From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753152AbaJQN2S (ORCPT ); Fri, 17 Oct 2014 09:28:18 -0400 Received: from foss-mx-na.foss.arm.com ([217.140.108.86]:45448 "EHLO foss-mx-na.foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751816AbaJQN2Q (ORCPT ); Fri, 17 Oct 2014 09:28:16 -0400 Date: Fri, 17 Oct 2014 14:28:02 +0100 From: Catalin Marinas To: Yifan Zhang Cc: Will Deacon , Mark Rutland , "lauraa@codeaurora.org" , "ganapatrao.kulkarni@caviumnetworks.com" , "robh@kernel.org" , "leif.lindholm@linaro.org" , "Yalin.Wang@sonymobile.com" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , Yifan Zhang Subject: Re: [PATCH v2] arm64: mm: use macro instead of if judgement of ZONE_DMA Message-ID: <20141017132801.GH10873@e104818-lin.cambridge.arm.com> References: <20141016171012.GE5252@e104818-lin.cambridge.arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 17, 2014 at 04:08:43AM +0100, Yifan Zhang wrote: > I found In current arm64 code, there is no normal zone, only DMA zone. > > Number of blocks type Unmovable Reclaimable Movable > Reserve CMA Isolate > > Node 0, zone DMA 142 12 69 > 1 28 0 > > When zone_sizes_init, zone_size[ZONE_NORMAL] is initialized to 0. (it > is 3.10, I didn't try the latest code base) [...] > Is this ZONE_DMA cover full memory and ZONE_NORMAL = 0 strategy on > purpose ? We will not use ZONE_NORMAL on arm64 ? The normal zone is still there, only that it doesn't have any pages. The page allocator falls back to the DMA zone, so you would not see any problems with normal page allocation. Are you trying to solve anything (performance?) or just what the kernel shows as part of the normal zone? -- Catalin