From mboxrd@z Thu Jan  1 00:00:00 1970
From: Robert Richter <robert.richter-M3mlKVOIwJVv6pq1l3V1OdBPR1lH4CV8@public.gmane.org>
Subject: Re: [PATCH v12 4/5] arm64, numa: Add NUMA support for arm64
 platforms.
Date: Mon, 29 Feb 2016 11:12:36 +0100
Message-ID: <20160229101236.GQ24726@rric.localdomain>
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 <56D0ACC4.1060605@caviumnetworks.com>
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To: Ganapatrao Kulkarni <gpkulkarni-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: David Daney <ddaney-M3mlKVOIwJVv6pq1l3V1OdBPR1lH4CV8@public.gmane.org>, Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>, Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>, "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" <devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Pawel Moll <pawel.moll-5wv7dgnIgG8@public.gmane.org>, Ian Campbell <ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg@public.gmane.org>, Matt Fleming <matt-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org>, Catalin Marinas <catalin.marinas-5wv7dgnIgG8@public.gmane.org>, Ard Biesheuvel <ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>, David Daney <david.daney-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org>, "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, David Daney <ddaney.cavm-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Kumar Gala <galak-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>, Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>, Ganapatrao Kulkarni <gkulkarni-M3mlKVOIwJVv6pq1l3V1OdBPR1lH4CV8@public.gmane.org>, Frank Rowand <frowand.list-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" <linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org>
List-Id: devicetree@vger.kernel.org

On 27.02.16 09:43:49, Ganapatrao Kulkarni wrote:
> On Sat, Feb 27, 2016 at 1:21 AM, David Daney <ddaney-M3mlKVOIwJVv6pq1l3V1OdBPR1lH4CV8@public.gmane.org> wrote:
> > On 02/26/2016 10:53 AM, Will Deacon wrote:

> >>> +static __init int numa_parse_early_param(char *opt)
> >>> +{
> >>> +       if (!opt)
> >>> +               return -EINVAL;
> >>> +       if (!strncmp(opt, "off", 3)) {
> >>> +               pr_info("%s\n", "NUMA turned off");
> >>> +               numa_off = 1;
> >>> +       }
> >>> +       return 0;
> >>> +}
> >>> +early_param("numa", numa_parse_early_param);
> >>
> >>
> >> Curious, but when is this option actually useful?
> >>
> >
> > Good point.  I will remove that bit, it was used as an aid in debugging
> > while bringing up the patch set.
> 
> this is handy in debugging new platforms.
> this boot argument option forces to boot as single node dummy system
> adding all resources to node0.

This is used to disable numa in a numa enabled kernel esp. for
debugging/enabling/booting single node systems. Same kernel parameter
as for x86 and other archs. Should not being removed.

-Robert