[tip: core/rcu] nocb: Clarify RCU nocb CPU error message

[tip-bot2 for Paul E. McKenney]

The following commit has been merged into the core/rcu branch of tip:

Commit-ID:     e082c7b38185af0f59e55efff840939c35391f85
Gitweb:        https://git.kernel.org/tip/e082c7b38185af0f59e55efff840939c35391f85
Author:        Paul E. McKenney <paulmck@xxxxxxxxxx>
AuthorDate:    Mon, 22 Jun 2020 09:25:34 -07:00
Committer:     Paul E. McKenney <paulmck@xxxxxxxxxx>
CommitterDate: Mon, 24 Aug 2020 18:36:05 -07:00

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@xxxxxxxxxx>
---
 kernel/rcu/tree_plugin.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 982fc5b..bbc0c07 100644
--- 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],