include/linux/nodemask.h: create next_node_in() helper
Lots of code does
node = next_node(node, XXX);
if (node == MAX_NUMNODES)
node = first_node(XXX);
so create next_node_in() to do this and use it in various places.
[mhocko@suse.com: use next_node_in() helper]
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Hui Zhu <zhuhui@xiaomi.com>
Cc: Wang Xiaoqiang <wangxq10@lzu.edu.cn>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/lib/nodemask.c b/lib/nodemask.c
new file mode 100644
index 0000000..e42a5bf4
--- /dev/null
+++ b/lib/nodemask.c
@@ -0,0 +1,30 @@
+#include <linux/nodemask.h>
+#include <linux/module.h>
+#include <linux/random.h>
+
+int __next_node_in(int node, const nodemask_t *srcp)
+{
+ int ret = __next_node(node, srcp);
+
+ if (ret == MAX_NUMNODES)
+ ret = __first_node(srcp);
+ return ret;
+}
+EXPORT_SYMBOL(__next_node_in);
+
+#ifdef CONFIG_NUMA
+/*
+ * Return the bit number of a random bit set in the nodemask.
+ * (returns NUMA_NO_NODE if nodemask is empty)
+ */
+int node_random(const nodemask_t *maskp)
+{
+ int w, bit = NUMA_NO_NODE;
+
+ w = nodes_weight(*maskp);
+ if (w)
+ bit = bitmap_ord_to_pos(maskp->bits,
+ get_random_int() % w, MAX_NUMNODES);
+ return bit;
+}
+#endif