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Date:   Thu, 2 Aug 2018 22:13:12 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Dave Hansen <dave.hansen@intel.com>
Cc:     Reinette Chatre <reinette.chatre@intel.com>, tglx@linutronix.de,
        mingo@redhat.com, fenghua.yu@intel.com, tony.luck@intel.com,
        vikas.shivappa@linux.intel.com, gavin.hindman@intel.com,
        jithu.joseph@intel.com, hpa@zytor.com, x86@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/2] x86/intel_rdt and perf/x86: Fix lack of coordination
 with perf
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On Thu, Aug 02, 2018 at 01:06:19PM -0700, Dave Hansen wrote:
> On 08/02/2018 12:54 PM, Peter Zijlstra wrote:
> >> I totally understand not wanting to fill the tree with code hijacking
> >> the raw PMU.  Is your reaction to this really around not wanting to
> >> start down the slippery slope that ends up with lots of raw PMU "owners"?
> > That and the fact that multiple owner directly contradicts what perf set
> > out to do, provide resource arbitration for the PMU.
> > 
> > Not being able to use both perf and this resctl thing at the same time
> > is utter crap. You will not get special dispensation.
> 
> Is there something we could do in the middle, like have perf itself be
> in charge of doing all the programming, but the psuedo-locking could
> still _read_ the counters?

perf has all of that.