diff options
Diffstat (limited to 'kernel/power')
| -rw-r--r-- | kernel/power/energy_model.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c index 16795743f969..667619b70be7 100644 --- a/kernel/power/energy_model.c +++ b/kernel/power/energy_model.c @@ -209,6 +209,50 @@ static int em_allocate_perf_table(struct em_perf_domain *pd, return 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_runtime_table(struct em_perf_domain *pd) { struct em_perf_table __rcu *table; |