From a658353167bf2ea6052cee071dbcc13e0f229dc9 Mon Sep 17 00:00:00 2001 From: Tao Zhou Date: Fri, 15 Apr 2022 17:55:04 +0800 Subject: sched/fair: Revise comment about lb decision matrix If busiest group type is group_misfit_task, the local group type must be group_has_spare according to below code in update_sd_pick_busiest(): if (sgs->group_type == group_misfit_task && (!capacity_greater(capacity_of(env->dst_cpu), sg->sgc->max_capacity) || sds->local_stat.group_type != group_has_spare)) return false; group type imbalanced and overloaded and fully_busy are filtered in here. misfit and asym are filtered before in update_sg_lb_stats(). So, change the decision matrix to: busiest \ local has_spare fully_busy misfit asym imbalanced overloaded has_spare nr_idle balanced N/A N/A balanced balanced fully_busy nr_idle nr_idle N/A N/A balanced balanced misfit_task force N/A N/A N/A *N/A* *N/A* asym_packing force force N/A N/A force force imbalanced force force N/A N/A force force overloaded force force N/A N/A force avg_load Fixes: 0b0695f2b34a ("sched/fair: Rework load_balance()") Signed-off-by: Tao Zhou Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Dietmar Eggemann Reviewed-by: Vincent Guittot Link: https://lkml.kernel.org/r/20220415095505.7765-1-tao.zhou@linux.dev --- kernel/sched/fair.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/sched') diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 3eba0dcc4962..4c420124b5d6 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -9496,7 +9496,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s * busiest \ local has_spare fully_busy misfit asym imbalanced overloaded * has_spare nr_idle balanced N/A N/A balanced balanced * fully_busy nr_idle nr_idle N/A N/A balanced balanced - * misfit_task force N/A N/A N/A force force + * misfit_task force N/A N/A N/A N/A N/A * asym_packing force force N/A N/A force force * imbalanced force force N/A N/A force force * overloaded force force N/A N/A force avg_load -- cgit v1.2.3