diff options
Diffstat (limited to 'include/linux/energy_model.h')
| -rw-r--r-- | include/linux/energy_model.h | 24 |
1 files changed, 20 insertions, 4 deletions
diff --git a/include/linux/energy_model.h b/include/linux/energy_model.h index 3f221dbf5f95..39dcadd492b5 100644 --- a/include/linux/energy_model.h +++ b/include/linux/energy_model.h @@ -11,7 +11,7 @@ #include <linux/types.h> /** - * em_perf_state - Performance state of a performance domain + * struct em_perf_state - Performance state of a performance domain * @frequency: The frequency in KHz, for consistency with CPUFreq * @power: The power consumed at this level (by 1 CPU or by a registered * device). It can be a total power: static and dynamic. @@ -25,7 +25,7 @@ struct em_perf_state { }; /** - * em_perf_domain - Performance domain + * struct em_perf_domain - Performance domain * @table: List of performance states, in ascending order * @nr_perf_states: Number of performance states * @milliwatts: Flag indicating the power values are in milli-Watts @@ -53,6 +53,22 @@ struct em_perf_domain { #ifdef CONFIG_ENERGY_MODEL #define EM_MAX_POWER 0xFFFF +/* + * Increase resolution of energy estimation calculations for 64-bit + * architectures. The extra resolution improves decision made by EAS for the + * task placement when two Performance Domains might provide similar energy + * estimation values (w/o better resolution the values could be equal). + * + * We increase resolution only if we have enough bits to allow this increased + * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit + * are pretty high and the returns do not justify the increased costs. + */ +#ifdef CONFIG_64BIT +#define em_scale_power(p) ((p) * 1000) +#else +#define em_scale_power(p) (p) +#endif + struct em_data_callback { /** * active_power() - Provide power at the next performance state of @@ -87,12 +103,12 @@ void em_dev_unregister_perf_domain(struct device *dev); /** * em_cpu_energy() - Estimates the energy consumed by the CPUs of a - performance domain + * performance domain * @pd : performance domain for which energy has to be estimated * @max_util : highest utilization among CPUs of the domain * @sum_util : sum of the utilization of all CPUs in the domain * @allowed_cpu_cap : maximum allowed CPU capacity for the @pd, which - might reflect reduced frequency (due to thermal) + * might reflect reduced frequency (due to thermal) * * This function must be used only for CPU devices. There is no validation, * i.e. if the EM is a CPU type and has cpumask allocated. It is called from |