diff options
Diffstat (limited to 'kernel/power/energy_model.c')
| -rw-r--r-- | kernel/power/energy_model.c | 137 |
1 files changed, 74 insertions, 63 deletions
diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c index 3874f0e97651..ea7995a25780 100644 --- a/kernel/power/energy_model.c +++ b/kernel/power/energy_model.c @@ -161,22 +161,10 @@ 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); + kfree_rcu(container_of(kref, struct em_perf_table, kref), rcu); } /** @@ -185,7 +173,7 @@ static void em_release_table_kref(struct kref *kref) * * No return values. */ -void em_table_free(struct em_perf_table __rcu *table) +void em_table_free(struct em_perf_table *table) { kref_put(&table->kref, em_release_table_kref); } @@ -198,9 +186,9 @@ void em_table_free(struct em_perf_table __rcu *table) * 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 *em_table_alloc(struct em_perf_domain *pd) { - struct em_perf_table __rcu *table; + struct em_perf_table *table; int table_size; table_size = sizeof(struct em_perf_state) * pd->nr_perf_states; @@ -239,12 +227,16 @@ static void em_init_performance(struct device *dev, struct em_perf_domain *pd, } static int em_compute_costs(struct device *dev, struct em_perf_state *table, - struct em_data_callback *cb, int nr_states, + const struct em_data_callback *cb, int nr_states, unsigned long flags) { unsigned long prev_cost = ULONG_MAX; int i, ret; + /* This is needed only for CPUs and EAS skip other devices */ + if (!_is_cpu_device(dev)) + return 0; + /* Compute the cost of each performance state. */ for (i = nr_states - 1; i >= 0; i--) { unsigned long power_res, cost; @@ -308,9 +300,9 @@ int em_dev_compute_costs(struct device *dev, struct em_perf_state *table, * 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 *new_table) { - struct em_perf_table __rcu *old_table; + struct em_perf_table *old_table; struct em_perf_domain *pd; if (!dev) @@ -327,7 +319,8 @@ int em_dev_update_perf_domain(struct device *dev, kref_get(&new_table->kref); - old_table = pd->em_table; + old_table = rcu_dereference_protected(pd->em_table, + lockdep_is_held(&em_pd_mutex)); rcu_assign_pointer(pd->em_table, new_table); em_cpufreq_update_efficiencies(dev, new_table->state); @@ -341,7 +334,7 @@ EXPORT_SYMBOL_GPL(em_dev_update_perf_domain); static int em_create_perf_table(struct device *dev, struct em_perf_domain *pd, struct em_perf_state *table, - struct em_data_callback *cb, + const struct em_data_callback *cb, unsigned long flags) { unsigned long power, freq, prev_freq = 0; @@ -396,10 +389,11 @@ static int em_create_perf_table(struct device *dev, struct em_perf_domain *pd, } static int em_create_pd(struct device *dev, int nr_states, - struct em_data_callback *cb, cpumask_t *cpus, + const struct em_data_callback *cb, + const cpumask_t *cpus, unsigned long flags) { - struct em_perf_table __rcu *em_table; + struct em_perf_table *em_table; struct em_perf_domain *pd; struct device *cpu_dev; int cpu, ret, num_cpus; @@ -556,9 +550,10 @@ EXPORT_SYMBOL_GPL(em_cpu_get); * Return 0 on success */ int em_dev_register_perf_domain(struct device *dev, unsigned int nr_states, - struct em_data_callback *cb, cpumask_t *cpus, - bool microwatts) + const struct em_data_callback *cb, + const cpumask_t *cpus, bool microwatts) { + struct em_perf_table *em_table; unsigned long cap, prev_cap = 0; unsigned long flags = 0; int cpu, ret; @@ -631,7 +626,9 @@ int em_dev_register_perf_domain(struct device *dev, unsigned int nr_states, dev->em_pd->min_perf_state = 0; dev->em_pd->max_perf_state = nr_states - 1; - em_cpufreq_update_efficiencies(dev, dev->em_pd->em_table->state); + em_table = rcu_dereference_protected(dev->em_pd->em_table, + lockdep_is_held(&em_pd_mutex)); + em_cpufreq_update_efficiencies(dev, em_table->state); em_debug_create_pd(dev); dev_info(dev, "EM: created perf domain\n"); @@ -668,7 +665,8 @@ void em_dev_unregister_perf_domain(struct device *dev) mutex_lock(&em_pd_mutex); em_debug_remove_pd(dev); - em_table_free(dev->em_pd->em_table); + em_table_free(rcu_dereference_protected(dev->em_pd->em_table, + lockdep_is_held(&em_pd_mutex))); kfree(dev->em_pd); dev->em_pd = NULL; @@ -676,9 +674,9 @@ void em_dev_unregister_perf_domain(struct device *dev) } EXPORT_SYMBOL_GPL(em_dev_unregister_perf_domain); -static struct em_perf_table __rcu *em_table_dup(struct em_perf_domain *pd) +static struct em_perf_table *em_table_dup(struct em_perf_domain *pd) { - struct em_perf_table __rcu *em_table; + struct em_perf_table *em_table; struct em_perf_state *ps, *new_ps; int ps_size; @@ -700,14 +698,16 @@ static struct em_perf_table __rcu *em_table_dup(struct em_perf_domain *pd) } static int em_recalc_and_update(struct device *dev, struct em_perf_domain *pd, - struct em_perf_table __rcu *em_table) + struct em_perf_table *em_table) { int ret; - ret = em_compute_costs(dev, em_table->state, NULL, pd->nr_perf_states, - pd->flags); - if (ret) - goto free_em_table; + if (!em_is_artificial(pd)) { + ret = em_compute_costs(dev, em_table->state, NULL, + pd->nr_perf_states, pd->flags); + if (ret) + goto free_em_table; + } ret = em_dev_update_perf_domain(dev, em_table); if (ret) @@ -727,11 +727,24 @@ free_em_table: * 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) +static void em_adjust_new_capacity(unsigned int cpu, struct device *dev, + struct em_perf_domain *pd) { - struct em_perf_table __rcu *em_table; + unsigned long cpu_capacity = arch_scale_cpu_capacity(cpu); + struct em_perf_table *em_table; + struct em_perf_state *table; + unsigned long em_max_perf; + + rcu_read_lock(); + table = em_perf_state_from_pd(pd); + em_max_perf = table[pd->nr_perf_states - 1].performance; + rcu_read_unlock(); + + if (em_max_perf == cpu_capacity) + return; + + pr_debug("updating cpu%d cpu_cap=%lu old capacity=%lu\n", cpu, + cpu_capacity, em_max_perf); em_table = em_table_dup(pd); if (!em_table) { @@ -744,12 +757,27 @@ static void em_adjust_new_capacity(struct device *dev, em_recalc_and_update(dev, pd, em_table); } +/** + * em_adjust_cpu_capacity() - Adjust the EM for a CPU after a capacity update. + * @cpu: Target CPU. + * + * Adjust the existing EM for @cpu after a capacity update under the assumption + * that the capacity has been updated in the same way for all of the CPUs in + * the same perf domain. + */ +void em_adjust_cpu_capacity(unsigned int cpu) +{ + struct device *dev = get_cpu_device(cpu); + struct em_perf_domain *pd; + + pd = em_pd_get(dev); + if (pd) + em_adjust_new_capacity(cpu, dev, pd); +} + 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)) { @@ -760,7 +788,7 @@ static void em_check_capacity_update(void) /* Check if CPUs capacity has changed than update EM */ for_each_possible_cpu(cpu) { struct cpufreq_policy *policy; - unsigned long em_max_perf; + struct em_perf_domain *pd; struct device *dev; if (cpumask_test_cpu(cpu, cpu_done_mask)) @@ -775,32 +803,15 @@ static void em_check_capacity_update(void) } cpufreq_cpu_put(policy); - pd = em_cpu_get(cpu); + dev = get_cpu_device(cpu); + pd = em_pd_get(dev); 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); + em_adjust_new_capacity(cpu, dev, pd); } free_cpumask_var(cpu_done_mask); @@ -822,7 +833,7 @@ static void em_update_workfn(struct work_struct *work) */ int em_dev_update_chip_binning(struct device *dev) { - struct em_perf_table __rcu *em_table; + struct em_perf_table *em_table; struct em_perf_domain *pd; int i, ret; |