rcu: Directly drive TASKS_RCU from Kconfig

Currently, Kconfig will ask the user whether TASKS_RCU should be set.
This is silly because Kconfig already has all the information that it
needs to set this parameter.  This commit therefore directly drives
the value of TASKS_RCU via "select" statements.  Which means that
as subsystems require TASKS_RCU, those subsystems will need to add
"select" statements of their own.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>

diff --git a/init/Kconfig b/init/Kconfig
index dc24dec6023292ac6f1bd484ce506074d3e53566..73db30a76afa33e729612a44a285040b5f9e19e1 100644 (file)
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -509,7 +509,7 @@ config SRCU
          sections.
 
 config TASKS_RCU
-       bool "Task_based RCU implementation using voluntary context switch"
+       bool
        default n
        select SRCU
        help
@@ -517,8 +517,6 @@ config TASKS_RCU
          only voluntary context switch (not preemption!), idle, and
          user-mode execution as quiescent states.
 
-         If unsure, say N.
-
 config RCU_STALL_COMMON
        def_bool ( TREE_RCU || PREEMPT_RCU || RCU_TRACE )
        help

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index e1af93ae246b93cf4ba9398c46a73439c363ccef..c4e1cf04cf57a4edbfab2d8e6b2e6c61526deb44 100644 (file)
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1233,6 +1233,7 @@ config RCU_TORTURE_TEST
        depends on DEBUG_KERNEL
        select TORTURE_TEST
        select SRCU
+       select TASKS_RCU
        default n
        help
          This option provides a kernel module that runs torture tests