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path: root/drivers/cpufreq/cpufreq_governor.c
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Diffstat (limited to 'drivers/cpufreq/cpufreq_governor.c')
-rw-r--r--drivers/cpufreq/cpufreq_governor.c760
1 files changed, 398 insertions, 362 deletions
diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c
index e0d111024..5f1147fa9 100644
--- a/drivers/cpufreq/cpufreq_governor.c
+++ b/drivers/cpufreq/cpufreq_governor.c
@@ -18,95 +18,189 @@
#include <linux/export.h>
#include <linux/kernel_stat.h>
+#include <linux/sched.h>
#include <linux/slab.h>
#include "cpufreq_governor.h"
-static struct attribute_group *get_sysfs_attr(struct dbs_data *dbs_data)
-{
- if (have_governor_per_policy())
- return dbs_data->cdata->attr_group_gov_pol;
- else
- return dbs_data->cdata->attr_group_gov_sys;
-}
+static DEFINE_PER_CPU(struct cpu_dbs_info, cpu_dbs);
+
+static DEFINE_MUTEX(gov_dbs_data_mutex);
-void dbs_check_cpu(struct dbs_data *dbs_data, int cpu)
+/* Common sysfs tunables */
+/**
+ * store_sampling_rate - update sampling rate effective immediately if needed.
+ *
+ * If new rate is smaller than the old, simply updating
+ * dbs.sampling_rate might not be appropriate. For example, if the
+ * original sampling_rate was 1 second and the requested new sampling rate is 10
+ * ms because the user needs immediate reaction from ondemand governor, but not
+ * sure if higher frequency will be required or not, then, the governor may
+ * change the sampling rate too late; up to 1 second later. Thus, if we are
+ * reducing the sampling rate, we need to make the new value effective
+ * immediately.
+ *
+ * This must be called with dbs_data->mutex held, otherwise traversing
+ * policy_dbs_list isn't safe.
+ */
+ssize_t store_sampling_rate(struct dbs_data *dbs_data, const char *buf,
+ size_t count)
{
- struct cpu_dbs_info *cdbs = dbs_data->cdata->get_cpu_cdbs(cpu);
- struct od_dbs_tuners *od_tuners = dbs_data->tuners;
- struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
- struct cpufreq_policy *policy = cdbs->shared->policy;
- unsigned int sampling_rate;
- unsigned int max_load = 0;
- unsigned int ignore_nice;
- unsigned int j;
+ struct policy_dbs_info *policy_dbs;
+ unsigned int rate;
+ int ret;
+ ret = sscanf(buf, "%u", &rate);
+ if (ret != 1)
+ return -EINVAL;
- if (dbs_data->cdata->governor == GOV_ONDEMAND) {
- struct od_cpu_dbs_info_s *od_dbs_info =
- dbs_data->cdata->get_cpu_dbs_info_s(cpu);
+ dbs_data->sampling_rate = max(rate, dbs_data->min_sampling_rate);
+ /*
+ * We are operating under dbs_data->mutex and so the list and its
+ * entries can't be freed concurrently.
+ */
+ list_for_each_entry(policy_dbs, &dbs_data->policy_dbs_list, list) {
+ mutex_lock(&policy_dbs->timer_mutex);
/*
- * Sometimes, the ondemand governor uses an additional
- * multiplier to give long delays. So apply this multiplier to
- * the 'sampling_rate', so as to keep the wake-up-from-idle
- * detection logic a bit conservative.
+ * On 32-bit architectures this may race with the
+ * sample_delay_ns read in dbs_update_util_handler(), but that
+ * really doesn't matter. If the read returns a value that's
+ * too big, the sample will be skipped, but the next invocation
+ * of dbs_update_util_handler() (when the update has been
+ * completed) will take a sample.
+ *
+ * If this runs in parallel with dbs_work_handler(), we may end
+ * up overwriting the sample_delay_ns value that it has just
+ * written, but it will be corrected next time a sample is
+ * taken, so it shouldn't be significant.
*/
- sampling_rate = od_tuners->sampling_rate;
- sampling_rate *= od_dbs_info->rate_mult;
+ gov_update_sample_delay(policy_dbs, 0);
+ mutex_unlock(&policy_dbs->timer_mutex);
+ }
- ignore_nice = od_tuners->ignore_nice_load;
- } else {
- sampling_rate = cs_tuners->sampling_rate;
- ignore_nice = cs_tuners->ignore_nice_load;
+ return count;
+}
+EXPORT_SYMBOL_GPL(store_sampling_rate);
+
+/**
+ * gov_update_cpu_data - Update CPU load data.
+ * @dbs_data: Top-level governor data pointer.
+ *
+ * Update CPU load data for all CPUs in the domain governed by @dbs_data
+ * (that may be a single policy or a bunch of them if governor tunables are
+ * system-wide).
