2 files changed, 243 insertions, 238 deletions

diff --git a/init/Kconfig b/init/Kconfig
index dc431c6109f2..bc4c180c66a5 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -472,244 +472,7 @@ config TASK_IO_ACCOUNTING
 
 endmenu # "CPU/Task time and stats accounting"
 
-menu "RCU Subsystem"
-
-config TREE_RCU
-        bool
-        default y if !PREEMPT && SMP
-        help
-          This option selects the RCU implementation that is
-          designed for very large SMP system with hundreds or
-          thousands of CPUs.  It also scales down nicely to
-          smaller systems.
-
-config PREEMPT_RCU
-        bool
-        default y if PREEMPT
-        help
-          This option selects the RCU implementation that is
-          designed for very large SMP systems with hundreds or
-          thousands of CPUs, but for which real-time response
-          is also required.  It also scales down nicely to
-          smaller systems.
-
-          Select this option if you are unsure.
-
-config TINY_RCU
-        bool
-        default y if !PREEMPT && !SMP
-        help
-          This option selects the RCU implementation that is
-          designed for UP systems from which real-time response
-          is not required.  This option greatly reduces the
-          memory footprint of RCU.
-
-config RCU_EXPERT
-        bool "Make expert-level adjustments to RCU configuration"
-        default n
-        help
-          This option needs to be enabled if you wish to make
-          expert-level adjustments to RCU configuration.  By default,
-          no such adjustments can be made, which has the often-beneficial
-          side-effect of preventing "make oldconfig" from asking you all
-          sorts of detailed questions about how you would like numerous
-          obscure RCU options to be set up.
-
-          Say Y if you need to make expert-level adjustments to RCU.
-
-          Say N if you are unsure.
-
-config SRCU
-        bool
-        help
-          This option selects the sleepable version of RCU. This version
-          permits arbitrary sleeping or blocking within RCU read-side critical
-          sections.
-
-config TINY_SRCU
-        bool
-        default y if SRCU && TINY_RCU
-        help
-          This option selects the single-CPU non-preemptible version of SRCU.
-
-config TREE_SRCU
-        bool
-        default y if SRCU && !TINY_RCU
-        help
-          This option selects the full-fledged version of SRCU.
-
-config TASKS_RCU
-        bool
-        default n
-        select SRCU
-        help
-          This option enables a task-based RCU implementation that uses
-          only voluntary context switch (not preemption!), idle, and
-          user-mode execution as quiescent states.
-
-config RCU_STALL_COMMON
-        def_bool ( TREE_RCU || PREEMPT_RCU || RCU_TRACE )
-        help
-          This option enables RCU CPU stall code that is common between
-          the TINY and TREE variants of RCU.  The purpose is to allow
-          the tiny variants to disable RCU CPU stall warnings, while
-          making these warnings mandatory for the tree variants.
-
-config RCU_NEED_SEGCBLIST
-        def_bool ( TREE_RCU || PREEMPT_RCU || TREE_SRCU )
-
-config CONTEXT_TRACKING
-       bool
-
-config CONTEXT_TRACKING_FORCE
-        bool "Force context tracking"
-        depends on CONTEXT_TRACKING
-        default y if !NO_HZ_FULL
-        help
-          The major pre-requirement for full dynticks to work is to
-          support the context tracking subsystem. But there are also
-          other dependencies to provide in order to make the full
-          dynticks working.
-
-          This option stands for testing when an arch implements the
-          context tracking backend but doesn't yet fullfill all the
-          requirements to make the full dynticks feature working.
-          Without the full dynticks, there is no way to test the support
-          for context tracking and the subsystems that rely on it: RCU
-          userspace extended quiescent state and tickless cputime
-          accounting. This option copes with the absence of the full
-          dynticks subsystem by forcing the context tracking on all
-          CPUs in the system.
-
-          Say Y only if you're working on the development of an
-          architecture backend for the context tracking.
-
-          Say N otherwise, this option brings an overhead that you
-          don't want in production.
-
-
-config RCU_FANOUT
