rcutorture: Print forward-progress test age upon failure

This commit prints the age of the forward-progress test in jiffies,
in order to allow better interpretation of the callback-invocation
histograms.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 329f4fb13125..080b5ac6340c 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -1639,7 +1639,8 @@ static void rcu_torture_fwd_cb_hist(void)
         for (i = ARRAY_SIZE(n_launders_hist) - 1; i > 0; i--)
                 if (n_launders_hist[i] > 0)
                         break;
-        pr_alert("%s: Callback-invocation histogram:", __func__);
+        pr_alert("%s: Callback-invocation histogram (duration %lu jiffies):",
+                 __func__, jiffies - rcu_fwd_startat);
         for (j = 0; j <= i; j++)
                 pr_cont(" %ds: %ld", j + 1, n_launders_hist[j]);
         pr_cont("\n");