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Date: Wed, 4 Nov 2015 16:28:04 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Luiz Capitulino <lcapitulino@redhat.com>
cc: Fenghua Yu <fenghua.yu@intel.com>, H Peter Anvin <hpa@zytor.com>,
        Ingo Molnar <mingo@redhat.com>, Peter Zijlstra <peterz@infradead.org>,
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        Vikas Shivappa <vikas.shivappa@linux.intel.com>,
        Marcelo Tosatti <mtosatti@redhat.com>, tj@kernel.org, riel@redhat.com
Subject: Re: [PATCH V15 00/11] x86: Intel Cache Allocation Technology
 Support
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On Wed, 4 Nov 2015, Luiz Capitulino wrote:
> On Wed, 4 Nov 2015 15:57:41 +0100 (CET)
> Thomas Gleixner <tglx@linutronix.de> wrote:
> 
> > On Wed, 4 Nov 2015, Luiz Capitulino wrote:
> > 
> > > On Thu,  1 Oct 2015 23:09:34 -0700
> > > Fenghua Yu <fenghua.yu@intel.com> wrote:
> > > 
> > > > This series has some preparatory patches and Intel cache allocation
> > > > support.
> > > 
> > > Ping? What's the status of this series?
> > 
> > We still need to agree on the user space interface which is the
> > hardest part of it....
> 
> My understanding is that two interfaces have been proposed: the cgroups
> one and an API based on syscalls or ioctls.
> 
> Are those proposals mutual exclusive? What about having the cgroups one
> merged IFF it's useful, and having the syscall API later if really
> needed?
> 
> I don't want to make the wrong decision, but the cgroups interface is
> here. Holding it while we discuss a perfect interface that doesn't
> even exist will just do a bad service for users.

Well, no. We do not just introduce a random user space ABI simply
because we have to support it forever.

Thanks,

	tglx