1 files changed, 10 insertions, 0 deletions

diff --git a/init/Kconfig b/init/Kconfig
index af6c7f8ba019..f6a1830165ce 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -441,6 +441,16 @@ config PREEMPT_RCU
           This option enables preemptible-RCU code that is common between
           the TREE_PREEMPT_RCU and TINY_PREEMPT_RCU implementations.
 
+config RCU_USER_QS
+        bool "Consider userspace as in RCU extended quiescent state"
+        depends on HAVE_RCU_USER_QS && SMP
+        help
+          This option sets hooks on kernel / userspace boundaries and
+          puts RCU in extended quiescent state when the CPU runs in
+          userspace. It means that when a CPU runs in userspace, it is
+          excluded from the global RCU state machine and thus doesn't
+          to keep the timer tick on for RCU.
+
 config RCU_FANOUT
         int "Tree-based hierarchical RCU fanout value"
         range 2 64 if 64BIT