rcu: Move end of special early-boot RCU operation earlier

Ingo was getting warnings from rcu_scheduler_starting()
indicating that context switches had occurred before RCU ended
its special early-boot handling of grace periods.

This is a dangerous condition, as it indicates that RCU might
have prematurely ended grace periods.  This exploratory fix
moves rcu_scheduler_starting() earlier in boot.

Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 1 insertions, 1 deletions

diff --git a/init/main.c b/init/main.c
index 11f4f145be3f..525f6fb2bd22 100644
--- a/init/main.c
+++ b/init/main.c
@@ -451,6 +451,7 @@ static noinline void __init_refok rest_init(void)
 {
         int pid;
 
+        rcu_scheduler_starting();
         kernel_thread(kernel_init, NULL, CLONE_FS | CLONE_SIGHAND);
         numa_default_policy();
         pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
@@ -462,7 +463,6 @@ static noinline void __init_refok rest_init(void)
          * at least once to get things moving:
          */
         init_idle_bootup_task(current);
-        rcu_scheduler_starting();
         preempt_enable_no_resched();
         schedule();
         preempt_disable();