* (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
*
* Oct 2005 - Ashok Raj <ashok.raj@intel.com>
- * Added handling for CPU hotplug
- * Feb 2006 - Jacob Shin <jacob.shin@amd.com>
- * Fix handling for CPU hotplug -- affected CPUs
+ * Added handling for CPU hotplug
*
* 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
*
*/
+#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
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 BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list);
-static BLOCKING_NOTIFIER_HEAD(cpufreq_transition_notifier_list);
+static struct notifier_block *cpufreq_policy_notifier_list;
+static struct notifier_block *cpufreq_transition_notifier_list;
+static DECLARE_RWSEM (cpufreq_notifier_rwsem);
static LIST_HEAD(cpufreq_governor_list);
va_list args;
unsigned int len;
unsigned long flags;
-
+
WARN_ON(!prefix);
if (type & debug) {
spin_lock_irqsave(&disable_ratelimit_lock, flags);
*
* 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
*
* 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)
{
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".
*/
if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
if ((policy) && (policy->cpu == freqs->cpu) &&
(policy->cur) && (policy->cur != freqs->old)) {
- dprintk("Warning: CPU frequency is"
+ dprintk(KERN_WARNING "Warning: CPU frequency is"
" %u, cpufreq assumed %u kHz.\n",
freqs->old, policy->cur);
freqs->old = policy->cur;
}
}
- blocking_notifier_call_chain(&cpufreq_transition_notifier_list,
- CPUFREQ_PRECHANGE, freqs);
+ notifier_call_chain(&cpufreq_transition_notifier_list,
+ CPUFREQ_PRECHANGE, freqs);
adjust_jiffies(CPUFREQ_PRECHANGE, freqs);
break;
case CPUFREQ_POSTCHANGE:
adjust_jiffies(CPUFREQ_POSTCHANGE, freqs);
- blocking_notifier_call_chain(&cpufreq_transition_notifier_list,
- CPUFREQ_POSTCHANGE, freqs);
+ 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);
* SYSFS INTERFACE *
*********************************************************************/
-static struct cpufreq_governor *__find_governor(const char *str_governor)
-{
- struct cpufreq_governor *t;
-
- list_for_each_entry(t, &cpufreq_governor_list, governor_list)
- if (!strnicmp(str_governor,t->name,CPUFREQ_NAME_LEN))
- return t;
-
- return NULL;
-}
-
/**
* cpufreq_parse_governor - parse a governor string
*/
static int cpufreq_parse_governor (char *str_governor, unsigned int *policy,
struct cpufreq_governor **governor)
{
- int err = -EINVAL;
-
if (!cpufreq_driver)
- goto out;
-
+ return -EINVAL;
if (cpufreq_driver->setpolicy) {
if (!strnicmp(str_governor, "performance", CPUFREQ_NAME_LEN)) {
*policy = CPUFREQ_POLICY_PERFORMANCE;
- err = 0;
+ return 0;
} else if (!strnicmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) {
*policy = CPUFREQ_POLICY_POWERSAVE;
- err = 0;
+ return 0;
}
- } else if (cpufreq_driver->target) {
+ return -EINVAL;
+ } else {
struct cpufreq_governor *t;
-
mutex_lock(&cpufreq_governor_mutex);
-
- t = __find_governor(str_governor);
-
- if (t == NULL) {
- char *name = kasprintf(GFP_KERNEL, "cpufreq_%s", str_governor);
-
- if (name) {
- int ret;
-
+ if (!cpufreq_driver || !cpufreq_driver->target)
+ goto out;
+ list_for_each_entry(t, &cpufreq_governor_list, governor_list) {
+ if (!strnicmp(str_governor,t->name,CPUFREQ_NAME_LEN)) {
+ *governor = t;
mutex_unlock(&cpufreq_governor_mutex);
- ret = request_module(name);
- mutex_lock(&cpufreq_governor_mutex);
-
- if (ret == 0)
- t = __find_governor(str_governor);
+ return 0;
}
-
- kfree(name);
- }
-
- if (t != NULL) {
- *governor = t;
- err = 0;
}
-
+out:
mutex_unlock(&cpufreq_governor_mutex);
}
- out:
- return err;
+ return -EINVAL;
}
+EXPORT_SYMBOL_GPL(cpufreq_parse_governor);
/* drivers/base/cpu.c */
* "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);
show_one(scaling_max_freq, max);
show_one(scaling_cur_freq, cur);
