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 X-Spam-Level: X-Spam-Status: No, score=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 11B04C433E0 for ; Tue, 16 Jun 2020 14:02:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E310B2071A for ; Tue, 16 Jun 2020 14:02:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Xums47GE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729278AbgFPOC0 (ORCPT ); Tue, 16 Jun 2020 10:02:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58474 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728908AbgFPOCZ (ORCPT ); Tue, 16 Jun 2020 10:02:25 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7D8B1C061573 for ; Tue, 16 Jun 2020 07:02:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=qo9CnAT+aab0Ut3f7Yuy5n9QdYXS6e410dJb6BVWkRI=; b=Xums47GEWXlRQz7J1HKYxW9gMr JD0TMHDcMhQ8xkqodcrWJFLIQd5swU5qrm/olpW54z3c3jZXeCzb03CYU1OzCW/gPla8Dui8ZQxLd n3flGqm0V+23+DraWxkS6YK/kfUgiJ+BHszJqzJK/lSlL7JvVGprakhRvXTvUA31LaUcBExJR1lA6 4gqKweGxBGnoey+ksrWp0GifwLUzSYDUTaddEMsOb9l2HvPjk6UubqlgBJc73xKbG694LiWav9uHY c/2Eq9hTzgS9T2eGm5ztDHu6jRtBrpOvFB6P52AHlZOw24SwWiw+bXPSGI0L7rBTq4d/CaktbIjRN UUMHW0kQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jlCA4-0003JY-UF; Tue, 16 Jun 2020 14:02:01 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id E110630018A; Tue, 16 Jun 2020 16:01:58 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id CD7F22038E4EB; Tue, 16 Jun 2020 16:01:58 +0200 (CEST) Date: Tue, 16 Jun 2020 16:01:58 +0200 From: Peter Zijlstra To: Steven Rostedt Cc: Lichao Liu , mingo@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, bsegall@google.com, mgorman@suse.de, linux-kernel@vger.kernel.org Subject: Re: [PATCH] sched/rt: Don't active rt throtting when no running cfs task Message-ID: <20200616140158.GY2531@hirez.programming.kicks-ass.net> References: <20200616123729.153430-1-liulichao@loongson.cn> <20200616095027.1a2048d0@oasis.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200616095027.1a2048d0@oasis.local.home> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 16, 2020 at 09:50:27AM -0400, Steven Rostedt wrote: > On Tue, 16 Jun 2020 20:37:29 +0800 > Lichao Liu wrote: > > > Active rt throtting will dequeue rt_rq from rq at least 50ms, > > When there is no running cfs task, do we still active it? > > > > This is something I would like to have. > > Peter, what's your thought on this? I'd love to just delete all of this.. that said, I'm not sure this change makes sense, because it doesn't deal sanely with the case where the task will appear right after we did this. The right thing to do is that fair deadline server thing.