rcu-tasks: Make grace-period-age message human-readable

This commit adds a few words to the informative message that appears
every ten seconds in RCU Tasks and RCU Tasks Trace grace periods.
This message currently reads as follows:

rcu_tasks_wait_gp: rcu_tasks grace period 1046 is 10088 jiffies old.

After this change, it provides additional context, instead reading
as follows:

rcu_tasks_wait_gp: rcu_tasks grace period number 1046 (since boot) is 10088 jiffies old.

Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
index f5bf6fb430dabf9ec6e2d34cb521dab03e75b2b5..b0b885e071fa8dc5d0c98d6eada159195a261f5b 100644 (file)
--- a/kernel/rcu/tasks.h
+++ b/kernel/rcu/tasks.h
@@ -728,7 +728,7 @@ static void rcu_tasks_wait_gp(struct rcu_tasks *rtp)
                if (rtsi > 0 && !reported && time_after(j, lastinfo + rtsi)) {
                        lastinfo = j;
                        rtsi = rtsi * rcu_task_stall_info_mult;
-                       pr_info("%s: %s grace period %lu is %lu jiffies old.\n",
+                       pr_info("%s: %s grace period number %lu (since boot) is %lu jiffies old.\n",
                                __func__, rtp->kname, rtp->tasks_gp_seq, j - rtp->gp_start);
                }
        }