+ *
+ * Call under the @dbs_data mutex.
+ */
+void gov_update_cpu_data(struct dbs_data *dbs_data)
+{
+ struct policy_dbs_info *policy_dbs;
+
+ list_for_each_entry(policy_dbs, &dbs_data->policy_dbs_list, list) {
+ unsigned int j;
+
+ for_each_cpu(j, policy_dbs->policy->cpus) {
+ struct cpu_dbs_info *j_cdbs = &per_cpu(cpu_dbs, j);
+
+ j_cdbs->prev_cpu_idle = get_cpu_idle_time(j, &j_cdbs->prev_cpu_wall,
+ dbs_data->io_is_busy);
+ if (dbs_data->ignore_nice_load)
+ j_cdbs->prev_cpu_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE];
+ }
}
+}
+EXPORT_SYMBOL_GPL(gov_update_cpu_data);
+
+static inline struct dbs_data *to_dbs_data(struct kobject *kobj)
+{
+ return container_of(kobj, struct dbs_data, kobj);
+}
+
+static inline struct governor_attr *to_gov_attr(struct attribute *attr)
+{
+ return container_of(attr, struct governor_attr, attr);
+}
+
+static ssize_t governor_show(struct kobject *kobj, struct attribute *attr,
+ char *buf)
+{
+ struct dbs_data *dbs_data = to_dbs_data(kobj);
+ struct governor_attr *gattr = to_gov_attr(attr);
+
+ return gattr->show(dbs_data, buf);
+}
+
+static ssize_t governor_store(struct kobject *kobj, struct attribute *attr,
+ const char *buf, size_t count)
+{
+ struct dbs_data *dbs_data = to_dbs_data(kobj);
+ struct governor_attr *gattr = to_gov_attr(attr);
+ int ret = -EBUSY;
+
+ mutex_lock(&dbs_data->mutex);
+
+ if (dbs_data->usage_count)
+ ret = gattr->store(dbs_data, buf, count);
+
+ mutex_unlock(&dbs_data->mutex);
+
+ return ret;
+}
+
+/*
+ * Sysfs Ops for accessing governor attributes.
+ *
+ * All show/store invocations for governor specific sysfs attributes, will first
+ * call the below show/store callbacks and the attribute specific callback will
+ * be called from within it.
+ */
+static const struct sysfs_ops governor_sysfs_ops = {
+ .show = governor_show,
+ .store = governor_store,
+};
+
+unsigned int dbs_update(struct cpufreq_policy *policy)
+{
+ struct policy_dbs_info *policy_dbs = policy->governor_data;
+ struct dbs_data *dbs_data = policy_dbs->dbs_data;
+ unsigned int ignore_nice = dbs_data->ignore_nice_load;
+ unsigned int max_load = 0;
+ unsigned int sampling_rate, io_busy, j;
+
+ /*
+ * Sometimes governors may use an additional multiplier to increase
+ * sample delays temporarily. Apply that multiplier to sampling_rate
+ * so as to keep the wake-up-from-idle detection logic a bit
+ * conservative.
+ */
+ sampling_rate = dbs_data->sampling_rate * policy_dbs->rate_mult;
+ /*
+ * For the purpose of ondemand, waiting for disk IO is an indication
+ * that you're performance critical, and not that the system is actually
+ * idle, so do not add the iowait time to the CPU idle time then.
+ */
+ io_busy = dbs_data->io_is_busy;
/* Get Absolute Load */
for_each_cpu(j, policy->cpus) {
- struct cpu_dbs_info *j_cdbs;
+ struct cpu_dbs_info *j_cdbs = &per_cpu(cpu_dbs, j);
u64 cur_wall_time, cur_idle_time;
unsigned int idle_time, wall_time;
unsigned int load;
- int io_busy = 0;
- j_cdbs = dbs_data->cdata->get_cpu_cdbs(j);
-
- /*
- * For the purpose of ondemand, waiting for disk IO is
- * an indication that you're performance critical, and
- * not that the system is actually idle. So do not add
- * the iowait time to the cpu idle time.
