From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f52.google.com (mail-pa0-f52.google.com [209.85.220.52]) by kanga.kvack.org (Postfix) with ESMTP id AC00C6B0035 for ; Fri, 22 Aug 2014 18:22:03 -0400 (EDT) Received: by mail-pa0-f52.google.com with SMTP id bj1so17281756pad.25 for ; Fri, 22 Aug 2014 15:22:03 -0700 (PDT) Received: from mga02.intel.com (mga02.intel.com. [134.134.136.20]) by mx.google.com with ESMTP id ha1si42515399pbc.104.2014.08.22.15.22.02 for ; Fri, 22 Aug 2014 15:22:02 -0700 (PDT) Message-ID: <53F7C286.50800@intel.com> Date: Fri, 22 Aug 2014 15:21:58 -0700 From: Dave Hansen MIME-Version: 1.0 Subject: Re: [PATCH v2] memory-hotplug: add sysfs zones_online_to attribute References: <1407902811-4873-1-git-send-email-zhenzhang.zhang@huawei.com> <53EAE534.8030303@huawei.com> <1408138647.26567.42.camel@misato.fc.hp.com> <53F17230.5020409@huawei.com> <20140822151622.6786c1089548ea5ceb3732bf@linux-foundation.org> In-Reply-To: <20140822151622.6786c1089548ea5ceb3732bf@linux-foundation.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton , Zhang Zhen Cc: Toshi Kani , David Rientjes , isimatu.yasuaki@jp.fujitsu.com, n-horiguchi@ah.jp.nec.com, wangnan0@huawei.com, linux-kernel@vger.kernel.org, Linux MM On 08/22/2014 03:16 PM, Andrew Morton wrote: > Also, it's not really clear to me why we need this sysfs file at all. > Do people really read sysfs files, make onlining decisions and manually > type in commands? Or is this stuff all automated? If the latter then > the script can take care of all this? For example, attempt to online > the memory into the desired zone and report failure if that didn't > succeed? I guess we can just iterate over all possible zone types from userspace until we find one. Seems a bit hokey, but it would work at least until we add a new zone type and we have to teach the scripts about the new type. But that's a pretty rare event I guess. Let's hope the script writers get this right, and don't make omissions like ZONE_MOVABLE because it's not that common in practice. -- 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