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-rw-r--r--kernel/cpu.c418
1 files changed, 305 insertions, 113 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 1c8ddd6ee94..a343bde710b 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -10,22 +10,52 @@
#include <linux/sched.h>
#include <linux/unistd.h>
#include <linux/cpu.h>
-#include <linux/module.h>
+#include <linux/oom.h>
+#include <linux/rcupdate.h>
+#include <linux/export.h>
+#include <linux/bug.h>
#include <linux/kthread.h>
#include <linux/stop_machine.h>
#include <linux/mutex.h>
+#include <linux/gfp.h>
+#include <linux/suspend.h>
+#include <linux/lockdep.h>
+#include <trace/events/power.h>
+
+#include "smpboot.h"
#ifdef CONFIG_SMP
/* Serializes the updates to cpu_online_mask, cpu_present_mask */
static DEFINE_MUTEX(cpu_add_remove_lock);
-static __cpuinitdata RAW_NOTIFIER_HEAD(cpu_chain);
+/*
+ * The following two APIs (cpu_maps_update_begin/done) must be used when
+ * attempting to serialize the updates to cpu_online_mask & cpu_present_mask.
+ * The APIs cpu_notifier_register_begin/done() must be used to protect CPU
+ * hotplug callback (un)registration performed using __register_cpu_notifier()
+ * or __unregister_cpu_notifier().
+ */
+void cpu_maps_update_begin(void)
+{
+ mutex_lock(&cpu_add_remove_lock);
+}
+EXPORT_SYMBOL(cpu_notifier_register_begin);
+
+void cpu_maps_update_done(void)
+{
+ mutex_unlock(&cpu_add_remove_lock);
+}
+EXPORT_SYMBOL(cpu_notifier_register_done);
+
+static RAW_NOTIFIER_HEAD(cpu_chain);
/* If set, cpu_up and cpu_down will return -EBUSY and do nothing.
* Should always be manipulated under cpu_add_remove_lock
*/
static int cpu_hotplug_disabled;
+#ifdef CONFIG_HOTPLUG_CPU
+
static struct {
struct task_struct *active_writer;
struct mutex lock; /* Synchronizes accesses to refcount, */
@@ -34,19 +64,30 @@ static struct {
* an ongoing cpu hotplug operation.
*/
int refcount;
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif
} cpu_hotplug = {
.active_writer = NULL,
.lock = __MUTEX_INITIALIZER(cpu_hotplug.lock),
.refcount = 0,
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ .dep_map = {.name = "cpu_hotplug.lock" },
+#endif
};
-#ifdef CONFIG_HOTPLUG_CPU
+/* Lockdep annotations for get/put_online_cpus() and cpu_hotplug_begin/end() */
+#define cpuhp_lock_acquire_read() lock_map_acquire_read(&cpu_hotplug.dep_map)
+#define cpuhp_lock_acquire() lock_map_acquire(&cpu_hotplug.dep_map)
+#define cpuhp_lock_release() lock_map_release(&cpu_hotplug.dep_map)
void get_online_cpus(void)
{
might_sleep();
if (cpu_hotplug.active_writer == current)
return;
+ cpuhp_lock_acquire_read();
mutex_lock(&cpu_hotplug.lock);
cpu_hotplug.refcount++;
mutex_unlock(&cpu_hotplug.lock);
@@ -59,29 +100,18 @@ void put_online_cpus(void)
if (cpu_hotplug.active_writer == current)
return;
mutex_lock(&cpu_hotplug.lock);
+
+ if (WARN_ON(!cpu_hotplug.refcount))
+ cpu_hotplug.refcount++; /* try to fix things up */
+
if (!--cpu_hotplug.refcount && unlikely(cpu_hotplug.active_writer))
wake_up_process(cpu_hotplug.active_writer);
mutex_unlock(&cpu_hotplug.lock);
+ cpuhp_lock_release();
}
EXPORT_SYMBOL_GPL(put_online_cpus);
-#endif /* CONFIG_HOTPLUG_CPU */
-
-/*
- * The following two API's must be used when attempting
- * to serialize the updates to cpu_online_mask, cpu_present_mask.
