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-rw-r--r--drivers/base/cpu.c3
-rw-r--r--include/linux/tick.h2
-rw-r--r--kernel/time/tick-sched.c11
3 files changed, 12 insertions, 4 deletions
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index 182c6122f815..c1815b9dae68 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -487,7 +487,8 @@ static const struct attribute_group *cpu_root_attr_groups[] = {
bool cpu_is_hotpluggable(unsigned int cpu)
{
struct device *dev = get_cpu_device(cpu);
- return dev && container_of(dev, struct cpu, dev)->hotpluggable;
+ return dev && container_of(dev, struct cpu, dev)->hotpluggable
+ && tick_nohz_cpu_hotpluggable(cpu);
}
EXPORT_SYMBOL_GPL(cpu_is_hotpluggable);
diff --git a/include/linux/tick.h b/include/linux/tick.h
index bfd571f18cfd..9459fef5b857 100644
--- a/include/linux/tick.h
+++ b/include/linux/tick.h
@@ -216,6 +216,7 @@ extern void tick_nohz_dep_set_signal(struct task_struct *tsk,
enum tick_dep_bits bit);
extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
enum tick_dep_bits bit);
+extern bool tick_nohz_cpu_hotpluggable(unsigned int cpu);
/*
* The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
@@ -280,6 +281,7 @@ static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
static inline void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
static inline void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
+static inline bool tick_nohz_cpu_hotpluggable(unsigned int cpu) { return true; }
static inline void tick_dep_set(enum tick_dep_bits bit) { }
static inline void tick_dep_clear(enum tick_dep_bits bit) { }
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index b0e3c9205946..68d81a4283c8 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -527,7 +527,7 @@ void __init tick_nohz_full_setup(cpumask_var_t cpumask)
tick_nohz_full_running = true;
}
-static int tick_nohz_cpu_down(unsigned int cpu)
+bool tick_nohz_cpu_hotpluggable(unsigned int cpu)
{
/*
* The tick_do_timer_cpu CPU handles housekeeping duty (unbound
@@ -535,8 +535,13 @@ static int tick_nohz_cpu_down(unsigned int cpu)
* CPUs. It must remain online when nohz full is enabled.
*/
if (tick_nohz_full_running && tick_do_timer_cpu == cpu)
- return -EBUSY;
- return 0;
+ return false;
+ return true;
+}
+
+static int tick_nohz_cpu_down(unsigned int cpu)
+{
+ return tick_nohz_cpu_hotpluggable(cpu) ? 0 : -EBUSY;
}
void __init tick_nohz_init(void)