From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760047AbXLLTPq (ORCPT ); Wed, 12 Dec 2007 14:15:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752228AbXLLTP1 (ORCPT ); Wed, 12 Dec 2007 14:15:27 -0500 Received: from gw.goop.org ([64.81.55.164]:54021 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751089AbXLLTPZ (ORCPT ); Wed, 12 Dec 2007 14:15:25 -0500 Message-ID: <47603321.4030700@goop.org> Date: Wed, 12 Dec 2007 11:14:41 -0800 From: Jeremy Fitzhardinge User-Agent: Thunderbird 2.0.0.9 (X11/20071115) MIME-Version: 1.0 To: Christoph Lameter , Suresh Siddha CC: Linux Kernel Mailing List , Ingo Molnar , Andi Kleen , Tony Luck , Asit Mallick , Andrew Morton Subject: What was the problem with quicklists and x86-64? X-Enigmail-Version: 0.95.5 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I'm looking at unifying the various pgalloc+pgd_lists mechanisms between 32-bit (PAE and non-PAE) and 64-bit, so I'm trying to understand why these differences exist in the first place. Change da8f153e51290e7438ba7da66234a864e5d3e1c1 reverted the use of quicklists for allocating pagetables, because of concerns about ordering with respect to tlb flushes. Some questions about this: 1. What's the difference between quicklists and normal page allocation with respect to tlb flushing? 2. Why doesn't this also affect i386's use of quicklists? 3. Is there some way to resolve this tlb interaction so that quicklists can be used? 4. Failing that, what's the cost of reverting i386's use of quicklists too? Thanks, J