From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f42.google.com (mail-pa0-f42.google.com [209.85.220.42]) by kanga.kvack.org (Postfix) with ESMTP id 700D46B0031 for ; Tue, 18 Feb 2014 20:43:41 -0500 (EST) Received: by mail-pa0-f42.google.com with SMTP id kl14so17536235pab.15 for ; Tue, 18 Feb 2014 17:43:41 -0800 (PST) Received: from mail-pb0-x235.google.com (mail-pb0-x235.google.com [2607:f8b0:400e:c01::235]) by mx.google.com with ESMTPS id eb3si20060483pbc.326.2014.02.18.17.43.40 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 18 Feb 2014 17:43:40 -0800 (PST) Received: by mail-pb0-f53.google.com with SMTP id md12so17533259pbc.12 for ; Tue, 18 Feb 2014 17:43:40 -0800 (PST) Date: Tue, 18 Feb 2014 17:43:38 -0800 (PST) From: David Rientjes Subject: Re: ppc: RECLAIM_DISTANCE 10? In-Reply-To: <20140218235800.GC10844@linux.vnet.ibm.com> Message-ID: References: <20140218090658.GA28130@dhcp22.suse.cz> <20140218233404.GB10844@linux.vnet.ibm.com> <20140218235800.GC10844@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Nishanth Aravamudan Cc: Michal Hocko , linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, Anton Blanchard , LKML On Tue, 18 Feb 2014, Nishanth Aravamudan wrote: > How about the following? > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 5de4337..1a0eced 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -1854,7 +1854,8 @@ static void __paginginit init_zone_allows_reclaim(int nid) > int i; > > for_each_online_node(i) > - if (node_distance(nid, i) <= RECLAIM_DISTANCE) > + if (node_distance(nid, i) <= RECLAIM_DISTANCE || > + !NODE_DATA(i)->node_present_pages) > node_set(i, NODE_DATA(nid)->reclaim_nodes); > else > zone_reclaim_mode = 1; [ I changed the above from NODE_DATA(nid) -> NODE_DATA(i) as you caught so we're looking at the right code. ] That can't be right, it would allow reclaiming from a memoryless node. I think what you want is for_each_online_node(i) { if (!node_present_pages(i)) continue; if (node_distance(nid, i) <= RECLAIM_DISTANCE) { node_set(i, NODE_DATA(nid)->reclaim_nodes); continue; } /* Always try to reclaim locally */ zone_reclaim_mode = 1; } but we really should be able to do for_each_node_state(i, N_MEMORY) here and memoryless nodes should already be excluded from that mask. > @@ -4901,13 +4902,13 @@ void __paginginit free_area_init_node(int nid, unsigned long *zones_size, > > pgdat->node_id = nid; > pgdat->node_start_pfn = node_start_pfn; > - init_zone_allows_reclaim(nid); > #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP > get_pfn_range_for_nid(nid, &start_pfn, &end_pfn); > #endif > calculate_node_totalpages(pgdat, start_pfn, end_pfn, > zones_size, zholes_size); > > + init_zone_allows_reclaim(nid); > alloc_node_mem_map(pgdat); > #ifdef CONFIG_FLAT_NODE_MEM_MAP > printk(KERN_DEBUG "free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n", > > I think it's safe to move init_zone_allows_reclaim, because I don't > think any allocates are occurring here that could cause us to reclaim > anyways, right? Moving it allows us to safely reference > node_present_pages. > Yeah, this is fine. -- 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