* Copyright (C) 2001 Russell King
* (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
+ *
* 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
* published by the Free Software Foundation.
*
*/
-#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/cpu.h>
#include <linux/completion.h>
+#include <linux/mutex.h>
-#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_CORE, "cpufreq-core", msg)
+#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_CORE, \
+ "cpufreq-core", msg)
/**
- * The "cpufreq driver" - the arch- or hardware-dependend low
+ * The "cpufreq driver" - the arch- or hardware-dependent low
* level driver of CPUFreq support, and its spinlock. This lock
* also protects the cpufreq_cpu_data array.
*/
-static struct cpufreq_driver *cpufreq_driver;
-static struct cpufreq_policy *cpufreq_cpu_data[NR_CPUS];
+static struct cpufreq_driver *cpufreq_driver;
+static struct cpufreq_policy *cpufreq_cpu_data[NR_CPUS];
static DEFINE_SPINLOCK(cpufreq_driver_lock);
-
-/* we keep a copy of all ->add'ed CPU's struct sys_device here;
- * as it is only accessed in ->add and ->remove, no lock or reference
- * count is necessary.
- */
-static struct sys_device *cpu_sys_devices[NR_CPUS];
-
-
/* internal prototypes */
static int __cpufreq_governor(struct cpufreq_policy *policy, unsigned int event);
-static void handle_update(void *data);
-static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci);
+static void handle_update(struct work_struct *work);
/**
- * 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 struct srcu_notifier_head cpufreq_transition_notifier_list;
+static int __init init_cpufreq_transition_notifier_list(void)
+{
+ srcu_init_notifier_head(&cpufreq_transition_notifier_list);
+ return 0;
+}
+pure_initcall(init_cpufreq_transition_notifier_list);
static LIST_HEAD(cpufreq_governor_list);
-static DECLARE_MUTEX (cpufreq_governor_sem);
+static DEFINE_MUTEX (cpufreq_governor_mutex);
-struct cpufreq_policy * cpufreq_cpu_get(unsigned int cpu)
+struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
{
struct cpufreq_policy *data;
unsigned long flags;
if (!kobject_get(&data->kobj))
goto err_out_put_module;
-
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
-
return data;
- err_out_put_module:
+err_out_put_module:
module_put(cpufreq_driver->owner);
- err_out_unlock:
+err_out_unlock:
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
- err_out:
+err_out:
return NULL;
}
EXPORT_SYMBOL_GPL(cpufreq_cpu_get);
+
void cpufreq_cpu_put(struct cpufreq_policy *data)
{
kobject_put(&data->kobj);
static unsigned int disable_ratelimit = 1;
static DEFINE_SPINLOCK(disable_ratelimit_lock);
-static inline void cpufreq_debug_enable_ratelimit(void)
+static void cpufreq_debug_enable_ratelimit(void)
{
unsigned long flags;
spin_unlock_irqrestore(&disable_ratelimit_lock, flags);
}
-static inline void cpufreq_debug_disable_ratelimit(void)
+static void cpufreq_debug_disable_ratelimit(void)
{
unsigned long flags;
spin_unlock_irqrestore(&disable_ratelimit_lock, flags);
}
-void cpufreq_debug_printk(unsigned int type, const char *prefix, const char *fmt, ...)
+void cpufreq_debug_printk(unsigned int type, const char *prefix,
+ const char *fmt, ...)
