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Diffstat (limited to 'drivers/cpufreq/cpufreq.c')
-rw-r--r--drivers/cpufreq/cpufreq.c166
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.