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 7F092C43334 for ; Wed, 22 Jun 2022 17:39:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376483AbiFVRjg (ORCPT ); Wed, 22 Jun 2022 13:39:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45800 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359087AbiFVRjd (ORCPT ); Wed, 22 Jun 2022 13:39:33 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BF08F2CE1A; Wed, 22 Jun 2022 10:39:32 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 7B1251F38A; Wed, 22 Jun 2022 17:39:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1655919571; h=from:from:reply-to: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=qjLsn3chRmVR7wBslFm7Nmwci+bvj1b1+qTpUK32rXQ=; b=iGD8LGlhBV+ijnTy+c24IKvp3gS6t3Xd7fZf0W5mhS4jcdaQdBdVobDGrLTSUQYAXoEATz JokCZyEMcnVxZEGqwjaMlMEyZdB0kDdegEDn9d5unKiSxSMx7nn9t4BUaYxsUPslHkd98r aF5iZpfXyd/FBxVY1CTQo6j408qFIqM= Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 22E08134A9; Wed, 22 Jun 2022 17:39:31 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id 571xB9NTs2JaLwAAMHmgww (envelope-from ); Wed, 22 Jun 2022 17:39:31 +0000 Date: Wed, 22 Jun 2022 19:39:29 +0200 From: Michal =?iso-8859-1?Q?Koutn=FD?= To: Chengming Zhou Cc: rdunlap@infradead.org, mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, tj@kernel.org, lizefan.x@bytedance.com, hannes@cmpxchg.org, corbet@lwn.net, cgroups@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] sched: RT bandwidth interface for cgroup unified hierarchy Message-ID: <20220622173929.GA669@blackbody.suse.cz> References: <20220622015557.7497-1-zhouchengming@bytedance.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220622015557.7497-1-zhouchengming@bytedance.com> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Chengming. On Wed, Jun 22, 2022 at 09:55:57AM +0800, Chengming Zhou wrote: > We need to run RT threads in cgroup unified hierarchy, but we can't > since the default rt_bandwidth.rt_runtime of non-root task_group is 0 > and we haven't interface to update it. Do you really want to make use of group RT schedulling (CONFIG_RT_GROUP_SCHED) or just be able to run RT threads in the unified hieararchy with cpu controller enabled? Those are two different use cases, the former is more complex and it's a reason why v2 doesn't expose the RT attributes (yet). The latter is typically achieved by unsetting CONFIG_RT_GROUP_SCHED (and relying on the global rt_runtime limit). Thanks, Michal