1 files changed, 114 insertions, 40 deletions

diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
index 0034ede38710..2b805d7ef317 100644
--- a/drivers/acpi/processor_driver.c
+++ b/drivers/acpi/processor_driver.c
@@ -84,7 +84,7 @@ static int acpi_processor_remove(struct acpi_device *device, int type);
 static void acpi_processor_notify(struct acpi_device *device, u32 event);
 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr);
 static int acpi_processor_handle_eject(struct acpi_processor *pr);
-
+static int acpi_processor_start(struct acpi_processor *pr);
 
 static const struct acpi_device_id processor_device_ids[] = {
         {ACPI_PROCESSOR_OBJECT_HID, 0},
@@ -423,10 +423,29 @@ static int acpi_cpu_soft_notify(struct notifier_block *nfb,
         struct acpi_processor *pr = per_cpu(processors, cpu);
 
         if (action == CPU_ONLINE && pr) {
-                acpi_processor_ppc_has_changed(pr, 0);
-                acpi_processor_hotplug(pr);
-                acpi_processor_reevaluate_tstate(pr, action);
-                acpi_processor_tstate_has_changed(pr);
+                /* CPU got physically hotplugged and onlined the first time:
+                 * Initialize missing things
+                 */
+                if (pr->flags.need_hotplug_init) {
+                        struct cpuidle_driver *idle_driver =
+                                cpuidle_get_driver();
+
+                        printk(KERN_INFO "Will online and init hotplugged "
+                               "CPU: %d\n", pr->id);
+                        WARN(acpi_processor_start(pr), "Failed to start CPU:"
+                                " %d\n", pr->id);
+                        pr->flags.need_hotplug_init = 0;
+                        if (idle_driver && !strcmp(idle_driver->name,
+                                                   "intel_idle")) {
+                                intel_idle_cpu_init(pr->id);
+                        }
+                /* Normal CPU soft online event */
+                } else {
+                        acpi_processor_ppc_has_changed(pr, 0);
+                        acpi_processor_cst_has_changed(pr);
+                        acpi_processor_reevaluate_tstate(pr, action);
+                        acpi_processor_tstate_has_changed(pr);
+                }
         }
         if (action == CPU_DEAD && pr) {
                 /* invalidate the flag.throttling after one CPU is offline */
@@ -440,6 +459,71 @@ static struct notifier_block acpi_cpu_notifier =
             .notifier_call = acpi_cpu_soft_notify,
 };
 
+/*
+ * acpi_processor_start() is called by the cpu_hotplug_notifier func:
+ * acpi_cpu_soft_notify(). Getting it __cpuinit{data} is difficult, the
+ * root cause seem to be that acpi_processor_uninstall_hotplug_notify()
+ * is in the module_exit (__exit) func. Allowing acpi_processor_start()
+ * to not be in __cpuinit section, but being called from __cpuinit funcs
+ * via __ref looks like the right thing to do here.
+ */
+static __ref int 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;
+}
+
+/*
+ * Do not put anything in here which needs the core to be online.
+ * For example MSR access or setting up things which check for cpuinfo_x86
+ * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
+ * Such things have to be put in and set up above in acpi_processor_start()
+ */
 static int __cpuinit acpi_processor_add(struct acpi_device *device)
 {
         struct acpi_processor *pr = NULL;
@@ -495,48 +579,27 @@ static int __cpuinit acpi_processor_add(struct acpi_device *device)
                 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;
-        }
+        /*
+         * Do not start hotplugged CPUs now, but when they
+         * are onlined the first time
+         */
+        if (pr->flags.need_hotplug_init)
+                return 0;
 
-        dev_dbg(&device->dev, "registered as cooling_device%d\n",
-                 pr->cdev->id);
+        /*
+         * Do not start hotplugged CPUs now, but when they
+         * are onlined the first time
+         */
+        if (pr->flags.need_hotplug_init)
+                return 0;
 
-        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);
@@ -735,6 +798,17 @@ static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
                 return AE_ERROR;
         }
 
+        /* CPU got hot-plugged, but cpu_data is not initialized yet
+         * Set flag to delay cpu_idle/throttling initialization
+         * in:
+         * acpi_processor_add()
+         *   acpi_processor_get_info()
+         * and do it when the CPU gets online the first time
+         * TBD: Cleanup above functions and try to do this more elegant.
+         */
+        printk(KERN_INFO "CPU %d got hotplugged\n", pr->id);
+        pr->flags.need_hotplug_init = 1;
+
         return AE_OK;
 }