-static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_policy *policy);
-
/**
* cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access
*/
if (ret != 1) \
return -EINVAL; \
\
- lock_cpu_hotplug(); \
- mutex_lock(&policy->lock); \
- ret = __cpufreq_set_policy(policy, &new_policy); \
- policy->user_policy.object = policy->object; \
- mutex_unlock(&policy->lock); \
- unlock_cpu_hotplug(); \
+ ret = cpufreq_set_policy(&new_policy); \
\
return ret ? ret : count; \
}
/**
* 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];
if (cpufreq_parse_governor(str_governor, &new_policy.policy, &new_policy.governor))
return -EINVAL;
- lock_cpu_hotplug();
-
- /* Do not use cpufreq_set_policy here or the user_policy.max
- will be wrongly overridden */
- mutex_lock(&policy->lock);
- ret = __cpufreq_set_policy(policy, &new_policy);
-
- policy->user_policy.policy = policy->policy;
- policy->user_policy.governor = policy->governor;
- mutex_unlock(&policy->lock);
-
- unlock_cpu_hotplug();
-
+ ret = cpufreq_set_policy(&new_policy);
return ret ? ret : count;
}
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);
/**
* 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)
{
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;
* CPU because it is in the same boat. */
policy = cpufreq_cpu_get(cpu);
if (unlikely(policy)) {
- cpufreq_cpu_put(policy);
+ dprintk("CPU already managed, adding link\n");
+ sysfs_create_link(&sys_dev->kobj, &policy->kobj, "cpufreq");
cpufreq_debug_enable_ratelimit();
return 0;
}
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 */
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 %u already managed, adding link\n", j);
- 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);
-
+
/* set default policy */
+
ret = cpufreq_set_policy(&new_policy);
if (ret) {
dprintk("setting policy failed\n");
module_put(cpufreq_driver->owner);
dprintk("initialization complete\n");
cpufreq_debug_enable_ratelimit();
-
+
return 0;
#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);
if (!kobject_get(&data->kobj)) {
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
cpufreq_debug_enable_ratelimit();
- return -EFAULT;
+ return -EFAULT;
}
#ifdef CONFIG_SMP
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");
{
struct cpufreq_freqs freqs;
- dprintk("Warning: CPU frequency out of sync: cpufreq and timing "
+ dprintk(KERN_WARNING "Warning: CPU frequency out of sync: cpufreq and timing "
"core thinks of %u, is %u kHz.\n", old_freq, new_freq);
freqs.cpu = cpu;
}
-/**
+/**
* cpufreq_quick_get - get the CPU frequency (in kHz) frpm policy->cur
* @cpu: CPU number
*
EXPORT_SYMBOL(cpufreq_quick_get);
-/**
+/**
* cpufreq_get - get the current CPU frequency (in kHz)
* @cpu: CPU number
*
struct cpufreq_freqs freqs;
if (!(cpufreq_driver->flags & CPUFREQ_PM_NO_WARN))
- dprintk("Warning: CPU frequency is %u, "
+ dprintk(KERN_DEBUG "Warning: CPU frequency is %u, "
"cpufreq assumed %u kHz.\n",
cur_freq, cpu_policy->cur);
freqs.old = cpu_policy->cur;
freqs.new = cur_freq;
- blocking_notifier_call_chain(&cpufreq_transition_notifier_list,
+ notifier_call_chain(&cpufreq_transition_notifier_list,
CPUFREQ_SUSPENDCHANGE, &freqs);
adjust_jiffies(CPUFREQ_SUSPENDCHANGE, &freqs);
struct cpufreq_freqs freqs;
if (!(cpufreq_driver->flags & CPUFREQ_PM_NO_WARN))
- dprintk("Warning: CPU frequency"
+ dprintk(KERN_WARNING "Warning: CPU frequency"
"is %u, cpufreq assumed %u kHz.\n",
cur_freq, cpu_policy->cur);
freqs.old = cpu_policy->cur;
freqs.new = cur_freq;
- blocking_notifier_call_chain(
- &cpufreq_transition_notifier_list,
+ notifier_call_chain(&cpufreq_transition_notifier_list,
CPUFREQ_RESUMECHANGE, &freqs);
adjust_jiffies(CPUFREQ_RESUMECHANGE, &freqs);
* @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
- * blocking_notifier_chain_register.
