[PATCH rcu 3/7] doc: Use rcu_barrier() to rate-limit RCU callbacks

From: Paul E. McKenney
Date: Wed Aug 31 2022 - 14:07:03 EST


The checklist.rst document advises periodic synchronize_rcu() invocations
to prevent callback flooding. However, rcu_barrier() is often a better
choice. This commit therefore adds words to this effect.

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
Documentation/RCU/checklist.rst | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Documentation/RCU/checklist.rst b/Documentation/RCU/checklist.rst
index 2db206fc3465f..178ca7547b987 100644
--- a/Documentation/RCU/checklist.rst
+++ b/Documentation/RCU/checklist.rst
@@ -305,7 +305,8 @@ over a rather long period of time, but improvements are always welcome!
the machine.

d. Periodically invoke synchronize_rcu(), permitting a limited
- number of updates per grace period.
+ number of updates per grace period. Better yet, periodically
+ invoke rcu_barrier() to wait for all outstanding callbacks.

The same cautions apply to call_srcu() and kfree_rcu().

--
2.31.1.189.g2e36527f23