This commit wordsmiths the RCU_LAZY and RCU_LAZY_DEFAULT_OFF Kconfig
options' help text.
Signed-off-by: Paul E. McKenney <paul...@kernel.org>
---
kernel/rcu/Kconfig | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)
diff --git a/kernel/rcu/Kconfig b/kernel/rcu/Kconfig
index b9b6bc55185db..2bb22dac3b5a9 100644
--- a/kernel/rcu/Kconfig
+++ b/kernel/rcu/Kconfig
@@ -323,21 +323,27 @@ config RCU_LAZY
depends on RCU_NOCB_CPU
default n
help
- To save power, batch RCU callbacks and flush after delay, memory
- pressure, or callback list growing too big.
+ To save power, batch RCU callbacks and delay starting the
+ corresponding grace period for multiple seconds. The grace
+ period will be started after this delay, in case of memory
+ pressure, or if the corresponding CPU's callback list grows
+ too large.
- Requires rcu_nocbs=all to be set.
+ These delays happen only on rcu_nocbs CPUs, that is, CPUs
+ whose callbacks have been offloaded.
- Use rcutree.enable_rcu_lazy=0 to turn it off at boot time.
+ Use the rcutree.enable_rcu_lazy=0 kernel-boot parameter to
+ globally disable these delays.
config RCU_LAZY_DEFAULT_OFF
bool "Turn RCU lazy invocation off by default"
depends on RCU_LAZY
default n
help
- Allows building the kernel with CONFIG_RCU_LAZY=y yet keep it default
- off. Boot time param rcutree.enable_rcu_lazy=1 can be used to switch
- it back on.
+ Build the kernel with CONFIG_RCU_LAZY=y, but cause the kernel
+ to boot with these energy-efficiency delays disabled. Use the
+ rcutree.enable_rcu_lazy=0 kernel-boot parameter to override
+ the this option at boot time, thus re-enabling these delays.
config RCU_DOUBLE_CHECK_CB_TIME
bool "RCU callback-batch backup time check"
--
2.40.1
