rcu: Make RCU able to tolerate undefined CONFIG_RCU_KTHREAD_PRIO
This commit updates the initialization of the kthread_prio boot parameter
so that RCU will build even when CONFIG_RCU_KTHREAD_PRIO is undefined.
The kthread_prio boot parameter is set to CONFIG_RCU_KTHREAD_PRIO if
that is defined, otherwise to 1 if CONFIG_RCU_BOOST is defined and
to zero otherwise. This commit then makes CONFIG_RCU_KTHREAD_PRIO
depend on CONFIG_RCU_EXPERT, so that Kconfig users won't be asked about
CONFIG_RCU_KTHREAD_PRIO unless they want to be.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
diff --git a/init/Kconfig b/init/Kconfig
index 7817600..af2c93c4 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -671,6 +671,7 @@
range 0 99 if !RCU_BOOST
default 1 if RCU_BOOST
default 0 if !RCU_BOOST
+ depends on RCU_EXPERT
help
This option specifies the SCHED_FIFO priority value that will be
assigned to the rcuc/n and rcub/n threads and is also the value