From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Hocko Date: Wed, 16 Jan 2013 14:14:36 +0000 Subject: Re: [PATCH v3 1/2] memory-hotplug: introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_ Message-Id: <20130116141436.GE343@dhcp22.suse.cz> List-Id: References: <1358324059-9608-1-git-send-email-linfeng@cn.fujitsu.com> <1358324059-9608-2-git-send-email-linfeng@cn.fujitsu.com> In-Reply-To: <1358324059-9608-2-git-send-email-linfeng@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Lin Feng Cc: akpm@linux-foundation.org, linux-mm@kvack.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, jbeulich@suse.com, dhowells@redhat.com, wency@cn.fujitsu.com, isimatu.yasuaki@jp.fujitsu.com, paul.gortmaker@windriver.com, laijs@cn.fujitsu.com, kamezawa.hiroyu@jp.fujitsu.com, mel@csn.ul.ie, minchan@kernel.org, aquini@redhat.com, jiang.liu@huawei.com, tony.luck@intel.com, fenghua.yu@intel.com, benh@kernel.crashing.org, paulus@samba.org, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, davem@davemloft.net, michael@ellerman.id.au, gerald.schaefer@de.ibm.com, gregkh@linuxfoundation.org, x86@kernel.org, linux390@de.ibm.com, linux-ia64@vger.kernel.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, tangchen@cn.fujitsu.com On Wed 16-01-13 16:14:18, Lin Feng wrote: [...] > diff --git a/mm/Kconfig b/mm/Kconfig > index 278e3ab..f8c5799 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -162,10 +162,18 @@ config MOVABLE_NODE > Say Y here if you want to hotplug a whole node. > Say N here if you want kernel to use memory on all nodes evenly. > > +# > +# Only be set on architectures that have completely implemented memory hotplug > +# feature. If you are not sure, don't touch it. > +# > +config HAVE_BOOTMEM_INFO_NODE > + def_bool n > + > # eventually, we can have this option just 'select SPARSEMEM' > config MEMORY_HOTPLUG > bool "Allow for memory hot-add" > select MEMORY_ISOLATION > + select HAVE_BOOTMEM_INFO_NODE if X86_64 > depends on SPARSEMEM || X86_64_ACPI_NUMA > depends on HOTPLUG && ARCH_ENABLE_MEMORY_HOTPLUG > depends on (IA64 || X86 || PPC_BOOK3S_64 || SUPERH || S390) I am still not sure I understand the relation to MEMORY_HOTREMOVE. Is register_page_bootmem_info_node required/helpful even if !CONFIG_MEMORY_HOTREMOVE? Also, now that I am thinking about that more, maybe it would be cleaner to put the select into arch/x86/Kconfig and do it same as ARCH_ENABLE_MEMORY_{HOTPLUG,HOTREMOVE} (and name it ARCH_HAVE_BOOTMEM_INFO_NODE). -- Michal Hocko SUSE Labs