diff options
Diffstat (limited to 'kernel/power')
| -rw-r--r-- | kernel/power/energy_model.c | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c index 41418aa6daa6..b192b0ac8c6e 100644 --- a/kernel/power/energy_model.c +++ b/kernel/power/energy_model.c @@ -25,6 +25,9 @@ static DEFINE_MUTEX(em_pd_mutex); static void em_cpufreq_update_efficiencies(struct device *dev, struct em_perf_state *table); +static void em_check_capacity_update(void); +static void em_update_workfn(struct work_struct *work); +static DECLARE_DELAYED_WORK(em_update_work, em_update_workfn); static bool _is_cpu_device(struct device *dev) { @@ -583,6 +586,10 @@ int em_dev_register_perf_domain(struct device *dev, unsigned int nr_states, unlock: mutex_unlock(&em_pd_mutex); + + if (_is_cpu_device(dev)) + em_check_capacity_update(); + return ret; } EXPORT_SYMBOL_GPL(em_dev_register_perf_domain); @@ -618,3 +625,120 @@ void em_dev_unregister_perf_domain(struct device *dev) mutex_unlock(&em_pd_mutex); } EXPORT_SYMBOL_GPL(em_dev_unregister_perf_domain); + +/* + * Adjustment of CPU performance values after boot, when all CPUs capacites + * are correctly calculated. + */ +static void em_adjust_new_capacity(struct device *dev, + struct em_perf_domain *pd, + u64 max_cap) +{ + struct em_perf_table __rcu *em_table; + struct em_perf_state *ps, *new_ps; + int ret, ps_size; + + em_table = em_table_alloc(pd); + if (!em_table) { + dev_warn(dev, "EM: allocation failed\n"); + return; + } + + new_ps = em_table->state; + + rcu_read_lock(); + ps = em_perf_state_from_pd(pd); + /* Initialize data based on old table */ + ps_size = sizeof(struct em_perf_state) * pd->nr_perf_states; + memcpy(new_ps, ps, ps_size); + + rcu_read_unlock(); + + em_init_performance(dev, pd, new_ps, pd->nr_perf_states); + ret = em_compute_costs(dev, new_ps, NULL, pd->nr_perf_states, + pd->flags); + if (ret) { + dev_warn(dev, "EM: compute costs failed\n"); + return; + } + + ret = em_dev_update_perf_domain(dev, em_table); + if (ret) + dev_warn(dev, "EM: update failed %d\n", ret); + + /* + * This is one-time-update, so give up the ownership in this updater. + * The EM framework has incremented the usage counter and from now + * will keep the reference (then free the memory when needed). + */ + em_table_free(em_table); +} + +static void em_check_capacity_update(void) +{ + cpumask_var_t cpu_done_mask; + struct em_perf_state *table; + struct em_perf_domain *pd; + unsigned long cpu_capacity; + int cpu; + + if (!zalloc_cpumask_var(&cpu_done_mask, GFP_KERNEL)) { + pr_warn("no free memory\n"); + return; + } + + /* Check if CPUs capacity has changed than update EM */ + for_each_possible_cpu(cpu) { + struct cpufreq_policy *policy; + unsigned long em_max_perf; + struct device *dev; + int nr_states; + + if (cpumask_test_cpu(cpu, cpu_done_mask)) + continue; + + policy = cpufreq_cpu_get(cpu); + if (!policy) { + pr_debug("Accessing cpu%d policy failed\n", cpu); + schedule_delayed_work(&em_update_work, + msecs_to_jiffies(1000)); + break; + } + cpufreq_cpu_put(policy); + + pd = em_cpu_get(cpu); + if (!pd || em_is_artificial(pd)) + continue; + + cpumask_or(cpu_done_mask, cpu_done_mask, + em_span_cpus(pd)); + + nr_states = pd->nr_perf_states; + cpu_capacity = arch_scale_cpu_capacity(cpu); + + rcu_read_lock(); + table = em_perf_state_from_pd(pd); + em_max_perf = table[pd->nr_perf_states - 1].performance; + rcu_read_unlock(); + + /* + * Check if the CPU capacity has been adjusted during boot + * and trigger the update for new performance values. + */ + if (em_max_perf == cpu_capacity) + continue; + + pr_debug("updating cpu%d cpu_cap=%lu old capacity=%lu\n", + cpu, cpu_capacity, em_max_perf); + + dev = get_cpu_device(cpu); + em_adjust_new_capacity(dev, pd, cpu_capacity); + } + + free_cpumask_var(cpu_done_mask); +} + +static void em_update_workfn(struct work_struct *work) +{ + em_check_capacity_update(); +} |