Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754186AbbFKKoJ (ORCPT ); Thu, 11 Jun 2015 06:44:09 -0400 Received: from cn.fujitsu.com ([59.151.112.132]:17147 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751678AbbFKKoA (ORCPT ); Thu, 11 Jun 2015 06:44:00 -0400 X-IronPort-AV: E=Sophos;i="5.01,1,1399996800"; d="scan'208";a="96855046" Message-ID: <557965D1.7020009@cn.fujitsu.com> Date: Thu, 11 Jun 2015 18:41:21 +0800 From: Zhu Guihua User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.4.0 MIME-Version: 1.0 To: Andrew Morton CC: , , , , , , , Subject: Re: [PATCH] mm/memory hotplug: print the last vmemmap region at the end of hot add memory References: <1433745881-7179-1-git-send-email-zhugh.fnst@cn.fujitsu.com> <20150608163053.c481d9a5057513130f760910@linux-foundation.org> <55766068.9090809@cn.fujitsu.com> <20150609132908.c5a9d2c9714bd7a8f33ffde8@linux-foundation.org> In-Reply-To: <20150609132908.c5a9d2c9714bd7a8f33ffde8@linux-foundation.org> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.167.226.252] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1581 Lines: 48 On 06/10/2015 04:29 AM, Andrew Morton wrote: > On Tue, 9 Jun 2015 11:41:28 +0800 Zhu Guihua wrote: > >>>> --- a/mm/memory_hotplug.c >>>> +++ b/mm/memory_hotplug.c >>>> @@ -513,6 +513,7 @@ int __ref __add_pages(int nid, struct zone *zone, unsigned long phys_start_pfn, >>>> break; >>>> err = 0; >>>> } >>>> + vmemmap_populate_print_last(); >>>> >>>> return err; >>>> } >>> vmemmap_populate_print_last() is only available on x86_64, when >>> CONFIG_SPARSEMEM_VMEMMAP=y. Are you sure this won't break builds? >> I tried this on i386 and on x86_64 when CONFIG_SPARSEMEM_VMEMMAP=n , >> it builds ok. > With powerpc: > > akpm3:/usr/src/25> make allmodconfig > akpm3:/usr/src/25> make mm/memory_hotplug.o > akpm3:/usr/src/25> nm mm/memory_hotplug.o | grep vmemmap_populate_print_last > U .vmemmap_populate_print_last > akpm3:/usr/src/25> grep -r vmemmap_populate_print_last arch/powerpc > akpm3:/usr/src/25> > > So I think that's going to break. > > I expect ia64 will break also, but I didn't investigate. > . > There is void __weak __meminit vmemmap_populate_print last(void) in /mm/sparse.c, so I think this won't break builds. And I found the function was invoked in void __init sparse_init(void) without CONFIG_SPARSEMEM_VMEMMAP=y. I also tried this on arm, it builds ok too. -- 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/