{
char s[256];
va_list args;
unsigned int len;
unsigned long flags;
-
+
WARN_ON(!prefix);
if (type & debug) {
spin_lock_irqsave(&disable_ratelimit_lock, flags);
- if (!disable_ratelimit && debug_ratelimit && !printk_ratelimit()) {
+ if (!disable_ratelimit && debug_ratelimit
+ && !printk_ratelimit()) {
spin_unlock_irqrestore(&disable_ratelimit_lock, flags);
return;
}
module_param(debug, uint, 0644);
-MODULE_PARM_DESC(debug, "CPUfreq debugging: add 1 to debug core, 2 to debug drivers, and 4 to debug governors.");
+MODULE_PARM_DESC(debug, "CPUfreq debugging: add 1 to debug core,"
+ " 2 to debug drivers, and 4 to debug governors.");
module_param(debug_ratelimit, uint, 0644);
-MODULE_PARM_DESC(debug_ratelimit, "CPUfreq debugging: set to 0 to disable ratelimiting.");
+MODULE_PARM_DESC(debug_ratelimit, "CPUfreq debugging:"
+ " set to 0 to disable ratelimiting.");
#else /* !CONFIG_CPU_FREQ_DEBUG */
*
* 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
static unsigned long l_p_j_ref;
static unsigned int l_p_j_ref_freq;
-static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
+static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
{
if (ci->flags & CPUFREQ_CONST_LOOPS)
return;
if (!l_p_j_ref_freq) {
l_p_j_ref = loops_per_jiffy;
l_p_j_ref_freq = ci->old;
- dprintk("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", l_p_j_ref, l_p_j_ref_freq);
+ dprintk("saving %lu as reference value for loops_per_jiffy;"
+ "freq is %u kHz\n", l_p_j_ref, l_p_j_ref_freq);
}
if ((val == CPUFREQ_PRECHANGE && ci->old < ci->new) ||
(val == CPUFREQ_POSTCHANGE && ci->old > ci->new) ||
- (val == CPUFREQ_RESUMECHANGE)) {
- loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, ci->new);
- dprintk("scaling loops_per_jiffy to %lu for frequency %u kHz\n", loops_per_jiffy, ci->new);
+ (val == CPUFREQ_RESUMECHANGE || val == CPUFREQ_SUSPENDCHANGE)) {
+ loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq,
+ ci->new);
+ dprintk("scaling loops_per_jiffy to %lu"
+ "for frequency %u kHz\n", loops_per_jiffy, ci->new);
}
}
#else
-static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) { return; }
+static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
+{
+ return;
+}
#endif
/**
- * cpufreq_notify_transition - call notifier chain and adjust_jiffies on frequency transition
+ * cpufreq_notify_transition - call notifier chain and adjust_jiffies
+ * on frequency transition.
*
- * This function calls the transition notifiers and the "adjust_jiffies" function. It is called
- * twice on all CPU frequency changes that have external effects.
+ * This function calls the transition notifiers and the "adjust_jiffies"
+ * function. It is called twice on all CPU frequency changes that have
+ * external effects.
*/
void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state)
{
+ struct cpufreq_policy *policy;
+
BUG_ON(irqs_disabled());
freqs->flags = cpufreq_driver->flags;
- dprintk("notification %u of frequency transition to %u kHz\n", state, freqs->new);
+ 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" which
- * is not equal to what the cpufreq core thinks is "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 ((likely(cpufreq_cpu_data[freqs->cpu])) &&
- (likely(cpufreq_cpu_data[freqs->cpu]->cpu == freqs->cpu)) &&
- (likely(cpufreq_cpu_data[freqs->cpu]->cur)) &&
- (unlikely(freqs->old != cpufreq_cpu_data[freqs->cpu]->cur)))
- {
- printk(KERN_WARNING "Warning: CPU frequency is %u, "
- "cpufreq assumed %u kHz.\n", freqs->old, cpufreq_cpu_data[freqs->cpu]->cur);
- freqs->old = cpufreq_cpu_data[freqs->cpu]->cur;
+ if ((policy) && (policy->cpu == freqs->cpu) &&
+ (policy->cur) && (policy->cur != freqs->old)) {
+ dprintk("Warning: CPU frequency is"
+ " %u, cpufreq assumed %u kHz.\n",
+ freqs->old, policy->cur);
+ freqs->old = policy->cur;
}
}
- notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_PRECHANGE, freqs);
+ srcu_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);
- if ((likely(cpufreq_cpu_data[freqs->cpu])) &&
- (likely(cpufreq_cpu_data[freqs->cpu]->cpu == freqs->cpu)))
