On Wed, 19 Feb 2014, Nishanth Aravamudan wrote: > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > > index 3e953f07edb0..4a44bdc7a8cf 100644 > > --- a/mm/page_alloc.c > > +++ b/mm/page_alloc.c > > @@ -1855,7 +1855,7 @@ static void __paginginit init_zone_allows_reclaim(int > > nid) > > { > > int i; > > > > - for_each_online_node(i) > > + for_each_node_state(i, N_HIGH_MEMORY) > > if (node_distance(nid, i) <= RECLAIM_DISTANCE) > > node_set(i, NODE_DATA(nid)->reclaim_nodes); > > else > > @@ -4901,7 +4901,8 @@ 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); > > + if (node_state(nid, N_HIGH_MEMORY)) > > + init_zone_allows_reclaim(nid); > > I'm still new to this code, but isn't this saying that if a node has no > memory, then it shouldn't reclaim from any node? But, for a memoryless > node to ensure progress later if reclaim is necessary, it *must* reclaim > from other nodes? So wouldn't we want to set reclaim_nodes() in that > case to node_states[N_MEMORY]? >
The only time when pgdat->reclaim_nodes or zone_reclaim_mode matters is when iterating through a zonelist for page allocation and a memoryless node should never appear in a zonelist for page allocation, so this is just preventing setting zone_reclaim_mode unnecessarily because the only nodes with > RECLAIM_DISTANCE to another node are memoryless. So this patch is fine as long as it gets s/N_HIGH_MEMORY/N_MEMORY/. Acked-by: David Rientjes <rient...@google.com> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/