Commit 54d5dcc4 authored by Thomas Renninger's avatar Thomas Renninger Committed by Len Brown
Browse files

ACPI processor hotplug: Split up acpi_processor_add 



No functional change.

This is needed because:
When a CPU gets hotplugged, it's totally uninitialized
and offline. cpuinfo_x86 struct (cpu_data(cpu)) is mostly
zero (CPU feature flags, model, family,..).

When a CPU gets hotplugged, struct processor is alloc'd,
some sysfs files are set up but acpi_processor_add()
must not try to access a MSR on this CPU or try to read
out CPU feature,family, etc.

This must be done in acpi_processor_start().
The next patch will delay the call of acpi_processor_start()
for physically hotpluggedcores, to the time when they are onlined
the first time. There it is safe then to access cpu_data(cpu)
cpuinfo_x86 struct or access MSRs which is needed to
set up cpuidle, throttling and other features.

Tested and
Signed-off-by: default avatarThomas Renninger <trenn@suse.de>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent dcd6c922

drivers/acpi/processor_driver.c

+54 −38
Original line number Diff line number Diff line
@@ -440,6 +440,58 @@ static struct notifier_block acpi_cpu_notifier = 
	    .notifier_call = acpi_cpu_soft_notify,

};



static int __cpuinit acpi_processor_start(struct acpi_processor *pr)

{

	struct acpi_device *device = per_cpu(processor_device_array, pr->id);

	int result = 0;



#ifdef CONFIG_CPU_FREQ

	acpi_processor_ppc_has_changed(pr, 0);

#endif

	acpi_processor_get_throttling_info(pr);

	acpi_processor_get_limit_info(pr);



	if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver)

		acpi_processor_power_init(pr, device);



	pr->cdev = thermal_cooling_device_register("Processor", device,

						   &processor_cooling_ops);

	if (IS_ERR(pr->cdev)) {

		result = PTR_ERR(pr->cdev);

		goto err_power_exit;

	}



	dev_dbg(&device->dev, "registered as cooling_device%d\n",

		pr->cdev->id);



	result = sysfs_create_link(&device->dev.kobj,

				   &pr->cdev->device.kobj,

				   "thermal_cooling");

	if (result) {

		printk(KERN_ERR PREFIX "Create sysfs link\n");

		goto err_thermal_unregister;

	}

	result = sysfs_create_link(&pr->cdev->device.kobj,

				   &device->dev.kobj,

				   "device");

	if (result) {

		printk(KERN_ERR PREFIX "Create sysfs link\n");

		goto err_remove_sysfs_thermal;

	}



	return 0;



err_remove_sysfs_thermal:

	sysfs_remove_link(&device->dev.kobj, "thermal_cooling");

err_thermal_unregister:

	thermal_cooling_device_unregister(pr->cdev);

err_power_exit:

	acpi_processor_power_exit(pr, device);



	return result;

}





static int __cpuinit acpi_processor_add(struct acpi_device *device)

{

	struct acpi_processor *pr = NULL;
@@ -494,49 +546,13 @@ static int __cpuinit acpi_processor_add(struct acpi_device *device) 
		result = -EFAULT;

		goto err_free_cpumask;

	}



#ifdef CONFIG_CPU_FREQ

	acpi_processor_ppc_has_changed(pr, 0);

#endif

	acpi_processor_get_throttling_info(pr);

	acpi_processor_get_limit_info(pr);



	if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver)

		acpi_processor_power_init(pr, device);



	pr->cdev = thermal_cooling_device_register("Processor", device,

						&processor_cooling_ops);

	if (IS_ERR(pr->cdev)) {

		result = PTR_ERR(pr->cdev);

		goto err_power_exit;

	}



	dev_dbg(&device->dev, "registered as cooling_device%d\n",

		 pr->cdev->id);



	result = sysfs_create_link(&device->dev.kobj,

				   &pr->cdev->device.kobj,

				   "thermal_cooling");

	if (result) {

		printk(KERN_ERR PREFIX "Create sysfs link\n");

		goto err_thermal_unregister;

	}

	result = sysfs_create_link(&pr->cdev->device.kobj,

				   &device->dev.kobj,

				   "device");

	if (result) {

		printk(KERN_ERR PREFIX "Create sysfs link\n");

	result = acpi_processor_start(pr);

	if (result)

		goto err_remove_sysfs;

	}



	return 0;



err_remove_sysfs:

	sysfs_remove_link(&device->dev.kobj, "thermal_cooling");

err_thermal_unregister:

	thermal_cooling_device_unregister(pr->cdev);

err_power_exit:

	acpi_processor_power_exit(pr, device);

	sysfs_remove_link(&device->dev.kobj, "sysdev");

err_free_cpumask:

	free_cpumask_var(pr->throttling.shared_cpu_map);

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