diff options
Diffstat (limited to 'drivers/cpufreq/cpufreq.c')
| -rw-r--r-- | drivers/cpufreq/cpufreq.c | 166 |
1 files changed, 102 insertions, 64 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 9582de1c9ca..9b6ae7dc8b8 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -5,7 +5,9 @@ * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> * * Oct 2005 - Ashok Raj <ashok.raj@intel.com> - * Added handling for CPU hotplug + * Added handling for CPU hotplug + * Feb 2006 - Jacob Shin <jacob.shin@amd.com> + * Fix handling for CPU hotplug -- affected CPUs * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as @@ -44,15 +46,14 @@ static int __cpufreq_governor(struct cpufreq_policy *policy, unsigned int event) static void handle_update(void *data); /** - * Two notifier lists: the "policy" list is involved in the - * validation process for a new CPU frequency policy; the + * Two notifier lists: the "policy" list is involved in the + * validation process for a new CPU frequency policy; the * "transition" list for kernel code that needs to handle * changes to devices when the CPU clock speed changes. * The mutex locks both lists. */ -static struct notifier_block *cpufreq_policy_notifier_list; -static struct notifier_block *cpufreq_transition_notifier_list; -static DECLARE_RWSEM (cpufreq_notifier_rwsem); +static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); +static BLOCKING_NOTIFIER_HEAD(cpufreq_transition_notifier_list); static LIST_HEAD(cpufreq_governor_list); @@ -151,7 +152,7 @@ void cpufreq_debug_printk(unsigned int type, const char *prefix, const char *fmt va_list args; unsigned int len; unsigned long flags; - + WARN_ON(!prefix); if (type & debug) { spin_lock_irqsave(&disable_ratelimit_lock, flags); @@ -198,7 +199,7 @@ static inline void cpufreq_debug_disable_ratelimit(void) { return; } * * This function alters the system "loops_per_jiffy" for the clock * speed change. Note that loops_per_jiffy cannot be updated on SMP - * systems as each CPU might be scaled differently. So, use the arch + * systems as each CPU might be scaled differently. So, use the arch * per-CPU loops_per_jiffy value wherever possible. */ #ifndef CONFIG_SMP @@ -233,7 +234,7 @@ static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) { * * This function calls the transition notifiers and the "adjust_jiffies" * function. It is called twice on all CPU frequency changes that have - * external effects. + * external effects. */ void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state) { @@ -245,13 +246,11 @@ void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state) dprintk("notification %u of frequency transition to %u kHz\n", state, freqs->new); - down_read(&cpufreq_notifier_rwsem); - policy = cpufreq_cpu_data[freqs->cpu]; switch (state) { case CPUFREQ_PRECHANGE: - /* detect if the driver reported a value as "old frequency" + /* detect if the driver reported a value as "old frequency" * which is not equal to what the cpufreq core thinks is * "old frequency". */ @@ -264,20 +263,19 @@ void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state) freqs->old = policy->cur; } } - notifier_call_chain(&cpufreq_transition_notifier_list, - CPUFREQ_PRECHANGE, freqs); + blocking_notifier_call_chain(&cpufreq_transition_notifier_list, + CPUFREQ_PRECHANGE, freqs); adjust_jiffies(CPUFREQ_PRECHANGE, freqs); break; case CPUFREQ_POSTCHANGE: adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); - notifier_call_chain(&cpufreq_transition_notifier_list, - CPUFREQ_POSTCHANGE, freqs); + blocking_notifier_call_chain(&cpufreq_transition_notifier_list, + CPUFREQ_POSTCHANGE, freqs); if (likely(policy) && likely(policy->cpu == freqs->cpu)) policy->cur = freqs->new; break; } - up_read(&cpufreq_notifier_rwsem); } EXPORT_SYMBOL_GPL(cpufreq_notify_transition); @@ -335,11 +333,11 @@ extern struct sysdev_class cpu_sysdev_class; * "unsigned int". */ -#define show_one(file_name, object) \ -static ssize_t show_##file_name \ -(struct cpufreq_policy * policy, char *buf) \ -{ \ - return sprintf (buf, "%u\n", policy->object); \ +#define show_one(file_name, object) \ +static ssize_t show_##file_name \ +(struct cpufreq_policy * policy, char *buf) \ +{ \ + return sprintf (buf, "%u\n", policy->object); \ } show_one(cpuinfo_min_freq, cpuinfo.min_freq); @@ -404,8 +402,8 @@ static ssize_t show_scaling_governor (struct cpufreq_policy * policy, char *buf) /** * store_scaling_governor - store policy for the specified CPU */ -static ssize_t store_scaling_governor (struct cpufreq_policy * policy, - const char *buf, size_t count) +static ssize_t store_scaling_governor (struct cpufreq_policy * policy, + const char *buf, size_t count) { unsigned int ret = -EINVAL; char str_governor[16]; @@ -528,7 +526,7 @@ static ssize_t show(struct kobject * kobj, struct attribute * attr ,char * buf) return ret; } -static ssize_t store(struct kobject * kobj, struct attribute * attr, +static ssize_t store(struct kobject * kobj, struct attribute * attr, const char * buf, size_t count) { struct cpufreq_policy * policy = to_policy(kobj); @@ -564,7 +562,7 @@ static struct kobj_type ktype_cpufreq = { /** * cpufreq_add_dev - add a CPU device * - * Adds the cpufreq interface for a CPU device. + * Adds the cpufreq interface for a CPU device. */ static int cpufreq_add_dev (struct sys_device * sys_dev) { @@ -573,8 +571,12 @@ static int cpufreq_add_dev (struct sys_device * sys_dev) struct cpufreq_policy new_policy; struct cpufreq_policy *policy; struct freq_attr **drv_attr; + struct sys_device *cpu_sys_dev; unsigned long flags; unsigned int j; +#ifdef CONFIG_SMP + struct cpufreq_policy *managed_policy; +#endif if (cpu_is_offline(cpu)) return 0; @@ -587,8 +589,7 @@ static int cpufreq_add_dev (struct sys_device * sys_dev) * CPU because it is in the same boat. */ policy = cpufreq_cpu_get(cpu); if (unlikely(policy)) { - dprintk("CPU already managed, adding link\n"); - sysfs_create_link(&sys_dev->kobj, &policy->kobj, "cpufreq"); + cpufreq_cpu_put(policy); cpufreq_debug_enable_ratelimit(); return 0; } @@ -623,6 +624,32 @@ static int cpufreq_add_dev (struct sys_device * sys_dev) goto err_out; } +#ifdef CONFIG_SMP + for_each_cpu_mask(j, policy->cpus) { + if (cpu == j) + continue; + + /* check for existing affected CPUs. They may not be aware + * of it due to CPU Hotplug. + */ + managed_policy = cpufreq_cpu_get(j); + if (unlikely(managed_policy)) { + spin_lock_irqsave(&cpufreq_driver_lock, flags); + managed_policy->cpus = policy->cpus; + cpufreq_cpu_data[cpu] = managed_policy; + spin_unlock_irqrestore(&cpufreq_driver_lock, flags); + + dprintk("CPU already managed, adding link\n"); + sysfs_create_link(&sys_dev->kobj, + &managed_policy->kobj, "cpufreq"); + + cpufreq_debug_enable_ratelimit(); + mutex_unlock(&policy->lock); + ret = 0; + goto err_out_driver_exit; /* call driver->exit() */ + } + } +#endif memcpy(&new_policy, policy, sizeof(struct cpufreq_policy)); /* prepare interface data */ @@ -650,6 +677,21 @@ static int cpufreq_add_dev (struct sys_device * sys_dev) for_each_cpu_mask(j, policy->cpus) cpufreq_cpu_data[j] = policy; spin_unlock_irqrestore(&cpufreq_driver_lock, flags); + + /* symlink affected CPUs */ + for_each_cpu_mask(j, policy->cpus) { + if (j == cpu) + continue; + if (!cpu_online(j)) + continue; + + dprintk("CPU already managed, adding link\n"); + cpufreq_cpu_get(cpu); + cpu_sys_dev = get_cpu_sysdev(j); + sysfs_create_link(&cpu_sys_dev->kobj, &policy->kobj, + "cpufreq"); + } + policy->governor = NULL; /* to assure that the starting sequence is * run in cpufreq_set_policy */ mutex_unlock(&policy->lock); @@ -724,10 +766,11 @@ static int cpufreq_remove_dev (struct sys_device * sys_dev) #ifdef CONFIG_SMP /* if this isn't the CPU which is the parent of the kobj, we - * only need to unlink, put and exit + * only need to unlink, put and exit */ if (unlikely(cpu != data->cpu)) { dprintk("removing link\n"); + cpu_clear(cpu, data->cpus); spin_unlock_irqrestore(&cpufreq_driver_lock, flags); sysfs_remove_link(&sys_dev->kobj, "cpufreq"); cpufreq_cpu_put(data); @@ -740,7 +783,7 @@ static int cpufreq_remove_dev (struct sys_device * sys_dev) if (!kobject_get(&data->kobj)) { spin_unlock_irqrestore(&cpufreq_driver_lock, flags); cpufreq_debug_enable_ratelimit(); - return -EFAULT; + return -EFAULT; } #ifdef CONFIG_SMP @@ -783,7 +826,7 @@ static int cpufreq_remove_dev (struct sys_device * sys_dev) kobject_put(&data->kobj); /* we need to make sure that the underlying kobj is actually - * not referenced anymore by anybody before we proceed with + * not referenced anymore by anybody before we proceed with * unloading. */ dprintk("waiting for dropping of refcount\n"); @@ -831,7 +874,7 @@ static void cpufreq_out_of_sync(unsigned int cpu, unsigned int old_freq, unsigne } -/** +/** * cpufreq_quick_get - get the CPU frequency (in kHz) frpm policy->cur * @cpu: CPU number * @@ -855,7 +898,7 @@ unsigned int cpufreq_quick_get(unsigned int cpu) EXPORT_SYMBOL(cpufreq_quick_get); -/** +/** * cpufreq_get - get the current CPU frequency (in kHz) * @cpu: CPU number * @@ -960,7 +1003,7 @@ static int cpufreq_suspend(struct sys_device * sysdev, pm_message_t pmsg) freqs.old = cpu_policy->cur; freqs.new = cur_freq; - notifier_call_chain(&cpufreq_transition_notifier_list, + blocking_notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_SUSPENDCHANGE, &freqs); adjust_jiffies(CPUFREQ_SUSPENDCHANGE, &freqs); @@ -1041,7 +1084,8 @@ static int cpufreq_resume(struct sys_device * sysdev) freqs.old = cpu_policy->cur; freqs.new = cur_freq; - notifier_call_chain(&cpufreq_transition_notifier_list, + blocking_notifier_call_chain( + &cpufreq_transition_notifier_list, CPUFREQ_RESUMECHANGE, &freqs); adjust_jiffies(CPUFREQ_RESUMECHANGE, &freqs); @@ -1072,30 +1116,30 @@ static struct sysdev_driver cpufreq_sysdev_driver = { * @nb: notifier function to register * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER * - * Add a driver to one of two lists: either a list of drivers that + * Add a driver to one of two lists: either a list of drivers that * are notified about clock rate changes (once before and once after * the transition), or a list of drivers that are notified about * changes in cpufreq policy. * * This function may sleep, and has the same return conditions as - * notifier_chain_register. + * blocking_notifier_chain_register. */ int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) { int ret; - down_write(&cpufreq_notifier_rwsem); switch (list) { case CPUFREQ_TRANSITION_NOTIFIER: - ret = notifier_chain_register(&cpufreq_transition_notifier_list, nb); + ret = blocking_notifier_chain_register( + &cpufreq_transition_notifier_list, nb); break; case CPUFREQ_POLICY_NOTIFIER: - ret = notifier_chain_register(&cpufreq_policy_notifier_list, nb); + ret = blocking_notifier_chain_register( + &cpufreq_policy_notifier_list, nb); break; default: ret = -EINVAL; } - up_write(&cpufreq_notifier_rwsem); return ret; } @@ -1110,24 +1154,24 @@ EXPORT_SYMBOL(cpufreq_register_notifier); * Remove a driver from the CPU frequency notifier list. * * This function may sleep, and has the same return conditions as - * notifier_chain_unregister. + * blocking_notifier_chain_unregister. */ int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) { int ret; - down_write(&cpufreq_notifier_rwsem); switch (list) { case CPUFREQ_TRANSITION_NOTIFIER: - ret = notifier_chain_unregister(&cpufreq_transition_notifier_list, nb); + ret = blocking_notifier_chain_unregister( + &cpufreq_transition_notifier_list, nb); break; case CPUFREQ_POLICY_NOTIFIER: - ret = notifier_chain_unregister(&cpufreq_policy_notifier_list, nb); + ret = blocking_notifier_chain_unregister( + &cpufreq_policy_notifier_list, nb); break; default: ret = -EINVAL; } - up_write(&cpufreq_notifier_rwsem); return ret; } @@ -1225,7 +1269,7 @@ int cpufreq_register_governor(struct cpufreq_governor *governor) return -EINVAL; mutex_lock(&cpufreq_governor_mutex); - + list_for_each_entry(t, &cpufreq_governor_list, governor_list) { if (!strnicmp(governor->name,t->name,CPUFREQ_NAME_LEN)) { mutex_unlock(&cpufreq_governor_mutex); @@ -1234,7 +1278,7 @@ int cpufreq_register_governor(struct cpufreq_governor *governor) } list_add(&governor->governor_list, &cpufreq_governor_list); - mutex_unlock(&cpufreq_governor_mutex); + mutex_unlock(&cpufreq_governor_mutex); return 0; } EXPORT_SYMBOL_GPL(cpufreq_register_governor); @@ -1299,29 +1343,23 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_poli if (ret) goto error_out; - down_read(&cpufreq_notifier_rwsem); - /* adjust if necessary - all reasons */ - notifier_call_chain(&cpufreq_policy_notifier_list, CPUFREQ_ADJUST, - policy); + blocking_notifier_call_chain(&cpufreq_policy_notifier_list, + CPUFREQ_ADJUST, policy); /* adjust if necessary - hardware incompatibility*/ - notifier_call_chain(&cpufreq_policy_notifier_list, CPUFREQ_INCOMPATIBLE, - policy); + blocking_notifier_call_chain(&cpufreq_policy_notifier_list, + CPUFREQ_INCOMPATIBLE, policy); /* verify the cpu speed can be set within this limit, which might be different to the first one */ ret = cpufreq_driver->verify(policy); - if (ret) { - up_read(&cpufreq_notifier_rwsem); + if (ret) goto error_out; - } /* notification of the new policy */ - notifier_call_chain(&cpufreq_policy_notifier_list, CPUFREQ_NOTIFY, - policy); - - up_read(&cpufreq_notifier_rwsem); + blocking_notifier_call_chain(&cpufreq_policy_notifier_list, + CPUFREQ_NOTIFY, policy); data->min = policy->min; data->max = policy->max; @@ -1497,9 +1535,9 @@ static struct notifier_block cpufreq_cpu_notifier = * @driver_data: A struct cpufreq_driver containing the values# * submitted by the CPU Frequency driver. * - * Registers a CPU Frequency driver to this core code. This code + * Registers a CPU Frequency driver to this core code. This code * returns zero on success, -EBUSY when another driver got here first - * (and isn't unregistered in the meantime). + * (and isn't unregistered in the meantime). * */ int cpufreq_register_driver(struct cpufreq_driver *driver_data) @@ -1560,7 +1598,7 @@ EXPORT_SYMBOL_GPL(cpufreq_register_driver); /** * cpufreq_unregister_driver - unregister the current CPUFreq driver * - * Unregister the current CPUFreq driver. Only call this if you have + * Unregister the current CPUFreq driver. Only call this if you have * the right to do so, i.e. if you have succeeded in initialising before! * Returns zero if successful, and -EINVAL if the cpufreq_driver is * currently not initialised. |