- */
-void cpu_maps_update_begin(void)
-{
- mutex_lock(&cpu_add_remove_lock);
-}
-
-void cpu_maps_update_done(void)
-{
- mutex_unlock(&cpu_add_remove_lock);
-}
-
/*
* This ensures that the hotplug operation can begin only when the
* refcount goes to zero.
@@ -104,10 +134,11 @@ void cpu_maps_update_done(void)
* get_online_cpus() not an api which is called all that often.
*
*/
-static void cpu_hotplug_begin(void)
+void cpu_hotplug_begin(void)
{
cpu_hotplug.active_writer = current;
+ cpuhp_lock_acquire();
for (;;) {
mutex_lock(&cpu_hotplug.lock);
if (likely(!cpu_hotplug.refcount))
@@ -118,11 +149,36 @@ static void cpu_hotplug_begin(void)
}
}
-static void cpu_hotplug_done(void)
+void cpu_hotplug_done(void)
{
cpu_hotplug.active_writer = NULL;
mutex_unlock(&cpu_hotplug.lock);
+ cpuhp_lock_release();
}
+
+/*
+ * Wait for currently running CPU hotplug operations to complete (if any) and
+ * disable future CPU hotplug (from sysfs). The 'cpu_add_remove_lock' protects
+ * the 'cpu_hotplug_disabled' flag. The same lock is also acquired by the
+ * hotplug path before performing hotplug operations. So acquiring that lock
+ * guarantees mutual exclusion from any currently running hotplug operations.
+ */
+void cpu_hotplug_disable(void)
+{
+ cpu_maps_update_begin();
+ cpu_hotplug_disabled = 1;
+ cpu_maps_update_done();
+}
+
+void cpu_hotplug_enable(void)
+{
+ cpu_maps_update_begin();
+ cpu_hotplug_disabled = 0;
+ cpu_maps_update_done();
+}
+
+#endif /* CONFIG_HOTPLUG_CPU */
+
/* Need to know about CPUs going up/down? */
int __ref register_cpu_notifier(struct notifier_block *nb)
{
@@ -133,9 +189,35 @@ int __ref register_cpu_notifier(struct notifier_block *nb)
return ret;
}
+int __ref __register_cpu_notifier(struct notifier_block *nb)
+{
+ return raw_notifier_chain_register(&cpu_chain, nb);
+}
+
+static int __cpu_notify(unsigned long val, void *v, int nr_to_call,
+ int *nr_calls)
+{
+ int ret;
+
+ ret = __raw_notifier_call_chain(&cpu_chain, val, v, nr_to_call,
+ nr_calls);
+
+ return notifier_to_errno(ret);
+}
+
+static int cpu_notify(unsigned long val, void *v)
+{
+ return __cpu_notify(val, v, -1, NULL);
+}
+
#ifdef CONFIG_HOTPLUG_CPU
+static void cpu_notify_nofail(unsigned long val, void *v)
+{
+ BUG_ON(cpu_notify(val, v));
+}
EXPORT_SYMBOL(register_cpu_notifier);
+EXPORT_SYMBOL(__register_cpu_notifier);
void __ref unregister_cpu_notifier(struct notifier_block *nb)
{
@@ -145,19 +227,66 @@ void __ref unregister_cpu_notifier(struct notifier_block *nb)
}
EXPORT_SYMBOL(unregister_cpu_notifier);
+void __ref __unregister_cpu_notifier(struct notifier_block *nb)
+{
+ raw_notifier_chain_unregister(&cpu_chain, nb);
+}
+EXPORT_SYMBOL(__unregister_cpu_notifier);
+
+/**
+ * clear_tasks_mm_cpumask - Safely clear tasks' mm_cpumask for a CPU
+ * @cpu: a CPU id
+ *
+ * This function walks all processes, finds a valid mm struct for each one and
+ * then clears a corresponding bit in mm's cpumask. While this all sounds
+ * trivial, there are various non-obvious corner cases, which this function
+ * tries to solve in a safe manner.
+ *
+ * Also note that the function uses a somewhat relaxed locking scheme, so it may
+ * be called only for an already offlined CPU.
