Re: [PATCH v8 11/16] sched/fair: uclamp: Add uclamp support to energy_compute()
From: Peter Zijlstra <peterz@infradead.org>
Date: 2019-05-09 12:51:16
Also in:
linux-pm, lkml
On Tue, Apr 02, 2019 at 11:41:47AM +0100, Patrick Bellasi wrote:
quoted hunk ↗ jump to hunk
@@ -6484,11 +6494,29 @@ compute_energy(struct task_struct *p, int dst_cpu, struct perf_domain *pd) * it will not appear in its pd list and will not be accounted * by compute_energy(). */ - for_each_cpu_and(cpu, perf_domain_span(pd), cpu_online_mask) { - util = cpu_util_next(cpu, p, dst_cpu); - util = schedutil_energy_util(cpu, util); - max_util = max(util, max_util); - sum_util += util; + for_each_cpu_and(cpu, pd_mask, cpu_online_mask) { + util_cfs = cpu_util_next(cpu, p, dst_cpu); + + /* + * Busy time computation: utilization clamping is not + * required since the ratio (sum_util / cpu_capacity) + * is already enough to scale the EM reported power + * consumption at the (eventually clamped) cpu_capacity. + */ + sum_util += schedutil_cpu_util(cpu, util_cfs, cpu_cap, + ENERGY_UTIL, NULL); + + /* + * Performance domain frequency: utilization clamping + * must be considered since it affects the selection + * of the performance domain frequency. + * NOTE: in case RT tasks are running, by default the + * FREQUENCY_UTIL's utilization can be max OPP. + */ + tsk = cpu == dst_cpu ? p : NULL; + cpu_util = schedutil_cpu_util(cpu, util_cfs, cpu_cap, + FREQUENCY_UTIL, tsk); + max_util = max(max_util, cpu_util); }
That's a bit unfortunate; having to do both variants here, but I see why. Nothing to be done about it I suppose.