-        int "Tree-based hierarchical RCU fanout value"
-        range 2 64 if 64BIT
-        range 2 32 if !64BIT
-        depends on (TREE_RCU || PREEMPT_RCU) && RCU_EXPERT
-        default 64 if 64BIT
-        default 32 if !64BIT
-        help
-          This option controls the fanout of hierarchical implementations
-          of RCU, allowing RCU to work efficiently on machines with
-          large numbers of CPUs.  This value must be at least the fourth
-          root of NR_CPUS, which allows NR_CPUS to be insanely large.
-          The default value of RCU_FANOUT should be used for production
-          systems, but if you are stress-testing the RCU implementation
-          itself, small RCU_FANOUT values allow you to test large-system
-          code paths on small(er) systems.
-
-          Select a specific number if testing RCU itself.
-          Take the default if unsure.
-
-config RCU_FANOUT_LEAF
-        int "Tree-based hierarchical RCU leaf-level fanout value"
-        range 2 64 if 64BIT
-        range 2 32 if !64BIT
-        depends on (TREE_RCU || PREEMPT_RCU) && RCU_EXPERT
-        default 16
-        help
-          This option controls the leaf-level fanout of hierarchical
-          implementations of RCU, and allows trading off cache misses
-          against lock contention.  Systems that synchronize their
-          scheduling-clock interrupts for energy-efficiency reasons will
-          want the default because the smaller leaf-level fanout keeps
-          lock contention levels acceptably low.  Very large systems
-          (hundreds or thousands of CPUs) will instead want to set this
-          value to the maximum value possible in order to reduce the
-          number of cache misses incurred during RCU's grace-period
-          initialization.  These systems tend to run CPU-bound, and thus
-          are not helped by synchronized interrupts, and thus tend to
-          skew them, which reduces lock contention enough that large
-          leaf-level fanouts work well.  That said, setting leaf-level
-          fanout to a large number will likely cause problematic
-          lock contention on the leaf-level rcu_node structures unless
-          you boot with the skew_tick kernel parameter.
-
-          Select a specific number if testing RCU itself.
-
-          Select the maximum permissible value for large systems, but
-          please understand that you may also need to set the skew_tick
-          kernel boot parameter to avoid contention on the rcu_node
-          structure's locks.
-
-          Take the default if unsure.
-
-config RCU_FAST_NO_HZ
-        bool "Accelerate last non-dyntick-idle CPU's grace periods"
-        depends on NO_HZ_COMMON && SMP && RCU_EXPERT
-        default n
-        help
-          This option permits CPUs to enter dynticks-idle state even if
-          they have RCU callbacks queued, and prevents RCU from waking
-          these CPUs up more than roughly once every four jiffies (by
-          default, you can adjust this using the rcutree.rcu_idle_gp_delay
-          parameter), thus improving energy efficiency.  On the other
-          hand, this option increases the duration of RCU grace periods,
-          for example, slowing down synchronize_rcu().
-
-          Say Y if energy efficiency is critically important, and you
-                don't care about increased grace-period durations.
-
-          Say N if you are unsure.
-
-config RCU_BOOST
-        bool "Enable RCU priority boosting"
-        depends on RT_MUTEXES && PREEMPT_RCU && RCU_EXPERT
-        default n
-        help
-          This option boosts the priority of preempted RCU readers that
-          block the current preemptible RCU grace period for too long.
-          This option also prevents heavy loads from blocking RCU
-          callback invocation for all flavors of RCU.
-
-          Say Y here if you are working with real-time apps or heavy loads
-          Say N here if you are unsure.
-
-config RCU_BOOST_DELAY
-        int "Milliseconds to delay boosting after RCU grace-period start"
-        range 0 3000
-        depends on RCU_BOOST
-        default 500
-        help
-          This option specifies the time to wait after the beginning of
-          a given grace period before priority-boosting preempted RCU
-          readers blocking that grace period.  Note that any RCU reader
-          blocking an expedited RCU grace period is boosted immediately.
+source "kernel/rcu/Kconfig"