From: Pierre Gondois <[email protected]>
The Energy Model (EM) can be used on platforms which are missing real
power information. Those platforms would implement .get_cost() which
populates needed values for the Energy Aware Scheduler (EAS). The EAS
doesn't use 'power' fields from EM, but other frameworks might use them.
Thus, to avoid miss-usage of this specific type of EM, introduce a new
flags which can be checked by other frameworks.
Signed-off-by: Pierre Gondois <[email protected]>
Signed-off-by: Lukasz Luba <[email protected]>
---
include/linux/energy_model.h | 5 +++++
kernel/power/energy_model.c | 2 ++
2 files changed, 7 insertions(+)
diff --git a/include/linux/energy_model.h b/include/linux/energy_model.h
index 0a3a5663177b..92e82a322859 100644
--- a/include/linux/energy_model.h
+++ b/include/linux/energy_model.h
@@ -67,11 +67,16 @@ struct em_perf_domain {
*
* EM_PERF_DOMAIN_SKIP_INEFFICIENCIES: Skip inefficient states when estimating
* energy consumption.
+ *
+ * EM_PERF_DOMAIN_ARTIFICIAL: The power values are artificial and might be
+ * created by platform missing real power information
*/
#define EM_PERF_DOMAIN_MILLIWATTS BIT(0)
#define EM_PERF_DOMAIN_SKIP_INEFFICIENCIES BIT(1)
+#define EM_PERF_DOMAIN_ARTIFICIAL BIT(2)
#define em_span_cpus(em) (to_cpumask((em)->cpus))
+#define em_is_artificial(em) ((em)->flags & EM_PERF_DOMAIN_ARTIFICIAL)
#ifdef CONFIG_ENERGY_MODEL
#define EM_MAX_POWER 0xFFFF
diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c
index 0153b0ca7b23..6ecee99af842 100644
--- a/kernel/power/energy_model.c
+++ b/kernel/power/energy_model.c
@@ -384,6 +384,8 @@ int em_dev_register_perf_domain(struct device *dev, unsigned int nr_states,
if (milliwatts)
dev->em_pd->flags |= EM_PERF_DOMAIN_MILLIWATTS;
+ else if (cb->get_cost)
+ dev->em_pd->flags |= EM_PERF_DOMAIN_ARTIFICIAL;
em_cpufreq_update_efficiencies(dev);
--
2.17.1
On Monday 21 Mar 2022 at 09:57:23 (+0000), Lukasz Luba wrote:
> From: Pierre Gondois <[email protected]>
>
> The Energy Model (EM) can be used on platforms which are missing real
> power information. Those platforms would implement .get_cost() which
> populates needed values for the Energy Aware Scheduler (EAS). The EAS
> doesn't use 'power' fields from EM, but other frameworks might use them.
> Thus, to avoid miss-usage of this specific type of EM, introduce a new
> flags which can be checked by other frameworks.
>
> Signed-off-by: Pierre Gondois <[email protected]>
> Signed-off-by: Lukasz Luba <[email protected]>
> ---
> include/linux/energy_model.h | 5 +++++
> kernel/power/energy_model.c | 2 ++
> 2 files changed, 7 insertions(+)
>
> diff --git a/include/linux/energy_model.h b/include/linux/energy_model.h
> index 0a3a5663177b..92e82a322859 100644
> --- a/include/linux/energy_model.h
> +++ b/include/linux/energy_model.h
> @@ -67,11 +67,16 @@ struct em_perf_domain {
> *
> * EM_PERF_DOMAIN_SKIP_INEFFICIENCIES: Skip inefficient states when estimating
> * energy consumption.
> + *
> + * EM_PERF_DOMAIN_ARTIFICIAL: The power values are artificial and might be
> + * created by platform missing real power information
> */
> #define EM_PERF_DOMAIN_MILLIWATTS BIT(0)
> #define EM_PERF_DOMAIN_SKIP_INEFFICIENCIES BIT(1)
> +#define EM_PERF_DOMAIN_ARTIFICIAL BIT(2)
>
> #define em_span_cpus(em) (to_cpumask((em)->cpus))
> +#define em_is_artificial(em) ((em)->flags & EM_PERF_DOMAIN_ARTIFICIAL)
>
> #ifdef CONFIG_ENERGY_MODEL
> #define EM_MAX_POWER 0xFFFF
> diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c
> index 0153b0ca7b23..6ecee99af842 100644
> --- a/kernel/power/energy_model.c
> +++ b/kernel/power/energy_model.c
> @@ -384,6 +384,8 @@ int em_dev_register_perf_domain(struct device *dev, unsigned int nr_states,
>
> if (milliwatts)
> dev->em_pd->flags |= EM_PERF_DOMAIN_MILLIWATTS;
> + else if (cb->get_cost)
> + dev->em_pd->flags |= EM_PERF_DOMAIN_ARTIFICIAL;
>
> em_cpufreq_update_efficiencies(dev);
>
Reviewed-by: Ionela Voinescu <[email protected]>
> --
> 2.17.1
>