+ */
+void clear_tasks_mm_cpumask(int cpu)
+{
+ struct task_struct *p;
+
+ /*
+ * This function is called after the cpu is taken down and marked
+ * offline, so its not like new tasks will ever get this cpu set in
+ * their mm mask. -- Peter Zijlstra
+ * Thus, we may use rcu_read_lock() here, instead of grabbing
+ * full-fledged tasklist_lock.
+ */
+ WARN_ON(cpu_online(cpu));
+ rcu_read_lock();
+ for_each_process(p) {
+ struct task_struct *t;
+
+ /*
+ * Main thread might exit, but other threads may still have
+ * a valid mm. Find one.
+ */
+ t = find_lock_task_mm(p);
+ if (!t)
+ continue;
+ cpumask_clear_cpu(cpu, mm_cpumask(t->mm));
+ task_unlock(t);
+ }
+ rcu_read_unlock();
+}
+
static inline void check_for_tasks(int cpu)
{
struct task_struct *p;
+ cputime_t utime, stime;
write_lock_irq(&tasklist_lock);
for_each_process(p) {
- if (task_cpu(p) == cpu &&
- (!cputime_eq(p->utime, cputime_zero) ||
- !cputime_eq(p->stime, cputime_zero)))
- printk(KERN_WARNING "Task %s (pid = %d) is on cpu %d\
- (state = %ld, flags = %x) \n",
- p->comm, task_pid_nr(p), cpu,
- p->state, p->flags);
+ task_cputime(p, &utime, &stime);
+ if (task_cpu(p) == cpu && p->state == TASK_RUNNING &&
+ (utime || stime))
+ pr_warn("Task %s (pid = %d) is on cpu %d (state = %ld, flags = %x)\n",
+ p->comm, task_pid_nr(p), cpu,
+ p->state, p->flags);
}
write_unlock_irq(&tasklist_lock);
}
@@ -178,12 +307,9 @@ static int __ref take_cpu_down(void *_param)
if (err < 0)
return err;
- raw_notifier_call_chain(&cpu_chain, CPU_DYING | param->mod,
- param->hcpu);
-
- /* Force idle task to run as soon as we yield: it should
- immediately notice cpu is offline and die quickly. */
- sched_idle_next();
+ cpu_notify(CPU_DYING | param->mod, param->hcpu);
+ /* Park the stopper thread */
+ kthread_park(current);
return 0;
}
@@ -191,7 +317,6 @@ static int __ref take_cpu_down(void *_param)
static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
{
int err, nr_calls = 0;
- cpumask_var_t old_allowed;
void *hcpu = (void *)(long)cpu;
unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
struct take_cpu_down_param tcd_param = {
@@ -205,65 +330,69 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
if (!cpu_online(cpu))
return -EINVAL;
- if (!alloc_cpumask_var(&old_allowed, GFP_KERNEL))
- return -ENOMEM;
-
cpu_hotplug_begin();
- set_cpu_active(cpu, false);
- err = __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_PREPARE | mod,
- hcpu, -1, &nr_calls);
- if (err == NOTIFY_BAD) {
- set_cpu_active(cpu, true);
+ err = __cpu_notify(CPU_DOWN_PREPARE | mod, hcpu, -1, &nr_calls);
+ if (err) {
nr_calls--;
- __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod,
- hcpu, nr_calls, NULL);
- printk("%s: attempt to take down CPU %u failed\n",
- __func__, cpu);
- err = -EINVAL;
+ __cpu_notify(CPU_DOWN_FAILED | mod, hcpu, nr_calls, NULL);
+ pr_warn("%s: attempt to take down CPU %u failed\n",
+ __func__, cpu);
goto out_release;
}
- /* Ensure that we are not runnable on dying cpu */
- cpumask_copy(old_allowed, &current->cpus_allowed);
- set_cpus_allowed_ptr(current, cpu_active_mask);
+ /*
+ * By now we've cleared cpu_active_mask, wait for all preempt-disabled
+ * and RCU users of this state to go away such that all new such users
+ * will observe it.
+ *
+ * For CONFIG_PREEMPT we have preemptible RCU and its sync_rcu() might
+ * not imply sync_sched(), so explicitly call both.
