Commit-ID: 3ae11c90fd055ba1b1b03a014f851b395bdd26ff Gitweb: http://git.kernel.org/tip/3ae11c90fd055ba1b1b03a014f851b395bdd26ff Author: Peter Zijlstra <pet...@infradead.org> AuthorDate: Thu, 15 Aug 2013 20:37:48 +0200 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Mon, 2 Sep 2013 08:27:37 +0200
sched/fair: Make group power more consistent For easier access, less dereferences and more consistent value, store the group power in update_sg_lb_stats() and use it thereafter. The actual value in sched_group::sched_group_power::power can change throughout the load-balance pass if we're unlucky. Reviewed-by: Preeti U Murthy <pre...@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <pet...@infradead.org> Link: http://lkml.kernel.org/n/tip-739xxqkyvftrhnh9ncudu...@git.kernel.org Signed-off-by: Ingo Molnar <mi...@kernel.org> --- kernel/sched/fair.c | 41 ++++++++++++++++++++++------------------- 1 file changed, 22 insertions(+), 19 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 5795219..ccf20e7 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4239,6 +4239,7 @@ struct sg_lb_stats { unsigned long group_load; /* Total load over the CPUs of the group */ unsigned long sum_weighted_load; /* Weighted load of group's tasks */ 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 idle_cpus; @@ -4518,7 +4519,8 @@ static inline void update_sg_lb_stats(struct lb_env *env, update_group_power(env->sd, env->dst_cpu); /* Adjust by relative CPU power of the group */ - sgs->avg_load = (sgs->group_load*SCHED_POWER_SCALE) / group->sgp->power; + sgs->group_power = group->sgp->power; + sgs->avg_load = (sgs->group_load*SCHED_POWER_SCALE) / sgs->group_power; /* * Consider the group unbalanced when the imbalance is larger @@ -4537,7 +4539,7 @@ static inline void update_sg_lb_stats(struct lb_env *env, sgs->group_imb = 1; sgs->group_capacity = - DIV_ROUND_CLOSEST(group->sgp->power, SCHED_POWER_SCALE); + DIV_ROUND_CLOSEST(sgs->group_power, SCHED_POWER_SCALE); if (!sgs->group_capacity) sgs->group_capacity = fix_small_capacity(env->sd, group); @@ -4637,7 +4639,7 @@ static inline void update_sd_lb_stats(struct lb_env *env, /* Now, start updating sd_lb_stats */ sds->total_load += sgs->group_load; - sds->total_pwr += sg->sgp->power; + sds->total_pwr += sgs->group_power; if (!local_group && update_sd_pick_busiest(env, sds, sg, sgs)) { sds->busiest = sg; @@ -4685,8 +4687,9 @@ static int check_asym_packing(struct lb_env *env, struct sd_lb_stats *sds) if (env->dst_cpu > busiest_cpu) return 0; - env->imbalance = DIV_ROUND_CLOSEST(sds->busiest_stat.avg_load * - sds->busiest->sgp->power, SCHED_POWER_SCALE); + env->imbalance = DIV_ROUND_CLOSEST( + sds->busiest_stat.avg_load * sds->busiest_stat.group_power, + SCHED_POWER_SCALE); return 1; } @@ -4716,7 +4719,7 @@ void fix_small_imbalance(struct lb_env *env, struct sd_lb_stats *sds) scaled_busy_load_per_task = (busiest->load_per_task * SCHED_POWER_SCALE) / - sds->busiest->sgp->power; + busiest->group_power; if (busiest->avg_load - local->avg_load + scaled_busy_load_per_task >= (scaled_busy_load_per_task * imbn)) { @@ -4730,32 +4733,32 @@ void fix_small_imbalance(struct lb_env *env, struct sd_lb_stats *sds) * moving them. */ - pwr_now += sds->busiest->sgp->power * + pwr_now += busiest->group_power * min(busiest->load_per_task, busiest->avg_load); - pwr_now += sds->local->sgp->power * + pwr_now += local->group_power * min(local->load_per_task, local->avg_load); pwr_now /= SCHED_POWER_SCALE; /* Amount of load we'd subtract */ tmp = (busiest->load_per_task * SCHED_POWER_SCALE) / - sds->busiest->sgp->power; + busiest->group_power; if (busiest->avg_load > tmp) { - pwr_move += sds->busiest->sgp->power * + pwr_move += busiest->group_power * min(busiest->load_per_task, busiest->avg_load - tmp); } /* Amount of load we'd add */ - if (busiest->avg_load * sds->busiest->sgp->power < + if (busiest->avg_load * busiest->group_power < busiest->load_per_task * SCHED_POWER_SCALE) { - tmp = (busiest->avg_load * sds->busiest->sgp->power) / - sds->local->sgp->power; + tmp = (busiest->avg_load * busiest->group_power) / + local->group_power; } else { tmp = (busiest->load_per_task * SCHED_POWER_SCALE) / - sds->local->sgp->power; + local->group_power; } - pwr_move += sds->local->sgp->power * - min(local->load_per_task, local->avg_load + tmp); + pwr_move += local->group_power * + min(local->load_per_task, local->avg_load + tmp); pwr_move /= SCHED_POWER_SCALE; /* Move if we gain throughput */ @@ -4800,7 +4803,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s (busiest->sum_nr_running - busiest->group_capacity); load_above_capacity *= (SCHED_LOAD_SCALE * SCHED_POWER_SCALE); - load_above_capacity /= sds->busiest->sgp->power; + load_above_capacity /= busiest->group_power; } /* @@ -4818,8 +4821,8 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s /* How much load to actually move to equalise the imbalance */ env->imbalance = min( - max_pull * sds->busiest->sgp->power, - (sds->avg_load - local->avg_load) * sds->local->sgp->power + max_pull * busiest->group_power, + (sds->avg_load - local->avg_load) * local->group_power ) / SCHED_POWER_SCALE; /* -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
