#include <linux/stop_machine.h>
#include <linux/mutex.h>
-/*
- * Represents all cpu's present in the system
- * In systems capable of hotplug, this map could dynamically grow
- * as new cpu's are detected in the system via any platform specific
- * method, such as ACPI for e.g.
- */
-cpumask_t cpu_present_map __read_mostly;
-EXPORT_SYMBOL(cpu_present_map);
-
-#ifndef CONFIG_SMP
-
-/*
- * Represents all cpu's that are currently online.
- */
-cpumask_t cpu_online_map __read_mostly = CPU_MASK_ALL;
-EXPORT_SYMBOL(cpu_online_map);
-
-cpumask_t cpu_possible_map __read_mostly = CPU_MASK_ALL;
-EXPORT_SYMBOL(cpu_possible_map);
-
-#else /* CONFIG_SMP */
-
-/* Serializes the updates to cpu_online_map, cpu_present_map */
+#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);
* an ongoing cpu hotplug operation.
*/
int refcount;
-} cpu_hotplug;
-
-void __init cpu_hotplug_init(void)
-{
- cpu_hotplug.active_writer = NULL;
- mutex_init(&cpu_hotplug.lock);
- cpu_hotplug.refcount = 0;
-}
-
-cpumask_t cpu_active_map;
+} cpu_hotplug = {
+ .active_writer = NULL,
+ .lock = __MUTEX_INITIALIZER(cpu_hotplug.lock),
+ .refcount = 0,
+};
#ifdef CONFIG_HOTPLUG_CPU
/*
* The following two API's must be used when attempting
- * to serialize the updates to cpu_online_map, cpu_present_map.
+ * to serialize the updates to cpu_online_mask, cpu_present_mask.
*/
void cpu_maps_update_begin(void)
{
struct take_cpu_down_param *param = _param;
int err;
- raw_notifier_call_chain(&cpu_chain, CPU_DYING | param->mod,
- param->hcpu);
/* Ensure this CPU doesn't handle any more interrupts. */
err = __cpu_disable();
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();
static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
{
int err, nr_calls = 0;
- cpumask_t old_allowed, tmp;
+ 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 = {
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);
+
nr_calls--;
__raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod,
hcpu, nr_calls, NULL);
}
/* Ensure that we are not runnable on dying cpu */
- old_allowed = current->cpus_allowed;
- cpus_setall(tmp);
- cpu_clear(cpu, tmp);
- set_cpus_allowed_ptr(current, &tmp);
+ cpumask_copy(old_allowed, ¤t->cpus_allowed);
+ set_cpus_allowed_ptr(current, cpu_active_mask);
- err = __stop_machine_run(take_cpu_down, &tcd_param, cpu);
+ 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)
check_for_tasks(cpu);
out_allowed:
- set_cpus_allowed_ptr(current, &old_allowed);
+ set_cpus_allowed_ptr(current, old_allowed);
out_release:
cpu_hotplug_done();
if (!err) {
hcpu) == NOTIFY_BAD)
BUG();
}
+ free_cpumask_var(old_allowed);
return err;
}
int __ref cpu_down(unsigned int cpu)
{
- int err = 0;
+ int err;
+ err = stop_machine_create();
+ if (err)
+ return err;
cpu_maps_update_begin();
if (cpu_hotplug_disabled) {
goto out;
}
- cpu_clear(cpu, cpu_active_map);
-
- /*
- * Make sure the all cpus did the reschedule and are not
- * using stale version of the cpu_active_map.
- * This is not strictly necessary becuase stop_machine()
- * that we run down the line already provides the required
- * synchronization. But it's really a side effect and we do not
- * want to depend on the innards of the stop_machine here.
