Under PREEMPT_AUTO, CONFIG_PREEMPTION is enabled, and much like
PREEMPT_DYNAMIC, PREEMPT_AUTO also allows for dynamic switching
of preemption models.
The RCU model, however, is fixed at compile time.
Now, RCU typically selects PREEMPT_RCU if CONFIG_PREEMPTION is enabled.
Given the trade-offs between PREEMPT_RCU=y and PREEMPT_RCU=n, some
configurations might prefer the stronger forward-progress guarantees
of PREEMPT_RCU=n.
Accordingly, select PREEMPT_RCU=y only if the user selects
CONFIG_PREEMPT at compile time.
Suggested-by: Paul E. McKenney <[email protected]>
Signed-off-by: Ankur Arora <[email protected]>
---
kernel/rcu/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/rcu/Kconfig b/kernel/rcu/Kconfig
index bdd7eadb33d8..d0ecc8ef17a7 100644
--- a/kernel/rcu/Kconfig
+++ b/kernel/rcu/Kconfig
@@ -18,7 +18,7 @@ config TREE_RCU
config PREEMPT_RCU
bool
- default y if PREEMPTION
+ default y if (PREEMPT || PREEMPT_DYNAMIC || PREEMPT_RT)
select TREE_RCU
help
This option selects the RCU implementation that is
--
2.31.1