1 files changed, 72 insertions, 0 deletions

diff --git a/kernel/time/timekeeping_debug.c b/kernel/time/timekeeping_debug.c
new file mode 100644
index 000000000000..802433a4f5eb
--- /dev/null
+++ b/kernel/time/timekeeping_debug.c
@@ -0,0 +1,72 @@
+/*
+ * debugfs file to track time spent in suspend
+ *
+ * Copyright (c) 2011, Google, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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/debugfs.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/seq_file.h>
+#include <linux/time.h>
+
+static unsigned int sleep_time_bin[32] = {0};
+
+static int tk_debug_show_sleep_time(struct seq_file *s, void *data)
+{
+        unsigned int bin;
+        seq_puts(s, "      time (secs)        count\n");
+        seq_puts(s, "------------------------------\n");
+        for (bin = 0; bin < 32; bin++) {
+                if (sleep_time_bin[bin] == 0)
+                        continue;
+                seq_printf(s, "%10u - %-10u %4u\n",
+                        bin ? 1 << (bin - 1) : 0, 1 << bin,
+                                sleep_time_bin[bin]);
+        }
+        return 0;
+}
+
+static int tk_debug_sleep_time_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, tk_debug_show_sleep_time, NULL);
+}
+
+static const struct file_operations tk_debug_sleep_time_fops = {
+        .open           = tk_debug_sleep_time_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+};
+
+static int __init tk_debug_sleep_time_init(void)
+{
+        struct dentry *d;
+
+        d = debugfs_create_file("sleep_time", 0444, NULL, NULL,
+                &tk_debug_sleep_time_fops);
+        if (!d) {
+                pr_err("Failed to create sleep_time debug file\n");
+                return -ENOMEM;
+        }
+
+        return 0;
+}
+late_initcall(tk_debug_sleep_time_init);
+
+void tk_debug_account_sleep_time(struct timespec *t)
+{
+        sleep_time_bin[fls(t->tv_sec)]++;
+}
+