From nobody Sun Apr 12 02:48:35 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F3A4BC00140 for ; Tue, 2 Aug 2022 11:03:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236751AbiHBLDX (ORCPT ); Tue, 2 Aug 2022 07:03:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39480 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236728AbiHBLDT (ORCPT ); Tue, 2 Aug 2022 07:03:19 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 44E044F656; Tue, 2 Aug 2022 04:03:18 -0700 (PDT) Date: Tue, 02 Aug 2022 11:03:15 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1659438196; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=vXNVaiJ88X6B9vRwZaMF5TykDK+rWRqoy9ICuls3qBo=; b=aULBAbB1vXGpHrNY36ZwgNYXJAqTJBVqQjxAsiFuvu716JerHD6DgOlm4cNfUF+3SRHuVs SDcWZYKyV3kxPdIK9xrAT9ds0JfrOA6SP02KXBBxGc0SuIdm9L9ObDJJ8SwmU/26M6vnKJ NbgvhJpQfh5IZRnCZxcOJaO4NfP6BVyHNZpvLZXJMis/ybgHUN0LRT20TXRQP4k/WjYPbi EV3IxudluJtebHD4bgEbVgmPzlAqv+LfO810FkICiWKdTMkT1q1Ir0+Vd0HS/NKl7k019H lqVrsPxPQgIn+207DN6UQvoOt1PMBSAjcAes4kDeCOKQ1Iiis5dwu2i8Tt3eUA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1659438196; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=vXNVaiJ88X6B9vRwZaMF5TykDK+rWRqoy9ICuls3qBo=; b=msNAzvOUUHYeAdsyj+uVojfRIg+tYP3uaeXB4arIHLRLT9tlOCFa9s4RyAwSzi3CpWqfk/ RLCI/ZkvrPOQ44Bg== From: "tip-bot2 for Dietmar Eggemann" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: sched/core] sched/deadline: Use sched_dl_entity's dl_density in dl_task_fits_capacity() Cc: Dietmar Eggemann , Ingo Molnar , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20220729111305.1275158-4-dietmar.eggemann@arm.com> References: <20220729111305.1275158-4-dietmar.eggemann@arm.com> MIME-Version: 1.0 Message-ID: <165943819521.15455.1190018314589445418.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the sched/core branch of tip: Commit-ID: b3f53daacc74c0ca0922e14a8cb793cb2db4c6d1 Gitweb: https://git.kernel.org/tip/b3f53daacc74c0ca0922e14a8cb793cb2= db4c6d1 Author: Dietmar Eggemann AuthorDate: Fri, 29 Jul 2022 13:13:05 +02:00 Committer: Ingo Molnar CommitterDate: Tue, 02 Aug 2022 12:32:46 +02:00 sched/deadline: Use sched_dl_entity's dl_density in dl_task_fits_capacity() Save a multiplication in dl_task_fits_capacity() by using already maintained per-sched_dl_entity (i.e. per-task) `dl_runtime/dl_deadline` (dl_density). cap_scale(dl_deadline, cap) >=3D dl_runtime dl_deadline * cap >> SCHED_CAPACITY_SHIFT >=3D dl_runtime cap >=3D dl_runtime << SCHED_CAPACITY_SHIFT / dl_deadline cap >=3D (dl_runtime << BW_SHIFT / dl_deadline) >> BW_SHIFT - SCHED_CAPACITY_SHIFT cap >=3D dl_density >> BW_SHIFT - SCHED_CAPACITY_SHIFT __sched_setscheduler()->__checkparam_dl() ensures that the 2 corner cases (if conditions) `runtime =3D=3D RUNTIME_INF (-1)` and `period =3D=3D = 0` of to_ratio(deadline, runtime) are not met when setting dl_density in __sched_setscheduler()-> __setscheduler_params()->__setparam_dl(). Signed-off-by: Dietmar Eggemann Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20220729111305.1275158-4-dietmar.eggemann@a= rm.com --- kernel/sched/sched.h | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-) diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 86fc360..3ccd35c 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -320,21 +320,6 @@ struct dl_bw { u64 total_bw; }; =20 -/* - * Verify the fitness of task @p to run on @cpu taking into account the - * CPU original capacity and the runtime/deadline ratio of the task. - * - * The function will return true if the CPU original capacity of the - * @cpu scaled by SCHED_CAPACITY_SCALE >=3D runtime/deadline ratio of the - * task and false otherwise. - */ -static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu) -{ - unsigned long cap =3D arch_scale_cpu_capacity(cpu); - - return cap_scale(p->dl.dl_deadline, cap) >=3D p->dl.dl_runtime; -} - extern void init_dl_bw(struct dl_bw *dl_b); extern int sched_dl_global_validate(void); extern void sched_dl_do_global(void); @@ -2899,6 +2884,21 @@ unsigned long effective_cpu_util(int cpu, unsigned l= ong util_cfs, enum cpu_util_type type, struct task_struct *p); =20 +/* + * Verify the fitness of task @p to run on @cpu taking into account the + * CPU original capacity and the runtime/deadline ratio of the task. + * + * The function will return true if the original capacity of @cpu is + * greater than or equal to task's deadline density right shifted by + * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise. + */ +static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu) +{ + unsigned long cap =3D arch_scale_cpu_capacity(cpu); + + return cap >=3D p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT); +} + static inline unsigned long cpu_bw_dl(struct rq *rq) { return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;