- */
- if (dbs_data->cdata->governor == GOV_ONDEMAND)
- io_busy = od_tuners->io_is_busy;
cur_idle_time = get_cpu_idle_time(j, &cur_wall_time, io_busy);
- wall_time = (unsigned int)
- (cur_wall_time - j_cdbs->prev_cpu_wall);
+ wall_time = cur_wall_time - j_cdbs->prev_cpu_wall;
j_cdbs->prev_cpu_wall = cur_wall_time;
- if (cur_idle_time < j_cdbs->prev_cpu_idle)
- cur_idle_time = j_cdbs->prev_cpu_idle;
-
- idle_time = (unsigned int)
- (cur_idle_time - j_cdbs->prev_cpu_idle);
+ idle_time = cur_idle_time - j_cdbs->prev_cpu_idle;
j_cdbs->prev_cpu_idle = cur_idle_time;
if (ignore_nice) {
- u64 cur_nice;
- unsigned long cur_nice_jiffies;
-
- cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE] -
- cdbs->prev_cpu_nice;
- /*
- * Assumption: nice time between sampling periods will
- * be less than 2^32 jiffies for 32 bit sys
- */
- cur_nice_jiffies = (unsigned long)
- cputime64_to_jiffies64(cur_nice);
+ u64 cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE];
- cdbs->prev_cpu_nice =
- kcpustat_cpu(j).cpustat[CPUTIME_NICE];
- idle_time += jiffies_to_usecs(cur_nice_jiffies);
+ idle_time += cputime_to_usecs(cur_nice - j_cdbs->prev_cpu_nice);
+ j_cdbs->prev_cpu_nice = cur_nice;
}
if (unlikely(!wall_time || wall_time < idle_time))
@@ -128,10 +222,10 @@ void dbs_check_cpu(struct dbs_data *dbs_data, int cpu)
* dropped down. So we perform the copy only once, upon the
* first wake-up from idle.)
*
- * Detecting this situation is easy: the governor's deferrable
- * timer would not have fired during CPU-idle periods. Hence
- * an unusually large 'wall_time' (as compared to the sampling
- * rate) indicates this scenario.
+ * Detecting this situation is easy: the governor's utilization
+ * update handler would not have run during CPU-idle periods.
+ * Hence, an unusually large 'wall_time' (as compared to the
+ * sampling rate) indicates this scenario.
*
* prev_load can be zero in two cases and we must recalculate it
* for both cases:
@@ -156,222 +250,224 @@ void dbs_check_cpu(struct dbs_data *dbs_data, int cpu)
if (load > max_load)
max_load = load;
}
-
- dbs_data->cdata->gov_check_cpu(cpu, max_load);
+ return max_load;
}
-EXPORT_SYMBOL_GPL(dbs_check_cpu);
+EXPORT_SYMBOL_GPL(dbs_update);
-void gov_add_timers(struct cpufreq_policy *policy, unsigned int delay)
+static void gov_set_update_util(struct policy_dbs_info *policy_dbs,
+ unsigned int delay_us)
{
- struct dbs_data *dbs_data = policy->governor_data;
- struct cpu_dbs_info *cdbs;
+ struct cpufreq_policy *policy = policy_dbs->policy;
int cpu;
+ gov_update_sample_delay(policy_dbs, delay_us);
+ policy_dbs->last_sample_time = 0;
+
for_each_cpu(cpu, policy->cpus) {
- cdbs = dbs_data->cdata->get_cpu_cdbs(cpu);
- cdbs->timer.expires = jiffies + delay;
- add_timer_on(&cdbs->timer, cpu);
+ struct cpu_dbs_info *cdbs = &per_cpu(cpu_dbs, cpu);
+
+ cpufreq_set_update_util_data(cpu, &cdbs->update_util);
}
}
-EXPORT_SYMBOL_GPL(gov_add_timers);
-static inline void gov_cancel_timers(struct cpufreq_policy *policy)
+static inline void gov_clear_update_util(struct cpufreq_policy *policy)
{
- struct dbs_data *dbs_data = policy->governor_data;
- struct cpu_dbs_info *cdbs;
int i;
- for_each_cpu(i, policy->cpus) {
- cdbs = dbs_data->cdata->get_cpu_cdbs(i);
- del_timer_sync(&cdbs->timer);
- }
-}
+ for_each_cpu(i, policy->cpus)
+ cpufreq_set_update_util_data(i, NULL);
-void gov_cancel_work(struct cpu_common_dbs_info *shared)
-{
- /* Tell dbs_timer_handler() to skip queuing up work items. */
- atomic_inc(&shared->skip_work);
- /*
- * If dbs_timer_handler() is already running, it may not notice the
- * incremented skip_work, so wait for it to complete to prevent its work
- * item from being queued up after the cancel_work_sync() below.
- */
- gov_cancel_timers(shared->policy);
- /*
- * In case dbs_timer_handler() managed to run and spawn a work item
- * before the timers have been canceled, wait for that work item to
- * complete and then cancel all of the timers set up by it. If
- * dbs_timer_handler() runs again at that point, it will see the
- * positive value of skip_work and won't spawn any more work items.
