*
* This code is licenced under the GPL.
*/
+#include <linux/sched/mm.h>
#include <linux/proc_fs.h>
#include <linux/smp.h>
#include <linux/init.h>
static void lockdep_acquire_cpus_lock(void)
{
- rwsem_acquire(&cpu_hotplug_lock.rw_sem.dep_map, 0, 0, _THIS_IP_);
+ rwsem_acquire(&cpu_hotplug_lock.dep_map, 0, 0, _THIS_IP_);
}
static void lockdep_release_cpus_lock(void)
{
- rwsem_release(&cpu_hotplug_lock.rw_sem.dep_map, _THIS_IP_);
+ rwsem_release(&cpu_hotplug_lock.dep_map, _THIS_IP_);
}
/*
/*
* On x86 it's required to boot all logical CPUs at least once so
* that the init code can get a chance to set CR4.MCE on each
- * CPU. Otherwise, a broadacasted MCE observing CR4.MCE=0b on any
+ * CPU. Otherwise, a broadcasted MCE observing CR4.MCE=0b on any
* core will shutdown the machine.
*/
return !cpumask_test_cpu(cpu, &cpus_booted_once_mask);
return bringup_wait_for_ap(cpu);
}
+static int finish_cpu(unsigned int cpu)
+{
+ struct task_struct *idle = idle_thread_get(cpu);
+ struct mm_struct *mm = idle->active_mm;
+
+ /*
+ * idle_task_exit() will have switched to &init_mm, now
+ * clean up any remaining active_mm state.
+ */
+ if (mm != &init_mm)
+ idle->active_mm = &init_mm;
+ mmdrop(mm);
+ return 0;
+}
+
/*
* Hotplug state machine related functions
*/
return _cpu_down(cpu, 0, target);
}
-static int do_cpu_down(unsigned int cpu, enum cpuhp_state target)
+static int cpu_down(unsigned int cpu, enum cpuhp_state target)
{
int err;
return err;
}
-int cpu_down(unsigned int cpu)
+/**
+ * cpu_device_down - Bring down a cpu device
+ * @dev: Pointer to the cpu device to offline
+ *
+ * This function is meant to be used by device core cpu subsystem only.
+ *
+ * Other subsystems should use remove_cpu() instead.
+ */
+int cpu_device_down(struct device *dev)
+{
+ return cpu_down(dev->id, CPUHP_OFFLINE);
+}
+
+int remove_cpu(unsigned int cpu)
{
- return do_cpu_down(cpu, CPUHP_OFFLINE);
+ int ret;
+
+ lock_device_hotplug();
+ ret = device_offline(get_cpu_device(cpu));
+ unlock_device_hotplug();
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(remove_cpu);
+
+void smp_shutdown_nonboot_cpus(unsigned int primary_cpu)
+{
+ unsigned int cpu;
+ int error;
+
+ cpu_maps_update_begin();
+
+ /*
+ * Make certain the cpu I'm about to reboot on is online.
+ *
+ * This is inline to what migrate_to_reboot_cpu() already do.
+ */
+ if (!cpu_online(primary_cpu))
+ primary_cpu = cpumask_first(cpu_online_mask);
+
+ for_each_online_cpu(cpu) {
+ if (cpu == primary_cpu)
+ continue;
+
+ error = cpu_down_maps_locked(cpu, CPUHP_OFFLINE);
+ if (error) {
+ pr_err("Failed to offline CPU%d - error=%d",
+ cpu, error);
+ break;
+ }
+ }
+
+ /*
+ * Ensure all but the reboot CPU are offline.
+ */
+ BUG_ON(num_online_cpus() > 1);
+
+ /*
+ * Make sure the CPUs won't be enabled by someone else after this
+ * point. Kexec will reboot to a new kernel shortly resetting
+ * everything along the way.
+ */
+ cpu_hotplug_disabled++;
+
+ cpu_maps_update_done();
}
-EXPORT_SYMBOL(cpu_down);
#else
#define takedown_cpu NULL
}
/*
- * The caller of do_cpu_up might have raced with another
- * caller. Ignore it for now.
+ * The caller of cpu_up() might have raced with another
+ * caller. Nothing to do.
