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Date: Thu, 26 Mar 2015 13:22:59 +0000
From: Russell King - ARM Linux <linux@arm.linux.org.uk>
To: Mel Gorman <mgorman@suse.de>
Cc: Gregory Fong <gregory.0xf0@gmail.com>,
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Subject: Re: [PATCH] ARM: print cma-reserved pages from show_mem
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On Thu, Mar 26, 2015 at 12:30:29PM +0000, Mel Gorman wrote:
> On Thu, Mar 26, 2015 at 11:46:12AM +0000, Russell King - ARM Linux wrote:
> > <SNIP>
> > 
> > Looking at Mel's commit, I don't see a reason why we couldn't use that
> > solution - it gets rid of walking the page array, which has been fraught
> > in the past due to ARM having platforms which have holes in their
> > physical memory.
> > 
> > We could try that solution - I don't see much downside to it.  Most of
> > that information is as debug information for MM stuff anyway, and IMHO
> 
> >From an MM perspective, I can tell you that the information is close to
> useless for debugging anything. It's why I ditched it in that commit and
> AFAIK, no one has ever cared.

In that case, is there much point to show_mem()?  Is it something which
should be considered for removal?

If code serves no useful purpose anymore, we really ought to have a way
to remove it.

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