Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267404AbUJGPlm (ORCPT ); Thu, 7 Oct 2004 11:41:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267397AbUJGPkn (ORCPT ); Thu, 7 Oct 2004 11:40:43 -0400 Received: from e5.ny.us.ibm.com ([32.97.182.105]:52702 "EHLO e5.ny.us.ibm.com") by vger.kernel.org with ESMTP id S267396AbUJGPkc (ORCPT ); Thu, 7 Oct 2004 11:40:32 -0400 Subject: Re: [PATCH] no buddy bitmap patch : intro and includes [0/2] From: Dave Hansen To: Matthew E Tolentino Cc: "Martin J. Bligh" , Hiroyuki KAMEZAWA , Linux Kernel ML , linux-mm , lhms , Andrew Morton , William Lee Irwin III , "Luck, Tony" , Hirokazu Takahashi In-Reply-To: References: Content-Type: text/plain Message-Id: <1097163578.3625.43.camel@localhost> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 Date: Thu, 07 Oct 2004 08:39:38 -0700 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1096 Lines: 25 On Thu, 2004-10-07 at 08:03, Tolentino, Matthew E wrote: > >> Followings are patches for removing bitmaps from buddy=20 > >allocator, against 2.6.9-rc3. > >> I think this version is much clearer than ones I posted a month ago. > >... > >> If there is unclear point, please tell me. > > > >What was the purpose behind this, again? Sorry, has been too long since > >I last looked. > > For one, it avoids the otherwise requisite resizing of the bitmaps=20 > during memory hotplug operations... It also simplifies the nonlinear implementation. The whole reason we had the lpfn (Linear) stuff was so that the bitmaps could represent a sparse physical address space in a much more linear fashion. With no bitmaps, this isn't an issue, and gets rid of a lot of code, and a *huge* source of bugs where lpfns and pfns are confused for each other. -- Dave - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/