- */
- cancel_work_sync(&shared->work);
- gov_cancel_timers(shared->policy);
- atomic_set(&shared->skip_work, 0);
+ synchronize_sched();
}
-EXPORT_SYMBOL_GPL(gov_cancel_work);
-/* Will return if we need to evaluate cpu load again or not */
-static bool need_load_eval(struct cpu_common_dbs_info *shared,
- unsigned int sampling_rate)
+static void gov_cancel_work(struct cpufreq_policy *policy)
{
- if (policy_is_shared(shared->policy)) {
- ktime_t time_now = ktime_get();
- s64 delta_us = ktime_us_delta(time_now, shared->time_stamp);
-
- /* Do nothing if we recently have sampled */
- if (delta_us < (s64)(sampling_rate / 2))
- return false;
- else
- shared->time_stamp = time_now;
- }
+ struct policy_dbs_info *policy_dbs = policy->governor_data;
- return true;
+ gov_clear_update_util(policy_dbs->policy);
+ irq_work_sync(&policy_dbs->irq_work);
+ cancel_work_sync(&policy_dbs->work);
+ atomic_set(&policy_dbs->work_count, 0);
+ policy_dbs->work_in_progress = false;
}
static void dbs_work_handler(struct work_struct *work)
{
- struct cpu_common_dbs_info *shared = container_of(work, struct
- cpu_common_dbs_info, work);
+ struct policy_dbs_info *policy_dbs;
struct cpufreq_policy *policy;
- struct dbs_data *dbs_data;
- unsigned int sampling_rate, delay;
- bool eval_load;
-
- policy = shared->policy;
- dbs_data = policy->governor_data;
-
- /* Kill all timers */
- gov_cancel_timers(policy);
+ struct dbs_governor *gov;
- if (dbs_data->cdata->governor == GOV_CONSERVATIVE) {
- struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
+ policy_dbs = container_of(work, struct policy_dbs_info, work);
+ policy = policy_dbs->policy;
+ gov = dbs_governor_of(policy);
- sampling_rate = cs_tuners->sampling_rate;
- } else {
- struct od_dbs_tuners *od_tuners = dbs_data->tuners;
-
- sampling_rate = od_tuners->sampling_rate;
- }
-
- eval_load = need_load_eval(shared, sampling_rate);
+ /*
+ * Make sure cpufreq_governor_limits() isn't evaluating load or the
+ * ondemand governor isn't updating the sampling rate in parallel.
+ */
+ mutex_lock(&policy_dbs->timer_mutex);
+ gov_update_sample_delay(policy_dbs, gov->gov_dbs_timer(policy));
+ mutex_unlock(&policy_dbs->timer_mutex);
+ /* Allow the utilization update handler to queue up more work. */
+ atomic_set(&policy_dbs->work_count, 0);
/*
- * Make sure cpufreq_governor_limits() isn't evaluating load in
- * parallel.
+ * If the update below is reordered with respect to the sample delay
+ * modification, the utilization update handler may end up using a stale
+ * sample delay value.
*/
- mutex_lock(&shared->timer_mutex);
- delay = dbs_data->cdata->gov_dbs_timer(policy, eval_load);
- mutex_unlock(&shared->timer_mutex);
+ smp_wmb();
+ policy_dbs->work_in_progress = false;
+}
- atomic_dec(&shared->skip_work);
+static void dbs_irq_work(struct irq_work *irq_work)
+{
+ struct policy_dbs_info *policy_dbs;
- gov_add_timers(policy, delay);
+ policy_dbs = container_of(irq_work, struct policy_dbs_info, irq_work);
+ schedule_work_on(smp_processor_id(), &policy_dbs->work);
}
-static void dbs_timer_handler(unsigned long data)
+static void dbs_update_util_handler(struct update_util_data *data, u64 time,
+ unsigned long util, unsigned long max)
{
- struct cpu_dbs_info *cdbs = (struct cpu_dbs_info *)data;
- struct cpu_common_dbs_info *shared = cdbs->shared;
+ struct cpu_dbs_info *cdbs = container_of(data, struct cpu_dbs_info, update_util);
+ struct policy_dbs_info *policy_dbs = cdbs->policy_dbs;
+ u64 delta_ns, lst;
/*
- * Timer handler may not be allowed to queue the work at the moment,
- * because:
- * - Another timer handler has done that
- * - We are stopping the governor
- * - Or we are updating the sampling rate of the ondemand governor
+ * The work may not be allowed to be queued up right now.
+ * Possible reasons:
+ * - Work has already been queued up or is in progress.
+ * - It is too early (too little time from the previous sample).
*/
- if (atomic_inc_return(&shared->skip_work) > 1)
- atomic_dec(&shared->skip_work);
- else
- queue_work(system_wq, &shared->work);
-}
+ if (policy_dbs->work_in_progress)
+ return;
-static void set_sampling_rate(struct dbs_data *dbs_data,
- unsigned int sampling_rate)
-{
- if (dbs_data->cdata->governor == GOV_CONSERVATIVE) {
- struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
- cs_tuners->sampling_rate = sampling_rate;
- } else {
- struct od_dbs_tuners *od_tuners = dbs_data->tuners;
- od_tuners->sampling_rate = sampling_rate;
+ /*
+ * If the reads below are reordered before the check above, the value
+ * of sample_delay_ns used in the computation may be stale.
