From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3F41FC04AB6 for ; Tue, 28 May 2019 10:43:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 10957208CB for ; Tue, 28 May 2019 10:43:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726683AbfE1KnQ (ORCPT ); Tue, 28 May 2019 06:43:16 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:54796 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726334AbfE1KnP (ORCPT ); Tue, 28 May 2019 06:43:15 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 18D7A341; Tue, 28 May 2019 03:43:15 -0700 (PDT) Received: from [10.1.196.75] (e110467-lin.cambridge.arm.com [10.1.196.75]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 652ED3F59C; Tue, 28 May 2019 03:43:13 -0700 (PDT) Subject: Re: [PATCH] arm64: mm: make CONFIG_ZONE_DMA32 configurable To: Miles Chen , Catalin Marinas , Will Deacon Cc: linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, wsd_upstream@mediatek.com References: <1558973315-19655-1-git-send-email-miles.chen@mediatek.com> From: Robin Murphy Message-ID: <814b9bd0-38de-4b8d-92b3-d663931d90bf@arm.com> Date: Tue, 28 May 2019 11:43:11 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <1558973315-19655-1-git-send-email-miles.chen@mediatek.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 27/05/2019 17:08, Miles Chen wrote: > This change makes CONFIG_ZONE_DMA32 defuly y and allows users > to overwrite it. > > For the SoCs that do not need CONFIG_ZONE_DMA32, this is the > first step to manage all available memory by a single > zone(normal zone) to reduce the overhead of multiple zones. > > The change also fixes a build error when CONFIG_NUMA=y and > CONFIG_ZONE_DMA32=n. > > arch/arm64/mm/init.c:195:17: error: use of undeclared identifier 'ZONE_DMA32' > max_zone_pfns[ZONE_DMA32] = PFN_DOWN(max_zone_dma_phys()); > > Signed-off-by: Miles Chen > --- > arch/arm64/Kconfig | 3 ++- > arch/arm64/mm/init.c | 2 ++ > 2 files changed, 4 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index 76f6e4765f49..9d20a736d1d1 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -260,7 +260,8 @@ config GENERIC_CALIBRATE_DELAY > def_bool y > > config ZONE_DMA32 > - def_bool y > + bool "Support DMA32 zone" This probably warrants an "if EMBEDDED" or "if EXPERT", since turning it off produces a kernel which won't work at all on certain systems (I've played around with this before...) > + default y > > config HAVE_GENERIC_GUP > def_bool y > diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c > index d2adffb81b5d..96829ce21f99 100644 > --- a/arch/arm64/mm/init.c > +++ b/arch/arm64/mm/init.c > @@ -191,8 +191,10 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max) > { > unsigned long max_zone_pfns[MAX_NR_ZONES] = {0}; > > +#ifdef CONFIG_ZONE_DMA32 > if (IS_ENABLED(CONFIG_ZONE_DMA32)) There's no point keeping the IS_ENABLED() check when it's entirely redundant with the #ifdefs. Robin. > max_zone_pfns[ZONE_DMA32] = PFN_DOWN(max_zone_dma_phys()); > +#endif > max_zone_pfns[ZONE_NORMAL] = max; > > free_area_init_nodes(max_zone_pfns); >