Re: [Linux-nvdimm] another pmem variant V2

From: Ingo Molnar
Date: Wed Apr 01 2015 - 03:50:20 EST

* Dan Williams <dan.j.williams@xxxxxxxxx> wrote:

> On Tue, Mar 31, 2015 at 10:24 AM, Christoph Hellwig <hch@xxxxxx> wrote:
> > On Tue, Mar 31, 2015 at 06:44:56PM +0200, Ingo Molnar wrote:
> >> I'd be fine with that too - mind sending an updated series?
> >
> > I will send an updated one tonight or early tomorrow.
> >
> > Btw, do you want to keep the E820_PRAM name instead of E820_PMEM?
> > Seems like most people either don't care or prefer E820_PMEM. I'm
> > fine either way.
> FWIW, I like the idea of having a separate E820_PRAM name for
> type-12 memory vs future "can't yet disclose" UEFI memory type. The
> E820_PRAM type potentially has the property of being relegated to
> "legacy" NVDIMMs. We can later add E820_PMEM as a memory type that,
> for example, is not automatically backed by struct page. That said,
> I'm fine either way.

I agree that it's a minor detail, but I think the separation is
useful in two ways:

- We have a generic 'pmem' driver, but the low level, platform
specific RAM enumeration name does not use that name.

- 'E820_PRAM' is a more natural extension of 'E820_RAM'.

Later on we can then do a:


rename or so.


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