+ */
+ smp_rmb();
+ lst = READ_ONCE(policy_dbs->last_sample_time);
+ delta_ns = time - lst;
+ if ((s64)delta_ns < policy_dbs->sample_delay_ns)
+ return;
+
+ /*
+ * If the policy is not shared, the irq_work may be queued up right away
+ * at this point. Otherwise, we need to ensure that only one of the
+ * CPUs sharing the policy will do that.
+ */
+ if (policy_dbs->is_shared) {
+ if (!atomic_add_unless(&policy_dbs->work_count, 1, 1))
+ return;
+
+ /*
+ * If another CPU updated last_sample_time in the meantime, we
+ * shouldn't be here, so clear the work counter and bail out.
+ */
+ if (unlikely(lst != READ_ONCE(policy_dbs->last_sample_time))) {
+ atomic_set(&policy_dbs->work_count, 0);
+ return;
+ }
}
+
+ policy_dbs->last_sample_time = time;
+ policy_dbs->work_in_progress = true;
+ irq_work_queue(&policy_dbs->irq_work);
}
-static int alloc_common_dbs_info(struct cpufreq_policy *policy,
- struct common_dbs_data *cdata)
+static struct policy_dbs_info *alloc_policy_dbs_info(struct cpufreq_policy *policy,
+ struct dbs_governor *gov)
{
- struct cpu_common_dbs_info *shared;
+ struct policy_dbs_info *policy_dbs;
int j;
- /* Allocate memory for the common information for policy->cpus */
- shared = kzalloc(sizeof(*shared), GFP_KERNEL);
- if (!shared)
- return -ENOMEM;
+ /* Allocate memory for per-policy governor data. */
+ policy_dbs = gov->alloc();
+ if (!policy_dbs)
+ return NULL;
- /* Set shared for all CPUs, online+offline */
- for_each_cpu(j, policy->related_cpus)
- cdata->get_cpu_cdbs(j)->shared = shared;
+ policy_dbs->policy = policy;
+ mutex_init(&policy_dbs->timer_mutex);
+ atomic_set(&policy_dbs->work_count, 0);
+ init_irq_work(&policy_dbs->irq_work, dbs_irq_work);
+ INIT_WORK(&policy_dbs->work, dbs_work_handler);
- mutex_init(&shared->timer_mutex);
- atomic_set(&shared->skip_work, 0);
- INIT_WORK(&shared->work, dbs_work_handler);
- return 0;
+ /* Set policy_dbs for all CPUs, online+offline */
+ for_each_cpu(j, policy->related_cpus) {
+ struct cpu_dbs_info *j_cdbs = &per_cpu(cpu_dbs, j);
+
+ j_cdbs->policy_dbs = policy_dbs;
+ j_cdbs->update_util.func = dbs_update_util_handler;
+ }
+ return policy_dbs;
}
-static void free_common_dbs_info(struct cpufreq_policy *policy,
- struct common_dbs_data *cdata)
+static void free_policy_dbs_info(struct policy_dbs_info *policy_dbs,
+ struct dbs_governor *gov)
{
- struct cpu_dbs_info *cdbs = cdata->get_cpu_cdbs(policy->cpu);
- struct cpu_common_dbs_info *shared = cdbs->shared;
int j;
- mutex_destroy(&shared->timer_mutex);
+ mutex_destroy(&policy_dbs->timer_mutex);
- for_each_cpu(j, policy->cpus)
- cdata->get_cpu_cdbs(j)->shared = NULL;
+ for_each_cpu(j, policy_dbs->policy->related_cpus) {
+ struct cpu_dbs_info *j_cdbs = &per_cpu(cpu_dbs, j);
- kfree(shared);
+ j_cdbs->policy_dbs = NULL;
+ j_cdbs->update_util.func = NULL;
+ }
+ gov->free(policy_dbs);
}
-static int cpufreq_governor_init(struct cpufreq_policy *policy,
- struct dbs_data *dbs_data,
- struct common_dbs_data *cdata)
+static int cpufreq_governor_init(struct cpufreq_policy *policy)
{
+ struct dbs_governor *gov = dbs_governor_of(policy);
+ struct dbs_data *dbs_data;
+ struct policy_dbs_info *policy_dbs;
unsigned int latency;
- int ret;
+ int ret = 0;
/* State should be equivalent to EXIT */
if (policy->governor_data)
return -EBUSY;
- if (dbs_data) {
- if (WARN_ON(have_governor_per_policy()))
- return -EINVAL;
+ policy_dbs = alloc_policy_dbs_info(policy, gov);
+ if (!policy_dbs)
+ return -ENOMEM;
