[PATCH 5.14 219/849] rcu-tasks: Move RTGS_WAIT_CBS to beginning of rcu_tasks_kthread() loop

Greg Kroah-Hartman
2021-11-16T01:32:32Z

From: Paul E. McKenney <paulmck@kernel.org>

[ Upstream commit 0db7c32ad3160ae06f497d48a74bd46a2a35e6bf ]

Early in debugging, it made some sense to differentiate the first
iteration from subsequent iterations, but now this just causes confusion.
This commit therefore moves the "set_tasks_gp_state(rtp, RTGS_WAIT_CBS)"
statement to the beginning of the "for" loop in rcu_tasks_kthread().

Reported-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
kernel/rcu/tasks.h | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
index 8536c55df5142..fd3909c59b6a4 100644
--- a/kernel/rcu/tasks.h
+++ b/kernel/rcu/tasks.h
@@ -197,6 +197,7 @@ static int __noreturn rcu_tasks_kthread(void *arg)
* This loop is terminated by the system going down. ;-)
*/
for (;;) {
+ set_tasks_gp_state(rtp, RTGS_WAIT_CBS);

/* Pick up any new callbacks. */
raw_spin_lock_irqsave(&rtp->cbs_lock, flags);
@@ -236,8 +237,6 @@ static int __noreturn rcu_tasks_kthread(void *arg)
}
/* Paranoid sleep to keep this from entering a tight loop */
schedule_timeout_idle(rtp->gp_sleep);
-
- set_tasks_gp_state(rtp, RTGS_WAIT_CBS);
}
}

--
2.33.0