Commit-ID: 210e21331fc3a396af640cec652be769d146e49f Gitweb: http://git.kernel.org/tip/210e21331fc3a396af640cec652be769d146e49f Author: Sebastian Andrzej Siewior <[email protected]> AuthorDate: Wed, 24 May 2017 10:15:28 +0200 Committer: Thomas Gleixner <[email protected]> CommitDate: Fri, 26 May 2017 10:10:42 +0200
cpu/hotplug: Use stop_machine_cpuslocked() in takedown_cpu() takedown_cpu() is a cpu hotplug function invoking stop_machine(). The cpu hotplug machinery holds the hotplug lock for write. stop_machine() invokes get_online_cpus() as well. This is correct, but prevents the conversion of the hotplug locking to a percpu rwsem. Use stop_machine_cpuslocked() to avoid the nested call. Signed-off-by: Sebastian Andrzej Siewior <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: Paul E. McKenney <[email protected]> Acked-by: Ingo Molnar <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Steven Rostedt <[email protected]> Link: http://lkml.kernel.org/r/[email protected] --- kernel/cpu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/cpu.c b/kernel/cpu.c index e4389ac..142d889 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -701,7 +701,7 @@ static int takedown_cpu(unsigned int cpu) /* * So now all preempt/rcu users must observe !cpu_active(). */ - err = stop_machine(take_cpu_down, NULL, cpumask_of(cpu)); + err = stop_machine_cpuslocked(take_cpu_down, NULL, cpumask_of(cpu)); if (err) { /* CPU refused to die */ irq_unlock_sparse();
