linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Vincent Guittot <vincent.guittot@linaro.org>
To: linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org
Cc: pauld@redhat.com, valentin.schneider@arm.com,
	srikar@linux.vnet.ibm.com, quentin.perret@arm.com,
	dietmar.eggemann@arm.com, Morten.Rasmussen@arm.com,
	hdanton@sina.com, parth@linux.ibm.com, riel@surriel.com,
	Vincent Guittot <vincent.guittot@linaro.org>
Subject: [PATCH v4 08/11] sched/fair: use utilization to select misfit task
Date: Fri, 18 Oct 2019 15:26:35 +0200	[thread overview]
Message-ID: <1571405198-27570-9-git-send-email-vincent.guittot@linaro.org> (raw)
In-Reply-To: <1571405198-27570-1-git-send-email-vincent.guittot@linaro.org>

utilization is used to detect a misfit task but the load is then used to
select the task on the CPU which can lead to select a small task with
high weight instead of the task that triggered the misfit migration.

Check that task can't fit the CPU's capacity when selecting the misfit
task instead of using the load.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Valentin Schneider <valentin.schneider@arm.com>
---
 kernel/sched/fair.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 9b8e20d..670856d 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -7418,13 +7418,8 @@ static int detach_tasks(struct lb_env *env)
 			break;
 
 		case migrate_misfit:
-			load = task_h_load(p);
-
-			/*
-			 * load of misfit task might decrease a bit since it has
-			 * been recorded. Be conservative in the condition.
-			 */
-			if (load / 2 < env->imbalance)
+			/* This is not a misfit task */
+			if (task_fits_capacity(p, capacity_of(env->src_cpu)))
 				goto next;
 
 			env->imbalance = 0;
@@ -8368,7 +8363,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
 	if (busiest->group_type == group_misfit_task) {
 		/* Set imbalance to allow misfit task to be balanced. */
 		env->migration_type = migrate_misfit;
-		env->imbalance = busiest->group_misfit_task_load;
+		env->imbalance = 1;
 		return;
 	}
 
-- 
2.7.4


  parent reply	other threads:[~2019-10-18 13:27 UTC|newest]