+ *
+ * Do sync before park smpboot threads to take care the rcu boost case.
+ */
+#ifdef CONFIG_PREEMPT
+ synchronize_sched();
+#endif
+ synchronize_rcu();
+
+ smpboot_park_threads(cpu);
+
+ /*
+ * So now all preempt/rcu users must observe !cpu_active().
+ */
err = __stop_machine(take_cpu_down, &tcd_param, cpumask_of(cpu));
if (err) {
- set_cpu_active(cpu, true);
/* CPU didn't die: tell everyone. Can't complain. */
- if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod,
- hcpu) == NOTIFY_BAD)
- BUG();
-
- goto out_allowed;
+ smpboot_unpark_threads(cpu);
+ cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);
+ goto out_release;
}
BUG_ON(cpu_online(cpu));
- /* Wait for it to sleep (leaving idle task). */
+ /*
+ * The migration_call() CPU_DYING callback will have removed all
+ * runnable tasks from the cpu, there's only the idle task left now
+ * that the migration thread is done doing the stop_machine thing.
+ *
+ * Wait for the stop thread to go away.
+ */
while (!idle_cpu(cpu))
- yield();
+ cpu_relax();
/* This actually kills the CPU. */
__cpu_die(cpu);
/* CPU is completely dead: tell everyone. Too late to complain. */
- if (raw_notifier_call_chain(&cpu_chain, CPU_DEAD | mod,
- hcpu) == NOTIFY_BAD)
- BUG();
+ cpu_notify_nofail(CPU_DEAD | mod, hcpu);
check_for_tasks(cpu);
-out_allowed:
- set_cpus_allowed_ptr(current, old_allowed);
out_release:
cpu_hotplug_done();
- if (!err) {
- if (raw_notifier_call_chain(&cpu_chain, CPU_POST_DEAD | mod,
- hcpu) == NOTIFY_BAD)
- BUG();
- }
- free_cpumask_var(old_allowed);
+ if (!err)
+ cpu_notify_nofail(CPU_POST_DEAD | mod, hcpu);
return err;
}
@@ -271,9 +400,6 @@ int __ref cpu_down(unsigned int cpu)
{
int err;
- err = stop_machine_create();
- if (err)
- return err;
cpu_maps_update_begin();
if (cpu_hotplug_disabled) {
@@ -285,66 +411,82 @@ int __ref cpu_down(unsigned int cpu)
out:
cpu_maps_update_done();
- stop_machine_destroy();
return err;
}
EXPORT_SYMBOL(cpu_down);
#endif /*CONFIG_HOTPLUG_CPU*/
/* Requires cpu_add_remove_lock to be held */
-static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen)
+static int _cpu_up(unsigned int cpu, int tasks_frozen)
{
int ret, nr_calls = 0;
void *hcpu = (void *)(long)cpu;
unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
-
- if (cpu_online(cpu) || !cpu_present(cpu))
- return -EINVAL;
+ struct task_struct *idle;
cpu_hotplug_begin();
- ret = __raw_notifier_call_chain(&cpu_chain, CPU_UP_PREPARE | mod, hcpu,
- -1, &nr_calls);
- if (ret == NOTIFY_BAD) {
- nr_calls--;
- printk("%s: attempt to bring up CPU %u failed\n",
- __func__, cpu);
+
+ if (cpu_online(cpu) || !cpu_present(cpu)) {
ret = -EINVAL;
+ goto out;
+ }
+
+ idle = idle_thread_get(cpu);
+ if (IS_ERR(idle)) {
+ ret = PTR_ERR(idle);
+ goto out;
+ }
+
+ ret = smpboot_create_threads(cpu);
+ if (ret)
+ goto out;
+
+ ret = __cpu_notify(CPU_UP_PREPARE | mod, hcpu, -1, &nr_calls);
+ if (ret) {
+ nr_calls--;
+ pr_warn("%s: attempt to bring up CPU %u failed\n",
+ __func__, cpu);
goto out_notify;
}
/* Arch-specific enabling code. */
- ret = __cpu_up(cpu);
+ ret = __cpu_up(cpu, idle);
if (ret != 0)
goto out_notify;
BUG_ON(!cpu_online(cpu));
- set_cpu_active(cpu, true);
+ /* Wake the per cpu threads */
+ smpboot_unpark_threads(cpu);
/* Now call notifier in preparation. */
- raw_notifier_call_chain(&cpu_chain, CPU_ONLINE | mod, hcpu);
+ cpu_notify(CPU_ONLINE | mod, hcpu);
