diff options
| -rw-r--r-- | drivers/powercap/dtpm_cpu.c | 46 |
1 files changed, 39 insertions, 7 deletions
diff --git a/drivers/powercap/dtpm_cpu.c b/drivers/powercap/dtpm_cpu.c index 2e21e4e2b01f..44faa3a74db6 100644 --- a/drivers/powercap/dtpm_cpu.c +++ b/drivers/powercap/dtpm_cpu.c @@ -68,27 +68,59 @@ static u64 set_pd_power_limit(struct dtpm *dtpm, u64 power_limit) return power_limit; } +static u64 scale_pd_power_uw(struct cpumask *pd_mask, u64 power) +{ + unsigned long max = 0, sum_util = 0; + int cpu; + + for_each_cpu_and(cpu, pd_mask, cpu_online_mask) { + + /* + * The capacity is the same for all CPUs belonging to + * the same perf domain, so a single call to + * arch_scale_cpu_capacity() is enough. However, we + * need the CPU parameter to be initialized by the + * loop, so the call ends up in this block. + * + * We can initialize 'max' with a cpumask_first() call + * before the loop but the bits computation is not + * worth given the arch_scale_cpu_capacity() just + * returns a value where the resulting assembly code + * will be optimized by the compiler. + */ + max = arch_scale_cpu_capacity(cpu); + sum_util += sched_cpu_util(cpu, max); + } + + /* + * In the improbable case where all the CPUs of the perf + * domain are offline, 'max' will be zero and will lead to an + * illegal operation with a zero division. + */ + return max ? (power * ((sum_util << 10) / max)) >> 10 : 0; +} + static u64 get_pd_power_uw(struct dtpm *dtpm) { struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm); struct em_perf_domain *pd; - struct cpumask cpus; + struct cpumask *pd_mask; unsigned long freq; - int i, nr_cpus; + int i; pd = em_cpu_get(dtpm_cpu->cpu); - freq = cpufreq_quick_get(dtpm_cpu->cpu); - cpumask_and(&cpus, cpu_online_mask, to_cpumask(pd->cpus)); - nr_cpus = cpumask_weight(&cpus); + pd_mask = em_span_cpus(pd); + + freq = cpufreq_quick_get(dtpm_cpu->cpu); for (i = 0; i < pd->nr_perf_states; i++) { if (pd->table[i].frequency < freq) continue; - return pd->table[i].power * - MICROWATT_PER_MILLIWATT * nr_cpus; + return scale_pd_power_uw(pd_mask, pd->table[i].power * + MICROWATT_PER_MILLIWATT); } return 0; |