Monitor the activity level of each group of each sched_domain level. The activity is the amount of cpu_power that is currently used on a CPU or group of CPUs. We use the runnable_avg_sum and _period to evaluate this activity level. In the special use case where the CPU is fully loaded by more than 1 task, the activity level is set above the cpu_power in order to reflect the overload of the CPU
Signed-off-by: Vincent Guittot vincent.guittot@linaro.org --- kernel/sched/fair.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index b7c51be..c01d8b6 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4044,6 +4044,11 @@ static unsigned long power_of(int cpu) return cpu_rq(cpu)->cpu_power; }
+static unsigned long power_orig_of(int cpu) +{ + return cpu_rq(cpu)->cpu_power_orig; +} + static unsigned long cpu_avg_load_per_task(int cpu) { struct rq *rq = cpu_rq(cpu); @@ -4438,6 +4443,18 @@ done: return target; }
+static int get_cpu_activity(int cpu) +{ + struct rq *rq = cpu_rq(cpu); + u32 sum = rq->avg.runnable_avg_sum; + u32 period = rq->avg.runnable_avg_period; + + if (sum >= period) + return power_orig_of(cpu) + rq->nr_running - 1; + + return (sum * power_orig_of(cpu)) / period; +} + /* * select_task_rq_fair: Select target runqueue for the waking task in domains * that have the 'sd_flag' flag set. In practice, this is SD_BALANCE_WAKE, @@ -5518,6 +5535,7 @@ struct sg_lb_stats { unsigned long sum_weighted_load; /* Weighted load of group's tasks */ unsigned long load_per_task; unsigned long group_power; + unsigned long group_activity; /* Total activity of the group */ unsigned int sum_nr_running; /* Nr tasks running in the group */ unsigned int group_capacity; unsigned int idle_cpus; @@ -5538,6 +5556,7 @@ struct sd_lb_stats { struct sched_group *busiest; /* Busiest group in this sd */ struct sched_group *local; /* Local group in this sd */ unsigned long total_load; /* Total load of all groups in sd */ + unsigned long total_activity; /* Total activity of all groups in sd */ unsigned long total_pwr; /* Total power of all groups in sd */ unsigned long avg_load; /* Average load across all groups in sd */
@@ -5557,6 +5576,7 @@ static inline void init_sd_lb_stats(struct sd_lb_stats *sds) .busiest = NULL, .local = NULL, .total_load = 0UL, + .total_activity = 0UL, .total_pwr = 0UL, .busiest_stat = { .avg_load = 0UL, @@ -5876,6 +5896,7 @@ static inline void update_sg_lb_stats(struct lb_env *env, load = source_load(i, load_idx);
sgs->group_load += load; + sgs->group_activity += get_cpu_activity(i); sgs->sum_nr_running += rq->cfs.h_nr_running; #ifdef CONFIG_NUMA_BALANCING sgs->nr_numa_running += rq->nr_numa_running; @@ -6034,6 +6055,7 @@ static inline void update_sd_lb_stats(struct lb_env *env, struct sd_lb_stats *sd next_group: /* Now, start updating sd_lb_stats */ sds->total_load += sgs->group_load; + sds->total_activity += sgs->group_activity; sds->total_pwr += sgs->group_power;
sg = sg->next;