[PATCH tip/core/rcu 4/6] rcutorture: Fix rcu_torture_cbflood() for callback-free RCU

Paul E. McKenney
2015-07-17T23:47:02Z

The rcu_torture_cbflood() function correctly checks for flavors of
RCU that lack analogs to call_rcu() and rcu_barrier(), but in that
case it fails to terminate correctly. In fact, it terminates so
incorrectly that segfaults can result. This commit therefore causes
rcu_torture_cbflood() to do the proper wait-for-stop procedure.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---
kernel/rcu/rcutorture.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 1cead7806ca6..e0eda3c1b621 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -823,9 +823,7 @@ rcu_torture_cbflood(void *arg)
}
if (err) {
VERBOSE_TOROUT_STRING("rcu_torture_cbflood disabled: Bad args or OOM");
- while (!torture_must_stop())
- schedule_timeout_interruptible(HZ);
- return 0;
+ goto wait_for_stop;
}
VERBOSE_TOROUT_STRING("rcu_torture_cbflood task started");
do {
@@ -844,6 +842,7 @@ rcu_torture_cbflood(void *arg)
stutter_wait("rcu_torture_cbflood");
} while (!torture_must_stop());
vfree(rhp);
+wait_for_stop:
torture_kthread_stopping("rcu_torture_cbflood");
return 0;
}
--
1.8.1.5