- cpufreq_cpu_data[freqs->cpu]->cur = freqs->new;
+ srcu_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)
- return -EINVAL;
+ goto out;
+
if (cpufreq_driver->setpolicy) {
if (!strnicmp(str_governor, "performance", CPUFREQ_NAME_LEN)) {
*policy = CPUFREQ_POLICY_PERFORMANCE;
- return 0;
- } else if (!strnicmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) {
+ err = 0;
+ } else if (!strnicmp(str_governor, "powersave",
+ CPUFREQ_NAME_LEN)) {
*policy = CPUFREQ_POLICY_POWERSAVE;
- return 0;
+ err = 0;
}
- return -EINVAL;
- } else {
+ } else if (cpufreq_driver->target) {
struct cpufreq_governor *t;
- down(&cpufreq_governor_sem);
- 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;
- up(&cpufreq_governor_sem);
- return 0;
+
+ 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;
+
+ mutex_unlock(&cpufreq_governor_mutex);
+ ret = request_module(name);
+ mutex_lock(&cpufreq_governor_mutex);
+
+ if (ret == 0)
+ t = __find_governor(str_governor);
}
+
+ kfree(name);
}
- out:
- up(&cpufreq_governor_sem);
+
+ if (t != NULL) {
+ *governor = t;
+ err = 0;
+ }
+
+ mutex_unlock(&cpufreq_governor_mutex);
}
- return -EINVAL;
+ out:
+ return err;
}
-EXPORT_SYMBOL_GPL(cpufreq_parse_governor);
/* drivers/base/cpu.c */
/**
- * cpufreq_per_cpu_attr_read() / show_##file_name() - print out cpufreq information
+ * cpufreq_per_cpu_attr_read() / show_##file_name() -
+ * print out cpufreq information
*
* Write out information from cpufreq_driver->policy[cpu]; object must be
* "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; \
\
- ret = cpufreq_set_policy(&new_policy); \
+ 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(); \
\
return ret ? ret : count; \
}
/**
* show_cpuinfo_cur_freq - current CPU frequency as detected by hardware
*/
-static ssize_t show_cpuinfo_cur_freq (struct cpufreq_policy * policy, char *buf)
+static ssize_t show_cpuinfo_cur_freq (struct cpufreq_policy * policy,
+ char *buf)
{
unsigned int cur_freq = cpufreq_get(policy->cpu);
if (!cur_freq)
/**
* show_scaling_governor - show the current policy for the specified CPU
*/
-static ssize_t show_scaling_governor (struct cpufreq_policy * policy, char *buf)
+static ssize_t show_scaling_governor (struct cpufreq_policy * policy,
+ char *buf)
{
if(policy->policy == CPUFREQ_POLICY_POWERSAVE)
return sprintf(buf, "powersave\n");
/**
* 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 (ret != 1)
return -EINVAL;
- if (cpufreq_parse_governor(str_governor, &new_policy.policy, &new_policy.governor))
+ if (cpufreq_parse_governor(str_governor, &new_policy.policy,
+ &new_policy.governor))
return -EINVAL;
- ret = cpufreq_set_policy(&new_policy);
+ lock_cpu_hotplug();
- return ret ? ret : count;
+ /* 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();
+
+ if (ret)
+ return ret;
+ else
+ return count;
}
/**
/**
* show_scaling_available_governors - show the available CPUfreq governors
*/
-static ssize_t show_scaling_available_governors (struct cpufreq_policy * policy,
+static ssize_t show_scaling_available_governors (struct cpufreq_policy *policy,
char *buf)
{
ssize_t i = 0;
goto out;
i += scnprintf(&buf[i], CPUFREQ_NAME_LEN, "%s ", t->name);
}
- out:
+out:
i += sprintf(&buf[i], "\n");
return i;
}
policy = cpufreq_cpu_get(policy->cpu);
if (!policy)
return -EINVAL;
- ret = fattr->show ? fattr->show(policy,buf) : 0;
+ if (fattr->show)
+ ret = fattr->show(policy, buf);
+ else
+ ret = -EIO;
+
cpufreq_cpu_put(policy);
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);
policy = cpufreq_cpu_get(policy->cpu);
if (!policy)
return -EINVAL;
- ret = fattr->store ? fattr->store(policy,buf,count) : 0;
+ if (fattr->store)
+ ret = fattr->store(policy, buf, count);
+ else
+ ret = -EIO;
+
cpufreq_cpu_put(policy);
return ret;
}
/**
* 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;
cpufreq_debug_disable_ratelimit();
dprintk("adding CPU %u\n", cpu);
* CPU because it is in the same boat. */
policy = cpufreq_cpu_get(cpu);
if (unlikely(policy)) {
- cpu_sys_devices[cpu] = sys_dev;