*/
if (st->state >= target)
goto out;
return ret;
}
-static int do_cpu_up(unsigned int cpu, enum cpuhp_state target)
+static int cpu_up(unsigned int cpu, enum cpuhp_state target)
{
int err = 0;
return err;
}
-int cpu_up(unsigned int cpu)
+/**
+ * cpu_device_up - Bring up a cpu device
+ * @dev: Pointer to the cpu device to online
+ *
+ * This function is meant to be used by device core cpu subsystem only.
+ *
+ * Other subsystems should use add_cpu() instead.
+ */
+int cpu_device_up(struct device *dev)
+{
+ return cpu_up(dev->id, CPUHP_ONLINE);
+}
+
+int add_cpu(unsigned int cpu)
{
- return do_cpu_up(cpu, CPUHP_ONLINE);
+ int ret;
+
+ lock_device_hotplug();
+ ret = device_online(get_cpu_device(cpu));
+ unlock_device_hotplug();
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(add_cpu);
+
+/**
+ * bringup_hibernate_cpu - Bring up the CPU that we hibernated on
+ * @sleep_cpu: The cpu we hibernated on and should be brought up.
+ *
+ * On some architectures like arm64, we can hibernate on any CPU, but on
+ * wake up the CPU we hibernated on might be offline as a side effect of
+ * using maxcpus= for example.
+ */
+int bringup_hibernate_cpu(unsigned int sleep_cpu)
+{
+ int ret;
+
+ if (!cpu_online(sleep_cpu)) {
+ pr_info("Hibernated on a CPU that is offline! Bringing CPU up.\n");
+ ret = cpu_up(sleep_cpu, CPUHP_ONLINE);
+ if (ret) {
+ pr_err("Failed to bring hibernate-CPU up!\n");
+ return ret;
+ }
+ }
+ return 0;
+}
+
+void bringup_nonboot_cpus(unsigned int setup_max_cpus)
+{
+ unsigned int cpu;
+
+ for_each_present_cpu(cpu) {
+ if (num_online_cpus() >= setup_max_cpus)
+ break;
+ if (!cpu_online(cpu))
+ cpu_up(cpu, CPUHP_ONLINE);
+ }
}
-EXPORT_SYMBOL_GPL(cpu_up);
#ifdef CONFIG_PM_SLEEP_SMP
static cpumask_var_t frozen_cpus;
/*
* Make sure the CPUs won't be enabled by someone else. We need to do
- * this even in case of failure as all disable_nonboot_cpus() users are
- * supposed to do enable_nonboot_cpus() on the failure path.
+ * this even in case of failure as all freeze_secondary_cpus() users are
+ * supposed to do thaw_secondary_cpus() on the failure path.
*/
cpu_hotplug_disabled++;
return error;
}
-void __weak arch_enable_nonboot_cpus_begin(void)
+void __weak arch_thaw_secondary_cpus_begin(void)
{
}
-void __weak arch_enable_nonboot_cpus_end(void)
+void __weak arch_thaw_secondary_cpus_end(void)
{
}
-void enable_nonboot_cpus(void)
+void thaw_secondary_cpus(void)
{
int cpu, error;
pr_info("Enabling non-boot CPUs ...\n");
- arch_enable_nonboot_cpus_begin();
+ arch_thaw_secondary_cpus_begin();
for_each_cpu(cpu, frozen_cpus) {
trace_suspend_resume(TPS("CPU_ON"), cpu, true);
pr_warn("Error taking CPU%d up: %d\n", cpu, error);
}
- arch_enable_nonboot_cpus_end();
+ arch_thaw_secondary_cpus_end();
cpumask_clear(frozen_cpus);
out:
[CPUHP_BRINGUP_CPU] = {
.name = "cpu:bringup",
.startup.single = bringup_cpu,
- .teardown.single = NULL,
+ .teardown.single = finish_cpu,
.cant_stop = true,
},
/* Final state before CPU kills itself */
goto out;
if (st->state < target)
- ret = do_cpu_up(dev->id, target);
+ ret = cpu_up(dev->id, target);
else
- ret = do_cpu_down(dev->id, target);
+ ret = cpu_down(dev->id, target);
out:
unlock_device_hotplug();
return ret ? ret : count;
projects / linux-2.6-microblaze.git / blobdiff