Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266172AbUFYEuj (ORCPT ); Fri, 25 Jun 2004 00:50:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266199AbUFYEug (ORCPT ); Fri, 25 Jun 2004 00:50:36 -0400 Received: from omr3.netsolmail.com ([216.168.230.164]:37839 "EHLO omr3.netsolmail.com") by vger.kernel.org with ESMTP id S266172AbUFYEud (ORCPT ); Fri, 25 Jun 2004 00:50:33 -0400 Message-Id: <200406250449.BSB05018@ms6.netsolmail.com> Reply-To: From: "Shai Fultheim" To: "'Yasunori Goto'" , "'Dave Hansen'" Cc: "'Linux Kernel ML'" , "'Linux Hotplug Memory Support'" , "'Linux-Node-Hotplug'" , "'linux-mm'" , "'BRADLEY CHRISTIANSEN [imap]'" Subject: RE: [Lhms-devel] Re: [Lhns-devel] Merging Nonlinear and Numa style memory hotplug Date: Thu, 24 Jun 2004 21:49:42 -0700 Organization: FT Consulting MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Office Outlook, Build 11.0.5510 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2142 Thread-Index: AcRaOwzyWyhYeVqiTrW1r5RPE+W2RwANA7gQ In-Reply-To: <20040624135838.F009.YGOTO@us.fujitsu.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2622 Lines: 71 > From: linux-kernel-owner@vger.kernel.org [mailto:linux-kernel- > owner@vger.kernel.org] On Behalf Of Yasunori Goto > Sent: Thursday, June 24, 2004 15:20 > To: Dave Hansen > > > Some more comments on the first patch: > > + for(i = 0; i < numnodes; i++) { > > + if (!NODE_DATA(i)) > > + continue; > > + pgdat = NODE_DATA(i); > > + size = pgdat->node_zones[ZONE_HIGHMEM].present_pages; > > + if (!size) > > + continue; > > + hsp = pgdat->node_zones[ZONE_HIGHMEM].zone_mem_map; > > + if (hsp) > > + break; > > + } > > > > Doesn't this just find the lowest-numbered node's highmem? Are you sure > > that no NUMA systems have memory at lower physical addresses on > > higher-numbered nodes? I'm not sure that this is true. In addition I'm involved in a NUMA-related project that might have zone-normal on other nodes beside node0. I also think that in some cases it might be useful to have the code above and below in case of AMD machines that have less than 1GB per processor (or at least less than 1GB on the FIRST processor). > > + > > +#ifdef CONFIG_HOTPLUG_MEMORY_OF_NODE > > + for (nid = 0; nid < numnodes; nid++){ > > + int start, end; > > + > > + if ( !node_online(nid)) > > + continue; > > + if ( node_start_pfn[nid] >= max_low_pfn ) > > + break; > > + > > + start = node_start_pfn[nid]; > > + end = ( node_end_pfn[nid] < max_low_pfn) ? > > + node_end_pfn[nid] : max_low_pfn; > > + > > + for ( tmp = start; tmp < end; tmp++) > > + /* > > + * Only count reserved RAM pages > > + */ > > + if (page_is_ram(tmp) && > PageReserved(pfn_to_page(tmp))) > > + reservedpages++; > > + } > > +#else > > > > Again, I don't see what this loop is used for. You appear to be trying > > to detect which nodes have lowmem. Is there currently any x86 NUMA > > architecture that has lowmem on any node but node 0? > > > > > > > > -- Dave As noted above, this is possible, the cost of this code is not much, so I would keep it in. --shai - 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/