path: root/init
diff options
authorPaul E. McKenney <paulmck@linux.vnet.ibm.com>2013-01-08 15:48:33 -0800
committerPaul E. McKenney <paulmck@linux.vnet.ibm.com>2013-01-28 22:06:22 -0800
commit9fc52d832b5e7f6e175f3b20ae94504b780b9fd3 (patch)
treece618667492e0d87b496dad1f605674bbb6a5bc4 /init
parent6bfc09e2327dfbffc312004c16188dbf8dfb0297 (diff)
rcu: Allow TREE_PREEMPT_RCU on UP systems
The TINY_PREEMPT_RCU is complex, does not provide that much memory savings, and therefore TREE_PREEMPT_RCU should be used instead. The systems where the difference between TINY_PREEMPT_RCU and TREE_PREEMPT_RCU are quite small compared to the memory footprint of CONFIG_PREEMPT. This commit therefore takes a first step towards eliminating TINY_PREEMPT_RCU by allowing TREE_PREEMPT_RCU to be configured on !SMP systems. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Diffstat (limited to 'init')
1 files changed, 3 insertions, 1 deletions
diff --git a/init/Kconfig b/init/Kconfig
index a5e90e139ba..fb19b46c004 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -453,7 +453,7 @@ config TREE_RCU
bool "Preemptible tree-based hierarchical RCU"
- depends on PREEMPT && SMP
+ depends on PREEMPT
This option selects the RCU implementation that is
designed for very large SMP systems with hundreds or
@@ -461,6 +461,8 @@ config TREE_PREEMPT_RCU
is also required. It also scales down nicely to
smaller systems.
+ Select this option if you are unsure.
config TINY_RCU
bool "UP-only small-memory-footprint RCU"
depends on !PREEMPT && !SMP