From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932247AbXDIS4l (ORCPT ); Mon, 9 Apr 2007 14:56:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932263AbXDIS4k (ORCPT ); Mon, 9 Apr 2007 14:56:40 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:53912 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932247AbXDIS4k (ORCPT ); Mon, 9 Apr 2007 14:56:40 -0400 Date: Mon, 9 Apr 2007 11:56:39 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Andi Kleen cc: akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [QUICKLIST 3/4] Quicklist support for x86_64 In-Reply-To: <200704092053.05590.ak@suse.de> Message-ID: References: <20070409182509.8559.33823.sendpatchset@schroedinger.engr.sgi.com> <200704092049.34317.ak@suse.de> <200704092053.05590.ak@suse.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 9 Apr 2007, Andi Kleen wrote: > > Otherwise you will leak pages to the page allocator before the tlb flush > > occurred. > > I don't get it sorry. Can you please explain in more detail? On process teardown pages are freed via the tlb mechanism. That mechanism guarantees that TLBs for pages are flushed before they can be reused. We tie into that and put pages on quicklists. The quicklists are trimmed after the TLB flush. If a shrinker would indepedently free pages from the quicklists then this mechanism would no longer work and pages that still have a valid TLB for one process may be reused by other processes.