Re: [PATCH v2] ACPI: Add CPU hotplug support for processor device objects

[Len Brown <lenb@kernel.org>]

Tested on what?

thanks,
-Len

On 03/20/2012 07:58 PM, Toshi Kani wrote:

> acpi_processor_install_hotplug_notify() registers processor objects to
> receive ACPI CPU hotplug event notifications. This patch additionally
> registers processor device objects (ACPI0007) to receive the notifications
> as well.
> 
> v2: Changed is_processor_device() to a boolean func.
> 
> Signed-off-by: Toshi Kani <toshi.kani@hp.com>
> Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
> ---
>  drivers/acpi/processor_driver.c |   54 ++++++++++++++++++++++++++++++--------
>  1 files changed, 42 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
> index 8ae05ce..71bdaf1 100644
> --- a/drivers/acpi/processor_driver.c
> +++ b/drivers/acpi/processor_driver.c
> @@ -68,6 +68,7 @@
>  #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
>  #define ACPI_PROCESSOR_NOTIFY_POWER	0x81
>  #define ACPI_PROCESSOR_NOTIFY_THROTTLING	0x82
> +#define ACPI_PROCESSOR_DEVICE_HID	"ACPI0007"
>  
>  #define ACPI_PROCESSOR_LIMIT_USER	0
>  #define ACPI_PROCESSOR_LIMIT_THERMAL	1
> @@ -88,7 +89,7 @@ static int acpi_processor_start(struct acpi_processor *pr);
>  
>  static const struct acpi_device_id processor_device_ids[] = {
>  	{ACPI_PROCESSOR_OBJECT_HID, 0},
> -	{"ACPI0007", 0},
> +	{ACPI_PROCESSOR_DEVICE_HID, 0},
>  	{"", 0},
>  };
>  MODULE_DEVICE_TABLE(acpi, processor_device_ids);
> @@ -741,20 +742,48 @@ static void acpi_processor_hotplug_notify(acpi_handle handle,
>  	return;
>  }
>  
> +static bool is_processor_device(acpi_handle handle)
> +{
> +	struct acpi_device_info *info;
> +	char *hid;
> +	acpi_status status;
> +	bool is_proc;
> +
> +	status = acpi_get_object_info(handle, &info);
> +	if (ACPI_FAILURE(status))
> +		return false;
> +
> +	if (info->type == ACPI_TYPE_PROCESSOR) {
> +		is_proc = true;	/* found a processor object */
> +		goto cleanup;
> +	}
> +
> +	if (!(info->valid & ACPI_VALID_HID)) {
> +		is_proc = false;
> +		goto cleanup;
> +	}
> +
> +	hid = info->hardware_id.string;
> +	if ((hid == NULL) || strcmp(hid, ACPI_PROCESSOR_DEVICE_HID)) {
> +		is_proc = false;
> +		goto cleanup;
> +	}
> +
> +	is_proc = true;		/* found a processor device object */
> +
> +cleanup:
> +	kfree(info);
> +	return is_proc;
> +}
> +
>  static acpi_status
>  processor_walk_namespace_cb(acpi_handle handle,
>  			    u32 lvl, void *context, void **rv)
>  {
> -	acpi_status status;
>  	int *action = context;
> -	acpi_object_type type = 0;
> -
> -	status = acpi_get_type(handle, &type);
> -	if (ACPI_FAILURE(status))
> -		return (AE_OK);
>  
> -	if (type != ACPI_TYPE_PROCESSOR)
> -		return (AE_OK);
> +	if (!is_processor_device(handle))
> +		return AE_OK;	/* not a processor; continue to walk */
>  
>  	switch (*action) {
>  	case INSTALL_NOTIFY_HANDLER:
> @@ -772,7 +801,8 @@ processor_walk_namespace_cb(acpi_handle handle,
>  		break;
>  	}
>  
> -	return (AE_OK);
> +	/* found a processor; skip walking underneath */
> +	return AE_CTRL_DEPTH;
>  }
>  
>  static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
> @@ -830,7 +860,7 @@ void acpi_processor_install_hotplug_notify(void)
>  {
>  #ifdef CONFIG_ACPI_HOTPLUG_CPU
>  	int action = INSTALL_NOTIFY_HANDLER;
> -	acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
> +	acpi_walk_namespace(ACPI_TYPE_ANY,
>  			    ACPI_ROOT_OBJECT,
>  			    ACPI_UINT32_MAX,
>  			    processor_walk_namespace_cb, NULL, &action, NULL);
> @@ -843,7 +873,7 @@ void acpi_processor_uninstall_hotplug_notify(void)
>  {
>  #ifdef CONFIG_ACPI_HOTPLUG_CPU
>  	int action = UNINSTALL_NOTIFY_HANDLER;
> -	acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
> +	acpi_walk_namespace(ACPI_TYPE_ANY,
>  			    ACPI_ROOT_OBJECT,
>  			    ACPI_UINT32_MAX,
>  			    processor_walk_namespace_cb, NULL, &action, NULL);