[PATCH rcu 1/4] rcu/nocb: Fix segcblist state machine comments about bypass

From: Paul E. McKenney
Date: Tue Jun 04 2024 - 18:28:45 EST


From: Frederic Weisbecker <frederic@xxxxxxxxxx>

The parts explaining the bypass lifecycle in (de-)offloading are out
of date and/or wrong. Bypass is simply enabled whenever SEGCBLIST_RCU_CORE
flag is off.

Fix the comments accordingly.

Signed-off-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
include/linux/rcu_segcblist.h | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/include/linux/rcu_segcblist.h b/include/linux/rcu_segcblist.h
index 659d13a7ddaaa..1e5b4ef167caa 100644
--- a/include/linux/rcu_segcblist.h
+++ b/include/linux/rcu_segcblist.h
@@ -141,7 +141,7 @@ struct rcu_cblist {
* | SEGCBLIST_KTHREAD_GP |
* | |
* | CB/GP kthreads handle callbacks holding nocb_lock, local rcu_core() |
- * | handles callbacks concurrently. Bypass enqueue is enabled. |
+ * | handles callbacks concurrently. Bypass enqueue is disabled. |
* | Invoke RCU core so we make sure not to preempt it in the middle with |
* | leaving some urgent work unattended within a jiffy. |
* ----------------------------------------------------------------------------
@@ -154,8 +154,7 @@ struct rcu_cblist {
* | SEGCBLIST_KTHREAD_GP |
* | |
* | CB/GP kthreads and local rcu_core() handle callbacks concurrently |
- * | holding nocb_lock. Wake up CB and GP kthreads if necessary. Disable |
- * | bypass enqueue. |
+ * | holding nocb_lock. Wake up CB and GP kthreads if necessary. |
* ----------------------------------------------------------------------------
* |
* v
@@ -185,7 +184,7 @@ struct rcu_cblist {
* | |
* | Callbacks processed by rcu_core() from softirqs or local |
* | rcuc kthread, while holding nocb_lock. Forbid nocb_timer to be armed. |
- * | Flush pending nocb_timer. Flush nocb bypass callbacks. |
+ * | Flush pending nocb_timer. |
* ----------------------------------------------------------------------------
* |
* v
--
2.40.1