out_notify:
if (ret != 0)
- __raw_notifier_call_chain(&cpu_chain,
- CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL);
+ __cpu_notify(CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL);
+out:
cpu_hotplug_done();
return ret;
}
-int __cpuinit cpu_up(unsigned int cpu)
+int cpu_up(unsigned int cpu)
{
int err = 0;
+
if (!cpu_possible(cpu)) {
- printk(KERN_ERR "can't online cpu %d because it is not "
- "configured as may-hotadd at boot time\n", cpu);
-#if defined(CONFIG_IA64) || defined(CONFIG_X86_64)
- printk(KERN_ERR "please check additional_cpus= boot "
- "parameter\n");
+ pr_err("can't online cpu %d because it is not configured as may-hotadd at boot time\n",
+ cpu);
+#if defined(CONFIG_IA64)
+ pr_err("please check additional_cpus= boot parameter\n");
#endif
return -EINVAL;
}
+ err = try_online_node(cpu_to_node(cpu));
+ if (err)
+ return err;
+
cpu_maps_update_begin();
if (cpu_hotplug_disabled) {
@@ -358,17 +500,15 @@ out:
cpu_maps_update_done();
return err;
}
+EXPORT_SYMBOL_GPL(cpu_up);
#ifdef CONFIG_PM_SLEEP_SMP
static cpumask_var_t frozen_cpus;
int disable_nonboot_cpus(void)
{
- int cpu, first_cpu, error;
+ int cpu, first_cpu, error = 0;
- error = stop_machine_create();
- if (error)
- return error;
cpu_maps_update_begin();
first_cpu = cpumask_first(cpu_online_mask);
/*
@@ -377,16 +517,17 @@ int disable_nonboot_cpus(void)
*/
cpumask_clear(frozen_cpus);
- printk("Disabling non-boot CPUs ...\n");
+ pr_info("Disabling non-boot CPUs ...\n");
for_each_online_cpu(cpu) {
if (cpu == first_cpu)
continue;
+ trace_suspend_resume(TPS("CPU_OFF"), cpu, true);
error = _cpu_down(cpu, 1);
+ trace_suspend_resume(TPS("CPU_OFF"), cpu, false);
if (!error)
cpumask_set_cpu(cpu, frozen_cpus);
else {
- printk(KERN_ERR "Error taking CPU%d down: %d\n",
- cpu, error);
+ pr_err("Error taking CPU%d down: %d\n", cpu, error);
break;
}
}
@@ -396,10 +537,9 @@ int disable_nonboot_cpus(void)
/* Make sure the CPUs won't be enabled by someone else */
cpu_hotplug_disabled = 1;
} else {
- printk(KERN_ERR "Non-boot CPUs are not disabled\n");
+ pr_err("Non-boot CPUs are not disabled\n");
}
cpu_maps_update_done();
- stop_machine_destroy();
return error;
}
@@ -421,17 +561,19 @@ void __ref enable_nonboot_cpus(void)
if (cpumask_empty(frozen_cpus))
goto out;
- printk("Enabling non-boot CPUs ...\n");
+ pr_info("Enabling non-boot CPUs ...\n");
arch_enable_nonboot_cpus_begin();
for_each_cpu(cpu, frozen_cpus) {
+ trace_suspend_resume(TPS("CPU_ON"), cpu, true);
error = _cpu_up(cpu, 1);
+ trace_suspend_resume(TPS("CPU_ON"), cpu, false);
if (!error) {
- printk("CPU%d is up\n", cpu);
+ pr_info("CPU%d is up\n", cpu);
continue;
}
- printk(KERN_WARNING "Error taking CPU%d up: %d\n", cpu, error);
+ pr_warn("Error taking CPU%d up: %d\n", cpu, error);
}
arch_enable_nonboot_cpus_end();
@@ -441,13 +583,61 @@ out:
cpu_maps_update_done();
}
-static int alloc_frozen_cpus(void)
+static int __init alloc_frozen_cpus(void)
{
if (!alloc_cpumask_var(&frozen_cpus, GFP_KERNEL|__GFP_ZERO))
return -ENOMEM;
return 0;
}
core_initcall(alloc_frozen_cpus);
+
+/*
+ * When callbacks for CPU hotplug notifications are being executed, we must
+ * ensure that the state of the system with respect to the tasks being frozen
+ * or not, as reported by the notification, remains unchanged *throughout the
+ * duration* of the execution of the callbacks.
