From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx106.postini.com [74.125.245.106]) by kanga.kvack.org (Postfix) with SMTP id 2038C6B0032 for ; Mon, 9 Sep 2013 19:58:19 -0400 (EDT) Received: from /spool/local by e23smtp09.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 10 Sep 2013 20:51:55 +1000 Received: from d23relay03.au.ibm.com (d23relay03.au.ibm.com [9.190.235.21]) by d23dlp03.au.ibm.com (Postfix) with ESMTP id 4423C3578054 for ; Tue, 10 Sep 2013 09:58:12 +1000 (EST) Received: from d23av04.au.ibm.com (d23av04.au.ibm.com [9.190.235.139]) by d23relay03.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r89Nvqot6488398 for ; Tue, 10 Sep 2013 09:58:01 +1000 Received: from d23av04.au.ibm.com (loopback [127.0.0.1]) by d23av04.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r89Nw2Ac023119 for ; Tue, 10 Sep 2013 09:58:03 +1000 Date: Tue, 10 Sep 2013 07:58:00 +0800 From: Wanpeng Li Subject: Re: [PATCH 00/11] x86, memblock: Allocate memory near kernel image before SRAT parsed. Message-ID: <20130909235800.GA30121@hacker.(null)> Reply-To: Wanpeng Li References: <1377596268-31552-1-git-send-email-tangchen@cn.fujitsu.com> <20130904192215.GG26609@mtj.dyndns.org> <52299935.0302450a.26c9.ffffb240SMTPIN_ADDED_BROKEN@mx.google.com> <20130906151526.GA22423@mtj.dyndns.org> <522db781.22ab440a.41b1.ffffd825SMTPIN_ADDED_BROKEN@mx.google.com> <20130909135815.GB25434@htj.dyndns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130909135815.GB25434@htj.dyndns.org> Sender: owner-linux-mm@kvack.org List-ID: To: Tejun Heo Cc: rjw@sisk.pl, lenb@kernel.org, tglx@linutronix.de, mingo@elte.hu, hpa@zytor.com, akpm@linux-foundation.org, trenn@suse.de, yinghai@kernel.org, jiang.liu@huawei.com, wency@cn.fujitsu.com, laijs@cn.fujitsu.com, isimatu.yasuaki@jp.fujitsu.com, izumi.taku@jp.fujitsu.com, mgorman@suse.de, minchan@kernel.org, mina86@mina86.com, gong.chen@linux.intel.com, vasilis.liaskovitis@profitbricks.com, lwoodman@redhat.com, riel@redhat.com, jweiner@redhat.com, prarit@redhat.com, zhangyanfei@cn.fujitsu.com, x86@kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-acpi@vger.kernel.org Hi Tejun, On Mon, Sep 09, 2013 at 09:58:15AM -0400, Tejun Heo wrote: >Hello, > >On Mon, Sep 09, 2013 at 07:56:34PM +0800, Wanpeng Li wrote: >> If allocate from low to high as what this patchset done will occupy the >> precious memory you mentioned? > >Yeah, and that'd be the reason why this behavior is dependent on a >kernel option. That said, allocating some megs on top of kernel isn't >a big deal. The wretched ISA DMA is mostly gone now and some megs >isn't gonna hurt 32bit DMAs in any noticeable way. I wouldn't be too >surprised if nobody notices after switching the default behavior to >allocate early mem close to kernel. Maybe the only case which might >be impacted is 32bit highmem configs, but they're messed up no matter >what anyway and even they shouldn't be affected noticeably if large >mapping is in use. ISA DMA is still survive for 32bit highmem configs. In my desktop: c1000000 T _text => 16MB c1d09000 B _end => 29MB This patchset will alloc after 29MB. ;-) Regards, Wanpeng Li > >Thanks. > >-- >tejun -- 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/ . Don't email: email@kvack.org