[PATCH tip/core/rcu 12/14] rcutorture: Hoist OOM registry up one level

paulmck
2020-08-31T18:04:42Z

Currently, registering and unregistering the OOM notifier is done
right before and after the test, respectively. This will not work
well for multi-threaded tests, so this commit hoists this registering
and unregistering up into the rcu_torture_fwd_prog_init() and
rcu_torture_fwd_prog_cleanup() functions.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
kernel/rcu/rcutorture.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 2b3f04e..983f82f 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -2110,13 +2110,11 @@ static int rcu_torture_fwd_prog(void *args)
do {
schedule_timeout_interruptible(fwd_progress_holdoff * HZ);
WRITE_ONCE(rcu_fwd_emergency_stop, false);
- register_oom_notifier(&rcutorture_oom_nb);
if (!IS_ENABLED(CONFIG_TINY_RCU) ||
rcu_inkernel_boot_has_ended())
rcu_torture_fwd_prog_nr(rfp, &tested, &tested_tries);
if (rcu_inkernel_boot_has_ended())
rcu_torture_fwd_prog_cr(rfp);
- unregister_oom_notifier(&rcutorture_oom_nb);

/* Avoid slow periods, better to test when busy. */
stutter_wait("rcu_torture_fwd_prog");
@@ -2159,6 +2157,7 @@ static int __init rcu_torture_fwd_prog_init(void)
mutex_lock(&rcu_fwd_mutex);
rcu_fwds = rfp;
mutex_unlock(&rcu_fwd_mutex);
+ register_oom_notifier(&rcutorture_oom_nb);
return torture_create_kthread(rcu_torture_fwd_prog, rfp, fwd_prog_task);
}

@@ -2171,6 +2170,7 @@ static void rcu_torture_fwd_prog_cleanup(void)
mutex_lock(&rcu_fwd_mutex);
rcu_fwds = NULL;
mutex_unlock(&rcu_fwd_mutex);
+ unregister_oom_notifier(&rcutorture_oom_nb);
kfree(rfp);
}

--
2.9.5