atm,
> > only ARM, powerpc and x86_64 have altmat support.
> >
> > [1] https://lore.kernel.org/lkml/cover.1611206601.git.sudaraja@xxxxxxxxxxxxxx/
>
> Let me refloat this one :-)

Kindly ping :-)



--
Oscar Salvador
SUSE L3