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Diffstat (limited to 'kernel/sched/cpufreq_schedutil.c')
-rw-r--r--kernel/sched/cpufreq_schedutil.c108
1 files changed, 1 insertions, 107 deletions
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index 6931f0cdeb80..41e498b0008a 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -171,112 +171,6 @@ static unsigned int get_next_freq(struct sugov_policy *sg_policy,
return cpufreq_driver_resolve_freq(policy, freq);
}
-/*
- * This function computes an effective utilization for the given CPU, to be
- * used for frequency selection given the linear relation: f = u * f_max.
- *
- * The scheduler tracks the following metrics:
- *
- * cpu_util_{cfs,rt,dl,irq}()
- * cpu_bw_dl()
- *
- * Where the cfs,rt and dl util numbers are tracked with the same metric and
- * synchronized windows and are thus directly comparable.
- *
- * The cfs,rt,dl utilization are the running times measured with rq->clock_task
- * which excludes things like IRQ and steal-time. These latter are then accrued
- * in the irq utilization.
- *
- * The DL bandwidth number otoh is not a measured metric but a value computed
- * based on the task model parameters and gives the minimal utilization
- * required to meet deadlines.
- */
-unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
- unsigned long max, enum schedutil_type type,
- struct task_struct *p)
-{
- unsigned long dl_util, util, irq;
- struct rq *rq = cpu_rq(cpu);
-
- if (!uclamp_is_used() &&
- type == FREQUENCY_UTIL && rt_rq_is_runnable(&rq->rt)) {
- return max;
- }
-
- /*
- * Early check to see if IRQ/steal time saturates the CPU, can be
- * because of inaccuracies in how we track these -- see
- * update_irq_load_avg().
- */
- irq = cpu_util_irq(rq);
- if (unlikely(irq >= max))
- return max;
-
- /*
- * Because the time spend on RT/DL tasks is visible as 'lost' time to
- * CFS tasks and we use the same metric to track the effective
- * utilization (PELT windows are synchronized) we can directly add them
- * to obtain the CPU's actual utilization.
- *
- * CFS and RT utilization can be boosted or capped, depending on
- * utilization clamp constraints requested by currently RUNNABLE
- * tasks.
- * When there are no CFS RUNNABLE tasks, clamps are released and
- * frequency will be gracefully reduced with the utilization decay.
- */
- util = util_cfs + cpu_util_rt(rq);
- if (type == FREQUENCY_UTIL)
- util = uclamp_rq_util_with(rq, util, p);
-
- dl_util = cpu_util_dl(rq);
-
- /*
- * For frequency selection we do not make cpu_util_dl() a permanent part
- * of this sum because we want to use cpu_bw_dl() later on, but we need
- * to check if the CFS+RT+DL sum is saturated (ie. no idle time) such
- * that we select f_max when there is no idle time.
- *
- * NOTE: numerical errors or stop class might cause us to not quite hit
- * saturation when we should -- something for later.
- */
- if (util + dl_util >= max)
- return max;
-
- /*
- * OTOH, for energy computation we need the estimated running time, so
- * include util_dl and ignore dl_bw.
- */
- if (type == ENERGY_UTIL)
- util += dl_util;
-
- /*
- * There is still idle time; further improve the number by using the
- * irq metric. Because IRQ/steal time is hidden from the task clock we
- * need to scale the task numbers:
- *
- * max - irq
- * U' = irq + --------- * U
- * max
- */
- util = scale_irq_capacity(util, irq, max);
- util += irq;
-
- /*
- * Bandwidth required by DEADLINE must always be granted while, for
- * FAIR and RT, we use blocked utilization of IDLE CPUs as a mechanism
- * to gracefully reduce the frequency when no tasks show up for longer
- * periods of time.
- *
- * Ideally we would like to set bw_dl as min/guaranteed freq and util +
- * bw_dl as requested freq. However, cpufreq is not yet ready for such
- * an interface. So, we only do the latter for now.
- */
- if (type == FREQUENCY_UTIL)
- util += cpu_bw_dl(rq);
-
- return min(max, util);
-}
-
static void sugov_get_util(struct sugov_cpu *sg_cpu)
{
struct rq *rq = cpu_rq(sg_cpu->cpu);
@@ -284,7 +178,7 @@ static void sugov_get_util(struct sugov_cpu *sg_cpu)
sg_cpu->max = max;
sg_cpu->bw_dl = cpu_bw_dl(rq);
- sg_cpu->util = schedutil_cpu_util(sg_cpu->cpu, cpu_util_cfs(rq), max,
+ sg_cpu->util = effective_cpu_util(sg_cpu->cpu, cpu_util_cfs(rq), max,
FREQUENCY_UTIL, NULL);
}