- */
- synchronize_sched();
-
err = _cpu_down(cpu, 0);
- if (cpu_online(cpu))
- cpu_set(cpu, cpu_active_map);
-
out:
cpu_maps_update_done();
+ stop_machine_destroy();
return err;
}
EXPORT_SYMBOL(cpu_down);
goto out_notify;
BUG_ON(!cpu_online(cpu));
+ set_cpu_active(cpu, true);
+
/* Now call notifier in preparation. */
raw_notifier_call_chain(&cpu_chain, CPU_ONLINE | mod, hcpu);
int __cpuinit cpu_up(unsigned int cpu)
{
int err = 0;
- if (!cpu_isset(cpu, cpu_possible_map)) {
+ 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) || defined(CONFIG_S390)
+#if defined(CONFIG_IA64) || defined(CONFIG_X86_64)
printk(KERN_ERR "please check additional_cpus= boot "
"parameter\n");
#endif
err = _cpu_up(cpu, 0);
- if (cpu_online(cpu))
- cpu_set(cpu, cpu_active_map);
-
out:
cpu_maps_update_done();
return err;
}
#ifdef CONFIG_PM_SLEEP_SMP
-static cpumask_t frozen_cpus;
+static cpumask_var_t frozen_cpus;
int disable_nonboot_cpus(void)
{
- int cpu, first_cpu, error = 0;
+ int cpu, first_cpu, error;
+ error = stop_machine_create();
+ if (error)
+ return error;
cpu_maps_update_begin();
- first_cpu = first_cpu(cpu_online_map);
- /* We take down all of the non-boot CPUs in one shot to avoid races
+ first_cpu = cpumask_first(cpu_online_mask);
+ /*
+ * We take down all of the non-boot CPUs in one shot to avoid races
* with the userspace trying to use the CPU hotplug at the same time
*/
- cpus_clear(frozen_cpus);
+ cpumask_clear(frozen_cpus);
+
printk("Disabling non-boot CPUs ...\n");
for_each_online_cpu(cpu) {
if (cpu == first_cpu)
continue;
error = _cpu_down(cpu, 1);
- if (!error) {
- cpu_set(cpu, frozen_cpus);
- printk("CPU%d is down\n", cpu);
- } else {
+ if (!error)
+ cpumask_set_cpu(cpu, frozen_cpus);
+ else {
printk(KERN_ERR "Error taking CPU%d down: %d\n",
cpu, error);
break;
}
}
+
if (!error) {
BUG_ON(num_online_cpus() > 1);
/* Make sure the CPUs won't be enabled by someone else */
printk(KERN_ERR "Non-boot CPUs are not disabled\n");
}
cpu_maps_update_done();
+ stop_machine_destroy();
return error;
}
+void __weak arch_enable_nonboot_cpus_begin(void)
+{
+}
+
+void __weak arch_enable_nonboot_cpus_end(void)
+{
+}
+
void __ref enable_nonboot_cpus(void)
{
int cpu, error;
/* Allow everyone to use the CPU hotplug again */
cpu_maps_update_begin();
cpu_hotplug_disabled = 0;
- if (cpus_empty(frozen_cpus))
+ if (cpumask_empty(frozen_cpus))
goto out;
printk("Enabling non-boot CPUs ...\n");
- for_each_cpu_mask_nr(cpu, frozen_cpus) {
+
+ arch_enable_nonboot_cpus_begin();
+
+ for_each_cpu(cpu, frozen_cpus) {
error = _cpu_up(cpu, 1);
if (!error) {
printk("CPU%d is up\n", cpu);
}
printk(KERN_WARNING "Error taking CPU%d up: %d\n", cpu, error);
}
- cpus_clear(frozen_cpus);
+
+ arch_enable_nonboot_cpus_end();
+
+ cpumask_clear(frozen_cpus);
out:
cpu_maps_update_done();
}
+
+static int alloc_frozen_cpus(void)
+{
+ if (!alloc_cpumask_var(&frozen_cpus, GFP_KERNEL|__GFP_ZERO))
+ return -ENOMEM;
+ return 0;
+}
+core_initcall(alloc_frozen_cpus);
+#endif /* CONFIG_PM_SLEEP_SMP */
+
+/**
+ * notify_cpu_starting(cpu) - call the CPU_STARTING notifiers
+ * @cpu: cpu that just started
+ *
+ * This function calls the cpu_chain notifiers with CPU_STARTING.
