nocb: Clarify RCU nocb CPU error message

A message of the form "rcu:    !!! lDTs ." can be tracked down, but
doing so is not trivial.  This commit therefore eases this process by
adding text so that this error message now reads as follows:
"rcu:    nocb GP activity on CB-only CPU!!! lDTs ."

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 982fc5b..bbc0c07 100644 (file)
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -2417,7 +2417,7 @@ static void show_rcu_nocb_state(struct rcu_data *rdp)
            !waslocked && !wastimer && !wassleep)
                return;  /* Nothing untowards. */
 
-       pr_info("   !!! %c%c%c%c %c\n",
+       pr_info("   nocb GP activity on CB-only CPU!!! %c%c%c%c %c\n",
                "lL"[waslocked],
                "dD"[!!rdp->nocb_defer_wakeup],
                "tT"[wastimer],