@@ -3145,12 +3145,12 @@ static int __init rcu_torture_fwd_prog_init(void)
fwd_progress = 0;
return 0;
}
- if (stall_cpu > 0) {
- VERBOSE_TOROUT_STRING("rcu_torture_fwd_prog_init: Disabled, conflicts with CPU-stall testing");
+ if (stall_cpu > 0 || (preempt_duration > 0 && IS_ENABLED(CONFIG_RCU_NOCB_CPU))) {
+ VERBOSE_TOROUT_STRING("rcu_torture_fwd_prog_init: Disabled, conflicts with CPU-stall and/or preemption testing");
fwd_progress = 0;
if (IS_MODULE(CONFIG_RCU_TORTURE_TEST))
return -EINVAL; /* In module, can fail back to user. */
- WARN_ON(1); /* Make sure rcutorture notices conflict. */
+ WARN_ON(1); /* Make sure rcutorture scripting notices conflict. */
return 0;
}
if (fwd_progress_holdoff <= 0)
Use of the rcutorture preempt_duration and the default-on fwd_progress kernel parameters can result in preemption of callback processing during forward-progress testing, which is an excellent way to OOM your test if your kernel offloads RCU callbacks. This commit therefore treats preempt_duration in the same way as stall_cpu in CONFIG_RCU_NOCB_CPU=y kernels, prohibiting fwd_progress testing and splatting when rcutorture is built in (as opposed to being a loadable module). Signed-off-by: Paul E. McKenney <paulmck@kernel.org> --- kernel/rcu/rcutorture.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)