From 9e91d61d9b0ca8d865dbd59af8d0d5c5b68003e9 Mon Sep 17 00:00:00 2001 From: Dietmar Eggemann Date: Fri, 14 Aug 2015 17:23:12 +0100 Subject: [PATCH] sched/fair: Name utilization related data and functions consistently Use the advent of the per-entity load tracking rewrite to streamline the naming of utilization related data and functions by using {prefix_}util{_suffix} consistently. Moreover call both signals ({se,cfs}.avg.util_avg) utilization. Signed-off-by: Dietmar Eggemann Signed-off-by: Morten Rasmussen Signed-off-by: Peter Zijlstra (Intel) Cc: Dietmar Eggemann Cc: Juri Lelli Cc: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: daniel.lezcano@linaro.org Cc: mturquette@baylibre.com Cc: pang.xunlei@zte.com.cn Cc: rjw@rjwysocki.net Cc: sgurrappadi@nvidia.com Cc: vincent.guittot@linaro.org Cc: yuyang.du@intel.com Link: http://lkml.kernel.org/r/1439569394-11974-5-git-send-email-morten.rasmussen@arm.com Signed-off-by: Ingo Molnar --- kernel/sched/fair.c | 37 +++++++++++++++++++------------------ 1 file changed, 19 insertions(+), 18 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 573dc98c6248..1b56d63c5322 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4863,31 +4863,32 @@ done: return target; } /* - * get_cpu_usage returns the amount of capacity of a CPU that is used by CFS + * 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 usage with the capacity of the CPU that is available for CFS - * task (ie cpu_capacity). + * compare the utilization with the capacity of the CPU that is available for + * CFS task (ie cpu_capacity). * cfs.avg.util_avg is the sum of running time of runnable tasks on a * CPU. It represents the amount of utilization of a CPU in the range - * [0..SCHED_LOAD_SCALE]. The usage of a CPU can't be higher than the full - * capacity of the CPU because it's about the running time on this CPU. + * [0..SCHED_LOAD_SCALE]. The utilization of a CPU can't be higher than the + * full capacity of the CPU because it's about the running time on this CPU. * Nevertheless, cfs.avg.util_avg can be higher than SCHED_LOAD_SCALE * because of unfortunate rounding in util_avg or just * after migrating tasks until the average stabilizes with the new running - * time. So we need to check that the usage stays into the range + * time. So we need to check that the utilization stays into the range * [0..cpu_capacity_orig] and cap if necessary. - * Without capping the usage, a group could be seen as overloaded (CPU0 usage - * at 121% + CPU1 usage at 80%) whereas CPU1 has 20% of available capacity + * Without capping the utilization, a group could be seen as overloaded (CPU0 + * utilization at 121% + CPU1 utilization at 80%) whereas CPU1 has 20% of + * available capacity. */ -static int get_cpu_usage(int cpu) +static int cpu_util(int cpu) { - unsigned long usage = cpu_rq(cpu)->cfs.avg.util_avg; + unsigned long util = cpu_rq(cpu)->cfs.avg.util_avg; unsigned long capacity = capacity_orig_of(cpu); - if (usage >= SCHED_LOAD_SCALE) + if (util >= SCHED_LOAD_SCALE) return capacity; - return (usage * capacity) >> SCHED_LOAD_SHIFT; + return (util * capacity) >> SCHED_LOAD_SHIFT; } /* @@ -5979,7 +5980,7 @@ 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_usage; /* Total usage of the group */ + unsigned long group_util; /* Total utilization of the group */ unsigned int sum_nr_running; /* Nr tasks running in the group */ unsigned int idle_cpus; unsigned int group_weight; @@ -6212,8 +6213,8 @@ static inline int sg_imbalanced(struct sched_group *group) * group_has_capacity returns true if the group has spare capacity that could * be used by some tasks. * We consider that a group has spare capacity if the * number of task is - * smaller than the number of CPUs or if the usage is lower than the available - * capacity for CFS tasks. + * smaller than the number of CPUs or if the utilization is lower than the + * available capacity for CFS tasks. * For the latter, we use a threshold to stabilize the state, to take into * account the variance of the tasks' load and to return true if the available * capacity in meaningful for the load balancer. @@ -6227,7 +6228,7 @@ group_has_capacity(struct lb_env *env, struct sg_lb_stats *sgs) return true; if ((sgs->group_capacity * 100) > - (sgs->group_usage * env->sd->imbalance_pct)) + (sgs->group_util * env->sd->imbalance_pct)) return true; return false; @@ -6248,7 +6249,7 @@ group_is_overloaded(struct lb_env *env, struct sg_lb_stats *sgs) return false; if ((sgs->group_capacity * 100) < - (sgs->group_usage * env->sd->imbalance_pct)) + (sgs->group_util * env->sd->imbalance_pct)) return true; return false; @@ -6296,7 +6297,7 @@ static inline void update_sg_lb_stats(struct lb_env *env, load = source_load(i, load_idx); sgs->group_load += load; - sgs->group_usage += get_cpu_usage(i); + sgs->group_util += cpu_util(i); sgs->sum_nr_running += rq->cfs.h_nr_running; if (rq->nr_running > 1) -- 2.39.5