From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1751526AbdKHIqA (ORCPT <rfc822;w@1wt.eu>);
        Wed, 8 Nov 2017 03:46:00 -0500
Received: from smtp-fw-9102.amazon.com ([207.171.184.29]:7828 "EHLO
        smtp-fw-9102.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1750752AbdKHIp5 (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Wed, 8 Nov 2017 03:45:57 -0500
X-IronPort-AV: E=Sophos;i="5.44,363,1505779200"; 
   d="scan'208";a="571933577"
Date: Wed, 8 Nov 2017 00:45:47 -0800
From: Eduardo Valentin <eduval@amazon.com>
To: Paolo Bonzini <pbonzini@redhat.com>
CC: Eduardo Valentin <eduval@amazon.com>, <rkrcmar@redhat.com>,
        Matt Wilson <msw@amazon.com>, Jonathan Corbet <corbet@lwn.net>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>, <x86@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Waiman Long <longman@redhat.com>, <kvm@vger.kernel.org>,
        <linux-doc@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        "Jan H . Schoenherr" <jschoenh@amazon.de>,
        Anthony Liguori <aliguori@amazon.com>
Subject: Re: [PATCHv3 1/1] locking/qspinlock/x86: Avoid test-and-set when
 PV_DEDICATED is set
Message-ID: <20171108084547.GC13350@u40b0340c692b58f6553c.ant.amazon.com>
References: <1509999980-10828-1-git-send-email-eduval@amazon.com>
 <593c8cc3-f532-1868-c80f-7ef2511c7e15@redhat.com>
 <20171107123922.GA6336@u40b0340c692b58f6553c.ant.amazon.com>
 <e56f1b14-2c11-de8a-8042-6de97a2fccb7@redhat.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Disposition: inline
In-Reply-To: <e56f1b14-2c11-de8a-8042-6de97a2fccb7@redhat.com>
User-Agent: Mutt/1.5.24 (2015-08-30)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Paolo,

On Tue, Nov 07, 2017 at 01:43:15PM +0100, Paolo Bonzini wrote:
> On 07/11/2017 13:39, Eduardo Valentin wrote:
> >> is this still needed after Waiman's patch to adaptively switch between
> >> tas and pvqspinlock?
> > Can you please point me to it ? Is it already in tip/master?
> > 
> 
> No, he just posted it:
> 
> https://marc.info/?l=linux-kernel&m=150972337909996&w=2

OK, Thanks. I've reviewed his V2. I think the patch to have PV_DEDICATED is still interesting to have,
for the case the guest is in autoselect mode and honors what the host gives as hints.

> 
> Paolo

-- 
All the best,
Eduardo Valentin