[tip: core/rcu] rcutorture: Separate warnings for each failure type

[tip: core/rcu] rcutorture: Separate warnings for each failure type

[tip-bot2 for Paul E. McKenney]

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

Commit-ID:     8b5ddf8b99dc42241d1d413c6685bce18275c40e
Gitweb:        https://git.kernel.org/tip/8b5ddf8b99dc42241d1d413c6685bce18275c40e
Author:        Paul E. McKenney <paulmck@kernel.org>
AuthorDate:    Wed, 14 Aug 2019 12:02:40 -07:00
Committer:     Paul E. McKenney <paulmck@kernel.org>
CommitterDate: Sat, 05 Oct 2019 11:50:03 -07:00

rcutorture: Separate warnings for each failure type

Currently, each of six different types of failure triggers a
single WARN_ON_ONCE(), and it is then necessary to stare at the
rcu_torture_stats(), Reader Pipe, and Reader Batch lines looking for
inappropriately non-zero values.  This can be annoying and error-prone,
so this commit provides a separate WARN_ON_ONCE() for each of the
six error conditions and adds short comments to each to ease error
identification.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
 kernel/rcu/rcutorture.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 3c9feca..5ac4672 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -1442,15 +1442,18 @@ rcu_torture_stats_print(void)
 		n_rcu_torture_barrier_error);
 
 	pr_alert("%s%s ", torture_type, TORTURE_FLAG);
-	if (atomic_read(&n_rcu_torture_mberror) != 0 ||
-	    n_rcu_torture_barrier_error != 0 ||
-	    n_rcu_torture_boost_ktrerror != 0 ||
-	    n_rcu_torture_boost_rterror != 0 ||
-	    n_rcu_torture_boost_failure != 0 ||
+	if (atomic_read(&n_rcu_torture_mberror) ||
+	    n_rcu_torture_barrier_error || n_rcu_torture_boost_ktrerror ||
+	    n_rcu_torture_boost_rterror || n_rcu_torture_boost_failure ||
 	    i > 1) {
 		pr_cont("%s", "!!! ");
 		atomic_inc(&n_rcu_torture_error);
-		WARN_ON_ONCE(1);
+		WARN_ON_ONCE(atomic_read(&n_rcu_torture_mberror));
+		WARN_ON_ONCE(n_rcu_torture_barrier_error);  // rcu_barrier()
+		WARN_ON_ONCE(n_rcu_torture_boost_ktrerror); // no boost kthread
+		WARN_ON_ONCE(n_rcu_torture_boost_rterror); // can't set RT prio
+		WARN_ON_ONCE(n_rcu_torture_boost_failure); // RCU boost failed
+		WARN_ON_ONCE(i > 1); // Too-short grace period
 	}
 	pr_cont("Reader Pipe: ");
 	for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++)