- 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;
}
goto module_out;
}
- policy = kmalloc(sizeof(struct cpufreq_policy), GFP_KERNEL);
+ policy = kzalloc(sizeof(struct cpufreq_policy), GFP_KERNEL);
if (!policy) {
ret = -ENOMEM;
goto nomem_out;
}
- memset(policy, 0, sizeof(struct cpufreq_policy));
policy->cpu = cpu;
policy->cpus = cpumask_of_cpu(cpu);
- init_MUTEX_LOCKED(&policy->lock);
+ mutex_init(&policy->lock);
+ mutex_lock(&policy->lock);
init_completion(&policy->kobj_unregister);
- INIT_WORK(&policy->update, handle_update, (void *)(long)cpu);
+ INIT_WORK(&policy->update, handle_update);
/* call driver. From then on the cpufreq must be able
* to accept all calls to ->verify and ->setpolicy for this CPU
ret = cpufreq_driver->init(policy);
if (ret) {
dprintk("initialization failed\n");
+ mutex_unlock(&policy->lock);
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");
+ ret = sysfs_create_link(&sys_dev->kobj,
+ &managed_policy->kobj,
+ "cpufreq");
+ if (ret) {
+ mutex_unlock(&policy->lock);
+ goto err_out_driver_exit;
+ }
+
+ 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 */
strlcpy(policy->kobj.name, "cpufreq", KOBJ_NAME_LEN);
ret = kobject_register(&policy->kobj);
- if (ret)
- goto err_out;
-
+ if (ret) {
+ mutex_unlock(&policy->lock);
+ goto err_out_driver_exit;
+ }
/* set up files for this cpu device */
drv_attr = cpufreq_driver->attr;
while ((drv_attr) && (*drv_attr)) {
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);
+ ret = sysfs_create_link(&cpu_sys_dev->kobj, &policy->kobj,
+ "cpufreq");
+ if (ret) {
+ mutex_unlock(&policy->lock);
+ goto err_out_unregister;
+ }
+ }
+
policy->governor = NULL; /* to assure that the starting sequence is
* run in cpufreq_set_policy */
- up(&policy->lock);
-
+ 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);
- cpu_sys_devices[cpu] = sys_dev;
dprintk("initialization complete\n");
cpufreq_debug_enable_ratelimit();
-
+
return 0;
kobject_unregister(&policy->kobj);
wait_for_completion(&policy->kobj_unregister);
+err_out_driver_exit:
+ if (cpufreq_driver->exit)
+ cpufreq_driver->exit(policy);
+
err_out:
kfree(policy);
nomem_out:
module_put(cpufreq_driver->owner);
- module_out:
+module_out:
cpufreq_debug_enable_ratelimit();
return ret;
}
unsigned long flags;
struct cpufreq_policy *data;
#ifdef CONFIG_SMP
+ struct sys_device *cpu_sys_dev;
unsigned int j;
#endif
if (!data) {
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
- cpu_sys_devices[cpu] = NULL;
cpufreq_debug_enable_ratelimit();
return -EINVAL;
}
#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");
- cpu_sys_devices[cpu] = NULL;
cpufreq_cpu_put(data);
cpufreq_debug_enable_ratelimit();
return 0;
}
#endif
- cpu_sys_devices[cpu] = NULL;
if (!kobject_get(&data->kobj)) {
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
cpufreq_debug_enable_ratelimit();
- return -EFAULT;
+ return -EFAULT;
}
#ifdef CONFIG_SMP
if (j == cpu)
continue;
dprintk("removing link for cpu %u\n", j);
- sysfs_remove_link(&cpu_sys_devices[j]->kobj, "cpufreq");
+ cpu_sys_dev = get_cpu_sysdev(j);
+ sysfs_remove_link(&cpu_sys_dev->kobj, "cpufreq");
cpufreq_cpu_put(data);
}
}
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
#endif
- down(&data->lock);
+ mutex_lock(&data->lock);
if (cpufreq_driver->target)
__cpufreq_governor(data, CPUFREQ_GOV_STOP);
- cpufreq_driver->target = NULL;
- up(&data->lock);
+ mutex_unlock(&data->lock);
kobject_unregister(&data->kobj);
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");
kfree(data);
cpufreq_debug_enable_ratelimit();
-
return 0;
}
-static void handle_update(void *data)
+static void handle_update(struct work_struct *work)
{
- unsigned int cpu = (unsigned int)(long)data;
+ struct cpufreq_policy *policy =
+ container_of(work, struct cpufreq_policy, update);
+ unsigned int cpu = policy->cpu;
dprintk("handle_update for cpu %u called\n", cpu);
cpufreq_update_policy(cpu);
}
* We adjust to current frequency first, and need to clean up later. So either call
* to cpufreq_update_policy() or schedule handle_update()).
