diff options
-rw-r--r-- | include/linux/energy_model.h | 12 | ||||
-rw-r--r-- | kernel/power/energy_model.c | 53 |
2 files changed, 65 insertions, 0 deletions
diff --git a/include/linux/energy_model.h b/include/linux/energy_model.h index 1dcd1645dde7..8ddf1d8a9581 100644 --- a/include/linux/energy_model.h +++ b/include/linux/energy_model.h @@ -37,8 +37,19 @@ struct em_perf_state { #define EM_PERF_STATE_INEFFICIENT BIT(0) /** + * struct em_perf_table - Performance states table + * @rcu: RCU used for safe access and destruction + * @state: List of performance states, in ascending order + */ +struct em_perf_table { + struct rcu_head rcu; + struct em_perf_state state[]; +}; + +/** * struct em_perf_domain - Performance domain * @table: List of performance states, in ascending order + * @em_table: Pointer to the runtime modifiable em_perf_table * @nr_perf_states: Number of performance states * @flags: See "em_perf_domain flags" * @cpus: Cpumask covering the CPUs of the domain. It's here @@ -54,6 +65,7 @@ struct em_perf_state { */ struct em_perf_domain { struct em_perf_state *table; + struct em_perf_table __rcu *em_table; int nr_perf_states; unsigned long flags; unsigned long cpus[]; diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c index 7468fa92134b..131ff1d0dc5b 100644 --- a/kernel/power/energy_model.c +++ b/kernel/power/energy_model.c @@ -23,6 +23,9 @@ */ static DEFINE_MUTEX(em_pd_mutex); +static void em_cpufreq_update_efficiencies(struct device *dev, + struct em_perf_state *table); + static bool _is_cpu_device(struct device *dev) { return (dev->bus == &cpu_subsys); @@ -103,6 +106,31 @@ 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_free_table(struct em_perf_table __rcu *table) +{ + call_rcu(&table->rcu, em_destroy_table_rcu); +} + +static struct em_perf_table __rcu * +em_allocate_table(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); + return table; +} + static int em_compute_costs(struct device *dev, struct em_perf_state *table, struct em_data_callback *cb, int nr_states, unsigned long flags) @@ -153,6 +181,24 @@ static int em_allocate_perf_table(struct em_perf_domain *pd, return 0; } +static int em_create_runtime_table(struct em_perf_domain *pd) +{ + struct em_perf_table __rcu *table; + int table_size; + + table = em_allocate_table(pd); + if (!table) + return -ENOMEM; + + /* Initialize runtime table with existing data */ + table_size = sizeof(struct em_perf_state) * pd->nr_perf_states; + memcpy(table->state, pd->table, table_size); + + rcu_assign_pointer(pd->em_table, table); + + return 0; +} + static int em_create_perf_table(struct device *dev, struct em_perf_domain *pd, struct em_perf_state *table, struct em_data_callback *cb, @@ -245,6 +291,10 @@ static int em_create_pd(struct device *dev, int nr_states, if (ret) goto free_pd_table; + ret = em_create_runtime_table(pd); + if (ret) + goto free_pd_table; + if (_is_cpu_device(dev)) for_each_cpu(cpu, cpus) { cpu_dev = get_cpu_device(cpu); @@ -461,6 +511,9 @@ void em_dev_unregister_perf_domain(struct device *dev) em_debug_remove_pd(dev); kfree(dev->em_pd->table); + + em_free_table(dev->em_pd->em_table); + kfree(dev->em_pd); dev->em_pd = NULL; mutex_unlock(&em_pd_mutex); |