- ret = alloc_common_dbs_info(policy, cdata);
- if (ret)
- return ret;
+ /* Protect gov->gdbs_data against concurrent updates. */
+ mutex_lock(&gov_dbs_data_mutex);
+ dbs_data = gov->gdbs_data;
+ if (dbs_data) {
+ if (WARN_ON(have_governor_per_policy())) {
+ ret = -EINVAL;
+ goto free_policy_dbs_info;
+ }
+ policy_dbs->dbs_data = dbs_data;
+ policy->governor_data = policy_dbs;
+
+ mutex_lock(&dbs_data->mutex);
dbs_data->usage_count++;
- policy->governor_data = dbs_data;
- return 0;
+ list_add(&policy_dbs->list, &dbs_data->policy_dbs_list);
+ mutex_unlock(&dbs_data->mutex);
+ goto out;
}
dbs_data = kzalloc(sizeof(*dbs_data), GFP_KERNEL);
- if (!dbs_data)
- return -ENOMEM;
-
- ret = alloc_common_dbs_info(policy, cdata);
- if (ret)
- goto free_dbs_data;
+ if (!dbs_data) {
+ ret = -ENOMEM;
+ goto free_policy_dbs_info;
+ }
- dbs_data->cdata = cdata;
- dbs_data->usage_count = 1;
+ INIT_LIST_HEAD(&dbs_data->policy_dbs_list);
+ mutex_init(&dbs_data->mutex);
- ret = cdata->init(dbs_data, !policy->governor->initialized);
+ ret = gov->init(dbs_data, !policy->governor->initialized);
if (ret)
- goto free_common_dbs_info;
+ goto free_policy_dbs_info;
/* policy latency is in ns. Convert it to us first */
latency = policy->cpuinfo.transition_latency / 1000;
@@ -381,216 +477,156 @@ static int cpufreq_governor_init(struct cpufreq_policy *policy,
/* Bring kernel and HW constraints together */
dbs_data->min_sampling_rate = max(dbs_data->min_sampling_rate,
MIN_LATENCY_MULTIPLIER * latency);
- set_sampling_rate(dbs_data, max(dbs_data->min_sampling_rate,
- latency * LATENCY_MULTIPLIER));
+ dbs_data->sampling_rate = max(dbs_data->min_sampling_rate,
+ LATENCY_MULTIPLIER * latency);
if (!have_governor_per_policy())
- cdata->gdbs_data = dbs_data;
+ gov->gdbs_data = dbs_data;
- policy->governor_data = dbs_data;
+ policy->governor_data = policy_dbs;
- ret = sysfs_create_group(get_governor_parent_kobj(policy),
- get_sysfs_attr(dbs_data));
- if (ret)
- goto reset_gdbs_data;
+ policy_dbs->dbs_data = dbs_data;
+ dbs_data->usage_count = 1;
+ list_add(&policy_dbs->list, &dbs_data->policy_dbs_list);
- return 0;
+ gov->kobj_type.sysfs_ops = &governor_sysfs_ops;
+ ret = kobject_init_and_add(&dbs_data->kobj, &gov->kobj_type,
+ get_governor_parent_kobj(policy),
+ "%s", gov->gov.name);
+ if (!ret)
+ goto out;
+
+ /* Failure, so roll back. */
+ pr_err("cpufreq: Governor initialization failed (dbs_data kobject init error %d)\n", ret);
-reset_gdbs_data:
policy->governor_data = NULL;
if (!have_governor_per_policy())
- cdata->gdbs_data = NULL;
- cdata->exit(dbs_data, !policy->governor->initialized);
-free_common_dbs_info:
- free_common_dbs_info(policy, cdata);
-free_dbs_data:
+ gov->gdbs_data = NULL;
+ gov->exit(dbs_data, !policy->governor->initialized);
kfree(dbs_data);
+
+free_policy_dbs_info:
+ free_policy_dbs_info(policy_dbs, gov);
+
+out:
+ mutex_unlock(&gov_dbs_data_mutex);
return ret;
}
-static int cpufreq_governor_exit(struct cpufreq_policy *policy,
- struct dbs_data *dbs_data)
+static int cpufreq_governor_exit(struct cpufreq_policy *policy)
{
- struct common_dbs_data *cdata = dbs_data->cdata;
- struct cpu_dbs_info *cdbs = cdata->get_cpu_cdbs(policy->cpu);
+ struct dbs_governor *gov = dbs_governor_of(policy);
+ struct policy_dbs_info *policy_dbs = policy->governor_data;
+ struct dbs_data *dbs_data = policy_dbs->dbs_data;
+ int count;
- /* State should be equivalent to INIT */
- if (!cdbs->shared || cdbs->shared->policy)
- return -EBUSY;