*/
-static void cpufreq_out_of_sync(unsigned int cpu, unsigned int old_freq, unsigned int new_freq)
+static void cpufreq_out_of_sync(unsigned int cpu, unsigned int old_freq,
+ unsigned int new_freq)
{
struct cpufreq_freqs freqs;
- printk(KERN_WARNING "Warning: CPU frequency out of sync: cpufreq and timing "
+ dprintk("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) from policy->cur
+ * @cpu: CPU number
+ *
+ * This is the last known freq, without actually getting it from the driver.
+ * Return value will be same as what is shown in scaling_cur_freq in sysfs.
+ */
+unsigned int cpufreq_quick_get(unsigned int cpu)
+{
+ struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+ unsigned int ret_freq = 0;
+
+ if (policy) {
+ mutex_lock(&policy->lock);
+ ret_freq = policy->cur;
+ mutex_unlock(&policy->lock);
+ cpufreq_cpu_put(policy);
+ }
+
+ return (ret_freq);
+}
+EXPORT_SYMBOL(cpufreq_quick_get);
+
+
+/**
* cpufreq_get - get the current CPU frequency (in kHz)
* @cpu: CPU number
*
unsigned int cpufreq_get(unsigned int cpu)
{
struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
- unsigned int ret = 0;
+ unsigned int ret_freq = 0;
if (!policy)
return 0;
if (!cpufreq_driver->get)
goto out;
- down(&policy->lock);
+ mutex_lock(&policy->lock);
- ret = cpufreq_driver->get(cpu);
+ ret_freq = cpufreq_driver->get(cpu);
- if (ret && policy->cur && !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS))
- {
- /* verify no discrepancy between actual and saved value exists */
- if (unlikely(ret != policy->cur)) {
- cpufreq_out_of_sync(cpu, policy->cur, ret);
+ if (ret_freq && policy->cur &&
+ !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
+ /* verify no discrepancy between actual and
+ saved value exists */
+ if (unlikely(ret_freq != policy->cur)) {
+ cpufreq_out_of_sync(cpu, policy->cur, ret_freq);
schedule_work(&policy->update);
}
}
- up(&policy->lock);
+ mutex_unlock(&policy->lock);
- out:
+out:
cpufreq_cpu_put(policy);
- return (ret);
+ return (ret_freq);
}
EXPORT_SYMBOL(cpufreq_get);
+/**
+ * cpufreq_suspend - let the low level driver prepare for suspend
+ */
+
+static int cpufreq_suspend(struct sys_device * sysdev, pm_message_t pmsg)
+{
+ int cpu = sysdev->id;
+ int ret = 0;
+ unsigned int cur_freq = 0;
+ struct cpufreq_policy *cpu_policy;
+
+ dprintk("suspending cpu %u\n", cpu);
+
+ if (!cpu_online(cpu))
+ return 0;
+
+ /* we may be lax here as interrupts are off. Nonetheless
+ * we need to grab the correct cpu policy, as to check
+ * whether we really run on this CPU.
+ */
+
+ cpu_policy = cpufreq_cpu_get(cpu);
+ if (!cpu_policy)
+ return -EINVAL;
+
+ /* only handle each CPU group once */
+ if (unlikely(cpu_policy->cpu != cpu)) {
+ cpufreq_cpu_put(cpu_policy);
+ return 0;
+ }
+
+ if (cpufreq_driver->suspend) {
+ ret = cpufreq_driver->suspend(cpu_policy, pmsg);
+ if (ret) {
+ printk(KERN_ERR "cpufreq: suspend failed in ->suspend "
+ "step on CPU %u\n", cpu_policy->cpu);
+ cpufreq_cpu_put(cpu_policy);
+ return ret;
+ }
+ }
+
+
+ if (cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)
+ goto out;
+
+ if (cpufreq_driver->get)
+ cur_freq = cpufreq_driver->get(cpu_policy->cpu);
+
+ if (!cur_freq || !cpu_policy->cur) {
+ printk(KERN_ERR "cpufreq: suspend failed to assert current "
+ "frequency is what timing core thinks it is.\n");
+ goto out;
+ }
+
+ if (unlikely(cur_freq != cpu_policy->cur)) {
+ struct cpufreq_freqs freqs;
+
+ if (!(cpufreq_driver->flags & CPUFREQ_PM_NO_WARN))
+ dprintk("Warning: CPU frequency is %u, "
+ "cpufreq assumed %u kHz.\n",
+ cur_freq, cpu_policy->cur);
+
+ freqs.cpu = cpu;
+ freqs.old = cpu_policy->cur;
+ freqs.new = cur_freq;
+
+ srcu_notifier_call_chain(&cpufreq_transition_notifier_list,
+ CPUFREQ_SUSPENDCHANGE, &freqs);
+ adjust_jiffies(CPUFREQ_SUSPENDCHANGE, &freqs);
+
+ cpu_policy->cur = cur_freq;
+ }
+
+out:
+ cpufreq_cpu_put(cpu_policy);
+ return 0;
+}
+
/**
* cpufreq_resume - restore proper CPU frequency handling after resume
*
* 1.) resume CPUfreq hardware support (cpufreq_driver->resume())
* 2.) if ->target and !CPUFREQ_CONST_LOOPS: verify we're in sync
- * 3.) schedule call cpufreq_update_policy() ASAP as interrupts are restored.