+ * 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)
+{
+ unsigned long val = CPU_STARTING;
+
+#ifdef CONFIG_PM_SLEEP_SMP
+ 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);
+}
#endif /* CONFIG_SMP */
+
+/*
+ * cpu_bit_bitmap[] is a special, "compressed" data structure that
+ * represents all NR_CPUS bits binary values of 1<<nr.
+ *
+ * It is used by cpumask_of() to get a constant address to a CPU
+ * mask value that has a single bit set only.
+ */
+
+/* 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_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)
+
+const unsigned long cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)] = {
+
+ MASK_DECLARE_8(0), MASK_DECLARE_8(8),
+ MASK_DECLARE_8(16), MASK_DECLARE_8(24),
+#if BITS_PER_LONG > 32
+ MASK_DECLARE_8(32), MASK_DECLARE_8(40),
+ MASK_DECLARE_8(48), MASK_DECLARE_8(56),
+#endif
+};
+EXPORT_SYMBOL_GPL(cpu_bit_bitmap);
+
+const DECLARE_BITMAP(cpu_all_bits, NR_CPUS) = CPU_BITS_ALL;
+EXPORT_SYMBOL(cpu_all_bits);
+
+#ifdef CONFIG_INIT_ALL_POSSIBLE
+static DECLARE_BITMAP(cpu_possible_bits, CONFIG_NR_CPUS) __read_mostly
+ = CPU_BITS_ALL;
+#else
+static DECLARE_BITMAP(cpu_possible_bits, CONFIG_NR_CPUS) __read_mostly;
+#endif
+const struct cpumask *const cpu_possible_mask = to_cpumask(cpu_possible_bits);
+EXPORT_SYMBOL(cpu_possible_mask);
+
+static DECLARE_BITMAP(cpu_online_bits, CONFIG_NR_CPUS) __read_mostly;
+const struct cpumask *const cpu_online_mask = to_cpumask(cpu_online_bits);
+EXPORT_SYMBOL(cpu_online_mask);
+
+static DECLARE_BITMAP(cpu_present_bits, CONFIG_NR_CPUS) __read_mostly;
+const struct cpumask *const cpu_present_mask = to_cpumask(cpu_present_bits);
+EXPORT_SYMBOL(cpu_present_mask);
+
+static DECLARE_BITMAP(cpu_active_bits, CONFIG_NR_CPUS) __read_mostly;
+const struct cpumask *const cpu_active_mask = to_cpumask(cpu_active_bits);
+EXPORT_SYMBOL(cpu_active_mask);
+
+void set_cpu_possible(unsigned int cpu, bool possible)
+{
+ if (possible)
+ cpumask_set_cpu(cpu, to_cpumask(cpu_possible_bits));
+ else
+ cpumask_clear_cpu(cpu, to_cpumask(cpu_possible_bits));
+}
+
+void set_cpu_present(unsigned int cpu, bool present)
+{
+ if (present)
+ cpumask_set_cpu(cpu, to_cpumask(cpu_present_bits));
+ else
+ cpumask_clear_cpu(cpu, to_cpumask(cpu_present_bits));
+}
+
+void set_cpu_online(unsigned int cpu, bool online)
+{
+ if (online)
+ cpumask_set_cpu(cpu, to_cpumask(cpu_online_bits));
+ else
+ cpumask_clear_cpu(cpu, to_cpumask(cpu_online_bits));
+}
+
+void set_cpu_active(unsigned int cpu, bool active)
+{
+ if (active)
+ cpumask_set_cpu(cpu, to_cpumask(cpu_active_bits));
+ else
+ cpumask_clear_cpu(cpu, to_cpumask(cpu_active_bits));
+}
+
+void init_cpu_present(const struct cpumask *src)
+{
+ cpumask_copy(to_cpumask(cpu_present_bits), src);
+}
+
+void init_cpu_possible(const struct cpumask *src)
+{
+ cpumask_copy(to_cpumask(cpu_possible_bits), src);
+}
+
+void init_cpu_online(const struct cpumask *src)
+{
+ cpumask_copy(to_cpumask(cpu_online_bits), src);
+}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff