The variable takedown_cpu_task is never declared/used on !HOTPLUG_CPU
except for migrate_enable(). This leads to a link error.
Don't use takedown_cpu_task in !HOTPLUG_CPU.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
---
kernel/cpu.c | 2 ++
kernel/sched/core.c | 2 ++
2 files changed, 4 insertions(+)
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 123ad9626cc7f..81a6e5068972c 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -887,7 +887,9 @@ static int take_cpu_down(void *_param)
return 0;
}
+#ifdef CONFIG_PREEMPT_RT
struct task_struct *takedown_cpu_task;
+#endif
static int takedown_cpu(unsigned int cpu)
{
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index bd26257eb2358..8bea013b2baf5 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -8212,9 +8212,11 @@ void migrate_enable(void)
p->migrate_disable = 0;
rq->nr_pinned--;
+#ifdef CONFIG_HOTPLUG_CPU
if (rq->nr_pinned == 0 && unlikely(!cpu_active(cpu)) &&
takedown_cpu_task)
wake_up_process(takedown_cpu_task);
+#endif
if (!p->migrate_disable_scheduled)
goto out;
--
2.24.0