+ * 3.) schedule call cpufreq_update_policy() ASAP as interrupts are
+ * restored.
*/
static int cpufreq_resume(struct sys_device * sysdev)
{
int cpu = sysdev->id;
- unsigned int ret = 0;
+ int ret = 0;
struct cpufreq_policy *cpu_policy;
dprintk("resuming cpu %u\n", cpu);
cur_freq = cpufreq_driver->get(cpu_policy->cpu);
if (!cur_freq || !cpu_policy->cur) {
- printk(KERN_ERR "cpufreq: resume failed to assert current frequency is what timing core thinks it is.\n");
+ printk(KERN_ERR "cpufreq: resume failed to assert "
+ "current frequency is what timing core "
+ "thinks it is.\n");
goto out;
}
if (unlikely(cur_freq != cpu_policy->cur)) {
struct cpufreq_freqs freqs;
- printk(KERN_WARNING "Warning: CPU frequency is %u, "
- "cpufreq assumed %u kHz.\n", cur_freq, cpu_policy->cur);
+ if (!(cpufreq_driver->flags & CPUFREQ_PM_NO_WARN))
+ dprintk("Warning: CPU frequency"
+ "is %u, cpufreq assumed %u kHz.\n",
+ cur_freq, cpu_policy->cur);
freqs.cpu = cpu;
freqs.old = cpu_policy->cur;
freqs.new = cur_freq;
- notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_RESUMECHANGE, &freqs);
+ srcu_notifier_call_chain(
+ &cpufreq_transition_notifier_list,
+ CPUFREQ_RESUMECHANGE, &freqs);
adjust_jiffies(CPUFREQ_RESUMECHANGE, &freqs);
cpu_policy->cur = cur_freq;
static struct sysdev_driver cpufreq_sysdev_driver = {
.add = cpufreq_add_dev,
.remove = cpufreq_remove_dev,
+ .suspend = cpufreq_suspend,
.resume = cpufreq_resume,
};
* @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 = srcu_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;
}
* 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 = srcu_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;
}
*********************************************************************/
+/* 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);
-
int cpufreq_driver_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
- unsigned int ret;
+ int ret;
policy = cpufreq_cpu_get(policy->cpu);
if (!policy)
return -EINVAL;
- down(&policy->lock);
+ lock_cpu_hotplug();
+ mutex_lock(&policy->lock);
ret = __cpufreq_driver_target(policy, target_freq, relation);
- up(&policy->lock);
+ mutex_unlock(&policy->lock);
+ unlock_cpu_hotplug();
cpufreq_cpu_put(policy);
-
return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_driver_target);
-
-static int __cpufreq_governor(struct cpufreq_policy *policy, unsigned int event)
+int cpufreq_driver_getavg(struct cpufreq_policy *policy)
{
- int ret = -EINVAL;
+ int ret = 0;
- if (!try_module_get(policy->governor->owner))
+ policy = cpufreq_cpu_get(policy->cpu);
+ if (!policy)
return -EINVAL;
- dprintk("__cpufreq_governor for CPU %u, event %u\n", policy->cpu, event);
- ret = policy->governor->governor(policy, event);
+ mutex_lock(&policy->lock);
- /* we keep one module reference alive for each CPU governed by this CPU */
