From 8b0a8165cdad0f4133837d753649ef4682e42c3b Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 7 Aug 2024 15:11:40 +0200 Subject: Merging upstream version 6.9.7. Signed-off-by: Daniel Baumann --- kernel/power/energy_model.c | 484 ++++++++++++++++++++++++++++++++++++++------ 1 file changed, 418 insertions(+), 66 deletions(-) (limited to 'kernel/power/energy_model.c') diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c index 7b44f5b89f..9e1c9aa399 100644 --- a/kernel/power/energy_model.c +++ b/kernel/power/energy_model.c @@ -23,6 +23,12 @@ */ 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) { return (dev->bus == &cpu_subsys); @@ -31,19 +37,65 @@ static bool _is_cpu_device(struct device *dev) #ifdef CONFIG_DEBUG_FS static struct dentry *rootdir; -static void em_debug_create_ps(struct em_perf_state *ps, struct dentry *pd) +struct em_dbg_info { + struct em_perf_domain *pd; + int ps_id; +}; + +#define DEFINE_EM_DBG_SHOW(name, fname) \ +static int em_debug_##fname##_show(struct seq_file *s, void *unused) \ +{ \ + struct em_dbg_info *em_dbg = s->private; \ + struct em_perf_state *table; \ + unsigned long val; \ + \ + rcu_read_lock(); \ + table = em_perf_state_from_pd(em_dbg->pd); \ + val = table[em_dbg->ps_id].name; \ + rcu_read_unlock(); \ + \ + seq_printf(s, "%lu\n", val); \ + return 0; \ +} \ +DEFINE_SHOW_ATTRIBUTE(em_debug_##fname) + +DEFINE_EM_DBG_SHOW(frequency, frequency); +DEFINE_EM_DBG_SHOW(power, power); +DEFINE_EM_DBG_SHOW(cost, cost); +DEFINE_EM_DBG_SHOW(performance, performance); +DEFINE_EM_DBG_SHOW(flags, inefficiency); + +static void em_debug_create_ps(struct em_perf_domain *em_pd, + struct em_dbg_info *em_dbg, int i, + struct dentry *pd) { + struct em_perf_state *table; + unsigned long freq; struct dentry *d; char name[24]; - snprintf(name, sizeof(name), "ps:%lu", ps->frequency); + em_dbg[i].pd = em_pd; + em_dbg[i].ps_id = i; + + rcu_read_lock(); + table = em_perf_state_from_pd(em_pd); + freq = table[i].frequency; + rcu_read_unlock(); + + snprintf(name, sizeof(name), "ps:%lu", freq); /* Create per-ps directory */ d = debugfs_create_dir(name, pd); - debugfs_create_ulong("frequency", 0444, d, &ps->frequency); - debugfs_create_ulong("power", 0444, d, &ps->power); - debugfs_create_ulong("cost", 0444, d, &ps->cost); - debugfs_create_ulong("inefficient", 0444, d, &ps->flags); + debugfs_create_file("frequency", 0444, d, &em_dbg[i], + &em_debug_frequency_fops); + debugfs_create_file("power", 0444, d, &em_dbg[i], + &em_debug_power_fops); + debugfs_create_file("cost", 0444, d, &em_dbg[i], + &em_debug_cost_fops); + debugfs_create_file("performance", 0444, d, &em_dbg[i], + &em_debug_performance_fops); + debugfs_create_file("inefficient", 0444, d, &em_dbg[i], + &em_debug_inefficiency_fops); } static int em_debug_cpus_show(struct seq_file *s, void *unused) @@ -66,6 +118,7 @@ DEFINE_SHOW_ATTRIBUTE(em_debug_flags); static void em_debug_create_pd(struct device *dev) { + struct em_dbg_info *em_dbg; struct dentry *d; int i; @@ -79,9 +132,14 @@ static void em_debug_create_pd(struct device *dev) debugfs_create_file("flags", 0444, d, dev->em_pd, &em_debug_flags_fops); + em_dbg = devm_kcalloc(dev, dev->em_pd->nr_perf_states, + sizeof(*em_dbg), GFP_KERNEL); + if (!em_dbg) + return; + /* Create a sub-directory for each performance state */ for (i = 0; i < dev->em_pd->nr_perf_states; i++) - em_debug_create_ps(&dev->em_pd->table[i], d); + em_debug_create_ps(dev->em_pd, em_dbg, i, d); } @@ -103,18 +161,192 @@ static void