+ * 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 = blocking_notifier_chain_register(
- &cpufreq_transition_notifier_list, nb);
+ ret = notifier_chain_register(&cpufreq_transition_notifier_list, nb);
break;
case CPUFREQ_POLICY_NOTIFIER:
- ret = blocking_notifier_chain_register(
- &cpufreq_policy_notifier_list, nb);
+ ret = notifier_chain_register(&cpufreq_policy_notifier_list, nb);
break;
default:
ret = -EINVAL;
}
+ up_write(&cpufreq_notifier_rwsem);
return ret;
}
* Remove a driver from the CPU frequency notifier list.
*
* This function may sleep, and has the same return conditions as
- * blocking_notifier_chain_unregister.
+ * 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 = blocking_notifier_chain_unregister(
- &cpufreq_transition_notifier_list, nb);
+ ret = notifier_chain_unregister(&cpufreq_transition_notifier_list, nb);
break;
case CPUFREQ_POLICY_NOTIFIER:
- ret = blocking_notifier_chain_unregister(
- &cpufreq_policy_notifier_list, nb);
+ ret = notifier_chain_unregister(&cpufreq_policy_notifier_list, nb);
break;
default:
ret = -EINVAL;
}
+ up_write(&cpufreq_notifier_rwsem);
return ret;
}
*********************************************************************/
-/* Must be called with lock_cpu_hotplug held */
int __cpufreq_driver_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
int retval = -EINVAL;
+ lock_cpu_hotplug();
dprintk("target for CPU %u: %u kHz, relation %u\n", policy->cpu,
target_freq, relation);
if (cpu_online(policy->cpu) && cpufreq_driver->target)
retval = cpufreq_driver->target(policy, target_freq, relation);
+ unlock_cpu_hotplug();
+
return retval;
}
EXPORT_SYMBOL_GPL(__cpufreq_driver_target);
if (!policy)
return -EINVAL;
- lock_cpu_hotplug();
mutex_lock(&policy->lock);
ret = __cpufreq_driver_target(policy, target_freq, relation);
mutex_unlock(&policy->lock);
- unlock_cpu_hotplug();
cpufreq_cpu_put(policy);
return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_driver_target);
-/*
- * Locking: Must be called with the lock_cpu_hotplug() lock held
- * when "event" is CPUFREQ_GOV_LIMITS
- */
static int __cpufreq_governor(struct cpufreq_policy *policy, unsigned int event)
{
}
+int cpufreq_governor(unsigned int cpu, unsigned int event)
+{
+ int ret = 0;
+ struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+
+ if (!policy)
+ return -EINVAL;
+
+ mutex_lock(&policy->lock);
+ ret = __cpufreq_governor(policy, event);
+ mutex_unlock(&policy->lock);
+
+ cpufreq_cpu_put(policy);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(cpufreq_governor);
+
+
int cpufreq_register_governor(struct cpufreq_governor *governor)
{
- int err;
+ struct cpufreq_governor *t;
if (!governor)
return -EINVAL;
mutex_lock(&cpufreq_governor_mutex);
-
- err = -EBUSY;
- if (__find_governor(governor->name) == NULL) {
- err = 0;
- list_add(&governor->governor_list, &cpufreq_governor_list);
+
+ list_for_each_entry(t, &cpufreq_governor_list, governor_list) {
+ if (!strnicmp(governor->name,t->name,CPUFREQ_NAME_LEN)) {
+ mutex_unlock(&cpufreq_governor_mutex);
+ return -EBUSY;
+ }
}
+ list_add(&governor->governor_list, &cpufreq_governor_list);
- mutex_unlock(&cpufreq_governor_mutex);
