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bh=4nTIOgTO+qYjQsnQ4NpqRvMg/QW7WYohWkM8lwQarB0=; b=Unnl66OMjqc2CluhtNOzSCA+iXqAJ0/9HnsDB3GZv2CN8UTski68PGh5+GrvTdnoRBlI9No1Er48dfGVr9safTvk1Kb/fMd/szP8dfZXvVAK7G5K7j8wfI66ItsHOObpxA5Y8krBG+9amG6Uk2sY897K6ek5DXGpFkuae7unQbo= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=os.amperecomputing.com; Received: from MW4PR01MB6436.prod.exchangelabs.com (2603:10b6:303:64::21) by DS1PR01MB9086.prod.exchangelabs.com (2603:10b6:8:221::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8207.12; Wed, 27 Nov 2024 05:57:26 +0000 Received: from MW4PR01MB6436.prod.exchangelabs.com ([fe80::77c9:9e36:e28e:7970]) by MW4PR01MB6436.prod.exchangelabs.com ([fe80::77c9:9e36:e28e:7970%4]) with mapi id 15.20.8207.010; Wed, 27 Nov 2024 05:57:26 +0000 From: Adam Li To: peterz@infradead.org, mingo@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org Cc: dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, linux-kernel@vger.kernel.org, patches@amperecomputing.com, cl@linux.com, christian.loehle@arm.com, vineethr@linux.ibm.com, Adam Li Subject: [PATCH v2 3/3] sched/fair: Update comments regarding last and skip buddy Date: Wed, 27 Nov 2024 05:56:10 +0000 Message-Id: <20241127055610.7076-4-adamli@os.amperecomputing.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20241127055610.7076-1-adamli@os.amperecomputing.com> References: <20241127055610.7076-1-adamli@os.amperecomputing.com> Content-Transfer-Encoding: quoted-printable X-ClientProxiedBy: SGBP274CA0018.SGPP274.PROD.OUTLOOK.COM (2603:1096:4:b0::30) To SJ0PR01MB6445.prod.exchangelabs.com (2603:10b6:a03:2a1::14) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: MW4PR01MB6436:EE_|DS1PR01MB9086:EE_ X-MS-Office365-Filtering-Correlation-Id: 7e50385f-3cfa-4b83-2d7c-08dd0ea85538 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|1800799024|52116014|7416014|376014|38350700014; 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charset="utf-8" Commit 5e963f2bd465 ("sched/fair: Commit to EEVDF") removed the "last" and "skip" buddy. Update comments in pick_next_entity(). Signed-off-by: Adam Li Reviewed-by: Madadi Vineeth Reddy Reviewed-by: Adam Li --- kernel/sched/fair.c | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index d5a3b5589e4e..259c56dcdff6 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5602,17 +5602,11 @@ set_next_entity(struct cfs_rq *cfs_rq, struct sched= _entity *se) =20 static int dequeue_entities(struct rq *rq, struct sched_entity *se, int fl= ags); =20 -/* - * Pick the next process, keeping these things in mind, in this order: - * 1) keep things fair between processes/task groups - * 2) pick the "next" process, since someone really wants that to run - * 3) pick the "last" process, for cache locality - * 4) do not run the "skip" process, if something else is available - */ static struct sched_entity * pick_next_entity(struct rq *rq, struct cfs_rq *cfs_rq) { /* + * Pick the "next" buddy, since someone really wants that to run. * Enabling NEXT_BUDDY will affect latency but not fairness. */ if (sched_feat(NEXT_BUDDY) && --=20 2.25.1