1 files changed, 54 insertions, 0 deletions
diff --git a/mm/showmem.c b/mm/showmem.c
new file mode 100644
index 000000000000..1103a02b2cbd
--- /dev/null
+++ b/mm/showmem.c
@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2014-2015, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/notifier.h>
+#include <linux/debugfs.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+
+ATOMIC_NOTIFIER_HEAD(show_mem_notifier);
+
+int show_mem_notifier_register(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_register(&show_mem_notifier, nb);
+}
+
+int show_mem_notifier_unregister(struct notifier_block *nb)
+{
+	return  atomic_notifier_chain_unregister(&show_mem_notifier, nb);
+}
+
+void show_mem_call_notifiers(void)
+{
+	atomic_notifier_call_chain(&show_mem_notifier, 0, NULL);
+}
+
+static int show_mem_notifier_get(void *dat, u64 *val)
+{
+	show_mem_call_notifiers();
+	*val = 0;
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(show_mem_notifier_debug_ops, show_mem_notifier_get,
+				NULL, "%llu\n");
+
+int show_mem_notifier_debugfs_register(void)
+{
+	debugfs_create_file("show_mem_notifier", 0664, NULL, NULL,
+				&show_mem_notifier_debug_ops);
+
+	return 0;
+}
+late_initcall(show_mem_notifier_debugfs_register);