em_debug_create_pd(struct device *dev) {} static void em_debug_remove_pd(struct device *dev) {} #endif +static void em_destroy_table_rcu(struct rcu_head *rp) +{ + struct em_perf_table __rcu *table; + + table = container_of(rp, struct em_perf_table, rcu); + kfree(table); +} + +static void em_release_table_kref(struct kref *kref) +{ + struct em_perf_table __rcu *table; + + /* It was the last owner of this table so we can free */ + table = container_of(kref, struct em_perf_table, kref); + + call_rcu(&table->rcu, em_destroy_table_rcu); +} + +/** + * em_table_free() - Handles safe free of the EM table when needed + * @table : EM table which is going to be freed + * + * No return values. + */ +void em_table_free(struct em_perf_table __rcu *table) +{ + kref_put(&table->kref, em_release_table_kref); +} + +/** + * em_table_alloc() - Allocate a new EM table + * @pd : EM performance domain for which this must be done + * + * Allocate a new EM table and initialize its kref to indicate that it + * has a user. + * Returns allocated table or NULL. + */ +struct em_perf_table __rcu *em_table_alloc(struct em_perf_domain *pd) +{ + struct em_perf_table __rcu *table; + int table_size; + + table_size = sizeof(struct em_perf_state) * pd->nr_perf_states; + + table = kzalloc(sizeof(*table) + table_size, GFP_KERNEL); + if (!table) + return NULL; + + kref_init(&table->kref); + + return table; +} + +static void em_init_performance(struct device *dev, struct em_perf_domain *pd, + struct em_perf_state *table, int nr_states) +{ + u64 fmax, max_cap; + int i, cpu; + + /* This is needed only for CPUs and EAS skip other devices */ + if (!_is_cpu_device(dev)) + return; + + cpu = cpumask_first(em_span_cpus(pd)); + + /* + * Calculate the performance value for each frequency with + * linear relationship. The final CPU capacity might not be ready at + * boot time, but the EM will be updated a bit later with correct one. + */ + fmax = (u64) table[nr_states - 1].frequency; + max_cap = (u64) arch_scale_cpu_capacity(cpu); + for (i = 0; i < nr_states; i++) + table[i].performance = div64_u64(max_cap * table[i].frequency, + fmax); +} + +static int em_compute_costs(struct device *dev, struct em_perf_state *table, + struct em_data_callback *cb, int nr_states, + unsigned long flags) +{ + unsigned long prev_cost = ULONG_MAX; + int i, ret; + + /* Compute the cost of each performance state. */ + for (i = nr_states - 1; i >= 0; i--) { + unsigned long power_res, cost; + + if ((flags & EM_PERF_DOMAIN_ARTIFICIAL) && cb->get_cost) { + ret = cb->get_cost(dev, table[i].frequency, &cost); + if (ret || !cost || cost > EM_MAX_POWER) { + dev_err(dev, "EM: invalid cost %lu %d\n", + cost, ret); + return -EINVAL; + } + } else { + /* increase resolution of 'cost' precision */ + power_res = table[i].power * 10; + cost = power_res / table[i].performance; + } + + table[i].cost = cost; + + if (table[i].cost >= prev_cost) { + table[i].flags = EM_PERF_STATE_INEFFICIENT; + dev_dbg(dev, "EM: OPP:%lu is inefficient\n", + table[i].frequency); + } else { + prev_cost = table[i].cost; + } + } + + return 0; +} + +/** + * em_dev_compute_costs() - Calculate cost values for new runtime EM table + * @dev : Device for which the EM table is to be updated + * @table : The new EM table that is going to get the costs calculated + * @nr_states : Number of performance states + * + * Calculate the em_perf_state::cost values for new runtime EM table. The + * values are used for EAS during task placement. It also