ocfs2/cluster: Fix output in file elapsed_time_in_ms

The o2hb debugfs file, elapsed_time_in_ms, should return values only after the
timer is armed atleast once.

Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>

diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c
index 4728a746281df6b29a1dcc52bdf30d315b86b2ef..a4e855e3690e6ab844d37788b71649975321cb19 100644 (file)
--- a/fs/ocfs2/cluster/heartbeat.c
+++ b/fs/ocfs2/cluster/heartbeat.c
@@ -1198,6 +1198,7 @@ static int o2hb_debug_open(struct inode *inode, struct file *file)
        struct o2hb_debug_buf *db = inode->i_private;
        struct o2hb_region *reg;
        unsigned long map[BITS_TO_LONGS(O2NM_MAX_NODES)];
+       unsigned long lts;
        char *buf = NULL;
        int i = -1;
        int out = 0;
@@ -1234,9 +1235,11 @@ static int o2hb_debug_open(struct inode *inode, struct file *file)
 
        case O2HB_DB_TYPE_REGION_ELAPSED_TIME:
                reg = (struct o2hb_region *)db->db_data;
-               out += snprintf(buf + out, PAGE_SIZE - out, "%u\n",
-                               jiffies_to_msecs(jiffies -
-                                                reg->hr_last_timeout_start));
+               lts = reg->hr_last_timeout_start;
+               /* If 0, it has never been set before */
+               if (lts)
+                       lts = jiffies_to_msecs(jiffies - lts);
+               out += snprintf(buf + out, PAGE_SIZE - out, "%lu\n", lts);
                goto done;
 
        case O2HB_DB_TYPE_REGION_PINNED: