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-rw-r--r--drivers/cpufreq/Kconfig2
-rw-r--r--drivers/cpufreq/cpufreq.c258
-rw-r--r--drivers/cpufreq/cpufreq_conservative.c2
-rw-r--r--drivers/cpufreq/cpufreq_ondemand.c64
-rw-r--r--drivers/cpufreq/cpufreq_stats.c2
-rw-r--r--drivers/cpufreq/cpufreq_userspace.c2
6 files changed, 213 insertions, 117 deletions
diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig
index 491779af8d55..d155e81b5c97 100644
--- a/drivers/cpufreq/Kconfig
+++ b/drivers/cpufreq/Kconfig
@@ -16,7 +16,7 @@ config CPU_FREQ
if CPU_FREQ
config CPU_FREQ_TABLE
- def_tristate m
+ tristate
config CPU_FREQ_DEBUG
bool "Enable CPUfreq debugging"
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index a45cc89e387a..f52facc570f5 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -41,8 +41,67 @@ static struct cpufreq_driver *cpufreq_driver;
static struct cpufreq_policy *cpufreq_cpu_data[NR_CPUS];
static DEFINE_SPINLOCK(cpufreq_driver_lock);
+/*
+ * cpu_policy_rwsem is a per CPU reader-writer semaphore designed to cure
+ * all cpufreq/hotplug/workqueue/etc related lock issues.
+ *
+ * The rules for this semaphore:
+ * - Any routine that wants to read from the policy structure will
+ * do a down_read on this semaphore.
+ * - Any routine that will write to the policy structure and/or may take away
+ * the policy altogether (eg. CPU hotplug), will hold this lock in write
+ * mode before doing so.
+ *
+ * Additional rules:
+ * - All holders of the lock should check to make sure that the CPU they
+ * are concerned with are online after they get the lock.
+ * - Governor routines that can be called in cpufreq hotplug path should not
+ * take this sem as top level hotplug notifier handler takes this.
+ */
+static DEFINE_PER_CPU(int, policy_cpu);
+static DEFINE_PER_CPU(struct rw_semaphore, cpu_policy_rwsem);
+
+#define lock_policy_rwsem(mode, cpu) \
+int lock_policy_rwsem_##mode \
+(int cpu) \
+{ \
+ int policy_cpu = per_cpu(policy_cpu, cpu); \
+ BUG_ON(policy_cpu == -1); \
+ down_##mode(&per_cpu(cpu_policy_rwsem, policy_cpu)); \
+ if (unlikely(!cpu_online(cpu))) { \
+ up_##mode(&per_cpu(cpu_policy_rwsem, policy_cpu)); \
+ return -1; \
+ } \
+ \
+ return 0; \
+}
+
+lock_policy_rwsem(read, cpu);
+EXPORT_SYMBOL_GPL(lock_policy_rwsem_read);
+
+lock_policy_rwsem(write, cpu);
+EXPORT_SYMBOL_GPL(lock_policy_rwsem_write);
+
+void unlock_policy_rwsem_read(int cpu)
+{
+ int policy_cpu = per_cpu(policy_cpu, cpu);
+ BUG_ON(policy_cpu == -1);
+ up_read(&per_cpu(cpu_policy_rwsem, policy_cpu));
+}
+EXPORT_SYMBOL_GPL(unlock_policy_rwsem_read);
+
+void unlock_policy_rwsem_write(int cpu)
+{
+ int policy_cpu = per_cpu(policy_cpu, cpu);
+ BUG_ON(policy_cpu == -1);
+ up_write(&per_cpu(cpu_policy_rwsem, policy_cpu));
+}
+EXPORT_SYMBOL_GPL(unlock_policy_rwsem_write);
+
+
/* internal prototypes */
static int __cpufreq_governor(struct cpufreq_policy *policy, unsigned int event);
+static unsigned int __cpufreq_get(unsigned int cpu);
static void handle_update(struct work_struct *work);
/**
@@ -415,12 +474,8 @@ static ssize_t store_##file_name \
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(); \
\
return ret ? ret : count; \
}
@@ -434,7 +489,7 @@ store_one(scaling_max_freq,max);
static ssize_t show_cpuinfo_cur_freq (struct cpufreq_policy * policy,
char *buf)
{
- unsigned int cur_freq = cpufreq_get(policy->cpu);
+ unsigned int cur_freq = __cpufreq_get(policy->cpu);
if (!cur_freq)
return sprintf(buf, "<unknown>");
return sprintf(buf, "%u\n", cur_freq);
@@ -479,18 +534,12 @@ static ssize_t store_scaling_governor (struct cpufreq_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();
if (ret)
return ret;
@@ -595,11 +644,17 @@ static ssize_t show(struct kobject * kobj, struct attribute * attr ,char * buf)
policy = cpufreq_cpu_get(policy->cpu);
if (!policy)
return -EINVAL;
+
+ if (lock_policy_rwsem_read(policy->cpu) < 0)
+ return -EINVAL;
+
if (fattr->show)
ret = fattr->show(policy, buf);
else
ret = -EIO;
+ unlock_policy_rwsem_read(policy->cpu);
+
cpufreq_cpu_put(policy);
return ret;
}
@@ -613,11 +668,17 @@ static ssize_t store(struct kobject * kobj, struct attribute * attr,
policy = cpufreq_cpu_get(policy->cpu);
if (!policy)
return -EINVAL;
+
+ if (lock_policy_rwsem_write(policy->cpu) < 0)
+ return -EINVAL;
+
if (fattr->store)
ret = fattr->store(policy, buf, count);
else
ret = -EIO;
+ unlock_policy_rwsem_write(policy->cpu);
+
cpufreq_cpu_put(policy);
return ret;
}
@@ -691,8 +752,10 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
policy->cpu = cpu;
policy->cpus = cpumask_of_cpu(cpu);
- mutex_init(&policy->lock);
- mutex_lock(&policy->lock);
+ /* Initially set CPU itself as the policy_cpu */
+ per_cpu(policy_cpu, cpu) = cpu;
+ lock_policy_rwsem_write(cpu);
+
init_completion(&policy->kobj_unregister);
INIT_WORK(&policy->update, handle_update);
@@ -702,7 +765,7 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
ret = cpufreq_driver->init(policy);
if (ret) {
dprintk("initialization failed\n");
- mutex_unlock(&policy->lock);
+ unlock_policy_rwsem_write(cpu);
goto err_out;
}
@@ -716,6 +779,14 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
*/
managed_policy = cpufreq_cpu_get(j);
if (unlikely(managed_policy)) {
+
+ /* Set proper policy_cpu */
+ unlock_policy_rwsem_write(cpu);
+ per_cpu(policy_cpu, cpu) = managed_policy->cpu;
+
+ if (lock_policy_rwsem_write(cpu) < 0)
+ goto err_out_driver_exit;
+
spin_lock_irqsave(&cpufreq_driver_lock, flags);
managed_policy->cpus = policy->cpus;
cpufreq_cpu_data[cpu] = managed_policy;
@@ -726,13 +797,13 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
&managed_policy->kobj,
"cpufreq");
if (ret) {
- mutex_unlock(&policy->lock);
+ unlock_policy_rwsem_write(cpu);
goto err_out_driver_exit;
}
cpufreq_debug_enable_ratelimit();
- mutex_unlock(&policy->lock);
ret = 0;
+ unlock_policy_rwsem_write(cpu);
goto err_out_driver_exit; /* call driver->exit() */
}
}
@@ -746,7 +817,7 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
ret = kobject_register(&policy->kobj);
if (ret) {
- mutex_unlock(&policy->lock);
+ unlock_policy_rwsem_write(cpu);
goto err_out_driver_exit;
}
/* set up files for this cpu device */
@@ -761,8 +832,10 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr);
spin_lock_irqsave(&cpufreq_driver_lock, flags);
- for_each_cpu_mask(j, policy->cpus)
+ for_each_cpu_mask(j, policy->cpus) {
cpufreq_cpu_data[j] = policy;
+ per_cpu(policy_cpu, j) = policy->cpu;
+ }
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
/* symlink affected CPUs */
@@ -778,14 +851,14 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
ret = sysfs_create_link(&cpu_sys_dev->kobj, &policy->kobj,
"cpufreq");
if (ret) {
- mutex_unlock(&policy->lock);
+ unlock_policy_rwsem_write(cpu);
goto err_out_unregister;
}
}
policy->governor = NULL; /* to assure that the starting sequence is
* run in cpufreq_set_policy */
- mutex_unlock(&policy->lock);
+ unlock_policy_rwsem_write(cpu);
/* set default policy */
ret = cpufreq_set_policy(&new_policy);
@@ -826,11 +899,13 @@ module_out:
/**
- * cpufreq_remove_dev - remove a CPU device
+ * __cpufreq_remove_dev - remove a CPU device
*
* Removes the cpufreq interface for a CPU device.
