Commit 7d6a905f authored by Viresh Kumar's avatar Viresh Kumar Committed by Peter Zijlstra

sched/core: Move schedutil_cpu_util() to core.c

There is nothing schedutil specific in schedutil_cpu_util(), move it to
core.c and define it only for CONFIG_SMP.
Signed-off-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/c921a362c78e1324f8ebc5aaa12f53e309c5a8a2.1607400596.git.viresh.kumar@linaro.org
parent e71ba945
...@@ -5662,6 +5662,114 @@ struct task_struct *idle_task(int cpu) ...@@ -5662,6 +5662,114 @@ struct task_struct *idle_task(int cpu)
return cpu_rq(cpu)->idle; return cpu_rq(cpu)->idle;
} }
#ifdef CONFIG_SMP
/*
* 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);
}
#endif /* CONFIG_SMP */
/** /**
* find_process_by_pid - find a process with a matching PID value. * find_process_by_pid - find a process with a matching PID value.
* @pid: the pid in question. * @pid: the pid in question.
......
...@@ -171,112 +171,6 @@ static unsigned int get_next_freq(struct sugov_policy *sg_policy, ...@@ -171,112 +171,6 @@ static unsigned int get_next_freq(struct sugov_policy *sg_policy,
return cpufreq_driver_resolve_freq(policy, freq); 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) static void sugov_get_util(struct sugov_cpu *sg_cpu)
{ {
struct rq *rq = cpu_rq(sg_cpu->cpu); struct rq *rq = cpu_rq(sg_cpu->cpu);
......
...@@ -2557,7 +2557,6 @@ static inline unsigned long capacity_orig_of(int cpu) ...@@ -2557,7 +2557,6 @@ static inline unsigned long capacity_orig_of(int cpu)
{ {
return cpu_rq(cpu)->cpu_capacity_orig; return cpu_rq(cpu)->cpu_capacity_orig;
} }
#endif
/** /**
* enum schedutil_type - CPU utilization type * enum schedutil_type - CPU utilization type
...@@ -2574,8 +2573,6 @@ enum schedutil_type { ...@@ -2574,8 +2573,6 @@ enum schedutil_type {
ENERGY_UTIL, ENERGY_UTIL,
}; };
#ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs, unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
unsigned long max, enum schedutil_type type, unsigned long max, enum schedutil_type type,
struct task_struct *p); struct task_struct *p);
...@@ -2606,14 +2603,7 @@ static inline unsigned long cpu_util_rt(struct rq *rq) ...@@ -2606,14 +2603,7 @@ static inline unsigned long cpu_util_rt(struct rq *rq)
{ {
return READ_ONCE(rq->avg_rt.util_avg); return READ_ONCE(rq->avg_rt.util_avg);
} }
#else /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */ #endif
static inline unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
unsigned long max, enum schedutil_type type,
struct task_struct *p)
{
return 0;
}
#endif /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
#ifdef CONFIG_HAVE_SCHED_AVG_IRQ #ifdef CONFIG_HAVE_SCHED_AVG_IRQ
static inline unsigned long cpu_util_irq(struct rq *rq) static inline unsigned long cpu_util_irq(struct rq *rq)
......
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