Monitor the utilization level of each group of each sched_domain level. The utilization 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 utilization 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 | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index bdc5cb9..a6b4b25 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4047,6 +4047,11 @@ 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) { struct rq *rq = cpu_rq(cpu); @@ -4437,6 +4442,18 @@ done: return target; }
+static int get_cpu_utilization(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 capacity_orig_of(cpu) + 1; + + return (sum * capacity_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, @@ -5517,6 +5534,7 @@ struct sg_lb_stats { unsigned long sum_weighted_load; /* Weighted load of group's tasks */ unsigned long load_per_task; unsigned long group_capacity; + unsigned long group_utilization; /* Total utilization of the group */ unsigned int sum_nr_running; /* Nr tasks running in the group */ unsigned int group_capacity_factor; unsigned int idle_cpus; @@ -5876,6 +5894,7 @@ static inline void update_sg_lb_stats(struct lb_env *env, load = source_load(i, load_idx);
sgs->group_load += load; + sgs->group_utilization += get_cpu_utilization(i); sgs->sum_nr_running += rq->cfs.h_nr_running; #ifdef CONFIG_NUMA_BALANCING sgs->nr_numa_running += rq->nr_numa_running; @@ -6043,7 +6062,6 @@ next_group: /* Now, start updating sd_lb_stats */ sds->total_load += sgs->group_load; sds->total_capacity += sgs->group_capacity; - sg = sg->next; } while (sg != env->sd->groups);