diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 26063afb3eba..7a3c30c4336f 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -1002,7 +1002,7 @@ static int cpufreq_add_dev_symlink(struct cpufreq_policy *policy) int ret = 0; /* Some related CPUs might not be present (physically hotplugged) */ - for_each_cpu_and(j, policy->related_cpus, cpu_present_mask) { + for_each_cpu(j, policy->real_cpus) { if (j == policy->kobj_cpu) continue; @@ -1019,7 +1019,7 @@ static void cpufreq_remove_dev_symlink(struct cpufreq_policy *policy) unsigned int j; /* Some related CPUs might not be present (physically hotplugged) */ - for_each_cpu_and(j, policy->related_cpus, cpu_present_mask) { + for_each_cpu(j, policy->real_cpus) { if (j == policy->kobj_cpu) continue; @@ -1163,11 +1163,14 @@ static struct cpufreq_policy *cpufreq_policy_alloc(struct device *dev) if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) goto err_free_cpumask; + if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) + goto err_free_rcpumask; + ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, &dev->kobj, "cpufreq"); if (ret) { pr_err("%s: failed to init policy->kobj: %d\n", __func__, ret); - goto err_free_rcpumask; + goto err_free_real_cpus; } INIT_LIST_HEAD(&policy->policy_list); @@ -1184,6 +1187,8 @@ static struct cpufreq_policy *cpufreq_policy_alloc(struct device *dev) return policy; +err_free_real_cpus: + free_cpumask_var(policy->real_cpus); err_free_rcpumask: free_cpumask_var(policy->related_cpus); err_free_cpumask: @@ -1234,6 +1239,7 @@ static void cpufreq_policy_free(struct cpufreq_policy *policy, bool notify) write_unlock_irqrestore(&cpufreq_driver_lock, flags); cpufreq_policy_put_kobj(policy, notify); + free_cpumask_var(policy->real_cpus); free_cpumask_var(policy->related_cpus); free_cpumask_var(policy->cpus); kfree(policy); @@ -1258,14 +1264,17 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) pr_debug("adding CPU %u\n", cpu); - /* - * Only possible if 'cpu' wasn't physically present earlier and we are - * here from subsys_interface add callback. A hotplug notifier will - * follow and we will handle it like logical CPU hotplug then. For now, - * just create the sysfs link. - */ - if (cpu_is_offline(cpu)) - return add_cpu_dev_symlink(per_cpu(cpufreq_cpu_data, cpu), cpu); + if (cpu_is_offline(cpu)) { + /* + * Only possible if we are here from the subsys_interface add + * callback. A hotplug notifier will follow and we will handle + * it as CPU online then. For now, just create the sysfs link, + * unless there is no policy or the link is already present. + */ + policy = per_cpu(cpufreq_cpu_data, cpu); + return policy && !cpumask_test_and_set_cpu(cpu, policy->real_cpus) + ? add_cpu_dev_symlink(policy, cpu) : 0; + } if (!down_read_trylock(&cpufreq_rwsem)) return 0; @@ -1307,6 +1316,10 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) /* related cpus should atleast have policy->cpus */ cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus); + /* Remember which CPUs have been present at the policy creation time. */ + if (!recover_policy) + cpumask_and(policy->real_cpus, policy->cpus, cpu_present_mask); + /* * affected cpus must always be the one, which are online. We aren't * managing offline cpus here. @@ -1420,8 +1433,7 @@ nomem_out: return ret; } -static int __cpufreq_remove_dev_prepare(struct device *dev, - struct subsys_interface *sif) +static int __cpufreq_remove_dev_prepare(struct device *dev) { unsigned int cpu = dev->id; int ret = 0; @@ -1437,10 +1449,8 @@ static int __cpufreq_remove_dev_prepare(struct device *dev, if (has_target()) { ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP); - if (ret) { + if (ret) pr_err("%s: Failed to stop governor\n", __func__); - return ret; - } } down_write(&policy->rwsem); @@ -1473,8 +1483,7 @@ static int __cpufreq_remove_dev_prepare(struct device *dev, return ret; } -static int __cpufreq_remove_dev_finish(struct device *dev, - struct subsys_interface *sif) +static int __cpufreq_remove_dev_finish(struct device *dev) { unsigned int cpu = dev->id; int ret; @@ -1492,10 +1501,8 @@ static int __cpufreq_remove_dev_finish(struct device *dev, /* If cpu is last user of policy, free policy */ if (has_target()) { ret = __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); - if (ret) { + if (ret) pr_err("%s: Failed to exit governor\n", __func__); - return ret; - } } /* @@ -1506,10 +1513,6 @@ static int __cpufreq_remove_dev_finish(struct device *dev, if (cpufreq_driver->exit) cpufreq_driver->exit(policy); - /* Free the policy only if the driver is getting removed. */ - if (sif) - cpufreq_policy_free(policy, true); - return 0; } @@ -1521,42 +1524,41 @@ static int __cpufreq_remove_dev_finish(struct device *dev, static int cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) { unsigned int cpu = dev->id; - int ret; + struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); - /* - * Only possible if 'cpu' is getting physically removed now. A hotplug - * notifier should have already been called and we just need to remove - * link or free policy here. - */ - if (cpu_is_offline(cpu)) { - struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); - struct cpumask mask; + if (!policy) + return 0; - if (!policy) - return 0; + if (cpu_online(cpu)) { + __cpufreq_remove_dev_prepare(dev); + __cpufreq_remove_dev_finish(dev); + } - cpumask_copy(&mask, policy->related_cpus); - cpumask_clear_cpu(cpu, &mask); - - /* - * Free policy only if all policy->related_cpus are removed - * physically. - */ - if (cpumask_intersects(&mask, cpu_present_mask)) { - remove_cpu_dev_symlink(policy, cpu); - return 0; - } + cpumask_clear_cpu(cpu, policy->real_cpus); + if (cpumask_empty(policy->real_cpus)) { cpufreq_policy_free(policy, true); return 0; } - ret = __cpufreq_remove_dev_prepare(dev, sif); + if (cpu != policy->kobj_cpu) { + remove_cpu_dev_symlink(policy, cpu); + } else { + /* + * The CPU owning the policy object is going away. Move it to + * another suitable CPU. + */ + unsigned int new_cpu = cpumask_first(policy->real_cpus); + struct device *new_dev = get_cpu_device(new_cpu); - if (!ret) - ret = __cpufreq_remove_dev_finish(dev, sif); + dev_dbg(dev, "%s: Moving policy object to CPU%u\n", __func__, new_cpu); - return ret; + sysfs_remove_link(&new_dev->kobj, "cpufreq"); + policy->kobj_cpu = new_cpu; + WARN_ON(kobject_move(&policy->kobj, &new_dev->kobj)); + } + + return 0; } static void handle_update(struct work_struct *work) @@ -2395,11 +2397,11 @@ static int cpufreq_cpu_callback(struct notifier_block *nfb, break; case CPU_DOWN_PREPARE: - __cpufreq_remove_dev_prepare(dev, NULL); + __cpufreq_remove_dev_prepare(dev); break; case CPU_POST_DEAD: - __cpufreq_remove_dev_finish(dev, NULL); + __cpufreq_remove_dev_finish(dev); break; case CPU_DOWN_FAILED: diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 29ad97c34fd5..bde1e567b3a9 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -62,6 +62,7 @@ struct cpufreq_policy { /* CPUs sharing clock, require sw coordination */ cpumask_var_t cpus; /* Online CPUs only */ cpumask_var_t related_cpus; /* Online + Offline CPUs */ + cpumask_var_t real_cpus; /* Related and present */ unsigned int shared_type; /* ACPI: ANY or ALL affected CPUs should set cpufreq */