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Date: Fri, 29 Apr 2016 11:18:59 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: David Carrillo-Cisneros <davidcc@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Ingo Molnar <mingo@redhat.com>,
        Vikas Shivappa <vikas.shivappa@linux.intel.com>,
        Matt Fleming <matt.fleming@intel.com>, Tony Luck <tony.luck@intel.com>,
        Stephane Eranian <eranian@google.com>, Paul Turner <pjt@google.com>,
        x86@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 08/32] perf/x86/intel/cqm: prepare for next patches
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On Thu, Apr 28, 2016 at 09:43:14PM -0700, David Carrillo-Cisneros wrote:
> Move code around, delete unnecesary code and do some renaming in
> in order to increase readibility of next patches. Create cqm.h file.

*sigh*, this is a royal pain in the backside to review.

Please just completely wipe the old driver in patch 1, preserve
_nothing_.

Then start adding bits back, in gradual coherent pieces. Like that msr
write optimization you need new hooks for, that should be a patch doing
just that, optimize, it should not introduce new functionality etc..

This piecewise removal of small bits makes it entirely hard to see the
complete picture of what is introduced here.