[PATCH 1/2] sched/fair: Use weight of SD_NUMA domain in find_busiest_group

From: Mel Gorman <mgorman@techsingularity.net>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Valentin Schneider <valentin.schneider@arm.com>,
	Aubrey Li <aubrey.li@linux.intel.com>,
	Barry Song <song.bao.hua@hisilicon.com>,
	Mike Galbraith <efault@gmx.de>,
	Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Mel Gorman <mgorman@techsingularity.net>
Subject: [PATCH 1/2] sched/fair: Use weight of SD_NUMA domain in find_busiest_group
Date: Wed,  1 Dec 2021 15:18:43 +0000	[thread overview]
Message-ID: <20211201151844.20488-2-mgorman@techsingularity.net> (raw)
In-Reply-To: <20211201151844.20488-1-mgorman@techsingularity.net>

find_busiest_group uses the child domain's group weight instead of
the sched_domain's weight that has SD_NUMA set when calculating the
allowed imbalance between NUMA nodes. This is wrong and inconsistent
with find_idlest_group.

This patch uses the SD_NUMA weight in both.

Fixes: c4e8f691d926 ("sched/fair: Adjust the allowed NUMA imbalance when SD_NUMA spans multiple LLCS")
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
---
 kernel/sched/fair.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 6e476f6d9435..0a969affca76 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -9397,7 +9397,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
 		/* Consider allowing a small imbalance between NUMA groups */
 		if (env->sd->flags & SD_NUMA) {
 			env->imbalance = adjust_numa_imbalance(env->imbalance,
-				busiest->sum_nr_running, busiest->group_weight);
+				busiest->sum_nr_running, env->sd->span_weight);
 		}
 
 		return;
-- 
2.31.1

