[PATCH 4/7] rcutorture: Suppress "Writer stall state" reports during boot

From: Paul E. McKenney
Date: Fri Aug 15 2025 - 20:10:23 EST


When rcutorture is running on only the one boot-time CPU while that CPU
is busy invoking initcall() functions, the added load is quite likely to
unduly delay the RCU grace-period kthread, rcutorture readers, and much
else besides. This can result in rcu_torture_stats_print() reporting
rcutorture writer stalls, which are not really a bug in that environment.
After all, one CPU can only do so much.

This commit therefore suppresses rcutorture writer stalls while the
kernel is booting, that is, while rcu_inkernel_boot_has_ended() continues
returning false.

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
kernel/rcu/rcutorture.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 7a893d51d02b6a..49e048da4f6810 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -2756,7 +2756,8 @@ rcu_torture_stats_print(void)
cur_ops->stats();
if (rtcv_snap == rcu_torture_current_version &&
rcu_access_pointer(rcu_torture_current) &&
- !rcu_stall_is_suppressed()) {
+ !rcu_stall_is_suppressed() &&
+ rcu_inkernel_boot_has_ended()) {
int __maybe_unused flags = 0;
unsigned long __maybe_unused gp_seq = 0;

--
2.40.1