diff options
| -rw-r--r-- | drivers/cpufreq/cpufreq.c | 153 |
1 files changed, 55 insertions, 98 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 9af14a8bbcdb..5f72ad486746 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -703,92 +703,6 @@ static struct kobj_type ktype_cpufreq = { .release = cpufreq_sysfs_release, }; -/* - * Returns: - * Negative: Failure - * 0: Success - * Positive: When we have a managed CPU and the sysfs got symlinked - */ -static int cpufreq_add_dev_policy(unsigned int cpu, - struct cpufreq_policy *policy, - struct device *dev) -{ - int ret = 0; -#ifdef CONFIG_SMP - unsigned long flags; - unsigned int j; -#ifdef CONFIG_HOTPLUG_CPU - struct cpufreq_governor *gov; - - gov = __find_governor(per_cpu(cpufreq_cpu_governor, cpu)); - if (gov) { - policy->governor = gov; - pr_debug("Restoring governor %s for cpu %d\n", - policy->governor->name, cpu); - } -#endif - - for_each_cpu(j, policy->cpus) { - struct cpufreq_policy *managed_policy; - - if (cpu == j) - continue; - - /* Check for existing affected CPUs. - * They may not be aware of it due to CPU Hotplug. - * cpufreq_cpu_put is called when the device is removed - * in __cpufreq_remove_dev() - */ - managed_policy = cpufreq_cpu_get(j); - if (unlikely(managed_policy)) { - - /* Set proper policy_cpu */ - unlock_policy_rwsem_write(cpu); - per_cpu(cpufreq_policy_cpu, cpu) = managed_policy->cpu; - - if (lock_policy_rwsem_write(cpu) < 0) { - /* Should not go through policy unlock path */ - if (cpufreq_driver->exit) - cpufreq_driver->exit(policy); - cpufreq_cpu_put(managed_policy); - return -EBUSY; - } - - __cpufreq_governor(managed_policy, CPUFREQ_GOV_STOP); - - spin_lock_irqsave(&cpufreq_driver_lock, flags); - cpumask_copy(managed_policy->cpus, policy->cpus); - per_cpu(cpufreq_cpu_data, cpu) = managed_policy; - spin_unlock_irqrestore(&cpufreq_driver_lock, flags); - - __cpufreq_governor(managed_policy, CPUFREQ_GOV_START); - __cpufreq_governor(managed_policy, CPUFREQ_GOV_LIMITS); - - pr_debug("CPU already managed, adding link\n"); - ret = sysfs_create_link(&dev->kobj, - &managed_policy->kobj, - "cpufreq"); - if (ret) - cpufreq_cpu_put(managed_policy); - /* - * Success. We only needed to be added to the mask. - * Call driver->exit() because only the cpu parent of - * the kobj needed to call init(). - */ - if (cpufreq_driver->exit) - cpufreq_driver->exit(policy); - - if (!ret) - return 1; - else - return ret; - } - } -#endif - return ret; -} - - /* symlink affected CPUs */ static int cpufreq_add_dev_symlink(unsigned int cpu, struct cpufreq_policy *policy) @@ -893,6 +807,42 @@ err_out_kobj_put: return ret; } +#ifdef CONFIG_HOTPLUG_CPU +static int cpufreq_add_policy_cpu(unsigned int cpu, unsigned int sibling, + struct device *dev) +{ + struct cpufreq_policy *policy; + int ret = 0; + unsigned long flags; + + policy = cpufreq_cpu_get(sibling); + WARN_ON(!policy); + + per_cpu(cpufreq_policy_cpu, cpu) = policy->cpu; + + lock_policy_rwsem_write(cpu); + + __cpufreq_governor(policy, CPUFREQ_GOV_STOP); + + spin_lock_irqsave(&cpufreq_driver_lock, flags); + cpumask_set_cpu(cpu, policy->cpus); + per_cpu(cpufreq_cpu_data, cpu) = policy; + spin_unlock_irqrestore(&cpufreq_driver_lock, flags); + + __cpufreq_governor(policy, CPUFREQ_GOV_START); + __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); + + unlock_policy_rwsem_write(cpu); + + ret = sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq"); + if (ret) { + cpufreq_cpu_put(policy); + return ret; + } + + return 0; +} +#endif /** * cpufreq_add_dev - add a CPU device @@ -905,12 +855,12 @@ err_out_kobj_put: */ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) { - unsigned int cpu = dev->id; - int ret = 0, found = 0; + unsigned int j, cpu = dev->id; + int ret = -ENOMEM, found = 0; struct cpufreq_policy *policy; unsigned long flags; - unsigned int j; #ifdef CONFIG_HOTPLUG_CPU + struct cpufreq_governor *gov; int sibling; #endif @@ -927,6 +877,15 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) cpufreq_cpu_put(policy); return 0; } + +#ifdef CONFIG_HOTPLUG_CPU + /* Check if this cpu was hot-unplugged earlier and has siblings */ + for_each_online_cpu(sibling) { + struct cpufreq_policy *cp = per_cpu(cpufreq_cpu_data, sibling); + if (cp && cpumask_test_cpu(cpu, cp->related_cpus)) + return cpufreq_add_policy_cpu(cpu, sibling, dev); + } +#endif #endif if (!try_module_get(cpufreq_driver->owner)) { @@ -934,7 +893,6 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) goto module_out; } - ret = -ENOMEM; policy = kzalloc(sizeof(struct cpufreq_policy), GFP_KERNEL); if (!policy) goto nomem_out; @@ -992,14 +950,14 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) blocking_notifier_call_chain(&cpufreq_policy_notifier_list, CPUFREQ_START, policy); - ret = cpufreq_add_dev_policy(cpu, policy, dev); - if (ret) { - if (ret > 0) - /* This is a managed cpu, symlink created, - exit with 0 */ - ret = 0; - goto err_unlock_policy; +#ifdef CONFIG_HOTPLUG_CPU + gov = __find_governor(per_cpu(cpufreq_cpu_governor, cpu)); + if (gov) { + policy->governor = gov; + pr_debug("Restoring governor %s for cpu %d\n", + policy->governor->name, cpu); } +#endif ret = cpufreq_add_dev_interface(cpu, policy, dev); if (ret) @@ -1013,7 +971,6 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) return 0; - err_out_unregister: spin_lock_irqsave(&cpufreq_driver_lock, flags); for_each_cpu(j, policy->cpus) |