From 0fedc6c8e34f4ce0b37b1f25c3619b4a8faa244c Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Mon, 26 May 2014 18:19:36 -0400 Subject: [PATCH] sched/fair: Disambiguate existing/remaining "capacity" usage We have "power" (which should actually become "capacity") and "capacity" which is a scaled down "capacity factor" in terms of unitary tasks. Let's use "capacity_factor" to make room for proper usage of "capacity" later. Signed-off-by: Nicolas Pitre Signed-off-by: Peter Zijlstra Cc: Vincent Guittot Cc: Daniel Lezcano Cc: Morten Rasmussen Cc: "Rafael J. Wysocki" Cc: linaro-kernel@lists.linaro.org Cc: Linus Torvalds Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/n/tip-gk1co8sqdev3763opqm6ovml@git.kernel.org Signed-off-by: Ingo Molnar --- kernel/sched/fair.c | 42 +++++++++++++++++++++--------------------- 1 file changed, 21 insertions(+), 21 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 8993dfa2e82b..e401e446e87c 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5534,7 +5534,7 @@ struct sg_lb_stats { unsigned long load_per_task; unsigned long group_power; unsigned int sum_nr_running; /* Nr tasks running in the group */ - unsigned int group_capacity; + unsigned int group_capacity_factor; unsigned int idle_cpus; unsigned int group_weight; int group_imb; /* Is there an imbalance in the group ? */ @@ -5829,15 +5829,15 @@ static inline int sg_imbalanced(struct sched_group *group) } /* - * Compute the group capacity. + * Compute the group capacity factor. * * Avoid the issue where N*frac(smt_power) >= 1 creates 'phantom' cores by * first dividing out the smt factor and computing the actual number of cores * and limit power unit capacity with that. */ -static inline int sg_capacity(struct lb_env *env, struct sched_group *group) +static inline int sg_capacity_factor(struct lb_env *env, struct sched_group *group) { - unsigned int capacity, smt, cpus; + unsigned int capacity_factor, smt, cpus; unsigned int power, power_orig; power = group->sgp->power; @@ -5846,13 +5846,13 @@ static inline int sg_capacity(struct lb_env *env, struct sched_group *group) /* smt := ceil(cpus / power), assumes: 1 < smt_power < 2 */ smt = DIV_ROUND_UP(SCHED_POWER_SCALE * cpus, power_orig); - capacity = cpus / smt; /* cores */ + capacity_factor = cpus / smt; /* cores */ - capacity = min_t(unsigned, capacity, DIV_ROUND_CLOSEST(power, SCHED_POWER_SCALE)); - if (!capacity) - capacity = fix_small_capacity(env->sd, group); + capacity_factor = min_t(unsigned, capacity_factor, DIV_ROUND_CLOSEST(power, SCHED_POWER_SCALE)); + if (!capacity_factor) + capacity_factor = fix_small_capacity(env->sd, group); - return capacity; + return capacity_factor; } /** @@ -5902,9 +5902,9 @@ static inline void update_sg_lb_stats(struct lb_env *env, sgs->group_weight = group->group_weight; sgs->group_imb = sg_imbalanced(group); - sgs->group_capacity = sg_capacity(env, group); + sgs->group_capacity_factor = sg_capacity_factor(env, group); - if (sgs->group_capacity > sgs->sum_nr_running) + if (sgs->group_capacity_factor > sgs->sum_nr_running) sgs->group_has_free_capacity = 1; } @@ -5929,7 +5929,7 @@ static bool update_sd_pick_busiest(struct lb_env *env, if (sgs->avg_load <= sds->busiest_stat.avg_load) return false; - if (sgs->sum_nr_running > sgs->group_capacity) + if (sgs->sum_nr_running > sgs->group_capacity_factor) return true; if (sgs->group_imb) @@ -6020,17 +6020,17 @@ static inline void update_sd_lb_stats(struct lb_env *env, struct sd_lb_stats *sd /* * In case the child domain prefers tasks go to siblings - * first, lower the sg capacity to one so that we'll try + * first, lower the sg capacity factor to one so that we'll try * and move all the excess tasks away. We lower the capacity * of a group only if the local group has the capacity to fit - * these excess tasks, i.e. nr_running < group_capacity. The + * these excess tasks, i.e. nr_running < group_capacity_factor. The * extra check prevents the case where you always pull from the * heaviest group when it is already under-utilized (possible * with a large weight task outweighs the tasks on the system). */ if (prefer_sibling && sds->local && sds->local_stat.group_has_free_capacity) - sgs->group_capacity = min(sgs->group_capacity, 1U); + sgs->group_capacity_factor = min(sgs->group_capacity_factor, 1U); if (update_sd_pick_busiest(env, sds, sg, sgs)) { sds->busiest = sg; @@ -6204,7 +6204,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s * have to drop below capacity to reach cpu-load equilibrium. */ load_above_capacity = - (busiest->sum_nr_running - busiest->group_capacity); + (busiest->sum_nr_running - busiest->group_capacity_factor); load_above_capacity *= (SCHED_LOAD_SCALE * SCHED_POWER_SCALE); load_above_capacity /= busiest->group_power; @@ -6348,7 +6348,7 @@ static struct rq *find_busiest_queue(struct lb_env *env, int i; for_each_cpu_and(i, sched_group_cpus(group), env->cpus) { - unsigned long power, capacity, wl; + unsigned long power, capacity_factor, wl; enum fbq_type rt; rq = cpu_rq(i); @@ -6377,9 +6377,9 @@ static struct rq *find_busiest_queue(struct lb_env *env, continue; power = power_of(i); - capacity = DIV_ROUND_CLOSEST(power, SCHED_POWER_SCALE); - if (!capacity) - capacity = fix_small_capacity(env->sd, group); + capacity_factor = DIV_ROUND_CLOSEST(power, SCHED_POWER_SCALE); + if (!capacity_factor) + capacity_factor = fix_small_capacity(env->sd, group); wl = weighted_cpuload(i); @@ -6387,7 +6387,7 @@ static struct rq *find_busiest_queue(struct lb_env *env, * When comparing with imbalance, use weighted_cpuload() * which is not scaled with the cpu power. */ - if (capacity && rq->nr_running == 1 && wl > env->imbalance) + if (capacity_factor && rq->nr_running == 1 && wl > env->imbalance) continue; /*