From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from d01relay02.pok.ibm.com (d01relay02.pok.ibm.com [9.56.227.234]) by e2.ny.us.ibm.com (8.12.11/8.12.11) with ESMTP id k2LI1qtK000638 for ; Tue, 21 Mar 2006 13:01:52 -0500 Received: from d01av02.pok.ibm.com (d01av02.pok.ibm.com [9.56.224.216]) by d01relay02.pok.ibm.com (8.12.10/NCO/VER6.8) with ESMTP id k2LI1erQ246416 for ; Tue, 21 Mar 2006 13:01:42 -0500 Received: from d01av02.pok.ibm.com (loopback [127.0.0.1]) by d01av02.pok.ibm.com (8.12.11/8.13.3) with ESMTP id k2LI1enT009830 for ; Tue, 21 Mar 2006 13:01:40 -0500 Subject: Re: [PATCH: 002/017]Memory hotplug for new nodes v.4.(change name old add_memory() to arch_add_memory()) From: Dave Hansen In-Reply-To: <20060318102653.57c6a2af.kamezawa.hiroyu@jp.fujitsu.com> References: <20060317162757.C63B.Y-GOTO@jp.fujitsu.com> <1142615538.10906.67.camel@localhost.localdomain> <20060318102653.57c6a2af.kamezawa.hiroyu@jp.fujitsu.com> Content-Type: text/plain Date: Tue, 21 Mar 2006 10:00:12 -0800 Message-Id: <1142964013.10906.158.camel@localhost.localdomain> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: KAMEZAWA Hiroyuki Cc: y-goto@jp.fujitsu.com, akpm@osdl.org, tony.luck@intel.com, ak@suse.de, linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org, linux-mm@kvack.org List-ID: On Sat, 2006-03-18 at 10:26 +0900, KAMEZAWA Hiroyuki wrote: > If *determine node* function is moved to arch specific parts, > memory hot add need more and more codes to determine paddr -> nid in arch > specific codes. Then, we have to add new paddr->nid function even if new nid is > passed by firmware. We *lose* useful information of nid from firmware if > add_memory() has just 2 args, (start, end). What I'm saying is that I'd like add_memory() to be just that, for adding memory. At some point in the process, you need to export the NUMA node layout to the rest of the system, to say which pages go in which node. I'm just saying that you should do that _before_ add_memory(). add_memory() should support adding memory to more than one node. If any hypervisor or hardware happens to have memory added in one contiguous chunk, it can not simply call add_memory(). _That_ firmware would be forced to do the NUMA parsing and figure out how many times to call add_memory(). Let me reiterate: the process of telling the system which pages are in which node should be separate from telling the system that there *are* currently pages there now. -- Dave -- 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