diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index 7c4ce69067c4..d84e036a7536 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -202,8 +202,10 @@ unsigned long schedutil_freq_util(int cpu, unsigned long util_cfs, unsigned long dl_util, util, irq; struct rq *rq = cpu_rq(cpu); - if (type == FREQUENCY_UTIL && rt_rq_is_runnable(&rq->rt)) + if (!IS_BUILTIN(CONFIG_UCLAMP_TASK) && + type == FREQUENCY_UTIL && rt_rq_is_runnable(&rq->rt)) { return max; + } /* * Early check to see if IRQ/steal time saturates the CPU, can be @@ -219,9 +221,16 @@ unsigned long schedutil_freq_util(int cpu, unsigned long util_cfs, * 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; - util += cpu_util_rt(rq); + util = util_cfs + cpu_util_rt(rq); + if (type == FREQUENCY_UTIL) + util = uclamp_util(rq, util); dl_util = cpu_util_dl(rq); diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 3bdcd3c718bc..28db7ce5c3a6 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -10393,6 +10393,10 @@ const struct sched_class fair_sched_class = { #ifdef CONFIG_FAIR_GROUP_SCHED .task_change_group = task_change_group_fair, #endif + +#ifdef CONFIG_UCLAMP_TASK + .uclamp_enabled = 1, +#endif }; #ifdef CONFIG_SCHED_DEBUG diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 63ad7c90822c..a532558a5176 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -2400,6 +2400,10 @@ const struct sched_class rt_sched_class = { .switched_to = switched_to_rt, .update_curr = update_curr_rt, + +#ifdef CONFIG_UCLAMP_TASK + .uclamp_enabled = 1, +#endif }; #ifdef CONFIG_RT_GROUP_SCHED diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 0d2ba8bb2cb3..9b0c77a99346 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -2265,6 +2265,29 @@ static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {} #endif /* CONFIG_CPU_FREQ */ +#ifdef CONFIG_UCLAMP_TASK +static inline unsigned int uclamp_util(struct rq *rq, unsigned int util) +{ + unsigned int min_util = READ_ONCE(rq->uclamp[UCLAMP_MIN].value); + unsigned int max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value); + + /* + * Since CPU's {min,max}_util clamps are MAX aggregated considering + * RUNNABLE tasks with _different_ clamps, we can end up with an + * inversion. Fix it now when the clamps are applied. + */ + if (unlikely(min_util >= max_util)) + return min_util; + + return clamp(util, min_util, max_util); +} +#else /* CONFIG_UCLAMP_TASK */ +static inline unsigned int uclamp_util(struct rq *rq, unsigned int util) +{ + return util; +} +#endif /* CONFIG_UCLAMP_TASK */ + #ifdef arch_scale_freq_capacity # ifndef arch_scale_freq_invariant # define arch_scale_freq_invariant() true