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 S1754670AbdLFJhP (ORCPT <rfc822;w@1wt.eu>);
        Wed, 6 Dec 2017 04:37:15 -0500
Received: from bombadil.infradead.org ([65.50.211.133]:38695 "EHLO
        bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1754619AbdLFJhL (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Wed, 6 Dec 2017 04:37:11 -0500
Date: Wed, 6 Dec 2017 10:37:05 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Dave Hansen <dave.hansen@intel.com>
Cc: the arch/x86 maintainers <x86@kernel.org>,
        Andy Lutomirski <luto@kernel.org>, LKML <linux-kernel@vger.kernel.org>,
        Linux-MM <linux-mm@kvack.org>, "Kleen, Andi" <andi.kleen@intel.com>,
        "Chen, Tim C" <tim.c.chen@intel.com>,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: x86 TLB flushing: INVPCID vs. deferred CR3 write
Message-ID: <20171206093705.y74zuyexf44sl6n4@hirez.programming.kicks-ass.net>
References: <3062e486-3539-8a1f-5724-16199420be71@intel.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <3062e486-3539-8a1f-5724-16199420be71@intel.com>
User-Agent: NeoMutt/20170609 (1.8.3)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Tue, Dec 05, 2017 at 05:27:31PM -0800, Dave Hansen wrote:
> tl;dr: Kernels with pagetable isolation using INVPCID compile kernels
> 0.58% faster than using the deferred CR3 write.  This tends to say that
> we should leave things as-is and keep using INVPCID, but it's far from
> definitive.

Much appreciated, thanks Dave!