- if ((event != CPUFREQ_GOV_START) || ret)
- module_put(policy->governor->owner);
- if ((event == CPUFREQ_GOV_STOP) && !ret)
- module_put(policy->governor->owner);
+ if (cpu_online(policy->cpu) && cpufreq_driver->getavg)
+ ret = cpufreq_driver->getavg(policy->cpu);
+
+ mutex_unlock(&policy->lock);
+ cpufreq_cpu_put(policy);
return ret;
}
+EXPORT_SYMBOL_GPL(cpufreq_driver_getavg);
+/*
+ * Locking: Must be called with the lock_cpu_hotplug() lock held
+ * when "event" is CPUFREQ_GOV_LIMITS
+ */
-int cpufreq_governor(unsigned int cpu, unsigned int event)
+static int __cpufreq_governor(struct cpufreq_policy *policy,
+ unsigned int event)
{
- int ret = 0;
- struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+ int ret;
- if (!policy)
+ if (!try_module_get(policy->governor->owner))
return -EINVAL;
- down(&policy->lock);
- ret = __cpufreq_governor(policy, event);
- up(&policy->lock);
+ dprintk("__cpufreq_governor for CPU %u, event %u\n",
+ policy->cpu, event);
+ ret = policy->governor->governor(policy, event);
- cpufreq_cpu_put(policy);
+ /* we keep one module reference alive for
+ each CPU governed by this CPU */
+ if ((event != CPUFREQ_GOV_START) || ret)
+ module_put(policy->governor->owner);
+ if ((event == CPUFREQ_GOV_STOP) && !ret)
+ module_put(policy->governor->owner);
return ret;
}
-EXPORT_SYMBOL_GPL(cpufreq_governor);
int cpufreq_register_governor(struct cpufreq_governor *governor)
{
- struct cpufreq_governor *t;
+ int err;
if (!governor)
return -EINVAL;
- down(&cpufreq_governor_sem);
-
- list_for_each_entry(t, &cpufreq_governor_list, governor_list) {
- if (!strnicmp(governor->name,t->name,CPUFREQ_NAME_LEN)) {
- up(&cpufreq_governor_sem);
- return -EBUSY;
- }
- }
- list_add(&governor->governor_list, &cpufreq_governor_list);
+ mutex_lock(&cpufreq_governor_mutex);
- up(&cpufreq_governor_sem);
+ err = -EBUSY;
+ if (__find_governor(governor->name) == NULL) {
+ err = 0;
+ list_add(&governor->governor_list, &cpufreq_governor_list);
+ }
- return 0;
+ mutex_unlock(&cpufreq_governor_mutex);
+ return err;
}
EXPORT_SYMBOL_GPL(cpufreq_register_governor);
if (!governor)
return;
- down(&cpufreq_governor_sem);
+ mutex_lock(&cpufreq_governor_mutex);
list_del(&governor->governor_list);
- up(&cpufreq_governor_sem);
+ mutex_unlock(&cpufreq_governor_mutex);
return;
}
EXPORT_SYMBOL_GPL(cpufreq_unregister_governor);
if (!cpu_policy)
return -EINVAL;
- down(&cpu_policy->lock);
+ mutex_lock(&cpu_policy->lock);
memcpy(policy, cpu_policy, sizeof(struct cpufreq_policy));
- up(&cpu_policy->lock);
+ mutex_unlock(&cpu_policy->lock);
cpufreq_cpu_put(cpu_policy);
-
return 0;
}
EXPORT_SYMBOL(cpufreq_get_policy);
-static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_policy *policy)
+/*
+ * data : current policy.
+ * policy : policy to be set.
