[PATCH] Replace highest_possible_node_id() with nr_node_ids
highest_possible_node_id() is currently used to calculate the last possible
node idso that the network subsystem can figure out how to size per node
arrays.
I think having the ability to determine the maximum amount of nodes in a
system at runtime is useful but then we should name this entry
correspondingly, it should return the number of node_ids, and the the value
needs to be setup only once on bootup. The node_possible_map does not
change after bootup.
This patch introduces nr_node_ids and replaces the use of
highest_possible_node_id(). nr_node_ids is calculated on bootup when the
page allocators pagesets are initialized.
[deweerdt@free.fr: fix oops]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d461b23..f66538b 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -664,6 +664,26 @@
return i;
}
+#if MAX_NUMNODES > 1
+int nr_node_ids __read_mostly;
+EXPORT_SYMBOL(nr_node_ids);
+
+/*
+ * Figure out the number of possible node ids.
+ */
+static void __init setup_nr_node_ids(void)
+{
+ unsigned int node;
+ unsigned int highest = 0;
+
+ for_each_node_mask(node, node_possible_map)
+ highest = node;
+ nr_node_ids = highest + 1;
+}
+#else
+static void __init setup_nr_node_ids(void) {}
+#endif
+
#ifdef CONFIG_NUMA
/*
* Called from the slab reaper to drain pagesets on a particular node that
@@ -3169,6 +3189,7 @@
min_free_kbytes = 65536;
setup_per_zone_pages_min();
setup_per_zone_lowmem_reserve();
+ setup_nr_node_ids();
return 0;
}
module_init(init_per_zone_pages_min)
@@ -3370,18 +3391,4 @@
EXPORT_SYMBOL(page_to_pfn);
#endif /* CONFIG_OUT_OF_LINE_PFN_TO_PAGE */
-#if MAX_NUMNODES > 1
-/*
- * Find the highest possible node id.
- */
-int highest_possible_node_id(void)
-{
- unsigned int node;
- unsigned int highest = 0;
- for_each_node_mask(node, node_possible_map)
- highest = node;
- return highest;
-}
-EXPORT_SYMBOL(highest_possible_node_id);
-#endif
