diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 5dbdd261aa73..bc96d423781a 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -918,11 +918,19 @@ static struct kobj_type ktype_cpufreq = { .release = cpufreq_sysfs_release, }; -static int add_cpu_dev_symlink(struct cpufreq_policy *policy, - struct device *dev) +static void add_cpu_dev_symlink(struct cpufreq_policy *policy, unsigned int cpu) { + struct device *dev = get_cpu_device(cpu); + + if (!dev) + return; + + if (cpumask_test_and_set_cpu(cpu, policy->real_cpus)) + return; + dev_dbg(dev, "%s: Adding symlink\n", __func__); - return sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq"); + if (sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq")) + dev_err(dev, "cpufreq symlink creation failed\n"); } static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, @@ -1180,10 +1188,10 @@ static int cpufreq_online(unsigned int cpu) policy->user_policy.min = policy->min; policy->user_policy.max = policy->max; - write_lock_irqsave(&cpufreq_driver_lock, flags); - for_each_cpu(j, policy->related_cpus) + for_each_cpu(j, policy->related_cpus) { per_cpu(cpufreq_cpu_data, j) = policy; - write_unlock_irqrestore(&cpufreq_driver_lock, flags); + add_cpu_dev_symlink(policy, j); + } } else { policy->min = policy->user_policy.min; policy->max = policy->user_policy.max; @@ -1275,13 +1283,15 @@ out_exit_policy: if (cpufreq_driver->exit) cpufreq_driver->exit(policy); + + for_each_cpu(j, policy->real_cpus) + remove_cpu_dev_symlink(policy, get_cpu_device(j)); + out_free_policy: cpufreq_policy_free(policy); return ret; } -static int cpufreq_offline(unsigned int cpu); - /** * cpufreq_add_dev - the cpufreq interface for a CPU device. * @dev: CPU device. @@ -1303,16 +1313,10 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) /* Create sysfs link on CPU registration */ policy = per_cpu(cpufreq_cpu_data, cpu); - if (!policy || cpumask_test_and_set_cpu(cpu, policy->real_cpus)) - return 0; + if (policy) + add_cpu_dev_symlink(policy, cpu); - ret = add_cpu_dev_symlink(policy, dev); - if (ret) { - cpumask_clear_cpu(cpu, policy->real_cpus); - cpufreq_offline(cpu); - } - - return ret; + return 0; } static int cpufreq_offline(unsigned int cpu) diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c index 370593006f5f..cda8f62d555b 100644 --- a/drivers/cpuidle/cpuidle-powernv.c +++ b/drivers/cpuidle/cpuidle-powernv.c @@ -175,6 +175,24 @@ static int powernv_cpuidle_driver_init(void) drv->state_count += 1; } + /* + * On the PowerNV platform cpu_present may be less than cpu_possible in + * cases when firmware detects the CPU, but it is not available to the + * OS. If CONFIG_HOTPLUG_CPU=n, then such CPUs are not hotplugable at + * run time and hence cpu_devices are not created for those CPUs by the + * generic topology_init(). + * + * drv->cpumask defaults to cpu_possible_mask in + * __cpuidle_driver_init(). This breaks cpuidle on PowerNV where + * cpu_devices are not created for CPUs in cpu_possible_mask that + * cannot be hot-added later at run time. + * + * Trying cpuidle_register_device() on a CPU without a cpu_device is + * incorrect, so pass a correct CPU mask to the generic cpuidle driver. + */ + + drv->cpumask = (struct cpumask *)cpu_present_mask; + return 0; }