rcu: Make TINY_RCU depend on !PREEMPT_RCU rather than !PREEMPTION

Right now, TINY_RCU depends on (!PREEMPTION && !SMP), which has served the
kernel well for many years due to the fact that PREEMPT_RCU is normally
a synonym for PREEMPTION.  But with the advent of lazy preemption,
it will be possible to have non-preemptible RCU in a preemptible kernel,
so that kernels could be built with PREEMPT_RCU=n and PREEMPTION=y.

This commit therefore makes TINY_RCU depend on (!PREEMPT_RCU && !SMP),
thus allowing for a non-preemptible RCU in preemptible kernels.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Ankur Arora <ankur.a.arora@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>

diff --git a/kernel/rcu/Kconfig b/kernel/rcu/Kconfig
index e7d2dd2675931fac627947959f3fbb9e93aae05b..7dca0138260c35a4bc3193f973dc17731ec875dc 100644 (file)
--- a/kernel/rcu/Kconfig
+++ b/kernel/rcu/Kconfig
@@ -31,7 +31,7 @@ config PREEMPT_RCU
 
 config TINY_RCU
        bool
-       default y if !PREEMPTION && !SMP
+       default y if !PREEMPT_RCU && !SMP
        help
          This option selects the RCU implementation that is
          designed for UP systems from which real-time response