diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched/core.c | 41 | ||||
| -rw-r--r-- | kernel/sched/fair.c | 66 | ||||
| -rw-r--r-- | kernel/sched/sched.h | 68 |
3 files changed, 109 insertions, 66 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 569a2f0f01e4..573dcb62b3b3 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2854,6 +2854,45 @@ unsigned long long task_sched_runtime(struct task_struct *p) return ns; } +#ifdef CONFIG_CPU_FREQ_GOV_SCHED +static unsigned long sum_capacity_reqs(unsigned long cfs_cap, + struct sched_capacity_reqs *scr) +{ + unsigned long total = cfs_cap + scr->rt; + + total = total * capacity_margin; + total /= SCHED_CAPACITY_SCALE; + total += scr->dl; + return total; +} + +static void sched_freq_tick(int cpu) +{ + struct sched_capacity_reqs *scr; + unsigned long capacity_orig, capacity_curr; + + if (!sched_freq()) + return; + + capacity_orig = capacity_orig_of(cpu); + capacity_curr = capacity_curr_of(cpu); + if (capacity_curr == capacity_orig) + return; + + /* + * To make free room for a task that is building up its "real" + * utilization and to harm its performance the least, request + * a jump to max OPP as soon as the margin of free capacity is + * impacted (specified by capacity_margin). + */ + scr = &per_cpu(cpu_sched_capacity_reqs, cpu); + if (capacity_curr < sum_capacity_reqs(cpu_util(cpu), scr)) + set_cfs_cpu_capacity(cpu, true, capacity_max); +} +#else +static inline void sched_freq_tick(int cpu) { } +#endif + /* * This function gets called by the timer code, with HZ frequency. * We call it with interrupts disabled. @@ -2880,6 +2919,8 @@ void scheduler_tick(void) trigger_load_balance(rq); #endif rq_last_tick_reset(rq); + + sched_freq_tick(cpu); } #ifdef CONFIG_NO_HZ_FULL diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 8f93b23596e5..126a0116162d 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4160,9 +4160,6 @@ static inline void hrtick_update(struct rq *rq) } #endif -static unsigned long capacity_orig_of(int cpu); -static int cpu_util(int cpu); - static void update_capacity_of(int cpu) { unsigned long req_cap; @@ -4537,15 +4534,6 @@ static unsigned long target_load(int cpu, int type) return max(rq->cpu_load[type-1], total); } -static unsigned long capacity_of(int cpu) -{ - return cpu_rq(cpu)->cpu_capacity; -} - -static unsigned long capacity_orig_of(int cpu) -{ - return cpu_rq(cpu)->cpu_capacity_orig; -} static unsigned long cpu_avg_load_per_task(int cpu) { @@ -4719,60 +4707,6 @@ static long effective_load(struct task_group *tg, int cpu, long wl, long wg) #endif -/* - * Returns the current capacity of cpu after applying both - * cpu and freq scaling. - */ -static unsigned long capacity_curr_of(int cpu) -{ - return cpu_rq(cpu)->cpu_capacity_orig * - arch_scale_freq_capacity(NULL, cpu) - >> SCHED_CAPACITY_SHIFT; -} - -/* - * cpu_util returns the amount of capacity of a CPU that is used by CFS - * tasks. The unit of the return value must be the one of capacity so we can - * compare the utilization with the capacity of the CPU that is available for - * CFS task (ie cpu_capacity). - * - * cfs_rq.avg.util_avg is the sum of running time of runnable tasks plus the - * recent utilization of currently non-runnable tasks on a CPU. It represents - * the amount of utilization of a CPU in the range [0..capacity_orig] where - * capacity_orig is the cpu_capacity available at the highest frequency - * (arch_scale_freq_capacity()). - * The utilization of a CPU converges towards a sum equal to or less than the - * current capacity (capacity_curr <= capacity_orig) of the CPU because it is - * the running time on this CPU scaled by capacity_curr. - * - * Nevertheless, cfs_rq.avg.util_avg can be higher than capacity_curr or even - * higher than capacity_orig because of unfortunate rounding in - * cfs.avg.util_avg or just after migrating tasks and new task wakeups until - * the average stabilizes with the new running time. We need to check that the - * utilization stays within the range of [0..capacity_orig] and cap it if - * necessary. Without utilization capping, a group could be seen as overloaded - * (CPU0 utilization at 121% + CPU1 utilization at 80%) whereas CPU1 has 20% of - * available capacity. We allow utilization to overshoot capacity_curr (but not - * capacity_orig) as it useful for predicting the capacity required after task - * migrations (scheduler-driven DVFS). - */ -static unsigned long __cpu_util(int cpu, int delta) -{ - unsigned long util = cpu_rq(cpu)->cfs.avg.util_avg; - unsigned long capacity = capacity_orig_of(cpu); - - delta += util; - if (delta < 0) - return 0; - - return (delta >= capacity) ? capacity : delta; -} - -static unsigned long cpu_util(int cpu) -{ - return __cpu_util(cpu, 0); -} - static inline bool energy_aware(void) { return sched_feat(ENERGY_AWARE); diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index c91e85c90d5d..2f38f4978df8 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1456,7 +1456,75 @@ unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu) } #endif +#ifdef CONFIG_SMP +static inline unsigned long capacity_of(int cpu) +{ + return cpu_rq(cpu)->cpu_capacity; +} + +static inline unsigned long capacity_orig_of(int cpu) +{ + return cpu_rq(cpu)->cpu_capacity_orig; +} + +/* + * cpu_util returns the amount of capacity of a CPU that is used by CFS + * tasks. The unit of the return value must be the one of capacity so we can + * compare the utilization with the capacity of the CPU that is available for + * CFS task (ie cpu_capacity). + * + * cfs_rq.avg.util_avg is the sum of running time of runnable tasks plus the + * recent utilization of currently non-runnable tasks on a CPU. It represents + * the amount of utilization of a CPU in the range [0..capacity_orig] where + * capacity_orig is the cpu_capacity available at the highest frequency + * (arch_scale_freq_capacity()). + * The utilization of a CPU converges towards a sum equal to or less than the + * current capacity (capacity_curr <= capacity_orig) of the CPU because it is + * the running time on this CPU scaled by capacity_curr. + * + * Nevertheless, cfs_rq.avg.util_avg can be higher than capacity_curr or even + * higher than capacity_orig because of unfortunate rounding in + * cfs.avg.util_avg or just after migrating tasks and new task wakeups until + * the average stabilizes with the new running time. We need to check that the + * utilization stays within the range of [0..capacity_orig] and cap it if + * necessary. Without utilization capping, a group could be seen as overloaded + * (CPU0 utilization at 121% + CPU1 utilization at 80%) whereas CPU1 has 20% of + * available capacity. We allow utilization to overshoot capacity_curr (but not + * capacity_orig) as it useful for predicting the capacity required after task + * migrations (scheduler-driven DVFS). + */ +static inline unsigned long __cpu_util(int cpu, int delta) +{ + unsigned long util = cpu_rq(cpu)->cfs.avg.util_avg; + unsigned long capacity = capacity_orig_of(cpu); + + delta += util; + if (delta < 0) + return 0; + + return (delta >= capacity) ? capacity : delta; +} + +static inline unsigned long cpu_util(int cpu) +{ + return __cpu_util(cpu, 0); +} + +/* + * Returns the current capacity of cpu after applying both + * cpu and freq scaling. + */ +static inline unsigned long capacity_curr_of(int cpu) +{ + return cpu_rq(cpu)->cpu_capacity_orig * + arch_scale_freq_capacity(NULL, cpu) + >> SCHED_CAPACITY_SHIFT; +} + +#endif + #ifdef CONFIG_CPU_FREQ_GOV_SCHED +#define capacity_max SCHED_CAPACITY_SCALE extern unsigned int capacity_margin; extern struct static_key __sched_freq; |