diff options
Diffstat (limited to 'drivers/cpufreq/cpufreq_governor.c')
| -rw-r--r-- | drivers/cpufreq/cpufreq_governor.c | 766 |
1 files changed, 403 insertions, 363 deletions
diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c index e0d111024d48..1c25ef405616 100644 --- a/drivers/cpufreq/cpufreq_governor.c +++ b/drivers/cpufreq/cpufreq_governor.c @@ -18,95 +18,193 @@ #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); - j_cdbs->prev_cpu_idle = cur_idle_time; + if (cur_idle_time <= j_cdbs->prev_cpu_idle) { + idle_time = 0; + } else { + 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 +226,10 @@ 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 +254,224 @@ 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; + struct dbs_governor *gov; - /* Kill all timers */ - gov_cancel_timers(policy); + policy_dbs = container_of(work, struct policy_dbs_info, work); + policy = policy_dbs->policy; + gov = dbs_governor_of(policy); - if (dbs_data->cdata->governor == GOV_CONSERVATIVE) { - struct cs_dbs_tuners *cs_tuners = dbs_data->tuners; - - 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(&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 +481,156 @@ 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); |