+ /* Protect gov->gdbs_data against concurrent updates. */
+ mutex_lock(&gov_dbs_data_mutex);
+
+ mutex_lock(&dbs_data->mutex);
+ list_del(&policy_dbs->list);
+ count = --dbs_data->usage_count;
+ mutex_unlock(&dbs_data->mutex);
- if (!--dbs_data->usage_count) {
- sysfs_remove_group(get_governor_parent_kobj(policy),
- get_sysfs_attr(dbs_data));
+ if (!count) {
+ kobject_put(&dbs_data->kobj);
policy->governor_data = NULL;
if (!have_governor_per_policy())
- cdata->gdbs_data = NULL;
+ gov->gdbs_data = NULL;
- cdata->exit(dbs_data, policy->governor->initialized == 1);
+ gov->exit(dbs_data, policy->governor->initialized == 1);
+ mutex_destroy(&dbs_data->mutex);
kfree(dbs_data);
} else {
policy->governor_data = NULL;
}
- free_common_dbs_info(policy, cdata);
+ free_policy_dbs_info(policy_dbs, gov);
+
+ mutex_unlock(&gov_dbs_data_mutex);
return 0;
}
-static int cpufreq_governor_start(struct cpufreq_policy *policy,
- struct dbs_data *dbs_data)
+static int cpufreq_governor_start(struct cpufreq_policy *policy)
{
- struct common_dbs_data *cdata = dbs_data->cdata;
- unsigned int sampling_rate, ignore_nice, j, cpu = policy->cpu;
- struct cpu_dbs_info *cdbs = cdata->get_cpu_cdbs(cpu);
- struct cpu_common_dbs_info *shared = cdbs->shared;
- int io_busy = 0;
+ struct dbs_governor *gov = dbs_governor_of(policy);
+ struct policy_dbs_info *policy_dbs = policy->governor_data;
+ struct dbs_data *dbs_data = policy_dbs->dbs_data;
+ unsigned int sampling_rate, ignore_nice, j;
+ unsigned int io_busy;
if (!policy->cur)
return -EINVAL;
- /* State should be equivalent to INIT */
- if (!shared || shared->policy)
- return -EBUSY;
+ policy_dbs->is_shared = policy_is_shared(policy);
+ policy_dbs->rate_mult = 1;
- if (cdata->governor == GOV_CONSERVATIVE) {
- struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
-
- sampling_rate = cs_tuners->sampling_rate;
- ignore_nice = cs_tuners->ignore_nice_load;
- } else {
- struct od_dbs_tuners *od_tuners = dbs_data->tuners;
-
- sampling_rate = od_tuners->sampling_rate;
- ignore_nice = od_tuners->ignore_nice_load;
- io_busy = od_tuners->io_is_busy;
- }
-
- shared->policy = policy;
- shared->time_stamp = ktime_get();
+ sampling_rate = dbs_data->sampling_rate;
+ ignore_nice = dbs_data->ignore_nice_load;
+ io_busy = dbs_data->io_is_busy;
for_each_cpu(j, policy->cpus) {
- struct cpu_dbs_info *j_cdbs = cdata->get_cpu_cdbs(j);
+ struct cpu_dbs_info *j_cdbs = &per_cpu(cpu_dbs, j);
unsigned int prev_load;
- j_cdbs->prev_cpu_idle =
- get_cpu_idle_time(j, &j_cdbs->prev_cpu_wall, io_busy);
+ j_cdbs->prev_cpu_idle = get_cpu_idle_time(j, &j_cdbs->prev_cpu_wall, io_busy);
- prev_load = (unsigned int)(j_cdbs->prev_cpu_wall -
- j_cdbs->prev_cpu_idle);
- j_cdbs->prev_load = 100 * prev_load /
- (unsigned int)j_cdbs->prev_cpu_wall;
+ prev_load = j_cdbs->prev_cpu_wall - j_cdbs->prev_cpu_idle;
+ j_cdbs->prev_load = 100 * prev_load / (unsigned int)j_cdbs->prev_cpu_wall;
if (ignore_nice)
j_cdbs->prev_cpu_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE];
-
- __setup_timer(&j_cdbs->timer, dbs_timer_handler,
- (unsigned long)j_cdbs,
- TIMER_DEFERRABLE | TIMER_IRQSAFE);
}
- if (cdata->governor == GOV_CONSERVATIVE) {
- struct cs_cpu_dbs_info_s *cs_dbs_info =
- cdata->get_cpu_dbs_info_s(cpu);
-
- cs_dbs_info->down_skip = 0;
- cs_dbs_info->requested_freq = policy->cur;
- } else {
- struct od_ops *od_ops = cdata->gov_ops;
- struct od_cpu_dbs_info_s *od_dbs_info = cdata->get_cpu_dbs_info_s(cpu);
-
- od_dbs_info->rate_mult = 1;
