rcu: Export rcu_scheduler_active

[karo-tx-linux.git] / init / Kconfig

diff --git a/init/Kconfig b/init/Kconfig
index d95ca7cd5d45f092fe33e175a577e0a94675c549..42bf914b325af249784468022b70db98f54f0b7a 100644 (file)
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -396,6 +396,22 @@ config RCU_FANOUT_EXACT
 
          Say N if unsure.
 
+config RCU_FAST_NO_HZ
+       bool "Accelerate last non-dyntick-idle CPU's grace periods"
+       depends on TREE_RCU && NO_HZ && SMP
+       default n
+       help
+         This option causes RCU to attempt to accelerate grace periods
+         in order to allow the final CPU to enter dynticks-idle state
+         more quickly.  On the other hand, this option increases the
+         overhead of the dynticks-idle checking, particularly on systems
+         with large numbers of CPUs.
+
+         Say Y if energy efficiency is critically important, particularly
+               if you have relatively few CPUs.
+
+         Say N if you are unsure.
+
 config TREE_RCU_TRACE
        def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU )
        select DEBUG_FS