+ * Hence we need to prevent the freezer from racing with regular CPU hotplug.
+ *
+ * This synchronization is implemented by mutually excluding regular CPU
+ * hotplug and Suspend/Hibernate call paths by hooking onto the Suspend/
+ * Hibernate notifications.
+ */
+static int
+cpu_hotplug_pm_callback(struct notifier_block *nb,
+ unsigned long action, void *ptr)
+{
+ switch (action) {
+
+ case PM_SUSPEND_PREPARE:
+ case PM_HIBERNATION_PREPARE:
+ cpu_hotplug_disable();
+ break;
+
+ case PM_POST_SUSPEND:
+ case PM_POST_HIBERNATION:
+ cpu_hotplug_enable();
+ break;
+
+ default:
+ return NOTIFY_DONE;
+ }
+
+ return NOTIFY_OK;
+}
+
+
+static int __init cpu_hotplug_pm_sync_init(void)
+{
+ /*
+ * cpu_hotplug_pm_callback has higher priority than x86
+ * bsp_pm_callback which depends on cpu_hotplug_pm_callback
+ * to disable cpu hotplug to avoid cpu hotplug race.
+ */
+ pm_notifier(cpu_hotplug_pm_callback, 0);
+ return 0;
+}
+core_initcall(cpu_hotplug_pm_sync_init);
+
#endif /* CONFIG_PM_SLEEP_SMP */
/**
@@ -458,7 +648,7 @@ core_initcall(alloc_frozen_cpus);
* It must be called by the arch code on the new cpu, before the new cpu
* enables interrupts and before the "boot" cpu returns from __cpu_up().
*/
-void __cpuinit notify_cpu_starting(unsigned int cpu)
+void notify_cpu_starting(unsigned int cpu)
{
unsigned long val = CPU_STARTING;
@@ -466,7 +656,7 @@ void __cpuinit notify_cpu_starting(unsigned int cpu)
if (frozen_cpus != NULL && cpumask_test_cpu(cpu, frozen_cpus))
val = CPU_STARTING_FROZEN;
#endif /* CONFIG_PM_SLEEP_SMP */
- raw_notifier_call_chain(&cpu_chain, val, (void *)(long)cpu);
+ cpu_notify(val, (void *)(long)cpu);
}
#endif /* CONFIG_SMP */
@@ -480,7 +670,7 @@ void __cpuinit notify_cpu_starting(unsigned int cpu)
*/
/* cpu_bit_bitmap[0] is empty - so we can back into it */
-#define MASK_DECLARE_1(x) [x+1][0] = 1UL << (x)
+#define MASK_DECLARE_1(x) [x+1][0] = (1UL << (x))
#define MASK_DECLARE_2(x) MASK_DECLARE_1(x), MASK_DECLARE_1(x+1)
#define MASK_DECLARE_4(x) MASK_DECLARE_2(x), MASK_DECLARE_2(x+2)
#define MASK_DECLARE_8(x) MASK_DECLARE_4(x), MASK_DECLARE_4(x+4)
@@ -538,10 +728,12 @@ void set_cpu_present(unsigned int cpu, bool present)
void set_cpu_online(unsigned int cpu, bool online)
{
- if (online)
+ if (online) {
cpumask_set_cpu(cpu, to_cpumask(cpu_online_bits));
- else
+ cpumask_set_cpu(cpu, to_cpumask(cpu_active_bits));
+ } else {
cpumask_clear_cpu(cpu, to_cpumask(cpu_online_bits));
+ }
}
void set_cpu_active(unsigned int cpu, bool active)