Thread overview: 89+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-18 13:26 [PATCH v4 00/10] sched/fair: rework the CFS load balance Vincent Guittot
2019-10-18 13:26 ` [PATCH v4 01/11] sched/fair: clean up asym packing Vincent Guittot
2019-10-21  9:12   ` [tip: sched/core] sched/fair: Clean " tip-bot2 for Vincent Guittot
2019-10-30 14:51   ` [PATCH v4 01/11] sched/fair: clean " Mel Gorman
2019-10-30 16:03     ` Vincent Guittot
2019-10-18 13:26 ` [PATCH v4 02/11] sched/fair: rename sum_nr_running to sum_h_nr_running Vincent Guittot
2019-10-21  9:12   ` [tip: sched/core] sched/fair: Rename sg_lb_stats::sum_nr_running " tip-bot2 for Vincent Guittot
2019-10-30 14:53   ` [PATCH v4 02/11] sched/fair: rename sum_nr_running " Mel Gorman
2019-10-18 13:26 ` [PATCH v4 03/11] sched/fair: remove meaningless imbalance calculation Vincent Guittot
2019-10-21  9:12   ` [tip: sched/core] sched/fair: Remove " tip-bot2 for Vincent Guittot
2019-10-18 13:26 ` [PATCH v4 04/11] sched/fair: rework load_balance Vincent Guittot
2019-10-21  9:12   ` [tip: sched/core] sched/fair: Rework load_balance() tip-bot2 for Vincent Guittot
2019-10-30 15:45   ` [PATCH v4 04/11] sched/fair: rework load_balance Mel Gorman
2019-10-30 16:16     ` Valentin Schneider
2019-10-31  9:09     ` Vincent Guittot
2019-10-31 10:15       ` Mel Gorman
2019-10-31 11:13         ` Vincent Guittot
2019-10-31 11:40           ` Mel Gorman
2019-11-08 16:35             ` Vincent Guittot
2019-11-08 18:37               ` Mel Gorman
2019-11-12 10:58                 ` Vincent Guittot
2019-11-12 15:06                   ` Mel Gorman
2019-11-12 15:40                     ` Vincent Guittot
2019-11-12 17:45                       ` Mel Gorman
2019-11-18 13:50     ` Ingo Molnar
2019-11-18 13:57       ` Vincent Guittot
2019-11-18 14:51       ` Mel Gorman
2019-10-18 13:26 ` [PATCH v4 05/11] sched/fair: use rq->nr_running when balancing load Vincent Guittot
2019-10-21  9:12   ` [tip: sched/core] sched/fair: Use " tip-bot2 for Vincent Guittot
2019-10-30 15:54   ` [PATCH v4 05/11] sched/fair: use " Mel Gorman
2019-10-18 13:26 ` [PATCH v4 06/11] sched/fair: use load instead of runnable load in load_balance Vincent Guittot
2019-10-21  9:12   ` [tip: sched/core] sched/fair: Use load instead of runnable load in load_balance() tip-bot2 for Vincent Guittot
2019-10-30 15:58   ` [PATCH v4 06/11] sched/fair: use load instead of runnable load in load_balance Mel Gorman
2019-10-18 13:26 ` [PATCH v4 07/11] sched/fair: evenly spread tasks when not overloaded Vincent Guittot
2019-10-21  9:12   ` [tip: sched/core] sched/fair: Spread out tasks evenly " tip-bot2 for Vincent Guittot
2019-10-30 16:03   ` [PATCH v4 07/11] sched/fair: evenly spread tasks " Mel Gorman
2019-10-18 13:26 ` Vincent Guittot [this message]
2019-10-21  9:12   ` [tip: sched/core] sched/fair: Use utilization to select misfit task tip-bot2 for Vincent Guittot
2019-10-18 13:26 ` [PATCH v4 09/11] sched/fair: use load instead of runnable load in wakeup path Vincent Guittot
2019-10-21  9:12   ` [tip: sched/core] sched/fair: Use " tip-bot2 for Vincent Guittot
2019-10-18 13:26 ` [PATCH v4 10/11] sched/fair: optimize find_idlest_group Vincent Guittot
2019-10-21  9:12   ` [tip: sched/core] sched/fair: Optimize find_idlest_group() tip-bot2 for Vincent Guittot
2019-10-18 13:26 ` [PATCH v4 11/11] sched/fair: rework find_idlest_group Vincent Guittot
2019-10-21  9:12   ` [tip: sched/core] sched/fair: Rework find_idlest_group() tip-bot2 for Vincent Guittot
2019-10-22 16:46   ` [PATCH] sched/fair: fix rework of find_idlest_group() Vincent Guittot
2019-10-23  7:50     ` Chen, Rong A
2019-10-30 16:07     ` Mel Gorman
2019-11-18 17:42     ` [tip: sched/core] sched/fair: Fix " tip-bot2 for Vincent Guittot
2019-11-22 14:37     ` [PATCH] sched/fair: fix " Valentin Schneider
2019-11-25  9:16       ` Vincent Guittot
2019-11-25 11:03         ` Valentin Schneider
2019-11-20 11:58   ` [PATCH v4 11/11] sched/fair: rework find_idlest_group Qais Yousef
2019-11-20 13:21     ` Vincent Guittot
2019-11-20 16:53       ` Vincent Guittot
2019-11-20 17:34         ` Qais Yousef
2019-11-20 17:43           ` Vincent Guittot
2019-11-20 18:10             ` Qais Yousef
2019-11-20 18:20               ` Vincent Guittot
2019-11-20 18:27                 ` Qais Yousef
2019-11-20 19:28                   ` Vincent Guittot
2019-11-20 19:55                     ` Qais Yousef
2019-11-21 14:58                       ` Qais Yousef
2019-11-22 14:34   ` Valentin Schneider
2019-11-25  9:59     ` Vincent Guittot
2019-11-25 11:13       ` Valentin Schneider
2019-10-21  7:50 ` [PATCH v4 00/10] sched/fair: rework the CFS load balance Ingo Molnar
2019-10-21  8:44   ` Vincent Guittot
2019-10-21 12:56     ` Phil Auld
2019-10-24 12:38     ` Phil Auld
2019-10-24 13:46       ` Phil Auld
2019-10-24 14:59         ` Vincent Guittot
2019-10-25 13:33           ` Phil Auld
2019-10-28 13:03             ` Vincent Guittot
2019-10-30 14:39               ` Phil Auld
2019-10-30 16:24                 ` Dietmar Eggemann
2019-10-30 16:35                   ` Valentin Schneider
2019-10-30 17:19                     ` Phil Auld
2019-10-30 17:25                       ` Valentin Schneider
2019-10-30 17:29                         ` Phil Auld
2019-10-30 17:28                       ` Vincent Guittot
2019-10-30 17:44                         ` Phil Auld
2019-10-30 17:25                 ` Vincent Guittot
2019-10-31 13:57                   ` Phil Auld
2019-10-31 16:41                     ` Vincent Guittot
2019-10-30 16:24   ` Mel Gorman
2019-10-30 16:35     ` Vincent Guittot
2019-11-18 13:15     ` Ingo Molnar
2019-11-25 12:48 ` Valentin Schneider
2020-01-03 16:39   ` Valentin Schneider

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1571405198-27570-9-git-send-email-vincent.guittot@linaro.org \
    --to=vincent.guittot@linaro.org \
    --cc=Morten.Rasmussen@arm.com \
    --cc=dietmar.eggemann@arm.com \
    --cc=hdanton@sina.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=parth@linux.ibm.com \
    --cc=pauld@redhat.com \
    --cc=peterz@infradead.org \
    --cc=quentin.perret@arm.com \
    --cc=riel@surriel.com \
    --cc=srikar@linux.vnet.ibm.com \
    --cc=valentin.schneider@arm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).