+ * 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;
dprintk("setting new policy for CPU %u: %u - %u kHz\n", policy->cpu,
policy->min, policy->max);
- memcpy(&policy->cpuinfo,
- &data->cpuinfo,
- sizeof(struct cpufreq_cpuinfo));
+ 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 */
- 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;
+ data->min = policy->min;
+ data->max = policy->max;
- dprintk("new min and max freqs are %u - %u kHz\n", data->min, data->max);
+ dprintk("new min and max freqs are %u - %u kHz\n",
+ data->min, data->max);
if (cpufreq_driver->setpolicy) {
data->policy = policy->policy;
data->governor = policy->governor;
if (__cpufreq_governor(data, CPUFREQ_GOV_START)) {
/* new governor failed, so re-start old one */
- dprintk("starting governor %s failed\n", data->governor->name);
+ dprintk("starting governor %s failed\n",
+ data->governor->name);
if (old_gov) {
data->governor = old_gov;
- __cpufreq_governor(data, CPUFREQ_GOV_START);
+ __cpufreq_governor(data,
+ CPUFREQ_GOV_START);
}
ret = -EINVAL;
goto error_out;
__cpufreq_governor(data, CPUFREQ_GOV_LIMITS);
}
- error_out:
+error_out:
cpufreq_debug_enable_ratelimit();
return ret;
}
if (!data)
return -EINVAL;
+ lock_cpu_hotplug();
+
/* lock this CPU */
- down(&data->lock);
+ mutex_lock(&data->lock);
ret = __cpufreq_set_policy(data, policy);
data->user_policy.min = data->min;
data->user_policy.policy = data->policy;
data->user_policy.governor = data->governor;
- up(&data->lock);
+ mutex_unlock(&data->lock);
+
+ unlock_cpu_hotplug();
cpufreq_cpu_put(data);
return ret;
if (!data)
return -ENODEV;
- down(&data->lock);
+ lock_cpu_hotplug();
+ mutex_lock(&data->lock);
dprintk("updating policy for CPU %u\n", cpu);
- memcpy(&policy,
- data,
- sizeof(struct cpufreq_policy));
+ memcpy(&policy, data, sizeof(struct cpufreq_policy));
policy.min = data->user_policy.min;
policy.max = data->user_policy.max;
policy.policy = data->user_policy.policy;
policy.governor = data->user_policy.governor;
- ret = __cpufreq_set_policy(data, &policy);
+ /* BIOS might change freq behind our back
+ -> ask driver for current freq and notify governors about a change */
+ if (cpufreq_driver->get) {
+ policy.cur = cpufreq_driver->get(cpu);
+ if (!data->cur) {
+ dprintk("Driver did not initialize current freq");
+ data->cur = policy.cur;
+ } else {
+ if (data->cur != policy.cur)
+ cpufreq_out_of_sync(cpu, data->cur,
+ policy.cur);
+ }
+ }
- up(&data->lock);
+ ret = __cpufreq_set_policy(data, &policy);
+ mutex_unlock(&data->lock);
+ unlock_cpu_hotplug();
cpufreq_cpu_put(data);
return ret;
}
EXPORT_SYMBOL(cpufreq_update_policy);
+static int cpufreq_cpu_callback(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ unsigned int cpu = (unsigned long)hcpu;
+ struct cpufreq_policy *policy;
+ struct sys_device *sys_dev;
+
+ sys_dev = get_cpu_sysdev(cpu);
+
+ if (sys_dev) {
+ switch (action) {
+ case CPU_ONLINE:
+ cpufreq_add_dev(sys_dev);
+ break;
+ case CPU_DOWN_PREPARE:
+ /*
+ * We attempt to put this cpu in lowest frequency
+ * possible before going down. This will permit
+ * hardware-managed P-State to switch other related
+ * threads to min or higher speeds if possible.
+ */
+ policy = cpufreq_cpu_data[cpu];
+ if (policy) {
+ cpufreq_driver_target(policy, policy->min,
+ CPUFREQ_RELATION_H);
+ }
+ break;
+ case CPU_DEAD:
+ cpufreq_remove_dev(sys_dev);
+ break;
+ }
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block __cpuinitdata cpufreq_cpu_notifier =
+{
+ .notifier_call = cpufreq_cpu_callback,
+};
/*********************************************************************
* 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 all ->init() calls failed, unregister */
if (ret) {
- dprintk("no CPU initialized for driver %s\n", driver_data->name);
- sysdev_driver_unregister(&cpu_sysdev_class, &cpufreq_sysdev_driver);
+ dprintk("no CPU initialized for driver %s\n",
+ driver_data->name);
+ sysdev_driver_unregister(&cpu_sysdev_class,
+ &cpufreq_sysdev_driver);
spin_lock_irqsave(&cpufreq_driver_lock, flags);
cpufreq_driver = NULL;
}
if (!ret) {
+ register_hotcpu_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);
spin_lock_irqsave(&cpufreq_driver_lock, flags);
cpufreq_driver = NULL;
git://git.onelab.eu / linux-2.6.git / blobdiff