From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 30 Sep 2008 17:06:08 +0900 From: Yasunori Goto Subject: Re: [PATCH] mm: show node to memory section relationship with symlinks in sysfs In-Reply-To: <20080929200509.GC21255@us.ibm.com> References: <20080929200509.GC21255@us.ibm.com> Message-Id: <20080930163324.44A7.E1E9C6FF@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Gary Hade Cc: linux-mm@kvack.org, Andrew Morton , Badari Pulavarty , Mel Gorman , Chris McDermott , linux-kernel@vger.kernel.org, Ingo Molnar , Greg KH , Dave Hansen , Nish Aravamudan List-ID: > +#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE > +int register_mem_sect_under_node(struct memory_block *mem_blk) : I think this patch is convenience even when memory hotplug is disabled. CONFIG_SPARSEMEM seems better than CONFIG_MEMORY_HOTPLUG_SPARSE. > +int register_mem_sect_under_node(struct memory_block *mem_blk) > +{ > + unsigned int nid; > + > + if (!mem_blk) > + return -EFAULT; > + nid = section_nr_to_nid(mem_blk->phys_index); (snip) > +#define section_nr_to_nid(section_nr) pfn_to_nid(section_nr_to_pfn(section_nr)) > #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ If the first page of the section is not valid, then this section_nr_to_nid() doesn't return correct value. I tested this patch. In my box, the start_pfn of node 1 is 1200400, but section_nr_to_pfn(mem_blk->phys_index) returns 1200000. As a result, the section is linked to node 0. Bye. -- Yasunori Goto -- 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