calculates and sets + * the efficiency flag for each performance state. When the function finish + * successfully the EM table is ready to be updated and used by EAS. + * + * Return 0 on success or a proper error in case of failure. + */ +int em_dev_compute_costs(struct device *dev, struct em_perf_state *table, + int nr_states) +{ + return em_compute_costs(dev, table, NULL, nr_states, 0); +} + +/** + * em_dev_update_perf_domain() - Update runtime EM table for a device + * @dev : Device for which the EM is to be updated + * @new_table : The new EM table that is going to be used from now + * + * Update EM runtime modifiable table for the @dev using the provided @table. + * + * This function uses a mutex to serialize writers, so it must not be called + * from a non-sleeping context. + * + * Return 0 on success or an error code on failure. + */ +int em_dev_update_perf_domain(struct device *dev, + struct em_perf_table __rcu *new_table) +{ + struct em_perf_table __rcu *old_table; + struct em_perf_domain *pd; + + if (!dev) + return -EINVAL; + + /* Serialize update/unregister or concurrent updates */ + mutex_lock(&em_pd_mutex); + + if (!dev->em_pd) { + mutex_unlock(&em_pd_mutex); + return -EINVAL; + } + pd = dev->em_pd; + + kref_get(&new_table->kref); + + old_table = pd->em_table; + rcu_assign_pointer(pd->em_table, new_table); + + em_cpufreq_update_efficiencies(dev, new_table->state); + + em_table_free(old_table); + + mutex_unlock(&em_pd_mutex); + return 0; +} +EXPORT_SYMBOL_GPL(em_dev_update_perf_domain); + static int em_create_perf_table(struct device *dev, struct em_perf_domain *pd, - int nr_states, struct em_data_callback *cb, + struct em_perf_state *table, + struct em_data_callback *cb, unsigned long flags) { - unsigned long power, freq, prev_freq = 0, prev_cost = ULONG_MAX; - struct em_perf_state *table; + unsigned long power, freq, prev_freq = 0; + int nr_states = pd->nr_perf_states; int i, ret; - u64 fmax; - - table = kcalloc(nr_states, sizeof(*table), GFP_KERNEL); - if (!table) - return -ENOMEM; /* Build the list of performance states for this performance domain */ for (i = 0, freq = 0; i < nr_states; i++, freq++) { @@ -127,7 +359,7 @@ static int em_create_perf_table(struct device *dev, struct em_perf_domain *pd, if (ret) { dev_err(dev, "EM: invalid perf. state: %d\n", ret); - goto free_ps_table; + return -EINVAL; } /* @@ -137,7 +369,7 @@ static int em_create_perf_table(struct device *dev, struct em_perf_domain *pd, if (freq <= prev_freq) { dev_err(dev, "EM: non-increasing freq: %lu\n", freq); - goto free_ps_table; + return -EINVAL; } /* @@ -147,55 +379,27 @@ static int em_create_perf_table(struct device *dev, struct em_perf_domain *pd, if (!power || power > EM_MAX_POWER) { dev_err(dev, "EM: invalid power: %lu\n", power); - goto free_ps_table; + return -EINVAL; } table[i].power = power; table[i].frequency = prev_freq = freq; } - /* Compute the cost of each performance state. */ - fmax = (u64) table[nr_states - 1].frequency; - for (i = nr_states - 1; i >= 0; i--) { - unsigned long power_res, cost; - - if (flags & EM_PERF_DOMAIN_ARTIFICIAL) { - ret = cb->get_cost(dev, table[i].frequency, &cost); - if (ret || !cost || cost > EM_MAX_POWER) { - dev_err(dev, "EM: invalid cost %lu %d\n", - cost, ret); - goto free_ps_table; - } - } else { - power_res = table[i].power; - cost = div64_u64(fmax * power_res, table[i].frequency); - } - - table[i].cost = cost; - - if (table[i].cost >= prev_cost) { - table[i].flags = EM_PERF_STATE_INEFFICIENT; - dev_dbg(dev, "EM: OPP:%lu is inefficient\n", - table[i].frequency); - } else { - prev_cost = table[i].cost; - } - } + em_init_performance(dev, pd, table, nr_states); - pd->table = table; - pd->nr_perf_states = nr_states; + ret = em_compute_costs(dev, table, cb, nr_states, flags); + if (ret) + return -EINVAL; return 0; - -free_ps_table: - kfree(table); - return -EINVAL; } static int em_create_pd(struct device *dev, int nr_states, struct em_data_callback *cb, cpumask_t *cpus, unsigned long flags) { + struct em_perf_table __rcu *em_table; struct em_perf_domain *pd; struct device *cpu_dev; int cpu, ret, num_cpus; @@ -220,11 +424,17 @@ static int em_create_pd(struct device *dev, int nr_states, return -ENOMEM; } - ret = em_create_perf_table(dev, pd, nr_states, cb, flags); - if (ret) { - kfree(pd); - return ret; - } + pd->nr_perf_states = nr_states; + + em_table = em_table_alloc(pd); + if (!em_table) + goto free_pd; + + ret = em_create_perf_table(dev, pd, em_table->state, cb, flags); + if (ret) + goto free_pd_table; + + rcu_assign_pointer(pd->em_table, em_table); if (_is_cpu_device(dev)) for_each_cpu(cpu, cpus) { @@ -235,26 +445,37 @@ static int em_create_pd(struct device *dev, int nr_states, dev->em_pd = pd; return 0; + +free_pd_table: + kfree(em_table); +free_pd: + kfree(pd); + return -EINVAL; } -static void em_cpufreq_update_efficiencies(struct device *dev) +static void +em_cpufreq_update_efficiencies(struct device *dev, struct em_perf_state *table) { struct em_perf_domain *pd = dev->em_pd; - struct em_perf_state *table; struct cpufreq_policy *policy; int found = 0; - int i; + int i, cpu; - if (!_is_cpu_device(dev) || !pd) + if (!_is_cpu_device(dev)) return; - policy = cpufreq_cpu_get(cpumask_first(em_span_cpus(pd))); - if (!policy) { - dev_warn(dev, "EM: Access to CPUFreq policy failed"); + /* Try to get a CPU which is active and in this PD */ + cpu = cpumask_first_and(em_span_cpus(pd), cpu_active_mask); + if (cpu >= nr_cpu_ids) { + dev_warn(dev, "EM: No online CPU for CPUFreq policy\n"); return; } - table = pd->table; + policy = cpufreq_cpu_get(cpu); + if (!policy) { + dev_warn(dev, "EM: Access to CPUFreq policy failed\n"); + return; + } for (i = 0; i < pd->nr_perf_states; i++) { if (!(table[i].flags & EM_PERF_STATE_INEFFICIENT)) @@ -391,19 +612,34 @@ int em_dev_register_perf_domain(struct device *dev, unsigned int nr_states, else if (cb->get_cost) flags |= EM_PERF_DOMAIN_ARTIFICIAL; + /* + * EM only supports uW (exception is artificial EM). + * Therefore, check and force the drivers to provide + * power in uW. + */ + if (!microwatts && !(flags & EM_PERF_DOMAIN_ARTIFICIAL)) { + dev_err(dev, "EM: only supports uW power values\n"); + ret = -EINVAL; + goto unlock; + } + ret = em_create_pd(dev, nr_states, cb, cpus, flags); if (ret) goto unlock; dev->em_pd->flags |= flags; - em_cpufreq_update_efficiencies(dev); + em_cpufreq_update_efficiencies(dev, dev->em_pd->em_table->state); em_debug_create_pd(dev); dev_info(dev, "EM: created perf domain\n"); 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); @@ -430,9 +666,125 @@ void em_dev_unregister_perf_domain(struct device *dev) mutex_lock(&em_pd_mutex); em_debug_remove_pd(dev); - kfree(dev->em_pd->table); + em_table_free(dev->em_pd->em_table); + kfree(dev->em_pd); dev->em_pd = NULL; 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; + + 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)); + + 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(); +} -- cgit v1.2.3