[tip: core/rcu] rcutorture: NULL rcu_torture_current earlier in cleanup code

From: tip-bot2 for Paul E. McKenney
Date: Fri Jul 31 2020 - 05:28:56 EST


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

Commit-ID: cae7cc6ba5bad320c2055ac54f73affd051e76ca
Gitweb: https://git.kernel.org/tip/cae7cc6ba5bad320c2055ac54f73affd051e76ca
Author: Paul E. McKenney <paulmck@xxxxxxxxxx>
AuthorDate: Sun, 26 Apr 2020 19:20:37 -07:00
Committer: Paul E. McKenney <paulmck@xxxxxxxxxx>
CommitterDate: Mon, 29 Jun 2020 12:01:44 -07:00

rcutorture: NULL rcu_torture_current earlier in cleanup code

Currently, the rcu_torture_current variable remains non-NULL until after
all readers have stopped. During this time, rcu_torture_stats_print()
will think that the test is still ongoing, which can result in confusing
dmesg output. This commit therefore NULLs rcu_torture_current immediately
after the rcu_torture_writer() kthread has decided to stop, thus informing
rcu_torture_stats_print() much sooner.

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
kernel/rcu/rcutorture.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 2621a33..5911207 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -1172,6 +1172,7 @@ rcu_torture_writer(void *arg)
WARN(1, "%s: rtort_pipe_count: %d\n", __func__, rcu_tortures[i].rtort_pipe_count);
}
} while (!torture_must_stop());
+ rcu_torture_current = NULL; // Let stats task know that we are done.
/* Reset expediting back to unexpedited. */
if (expediting > 0)
expediting = -expediting;
@@ -2473,7 +2474,6 @@ rcu_torture_cleanup(void)
reader_tasks[i]);
kfree(reader_tasks);
}
- rcu_torture_current = NULL;

if (fakewriter_tasks) {
for (i = 0; i < nfakewriters; i++) {