From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta12.messagelabs.com (mail6.bemta12.messagelabs.com [216.82.250.247]) by kanga.kvack.org (Postfix) with ESMTP id 8AD226B0012 for ; Tue, 14 Jun 2011 14:30:40 -0400 (EDT) From: Arnd Bergmann Subject: Re: [PATCH 08/10] mm: cma: Contiguous Memory Allocator added Date: Tue, 14 Jun 2011 20:30:07 +0200 References: <1307699698-29369-1-git-send-email-m.szyprowski@samsung.com> <201106141803.00876.arnd@arndb.de> In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <201106142030.07549.arnd@arndb.de> Sender: owner-linux-mm@kvack.org List-ID: To: Michal Nazarewicz Cc: Marek Szyprowski , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org, linux-mm@kvack.org, linaro-mm-sig@lists.linaro.org, 'Kyungmin Park' , 'Andrew Morton' , 'KAMEZAWA Hiroyuki' , 'Ankita Garg' , 'Daniel Walker' , 'Mel Gorman' , 'Jesse Barker' On Tuesday 14 June 2011 18:58:35 Michal Nazarewicz wrote: > On Tue, 14 Jun 2011 18:03:00 +0200, Arnd Bergmann wrote: > > For all I know, that is something that is only true for a few very > > special Samsung devices, > > Maybe. I'm just answering your question. :) > > Ah yes, I forgot that separate regions for different purposes could > decrease fragmentation. That is indeed a good point, but having a good allocator algorithm could also solve this. I don't know too much about these allocation algorithms, but there are probably multiple working approaches to this. > > I would suggest going forward without having multiple regions: > > Is having support for multiple regions a bad thing? Frankly, > removing this support will change code from reading context passed > as argument to code reading context from global variable. Nothing > is gained; functionality is lost. What is bad IMHO is making them the default, which forces the board code to care about memory management details. I would much prefer to have contiguous allocation parameters tuned automatically to just work on most boards before we add ways to do board-specific hacks. Arnd -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org