Commit f0cf16cb authored Oct 09, 2015 by Oleg Nesterov Committed by Ingo Molnar Oct 20, 2015

stop_machine: Kill cpu_stop_threads->setup() and cpu_stop_unpark()



Now that we always use stop_machine_unpark() to wake the stopper
threas up, we can kill ->setup() and fold cpu_stop_unpark() into
stop_machine_unpark().

And we do not need stopper->lock to set stopper->enabled = true.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: heiko.carstens@de.ibm.com
Link: http://lkml.kernel.org/r/20151009160051.GA10169@redhat.com


Signed-off-by: Ingo Molnar <mingo@kernel.org>

parent c00166d8

kernel/stop_machine.c

+1 −11

Original line number	Diff line number	Diff line
		@@ -504,20 +504,11 @@ static void cpu_stop_park(unsigned int cpu)
		WARN_ON(!list_empty(&stopper->works));
		}

		static void cpu_stop_unpark(unsigned int cpu)
		{
		struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu);

		spin_lock_irq(&stopper->lock);
		stopper->enabled = true;
		spin_unlock_irq(&stopper->lock);
		}

		void stop_machine_unpark(int cpu)
		{
		struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu);

		cpu_stop_unpark(cpu);
		stopper->enabled = true;
		kthread_unpark(stopper->thread);
		}

		@@ -527,7 +518,6 @@ static struct smp_hotplug_thread cpu_stop_threads = {
		.thread_fn = cpu_stopper_thread,
		.thread_comm = "migration/%u",
		.create = cpu_stop_create,
		.setup = cpu_stop_unpark,
		.park = cpu_stop_park,
		.selfparking = true,
		};