- return err;
+ mutex_unlock(&cpufreq_governor_mutex);
+ return 0;
}
EXPORT_SYMBOL_GPL(cpufreq_register_governor);
EXPORT_SYMBOL(cpufreq_get_policy);
-/*
- * Locking: Must be called with the lock_cpu_hotplug() lock held
- */
static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_policy *policy)
{
int ret = 0;
memcpy(&policy->cpuinfo, &data->cpuinfo, sizeof(struct cpufreq_cpuinfo));
- if (policy->min > data->min && policy->min > policy->max) {
- ret = -EINVAL;
- goto error_out;
- }
-
/* verify the cpu speed can be set within this limit */
ret = cpufreq_driver->verify(policy);
if (ret)
goto error_out;
+ down_read(&cpufreq_notifier_rwsem);
+
/* adjust if necessary - all reasons */
- blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
- CPUFREQ_ADJUST, policy);
+ notifier_call_chain(&cpufreq_policy_notifier_list, CPUFREQ_ADJUST,
+ policy);
/* adjust if necessary - hardware incompatibility*/
- blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
- CPUFREQ_INCOMPATIBLE, policy);
+ 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)
+ if (ret) {
+ up_read(&cpufreq_notifier_rwsem);
goto error_out;
+ }
/* notification of the new policy */
- blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
- CPUFREQ_NOTIFY, policy);
+ notifier_call_chain(&cpufreq_policy_notifier_list, CPUFREQ_NOTIFY,
+ policy);
+
+ up_read(&cpufreq_notifier_rwsem);
data->min = policy->min;
data->max = policy->max;
if (!data)
return -EINVAL;
- lock_cpu_hotplug();
-
/* lock this CPU */
mutex_lock(&data->lock);
data->user_policy.governor = data->governor;
mutex_unlock(&data->lock);
-
- unlock_cpu_hotplug();
cpufreq_cpu_put(data);
return ret;
if (!data)
return -ENODEV;
- lock_cpu_hotplug();
mutex_lock(&data->lock);
dprintk("updating policy for CPU %u\n", cpu);
ret = __cpufreq_set_policy(data, &policy);
mutex_unlock(&data->lock);
- unlock_cpu_hotplug();
+
cpufreq_cpu_put(data);
return ret;
}
EXPORT_SYMBOL(cpufreq_update_policy);
-#ifdef CONFIG_HOTPLUG_CPU
-static int cpufreq_cpu_callback(struct notifier_block *nfb,
+static int __cpuinit cpufreq_cpu_callback(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
unsigned int cpu = (unsigned long)hcpu;
return NOTIFY_OK;
}
-static struct notifier_block __cpuinitdata cpufreq_cpu_notifier =
+static struct notifier_block cpufreq_cpu_notifier =
{
.notifier_call = cpufreq_cpu_callback,
};
-#endif /* CONFIG_HOTPLUG_CPU */
/*********************************************************************
* REGISTER / UNREGISTER CPUFREQ DRIVER *
* @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)
}
if (!ret) {
- register_hotcpu_notifier(&cpufreq_cpu_notifier);
+ register_cpu_notifier(&cpufreq_cpu_notifier);
dprintk("driver %s up and running\n", driver_data->name);
cpufreq_debug_enable_ratelimit();
}
/**
* 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.
dprintk("unregistering driver %s\n", driver->name);
sysdev_driver_unregister(&cpu_sysdev_class, &cpufreq_sysdev_driver);
- unregister_hotcpu_notifier(&cpufreq_cpu_notifier);
+ unregister_cpu_notifier(&cpufreq_cpu_notifier);
spin_lock_irqsave(&cpufreq_driver_lock, flags);
cpufreq_driver = NULL;
git://git.onelab.eu / linux-2.6.git / blobdiff