Merge branch 'core-fixes-for-linus' of...

	/* Take cpucontrol mutex to protect against CPU hotplug */

	mutex_lock(&rcu_barrier_mutex);

	init_completion(&rcu_barrier_completion);

	atomic_set(&rcu_barrier_cpu_count, 0);

	/*

	 * The queueing of callbacks in all CPUs must be atomic with

	 * respect to RCU, otherwise one CPU may queue a callback,

	 * wait for a grace period, decrement barrier count and call

	 * complete(), while other CPUs have not yet queued anything.

	 * So, we need to make sure that grace periods cannot complete

	 * until all the callbacks are queued.

	 * Initialize rcu_barrier_cpu_count to 1, then invoke

	 * rcu_barrier_func() on each CPU, so that each CPU also has

	 * incremented rcu_barrier_cpu_count.  Only then is it safe to

	 * decrement rcu_barrier_cpu_count -- otherwise the first CPU

	 * might complete its grace period before all of the other CPUs

	 * did their increment, causing this function to return too

	 * early.

	 */

	rcu_read_lock();

	atomic_set(&rcu_barrier_cpu_count, 1);

	on_each_cpu(rcu_barrier_func, (void *)type, 1);

	rcu_read_unlock();

	if (atomic_dec_and_test(&rcu_barrier_cpu_count))

		complete(&rcu_barrier_completion);

	wait_for_completion(&rcu_barrier_completion);

	mutex_unlock(&rcu_barrier_mutex);

}