+ * Caller should already have policy_rwsem in write mode for this CPU.
+ * This routine frees the rwsem before returning.
*/
-static int cpufreq_remove_dev (struct sys_device * sys_dev)
+static int __cpufreq_remove_dev (struct sys_device * sys_dev)
{
unsigned int cpu = sys_dev->id;
unsigned long flags;
@@ -849,6 +924,7 @@ static int cpufreq_remove_dev (struct sys_device * sys_dev)
if (!data) {
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
cpufreq_debug_enable_ratelimit();
+ unlock_policy_rwsem_write(cpu);
return -EINVAL;
}
cpufreq_cpu_data[cpu] = NULL;
@@ -865,6 +941,7 @@ static int cpufreq_remove_dev (struct sys_device * sys_dev)
sysfs_remove_link(&sys_dev->kobj, "cpufreq");
cpufreq_cpu_put(data);
cpufreq_debug_enable_ratelimit();
+ unlock_policy_rwsem_write(cpu);
return 0;
}
#endif
@@ -873,6 +950,7 @@ 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();
+ unlock_policy_rwsem_write(cpu);
return -EFAULT;
}
@@ -906,10 +984,10 @@ static int cpufreq_remove_dev (struct sys_device * sys_dev)
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
#endif
- mutex_lock(&data->lock);
if (cpufreq_driver->target)
__cpufreq_governor(data, CPUFREQ_GOV_STOP);
- mutex_unlock(&data->lock);
+
+ unlock_policy_rwsem_write(cpu);
kobject_unregister(&data->kobj);
@@ -933,6 +1011,18 @@ static int cpufreq_remove_dev (struct sys_device * sys_dev)
}
+static int cpufreq_remove_dev (struct sys_device * sys_dev)
+{
+ unsigned int cpu = sys_dev->id;
+ int retval;
+ if (unlikely(lock_policy_rwsem_write(cpu)))
+ BUG();
+
+ retval = __cpufreq_remove_dev(sys_dev);
+ return retval;
+}
+
+
static void handle_update(struct work_struct *work)
{
struct cpufreq_policy *policy =
@@ -980,9 +1070,12 @@ unsigned int cpufreq_quick_get(unsigned int cpu)
unsigned int ret_freq = 0;
if (policy) {
- mutex_lock(&policy->lock);
+ if (unlikely(lock_policy_rwsem_read(cpu)))
+ return ret_freq;
+
ret_freq = policy->cur;
- mutex_unlock(&policy->lock);
+
+ unlock_policy_rwsem_read(cpu);
cpufreq_cpu_put(policy);
}
@@ -991,24 +1084,13 @@ 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
- *
- * Get the CPU current (static) CPU frequency
- */
-unsigned int cpufreq_get(unsigned int cpu)
+static unsigned int __cpufreq_get(unsigned int cpu)
{
- struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+ struct cpufreq_policy *policy = cpufreq_cpu_data[cpu];
unsigned int ret_freq = 0;
- if (!policy)
- return 0;
-
if (!cpufreq_driver->get)
- goto out;
-
- mutex_lock(&policy->lock);
+ return (ret_freq);
ret_freq = cpufreq_driver->get(cpu);
@@ -1022,11 +1104,33 @@ unsigned int cpufreq_get(unsigned int cpu)
}
}
- mutex_unlock(&policy->lock);
+ return (ret_freq);
+}
-out:
- cpufreq_cpu_put(policy);
+/**
+ * cpufreq_get - get the current CPU frequency (in kHz)
+ * @cpu: CPU number
+ *
+ * Get the CPU current (static) CPU frequency
+ */
+unsigned int cpufreq_get(unsigned int cpu)
+{
+ unsigned int ret_freq = 0;
+ struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+
+ if (!policy)
+ goto out;
+
+ if (unlikely(lock_policy_rwsem_read(cpu)))
+ goto out_policy;
+
+ ret_freq = __cpufreq_get(cpu);
+ unlock_policy_rwsem_read(cpu);
+
+out_policy:
+ cpufreq_cpu_put(policy);
+out:
return (ret_freq);
}
EXPORT_SYMBOL(cpufreq_get);
@@ -1278,7 +1382,6 @@ EXPORT_SYMBOL(cpufreq_unregister_notifier);
*********************************************************************/
-/* Must be called with lock_cpu_hotplug held */
int __cpufreq_driver_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
@@ -1304,20 +1407,19 @@ int cpufreq_driver_target(struct cpufreq_policy *policy,
if (!policy)
return -EINVAL;
- lock_cpu_hotplug();
- mutex_lock(&policy->lock);
+ if (unlikely(lock_policy_rwsem_write(policy->cpu)))
+ return -EINVAL;
ret = __cpufreq_driver_target(policy, target_freq, relation);
- mutex_unlock(&policy->lock);
- unlock_cpu_hotplug();
+ unlock_policy_rwsem_write(policy->cpu);
cpufreq_cpu_put(policy);
return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_driver_target);
-int cpufreq_driver_getavg(struct cpufreq_policy *policy)
+int __cpufreq_driver_getavg(struct cpufreq_policy *policy)
{
int ret = 0;
@@ -1325,20 +1427,15 @@ int cpufreq_driver_getavg(struct cpufreq_policy *policy)
if (!policy)
return -EINVAL;
- mutex_lock(&policy->lock);
-
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);
+EXPORT_SYMBOL_GPL(__cpufreq_driver_getavg);
/*
- * Locking: Must be called with the lock_cpu_hotplug() lock held
* when "event" is CPUFREQ_GOV_LIMITS
*/
@@ -1420,9 +1517,7 @@ int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu)
if (!cpu_policy)
return -EINVAL;
- mutex_lock(&cpu_policy->lock);
memcpy(policy, cpu_policy, sizeof(struct cpufreq_policy));
- mutex_unlock(&cpu_policy->lock);
cpufreq_cpu_put(cpu_policy);
return 0;
@@ -1433,7 +1528,6 @@ EXPORT_SYMBOL(cpufreq_get_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)
@@ -1539,10 +1633,9 @@ int cpufreq_set_policy(struct cpufreq_policy *policy)
if (!data)
return -EINVAL;
- lock_cpu_hotplug();
+ if (unlikely(lock_policy_rwsem_write(policy->cpu)))
+ return -EINVAL;
- /* lock this CPU */
- mutex_lock(&data->lock);
ret = __cpufreq_set_policy(data, policy);
data->user_policy.min = data->min;
@@ -1550,9 +1643,8 @@ int cpufreq_set_policy(struct cpufreq_policy *policy)
data->user_policy.policy = data->policy;
data->user_policy.governor = data->governor;
- mutex_unlock(&data->lock);
+ unlock_policy_rwsem_write(policy->cpu);
- unlock_cpu_hotplug();
cpufreq_cpu_put(data);
return ret;
@@ -1576,8 +1668,8 @@ int cpufreq_update_policy(unsigned int cpu)
if (!data)
return -ENODEV;
- lock_cpu_hotplug();
- mutex_lock(&data->lock);
+ if (unlikely(lock_policy_rwsem_write(cpu)))
+ return -EINVAL;
dprintk("updating policy for CPU %u\n", cpu);
memcpy(&policy, data, sizeof(struct cpufreq_policy));
@@ -1602,8 +1694,8 @@ int cpufreq_update_policy(unsigned int cpu)
ret = __cpufreq_set_policy(data, &policy);
- mutex_unlock(&data->lock);
- unlock_cpu_hotplug();
+ unlock_policy_rwsem_write(cpu);
+
cpufreq_cpu_put(data);
return ret;
}
@@ -1613,31 +1705,28 @@ 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;
+ struct cpufreq_policy *policy;
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.
- */
+ if (unlikely(lock_policy_rwsem_write(cpu)))
+ BUG();
+
policy = cpufreq_cpu_data[cpu];
if (policy) {
- cpufreq_driver_target(policy, policy->min,
+ __cpufreq_driver_target(policy, policy->min,
CPUFREQ_RELATION_H);
}
+ __cpufreq_remove_dev(sys_dev);
break;
- case CPU_DEAD:
- cpufreq_remove_dev(sys_dev);
+ case CPU_DOWN_FAILED:
+ cpufreq_add_dev(sys_dev);
break;
}
}
@@ -1751,3 +1840,16 @@ int cpufreq_unregister_driver(struct cpufreq_driver *driver)
return 0;
}
EXPORT_SYMBOL_GPL(cpufreq_unregister_driver);
+
+static int __init cpufreq_core_init(void)
+{
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ per_cpu(policy_cpu, cpu) = -1;
+ init_rwsem(&per_cpu(cpu_policy_rwsem, cpu));
+ }
+ return 0;
+}
+
+core_initcall(cpufreq_core_init);
diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c
index 05d6c22ba07c..26f440ccc3fb 100644
--- a/drivers/cpufreq/cpufreq_conservative.c
+++ b/drivers/cpufreq/cpufreq_conservative.c
@@ -429,14 +429,12 @@ static void dbs_check_cpu(int cpu)
static void do_dbs_timer(struct work_struct *work)
{
int i;
- lock_cpu_hotplug();
mutex_lock(&dbs_mutex);
for_each_online_cpu(i)
dbs_check_cpu(i);
schedule_delayed_work(&dbs_work,
usecs_to_jiffies(dbs_tuners_ins.sampling_rate));
mutex_unlock(&dbs_mutex);
- unlock_cpu_hotplug();
}
static inline void dbs_timer_init(void)
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
index f697449327c6..d60bcb9d14cc 100644
--- a/drivers/cpufreq/cpufreq_ondemand.c
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -52,19 +52,20 @@ static unsigned int def_sampling_rate;
static void do_dbs_timer(struct work_struct *work);
/* Sampling types */
-enum dbs_sample {DBS_NORMAL_SAMPLE, DBS_SUB_SAMPLE};
+enum {DBS_NORMAL_SAMPLE, DBS_SUB_SAMPLE};
struct cpu_dbs_info_s {
cputime64_t prev_cpu_idle;
cputime64_t prev_cpu_wall;
struct cpufreq_policy *cur_policy;
struct delayed_work work;
- enum dbs_sample sample_type;
- unsigned int enable;
struct cpufreq_frequency_table *freq_table;
unsigned int freq_lo;
unsigned int freq_lo_jiffies;
unsigned int freq_hi_jiffies;
+ int cpu;
+ unsigned int enable:1,
+ sample_type:1;
};
static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info);
@@ -402,7 +403,7 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
if (load < (dbs_tuners_ins.up_threshold - 10)) {
unsigned int freq_next, freq_cur;
- freq_cur = cpufreq_driver_getavg(policy);
+ freq_cur = __cpufreq_driver_getavg(policy);
if (!freq_cur)
freq_cur = policy->cur;
@@ -423,9 +424,11 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
static void do_dbs_timer(struct work_struct *work)
{
- unsigned int cpu = smp_processor_id();
- struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, cpu);
- enum dbs_sample sample_type = dbs_info->sample_type;
+ struct cpu_dbs_info_s *dbs_info =
+ container_of(work, struct cpu_dbs_info_s, work.work);
+ unsigned int cpu = dbs_info->cpu;
+ int sample_type = dbs_info->sample_type;
+
/* We want all CPUs to do sampling nearly on same jiffy */
int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate);
@@ -434,15 +437,19 @@ static void do_dbs_timer(struct work_struct *work)
delay -= jiffies % delay;
- if (!dbs_info->enable)
+ if (lock_policy_rwsem_write(cpu) < 0)
+ return;
+
+ if (!dbs_info->enable) {
+ unlock_policy_rwsem_write(cpu);
return;
+ }
+
/* Common NORMAL_SAMPLE setup */
dbs_info->sample_type = DBS_NORMAL_SAMPLE;
if (!dbs_tuners_ins.powersave_bias ||
sample_type == DBS_NORMAL_SAMPLE) {
- lock_cpu_hotplug();
dbs_check_cpu(dbs_info);
- unlock_cpu_hotplug();
if (dbs_info->freq_lo) {
/* Setup timer for SUB_SAMPLE */
dbs_info->sample_type = DBS_SUB_SAMPLE;
@@ -454,26 +461,27 @@ static void do_dbs_timer(struct work_struct *work)
CPUFREQ_RELATION_H);
}
queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work, delay);
+ unlock_policy_rwsem_write(cpu);
}
-static inline void dbs_timer_init(unsigned int cpu)
+static inline void dbs_timer_init(struct cpu_dbs_info_s *dbs_info)
{
- struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, cpu);
/* We want all CPUs to do sampling nearly on same jiffy */
int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate);
delay -= jiffies % delay;
+ dbs_info->enable = 1;
ondemand_powersave_bias_init();
- INIT_DELAYED_WORK_NAR(&dbs_info->work, do_dbs_timer);
dbs_info->sample_type = DBS_NORMAL_SAMPLE;
- queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work, delay);
+ INIT_DELAYED_WORK_NAR(&dbs_info->work, do_dbs_timer);
+ queue_delayed_work_on(dbs_info->cpu, kondemand_wq, &dbs_info->work,
+ delay);
}
static inline void dbs_timer_exit(struct cpu_dbs_info_s *dbs_info)
{
dbs_info->enable = 0;
cancel_delayed_work(&dbs_info->work);
- flush_workqueue(kondemand_wq);
}
static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
@@ -502,21 +510,9 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
mutex_lock(&dbs_mutex);
dbs_enable++;
- if (dbs_enable == 1) {
- kondemand_wq = create_workqueue("kondemand");
- if (!kondemand_wq) {
- printk(KERN_ERR
- "Creation of kondemand failed\n");
- dbs_enable--;
- mutex_unlock(&dbs_mutex);
- return -ENOSPC;
- }
- }
rc = sysfs_create_group(&policy->kobj, &dbs_attr_group);
if (rc) {
- if (dbs_enable == 1)
- destroy_workqueue(kondemand_wq);
dbs_enable--;
mutex_unlock(&dbs_mutex);
return rc;
@@ -530,7 +526,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
j_dbs_info->prev_cpu_idle = get_cpu_idle_time(j);
j_dbs_info->prev_cpu_wall = get_jiffies_64();
}
- this_dbs_info->enable = 1;
+ this_dbs_info->cpu = cpu;
/*
* Start the timerschedule work, when this governor
* is used for first time
@@ -550,7 +546,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
dbs_tuners_ins.sampling_rate = def_sampling_rate;
}
- dbs_timer_init(policy->cpu);
+ dbs_timer_init(this_dbs_info);
mutex_unlock(&dbs_mutex);
break;
@@ -560,9 +556,6 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
dbs_timer_exit(this_dbs_info);
sysfs_remove_group(&policy->kobj, &dbs_attr_group);
dbs_enable--;
- if (dbs_enable == 0)
- destroy_workqueue(kondemand_wq);
-
mutex_unlock(&dbs_mutex);
break;
@@ -591,12 +584,18 @@ static struct cpufreq_governor cpufreq_gov_dbs = {
static int __init cpufreq_gov_dbs_init(void)
{
+ kondemand_wq = create_workqueue("kondemand");
+ if (!kondemand_wq) {
+ printk(KERN_ERR "Creation of kondemand failed\n");
+ return -EFAULT;
+ }
return cpufreq_register_governor(&cpufreq_gov_dbs);
}
static void __exit cpufreq_gov_dbs_exit(void)
{
cpufreq_unregister_governor(&cpufreq_gov_dbs);
+ destroy_workqueue(kondemand_wq);
}
@@ -608,3 +607,4 @@ MODULE_LICENSE("GPL");
module_init(cpufreq_gov_dbs_init);
module_exit(cpufreq_gov_dbs_exit);
+
diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
index 91ad342a6051..d1c7cac9316c 100644
--- a/drivers/cpufreq/cpufreq_stats.c
+++ b/drivers/cpufreq/cpufreq_stats.c
@@ -370,12 +370,10 @@ __exit cpufreq_stats_exit(void)
cpufreq_unregister_notifier(&notifier_trans_block,
CPUFREQ_TRANSITION_NOTIFIER);
unregister_hotcpu_notifier(&cpufreq_stat_cpu_notifier);
- lock_cpu_hotplug();
for_each_online_cpu(cpu) {
cpufreq_stat_cpu_callback(&cpufreq_stat_cpu_notifier,
CPU_DEAD, (void *)(long)cpu);
}
- unlock_cpu_hotplug();
}
MODULE_AUTHOR ("Zou Nan hai <nanhai.zou@intel.com>");
diff --git a/drivers/cpufreq/cpufreq_userspace.c b/drivers/cpufreq/cpufreq_userspace.c
index 2a4eb0bfaf30..860345c7799a 100644
--- a/drivers/cpufreq/cpufreq_userspace.c
+++ b/drivers/cpufreq/cpufreq_userspace.c
@@ -71,7 +71,6 @@ static int cpufreq_set(unsigned int freq, struct cpufreq_policy *policy)
dprintk("cpufreq_set for cpu %u, freq %u kHz\n", policy->cpu, freq);
- lock_cpu_hotplug();
mutex_lock(&userspace_mutex);
if (!cpu_is_managed[policy->cpu])
goto err;
@@ -94,7 +93,6 @@ static int cpufreq_set(unsigned int freq, struct cpufreq_policy *policy)
err:
mutex_unlock(&userspace_mutex);
- unlock_cpu_hotplug();
return ret;
}