linux-kernel - [PATCH 3/7] sched,numa: use effective

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1403538095-31256-4-git-send-email-riel@redhat.com>
Date:	Mon, 23 Jun 2014 11:41:31 -0400
From:	riel@...hat.com
To:	linux-kernel@...r.kernel.org
Cc:	chegu_vinod@...com, peterz@...radead.com, mgorman@...e.de,
	mingo@...nel.org
Subject: [PATCH 3/7] sched,numa: use effective_load to balance NUMA loads

From: Rik van Riel <riel@...hat.com>

When CONFIG_FAIR_GROUP_SCHED is enabled, the load that a task places
on a CPU is determined by the group the task is in. This is conveniently
calculated for us by effective_load(), which task_numa_compare should
use.

The active groups on the source and destination CPU can be different,
so the calculation needs to be done separately for each CPU.

Signed-off-by: Rik van Riel <riel@...hat.com>
---
 kernel/sched/fair.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 612c963..41b75a6 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -1151,6 +1151,7 @@ static void task_numa_compare(struct task_numa_env *env,
 	struct rq *src_rq = cpu_rq(env->src_cpu);
 	struct rq *dst_rq = cpu_rq(env->dst_cpu);
 	struct task_struct *cur;
+	struct task_group *tg;
 	long src_load, dst_load;
 	long load;
 	long imp = (groupimp > 0) ? groupimp : taskimp;
@@ -1225,14 +1226,21 @@ static void task_numa_compare(struct task_numa_env *env,
 	 * In the overloaded case, try and keep the load balanced.
 	 */
 balance:
+	src_load = env->src_stats.load;
+	dst_load = env->dst_stats.load;
+
+	/* Calculate the effect of moving env->p from src to dst. */
 	load = task_h_load(env->p);
-	dst_load = env->dst_stats.load + load;
-	src_load = env->src_stats.load - load;
+	tg = task_group(env->p);
+	src_load += effective_load(tg, env->src_cpu, -load, -load);
+	dst_load += effective_load(tg, env->dst_cpu, load, load);
 
 	if (cur) {
+		/* Cur moves in the opposite direction. */
 		load = task_h_load(cur);
-		dst_load -= load;
-		src_load += load;
+		tg = task_group(cur);
+		src_load += effective_load(tg, env->src_cpu, load, load);
+		dst_load += effective_load(tg, env->dst_cpu, -load, -load);
 	}
 
 	if (load_too_imbalanced(src_load, dst_load, env))
-- 
1.8.5.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/