From patchwork Wed May 5 10:59:40 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Zijlstra X-Patchwork-Id: 12239757 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8206AC433ED for ; Wed, 5 May 2021 11:18:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 540F9613C7 for ; Wed, 5 May 2021 11:18:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232915AbhEELTh (ORCPT ); Wed, 5 May 2021 07:19:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51490 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232854AbhEELTh (ORCPT ); Wed, 5 May 2021 07:19:37 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C2F02C061761; Wed, 5 May 2021 04:18:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Subject:Cc:To:From:Date:Message-ID: Sender:Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To:References; bh=0MrMsSt2tV5B1WSdY54KIILEtmSIA0/QggdrXISHTE4=; b=MZs32ecLkErof+HJRhHK+/aqxT ABfhxmvOpw0njH5gPfHjW2lHrGvcc3kv+mUEPPbY2F+HheZNlWu0kRIwiBoW7RwYhGmLLpRMXqRzR cPxxG085d3SZd00ECa/kuDGbPSWircI2xECvYqh8NtdO2aQX40TwmNjPE4H++aiIkCjlgPFqn6mPL mqG28eb7eJ7oxu/1aJKVZOfr/h7H1ovEZ4JJbkOtud4KAIlYwkRYKf31mRdcsKgtn7a154ZqFZc4F 9q4ORLsAsLSqDUH8o3IaEGIpXo74LmvZrQsOyBuA41Z8ksDb+mqmCanAtSaTsStcewOYuzt046lLE 0cYcxxCw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1leFXl-0014WF-Hv; Wed, 05 May 2021 11:18:19 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 2B2FE300233; Wed, 5 May 2021 13:18:14 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id DBCEF299E9863; Wed, 5 May 2021 13:18:14 +0200 (CEST) Message-ID: <20210505105940.190490250@infradead.org> User-Agent: quilt/0.66 Date: Wed, 05 May 2021 12:59:40 +0200 From: Peter Zijlstra To: tglx@linutronix.de, mingo@kernel.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, bsingharora@gmail.com, pbonzini@redhat.com, maz@kernel.org Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, peterz@infradead.org, riel@surriel.com, hannes@cmpxchg.org Subject: [PATCH 0/6] sched,delayacct: Some cleanups Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Hi, Due to: https://lkml.kernel.org/r/0000000000001d43ac05c0f5c6a0@google.com and general principle, delayacct really shouldn't be using ktime (pvclock also really shouldn't be doing what it does, but that's another story). This lead me to looking at the SCHED_INFO, SCHEDSTATS, DELAYACCT (and PSI) accounting hell. The rest of the patches are an attempt at simplifying all that a little. All that crud is enabled by default for distros which is leading to a death by a thousand cuts. The last patch is an attempt at default disabling DELAYACCT, because I don't think anybody actually uses that much, but what do I know, there were no ill effects on my testbox. Perhaps we should mirror /proc/sys/kernel/sched_schedstats and provide a delayacct sysctl for runtime frobbing. Reviewed-by: Thomas Gleixner Reviewed-by: Ingo Molnar