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Date: Thu, 26 Jun 2014 16:20:14 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: "Luis R. Rodriguez" <mcgrof@suse.com>
Cc: "Luis R. Rodriguez" <mcgrof@do-not-panic.com>, gregkh@linuxfoundation.org,
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        Kees Cook <keescook@chromium.org>, Davidlohr Bueso <davidlohr@hp.com>,
        Chris Metcalf <cmetcalf@tilera.com>
Subject: Re: [PATCH v8 4/4] printk: allow increasing the ring buffer
 depending on the number of CPUs
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On Fri, 27 Jun 2014 01:16:30 +0200 "Luis R. Rodriguez" <mcgrof@suse.com> wrote:

> > > Another note --  since this option depends on SMP and !BASE_SMALL technically 
> > > num_possible_cpus() won't ever return something smaller than or equal to 1
> > > but because of the default values chosen the -1 on the compuation does affect
> > > whether or not this will trigger on > 64 CPUs or >= 64 CPUs, keeping the
> > > -1 means we require > 64 CPUs.
> > 
> > hm, that sounds like more complexity.
> > 
> > > This all can be changed however we like but the language and explained logic
> > > would just need to be changed.
> > 
> > Let's start out simple.  What's wrong with doing
> > 
> > 	log buf len = max(__LOG_BUF_LEN, nr_possible_cpus * per-cpu log buf len)
> 
> Sure, you already took in the patch series though so how would you like to
> handle a respin, you just drop the last patch and we respin it?

A fresh patch would suit.  That's if you think it is a reasonable 
approach - you've thought about this stuff more than I have!