Re: [PATCH v3 06/14] sched/cpufreq: uclamp: add utilization clamping for RT tasks
From: Quentin Perret <hidden>
Date: 2018-08-07 13:54:14
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Hi Patrick, On Monday 06 Aug 2018 at 17:39:38 (+0100), Patrick Bellasi wrote:
quoted hunk ↗ jump to hunk
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index a7affc729c25..bb25ef66c2d3 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c@@ -200,6 +200,7 @@ static unsigned int get_next_freq(struct sugov_policy *sg_policy, static unsigned long sugov_get_util(struct sugov_cpu *sg_cpu) { struct rq *rq = cpu_rq(sg_cpu->cpu); + unsigned long util_cfs, util_rt; unsigned long util, irq, max; sg_cpu->max = max = arch_scale_cpu_capacity(NULL, sg_cpu->cpu);
IIUC, not far below this you should still have something like: if (rt_rq_is_runnable(&rq->rt)) return max; So you won't reach the actual clamping code at the end of the function when a RT task is runnable no? Also, I always had the feeling that the default for RT should be util_min == 1024, and then users could decide to lower the bar if they want to. For the specific case of RT, that feels more natural than applying a max util clamp IMO. What do you think ? Thanks, Quentin