* (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
* 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);
/* internal prototypes */
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);
-static DEFINE_MUTEX (cpufreq_governor_mutex);
+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);
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
/**
- * 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)))
- {
- dprintk(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);
+ 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);
- if ((likely(cpufreq_cpu_data[freqs->cpu])) &&
- (likely(cpufreq_cpu_data[freqs->cpu]->cpu == freqs->cpu)))
- cpufreq_cpu_data[freqs->cpu]->cur = freqs->new;
+ 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);
return 0;
}
}
- out:
+out:
mutex_unlock(&cpufreq_governor_mutex);
}
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; \
\
- ret = cpufreq_set_policy(&new_policy); \
+ mutex_lock(&policy->lock); \
+ ret = __cpufreq_set_policy(policy, &new_policy); \
+ policy->user_policy.object = policy->object; \
+ mutex_unlock(&policy->lock); \
\
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;
- ret = cpufreq_set_policy(&new_policy);
+ /* 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);
return ret ? ret : count;
}
goto out;
i += scnprintf(&buf[i], CPUFREQ_NAME_LEN, "%s ", t->name);
}
- out:
+out:
i += sprintf(&buf[i], "\n");
return i;
}
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)) {
- 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 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");
kfree(data);
cpufreq_debug_enable_ratelimit();
-
return 0;
}
{
struct cpufreq_freqs freqs;
- dprintk(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) frpm policy->cur
* @cpu: CPU number
*
EXPORT_SYMBOL(cpufreq_quick_get);
-/**
+/**
* cpufreq_get - get the current CPU frequency (in kHz)
* @cpu: CPU number
*
ret = cpufreq_driver->get(cpu);
- if (ret && policy->cur && !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS))
- {
+ 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);
mutex_unlock(&policy->lock);
- out:
+out:
cpufreq_cpu_put(policy);
return (ret);
struct cpufreq_freqs freqs;
if (!(cpufreq_driver->flags & CPUFREQ_PM_NO_WARN))
- dprintk(KERN_DEBUG "Warning: CPU frequency is %u, "
+ dprintk("Warning: CPU frequency is %u, "
"cpufreq assumed %u kHz.\n",
cur_freq, cpu_policy->cur);
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);
cpu_policy->cur = cur_freq;
}
- out:
+out:
cpufreq_cpu_put(cpu_policy);
return 0;
}
struct cpufreq_freqs freqs;
if (!(cpufreq_driver->flags & CPUFREQ_PM_NO_WARN))
- dprintk(KERN_WARNING "Warning: CPU frequency"
+ dprintk("Warning: CPU frequency"
"is %u, cpufreq assumed %u kHz.\n",
cur_freq, cpu_policy->cur);
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);
* @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;
}
* 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;
}
mutex_unlock(&policy->lock);
cpufreq_cpu_put(policy);
-
return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_driver_target);
mutex_unlock(&policy->lock);
cpufreq_cpu_put(policy);
-
return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_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);
}
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);
mutex_unlock(&cpu_policy->lock);
cpufreq_cpu_put(cpu_policy);
-
return 0;
}
EXPORT_SYMBOL(cpufreq_get_policy);
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));
/* 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);
__cpufreq_governor(data, CPUFREQ_GOV_LIMITS);
}
- error_out:
+error_out:
cpufreq_debug_enable_ratelimit();
return ret;
}
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;
-> ask driver for current freq and notify governors about a change */
if (cpufreq_driver->get) {
policy.cur = cpufreq_driver->get(cpu);
- if (data->cur != policy.cur)
- cpufreq_out_of_sync(cpu, data->cur, policy.cur);
+ 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);
+ }
}
ret = __cpufreq_set_policy(data, &policy);
}
EXPORT_SYMBOL(cpufreq_update_policy);
-static int __cpuinit cpufreq_cpu_callback(struct notifier_block *nfb,
+static int cpufreq_cpu_callback(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
unsigned int cpu = (unsigned long)hcpu;
* @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)
/**
* 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.