Re: ppc: RECLAIM_DISTANCE 10?
From: David Rientjes <rientjes@google.com>
Date: 2014-02-19 01:43:41
Also in:
linux-mm, lkml
On Tue, 18 Feb 2014, Nishanth Aravamudan wrote:
quoted hunk ↗ jump to hunk
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.
quoted hunk ↗ jump to hunk
@@ -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.