ACPI: Add ACPI CPU hot-remove support

Added support of CPU hot-remove via an ACPI eject notification.
It calls acpi_bus_hot_remove_device(), which shares the same code
path with the sysfs eject operation.  acpi_os_hotplug_execute()
runs the hot-remove operation in kacpi_hotplug_wq and serializes
it between ACPI hot-remove and sysfs eject requests.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Tested-by: IgorMammedov <imammedo@redhat.com>
Tested-by: Vijay Mohan Pandarathil <vijaymohan.pandarathil@hp.com>
Tested-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
index a4352b8..8cc33d0 100644 (file)
--- a/drivers/acpi/processor_driver.c
+++ b/drivers/acpi/processor_driver.c
@@ -695,8 +695,8 @@ int acpi_processor_device_add(acpi_handle handle, struct acpi_device **device)
 static void acpi_processor_hotplug_notify(acpi_handle handle,
                                          u32 event, void *data)
 {
-       struct acpi_processor *pr;
        struct acpi_device *device = NULL;
+       struct acpi_eject_event *ej_event = NULL;
        u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */
        int result;
 
@@ -728,20 +728,27 @@ static void acpi_processor_hotplug_notify(acpi_handle handle,
                                  "received ACPI_NOTIFY_EJECT_REQUEST\n"));
 
                if (acpi_bus_get_device(handle, &device)) {
-                       printk(KERN_ERR PREFIX
-                                   "Device don't exist, dropping EJECT\n");
+                       pr_err(PREFIX "Device don't exist, dropping EJECT\n");
                        break;
                }
-               pr = acpi_driver_data(device);
-               if (!pr) {
-                       printk(KERN_ERR PREFIX
-                                   "Driver data is NULL, dropping EJECT\n");
+               if (!acpi_driver_data(device)) {
+                       pr_err(PREFIX "Driver data is NULL, dropping EJECT\n");
                        break;
                }
 
-               /* REVISIT: update when eject is supported */
-               ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
-               break;
+               ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
+               if (!ej_event) {
+                       pr_err(PREFIX "No memory, dropping EJECT\n");
+                       break;
+               }
+
+               ej_event->handle = handle;
+               ej_event->event = ACPI_NOTIFY_EJECT_REQUEST;
+               acpi_os_hotplug_execute(acpi_bus_hot_remove_device,
+                                       (void *)ej_event);
+
+               /* eject is performed asynchronously */
+               return;
 
        default:
                ACPI_DEBUG_PRINT((ACPI_DB_INFO,