From 2337e879e8805a630b418f3e73a98084d4724b83 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Wed, 24 May 2017 10:15:26 +0200 Subject: [PATCH] s390/kernel: Use stop_machine_cpuslocked() stp_work_fn() holds get_online_cpus() while invoking stop_machine(). 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. Convert *_online_cpus() to the new interfaces while at it. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Acked-by: Ingo Molnar Acked-by: Heiko Carstens Cc: Paul E. McKenney Cc: linux-s390@vger.kernel.org Cc: Peter Zijlstra Cc: Steven Rostedt Cc: David Hildenbrand Cc: Martin Schwidefsky Link: http://lkml.kernel.org/r/20170524081548.250203087@linutronix.de --- arch/s390/kernel/time.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c index c3a52f9a69a0..192efdfac918 100644 --- a/arch/s390/kernel/time.c +++ b/arch/s390/kernel/time.c @@ -636,10 +636,10 @@ static void stp_work_fn(struct work_struct *work) goto out_unlock; memset(&stp_sync, 0, sizeof(stp_sync)); - get_online_cpus(); + cpus_read_lock(); atomic_set(&stp_sync.cpus, num_online_cpus() - 1); - stop_machine(stp_sync_clock, &stp_sync, cpu_online_mask); - put_online_cpus(); + stop_machine_cpuslocked(stp_sync_clock, &stp_sync, cpu_online_mask); + cpus_read_unlock(); if (!check_sync_clock()) /* -- 2.20.1