Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751848Ab0GVO5X (ORCPT ); Thu, 22 Jul 2010 10:57:23 -0400 Received: from mailout4.w1.samsung.com ([210.118.77.14]:13717 "EHLO mailout4.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750907Ab0GVO5V convert rfc822-to-8bit (ORCPT ); Thu, 22 Jul 2010 10:57:21 -0400 MIME-version: 1.0 Content-type: text/plain; charset=utf-8; format=flowed; delsp=yes Date: Thu, 22 Jul 2010 16:58:43 +0200 From: =?utf-8?B?TWljaGHFgiBOYXphcmV3aWN6?= Subject: Re: [PATCH 2/4] mm: cma: Contiguous Memory Allocator added In-reply-to: <20100722134056.GJ4737@rakim.wolfsonmicro.main> To: Mark Brown Cc: Marek Szyprowski , "'Daniel Walker'" , linux-mm@kvack.org, Pawel Osciak , "'Xiaolin Zhang'" , "'Hiremath Vaibhav'" , "'Robert Fekete'" , "'Marcus Lorentzon'" , linux-kernel@vger.kernel.org, "'Kyungmin Park'" , linux-arm-msm@vger.kernel.org Message-id: Organization: Samsung Electronics Content-transfer-encoding: 8BIT User-Agent: Opera Mail/10.60 (Linux) References: <20100721135229.GC10930@sirena.org.uk> <20100721182457.GE10930@sirena.org.uk> <20100722090602.GF10930@sirena.org.uk> <000901cb297f$e28f2b10$a7ad8130$%szyprowski@samsung.com> <20100722105203.GD4737@rakim.wolfsonmicro.main> <20100722124559.GH4737@rakim.wolfsonmicro.main> <20100722134056.GJ4737@rakim.wolfsonmicro.main> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1829 Lines: 44 On Thu, 22 Jul 2010 15:40:56 +0200, Mark Brown wrote: > On Thu, Jul 22, 2010 at 03:24:26PM +0200, Michał Nazarewicz wrote: > >> That's why command line is only intended as a way to overwrite the >> defaults which are provided by the platform. In a final product, >> configuration should be specified in platform code and not on >> command line. > > Yeah, agreed though I'm not convinced we can't do it via userspace > (initrd would give us a chance to do stuff early) or just kernel > rebuilds. If there's any other easy way of overwriting platform's default I'm happy to listen. :) >> >It sounds like apart from the way you're passing the configuration in >> >you're doing roughly what I'd suggest. I'd expect that in a lot of >> >cases the map could be satisfied from the default region so there'd be >> >no need to explicitly set one up. > >> Platform can specify something like: > >> cma_defaults("reg=20M", "*/*=reg"); > >> which would make all the drivers share 20 MiB region by default. > > Yes, exactly - probably you can even have a default region backed by > normal vmalloc() RAM which would at least be able to take a stab at > working by default. Not sure what you mean here. vmalloc() allocated buffers cannot be used with CMA since they are not contiguous in memory. -- Best regards, _ _ | Humble Liege of Serenely Enlightened Majesty of o' \,=./ `o | Computer Science, Michał "mina86" Nazarewicz (o o) +----[mina86*mina86.com]---[mina86*jabber.org]----ooO--(_)--Ooo-- -- 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/