From nobody Wed Feb 11 08:37:20 2026 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C054D7E563 for ; Wed, 4 Sep 2024 17:15:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725470114; cv=none; b=aUqXMSh7HnKbr44JbBoP3aIjzEB3W9msY8pTqvkR/ABoeOisiW4oGqhSsPqKi1+p0aVLXreZNYAlyIAEDJAjhSvyx/bum0IG0ALjI61wqdjk+TeOCfdLclonx7GpkuC3UvZxba0CNALMmUSQrzEanQueFYjoOtw3Ng7w+35rK0g= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725470114; c=relaxed/simple; bh=Wau/q+35GYpxQ+DMRtXpevDS07OwHE6batl31i3kT7s=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lxr0gMKVLLbPaZQtC1+HD7DVJfr9Ai61iPK2wGbkdNoLPqYErBTAcyrQW5CKlm+5Rou5Z8lNm3zKIQ8BO9K7Lqowe0ifukeQzCEqY7Qtup2WPxx2vNEKimhQkkRwTi/T7KfgGpVTUoo1GqTu8oJ+e/gx8WGz3tOAytBRFasTIXE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=Gp3KastY; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Gp3KastY" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1725470111; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=CWMJPGHHsyqwh2jeUcl0baof59j2hw5GpcL0saOPeyM=; b=Gp3KastY4gOjFW9tkUpz47ROIfoROTEmpX+M8FMg5c3rdca25A2v9C/u4OoTte+SEF+dKd YAsELExq35kr78I1umOUM1T9pyaiac/9+5bHvx7SEAL4Dceuw4MUmevqrq1pe79R1Xnx8/ igD38hdXMv4QwmlCp79i1MuTvLJT61I= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-518-lptWHoj9OiO-BejzWC5vgA-1; Wed, 04 Sep 2024 13:15:07 -0400 X-MC-Unique: lptWHoj9OiO-BejzWC5vgA-1 Received: from mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.40]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id B413D1944AA5; Wed, 4 Sep 2024 17:15:05 +0000 (UTC) Received: from llong.com (unknown [10.2.16.172]) by mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 8B58A1955D42; Wed, 4 Sep 2024 17:15:03 +0000 (UTC) From: Waiman Long To: Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , Frederic Weisbecker Cc: linux-kernel@vger.kernel.org, Phil Auld , Waiman Long Subject: [PATCH v2 1/2] sched/core: Remove HK_TYPE_SCHED Date: Wed, 4 Sep 2024 13:14:40 -0400 Message-ID: <20240904171441.1048072-2-longman@redhat.com> In-Reply-To: <20240904171441.1048072-1-longman@redhat.com> References: <20240904171441.1048072-1-longman@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.0 on 10.30.177.40 Content-Type: text/plain; charset="utf-8" The HK_TYPE_SCHED housekeeping type is defined but not set anywhere. So any code that try to use HK_TYPE_SCHED are essentially dead code. So remove HK_TYPE_SCHED and any code that use it. Signed-off-by: Waiman Long --- include/linux/sched/isolation.h | 1 - kernel/sched/fair.c | 14 -------------- kernel/sched/isolation.c | 1 - 3 files changed, 16 deletions(-) diff --git a/include/linux/sched/isolation.h b/include/linux/sched/isolatio= n.h index 2b461129d1fa..499d5e480882 100644 --- a/include/linux/sched/isolation.h +++ b/include/linux/sched/isolation.h @@ -10,7 +10,6 @@ enum hk_type { HK_TYPE_TIMER, HK_TYPE_RCU, HK_TYPE_MISC, - HK_TYPE_SCHED, HK_TYPE_TICK, HK_TYPE_DOMAIN, HK_TYPE_WQ, diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 9057584ec06d..ac5ed846fb55 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -11840,9 +11840,6 @@ static inline int on_null_domain(struct rq *rq) * - When one of the busy CPUs notices that there may be an idle rebalanci= ng * needed, they will kick the idle load balancer, which then does idle * load balancing for all the idle CPUs. - * - * - HK_TYPE_MISC CPUs are used for this task, because HK_TYPE_SCHED is no= t set - * anywhere yet. */ static inline int find_new_ilb(void) { @@ -12087,10 +12084,6 @@ void nohz_balance_enter_idle(int cpu) if (!cpu_active(cpu)) return; =20 - /* Spare idle load balancing on CPUs that don't want to be disturbed: */ - if (!housekeeping_cpu(cpu, HK_TYPE_SCHED)) - return; - /* * Can be set safely without rq->lock held * If a clear happens, it will have evaluated last additions because @@ -12310,13 +12303,6 @@ static void nohz_newidle_balance(struct rq *this_r= q) { int this_cpu =3D this_rq->cpu; =20 - /* - * This CPU doesn't want to be disturbed by scheduler - * housekeeping - */ - if (!housekeeping_cpu(this_cpu, HK_TYPE_SCHED)) - return; - /* Will wake up very soon. No time for doing anything else*/ if (this_rq->avg_idle < sysctl_sched_migration_cost) return; diff --git a/kernel/sched/isolation.c b/kernel/sched/isolation.c index 5891e715f00d..5345e11f3d44 100644 --- a/kernel/sched/isolation.c +++ b/kernel/sched/isolation.c @@ -12,7 +12,6 @@ enum hk_flags { HK_FLAG_TIMER =3D BIT(HK_TYPE_TIMER), HK_FLAG_RCU =3D BIT(HK_TYPE_RCU), HK_FLAG_MISC =3D BIT(HK_TYPE_MISC), - HK_FLAG_SCHED =3D BIT(HK_TYPE_SCHED), HK_FLAG_TICK =3D BIT(HK_TYPE_TICK), HK_FLAG_DOMAIN =3D BIT(HK_TYPE_DOMAIN), HK_FLAG_WQ =3D BIT(HK_TYPE_WQ), --=20 2.43.5