From mboxrd@z Thu Jan 1 00:00:00 1970 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 1009CC001DE for ; Mon, 31 Jul 2023 16:40:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233343AbjGaQkh (ORCPT ); Mon, 31 Jul 2023 12:40:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39384 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231325AbjGaQkQ (ORCPT ); Mon, 31 Jul 2023 12:40:16 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D2DC9FA for ; Mon, 31 Jul 2023 09:38:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1690821532; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=xbAhBay2kREVBvFLT0nhF2c7lc1w13NfYps20V2UYsQ=; b=BUbFC1eh/W5Or0GvzwQIel5IKsFYfhoUKtb3MqAinz9/8izFxPDxNbMIMBvDJXEio5WX6/ N9dlAbGvOBxVlWRCtEa4Cz/qPveQfbPxnm6fuukV3s6Nf6KDYV3L5zTdughsHuOM/pzcrP 3N/yB0SKkA8DPQ5H+nn5w6nOvZnEOMM= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-386-4xPo1E-QNDuPYN0uJzETiQ-1; Mon, 31 Jul 2023 12:38:47 -0400 X-MC-Unique: 4xPo1E-QNDuPYN0uJzETiQ-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id B1BFF8631DF; Mon, 31 Jul 2023 16:38:38 +0000 (UTC) Received: from lorien.usersys.redhat.com (unknown [10.22.33.53]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 8B736F784C; Mon, 31 Jul 2023 16:38:37 +0000 (UTC) Date: Mon, 31 Jul 2023 12:38:37 -0400 From: Phil Auld To: linux-kernel@vger.kernel.org Cc: Juri Lelli , Ingo Molnar , Daniel Bristot de Oliveira , Peter Zijlstra , Vincent Guittot , Dietmar Eggemann , Valentin Schneider , Ben Segall , Steven Rostedt , Mel Gorman , Frederic Weisbecker , Tejun Heo Subject: Re: [PATCH v6 0/2] Fix nohz_full vs cfs bandwidth Message-ID: <20230731163837.GD232229@lorien.usersys.redhat.com> References: <20230712133357.381137-1-pauld@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230712133357.381137-1-pauld@redhat.com> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Peter, On Wed, Jul 12, 2023 at 09:33:55AM -0400 Phil Auld wrote: > This is v6 of patch 2/2 which is adding code to prevent > the tick from being stopped when the single running task > has bandwidth limits. Discussions had led to the idea of > adding a bit to task_struct to help make this decision. > > There was some complexity with doing it in the task which > is avoided by using something in the cfs_rq. Looking > into that lead me to the hierarchical_quota field in the > cfs_bandwith struct. We spend a good deal of effort > updating (or trying to, see patch 1/2) that value for > the whole task_group tree when a quota is set/changed. > > This new version first fixes that value to be meaningful > for cgroupv2 and then leverages it to make the decisions > about blocking the tick_stop. > > Phil Auld (2): > sched, cgroup: Restore meaning to hierarchical_quota > Sched/fair: Block nohz tick_stop when cfs bandwidth in use > > kernel/sched/core.c | 23 ++++++++++++++--- > kernel/sched/fair.c | 56 ++++++++++++++++++++++++++++++++++++++--- > kernel/sched/features.h | 2 ++ > kernel/sched/sched.h | 3 ++- > 4 files changed, 76 insertions(+), 8 deletions(-) > > -- > 2.31.1 > Ping :) Any thoughts on these now? Cheers, Phil --