LU-13667 ptlrpc: fix endless loop issue

In ptlrpc_pinger_main, if the process to ping the recoverable
clients or obd_update_maxusage takes too long time, it could
be stuck in endless loop because of the negative value returned
by pinger_check_timeout.

Lustre-change: https://review.whamcloud.com/38915
Lustre-commit: 6be2dbb2595121fabceda86c5f7bdcb45e10b320

Change-Id: Ib7fc22b3cc31255223bc2be60224ced1a3585f87
Signed-off-by: Hongchao Zhang <hongchao@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Olaf Faaland-LLNL <faaland1@llnl.gov>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Signed-off-by: Minh Diep <mdiep@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/39344
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>

diff --git a/lustre/ptlrpc/pinger.c b/lustre/ptlrpc/pinger.c
index 6cc7f34..6710e79 100644 (file)
--- a/lustre/ptlrpc/pinger.c
+++ b/lustre/ptlrpc/pinger.c
@@ -268,13 +268,14 @@ static DECLARE_DELAYED_WORK(ping_work, ptlrpc_pinger_main);
 
 static void ptlrpc_pinger_main(struct work_struct *ws)
 {
-       time64_t this_ping = ktime_get_seconds();
-       time64_t time_to_next_wake;
+       time64_t this_ping, time_after_ping, time_to_next_wake;
        struct timeout_item *item;
        struct obd_import *imp;
        struct list_head *iter;
 
        do {
+               this_ping = ktime_get_seconds();
+
                mutex_lock(&pinger_mutex);
                list_for_each_entry(item, &timeout_list, ti_chain)
                        item->ti_cb(item, item->ti_cb_data);
@@ -290,9 +291,15 @@ static void ptlrpc_pinger_main(struct work_struct *ws)
                                ptlrpc_update_next_ping(imp, 0);
                }
                mutex_unlock(&pinger_mutex);
+
+               time_after_ping = ktime_get_seconds();
                /* update memory usage info */
                obd_update_maxusage();
 
+               if ((ktime_get_seconds() - this_ping - 3) > PING_INTERVAL)
+                       CDEBUG(D_HA, "long time to ping: %lld, %lld, %lld\n",
+                              this_ping, time_after_ping, ktime_get_seconds());
+
                /* Wait until the next ping time, or until we're stopped. */
                time_to_next_wake = pinger_check_timeout(this_ping);
                /* The ping sent by ptlrpc_send_rpc may get sent out