- od_dbs_info->sample_type = OD_NORMAL_SAMPLE;
- od_ops->powersave_bias_init_cpu(cpu);
- }
+ gov->start(policy);
- gov_add_timers(policy, delay_for_sampling_rate(sampling_rate));
+ gov_set_update_util(policy_dbs, sampling_rate);
return 0;
}
-static int cpufreq_governor_stop(struct cpufreq_policy *policy,
- struct dbs_data *dbs_data)
+static int cpufreq_governor_stop(struct cpufreq_policy *policy)
{
- struct cpu_dbs_info *cdbs = dbs_data->cdata->get_cpu_cdbs(policy->cpu);
- struct cpu_common_dbs_info *shared = cdbs->shared;
-
- /* State should be equivalent to START */
- if (!shared || !shared->policy)
- return -EBUSY;
-
- gov_cancel_work(shared);
- shared->policy = NULL;
-
+ gov_cancel_work(policy);
return 0;
}
-static int cpufreq_governor_limits(struct cpufreq_policy *policy,
- struct dbs_data *dbs_data)
+static int cpufreq_governor_limits(struct cpufreq_policy *policy)
{
- struct common_dbs_data *cdata = dbs_data->cdata;
- unsigned int cpu = policy->cpu;
- struct cpu_dbs_info *cdbs = cdata->get_cpu_cdbs(cpu);
+ struct policy_dbs_info *policy_dbs = policy->governor_data;
- /* State should be equivalent to START */
- if (!cdbs->shared || !cdbs->shared->policy)
- return -EBUSY;
+ mutex_lock(&policy_dbs->timer_mutex);
+
+ if (policy->max < policy->cur)
+ __cpufreq_driver_target(policy, policy->max, CPUFREQ_RELATION_H);
+ else if (policy->min > policy->cur)
+ __cpufreq_driver_target(policy, policy->min, CPUFREQ_RELATION_L);
+
+ gov_update_sample_delay(policy_dbs, 0);
- mutex_lock(&cdbs->shared->timer_mutex);
- if (policy->max < cdbs->shared->policy->cur)
- __cpufreq_driver_target(cdbs->shared->policy, policy->max,
- CPUFREQ_RELATION_H);
- else if (policy->min > cdbs->shared->policy->cur)
- __cpufreq_driver_target(cdbs->shared->policy, policy->min,
- CPUFREQ_RELATION_L);
- dbs_check_cpu(dbs_data, cpu);
- mutex_unlock(&cdbs->shared->timer_mutex);
+ mutex_unlock(&policy_dbs->timer_mutex);
return 0;
}
-int cpufreq_governor_dbs(struct cpufreq_policy *policy,
- struct common_dbs_data *cdata, unsigned int event)
+int cpufreq_governor_dbs(struct cpufreq_policy *policy, unsigned int event)
{
- struct dbs_data *dbs_data;
- int ret;
-
- /* Lock governor to block concurrent initialization of governor */
- mutex_lock(&cdata->mutex);
-
- if (have_governor_per_policy())
- dbs_data = policy->governor_data;
- else
- dbs_data = cdata->gdbs_data;
-
- if (!dbs_data && (event != CPUFREQ_GOV_POLICY_INIT)) {
- ret = -EINVAL;
- goto unlock;
- }
-
- switch (event) {
- case CPUFREQ_GOV_POLICY_INIT:
- ret = cpufreq_governor_init(policy, dbs_data, cdata);
- break;
- case CPUFREQ_GOV_POLICY_EXIT:
- ret = cpufreq_governor_exit(policy, dbs_data);
- break;
- case CPUFREQ_GOV_START:
- ret = cpufreq_governor_start(policy, dbs_data);
- break;
- case CPUFREQ_GOV_STOP:
- ret = cpufreq_governor_stop(policy, dbs_data);
- break;
- case CPUFREQ_GOV_LIMITS:
- ret = cpufreq_governor_limits(policy, dbs_data);
- break;
- default:
- ret = -EINVAL;
+ if (event == CPUFREQ_GOV_POLICY_INIT) {
+ return cpufreq_governor_init(policy);
+ } else if (policy->governor_data) {
+ switch (event) {
+ case CPUFREQ_GOV_POLICY_EXIT:
+ return cpufreq_governor_exit(policy);
+ case CPUFREQ_GOV_START:
+ return cpufreq_governor_start(policy);
+ case CPUFREQ_GOV_STOP:
+ return cpufreq_governor_stop(policy);
+ case CPUFREQ_GOV_LIMITS:
+ return cpufreq_governor_limits(policy);
+ }
}
-
-unlock:
- mutex_unlock(&cdata->mutex);
-
- return ret;
+ return -EINVAL;
}
EXPORT_SYMBOL_GPL(cpufreq_governor_dbs);