From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760272AbdCVOwu (ORCPT ); Wed, 22 Mar 2017 10:52:50 -0400 Received: from bombadil.infradead.org ([65.50.211.133]:51136 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759285AbdCVOwn (ORCPT ); Wed, 22 Mar 2017 10:52:43 -0400 Date: Wed, 22 Mar 2017 15:52:25 +0100 From: Peter Zijlstra To: Tejun Heo Cc: lizefan@huawei.com, hannes@cmpxchg.org, mingo@redhat.com, pjt@google.com, luto@amacapital.net, efault@gmx.de, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com, lvenanci@redhat.com, Linus Torvalds , Andrew Morton Subject: Re: [PATCHSET for-4.11] cgroup: implement cgroup v2 thread mode Message-ID: <20170322145225.nsmnvknla752e6yx@hirez.programming.kicks-ass.net> References: <20170203205955.GA9886@mtj.duckdns.org> <20170206124943.GJ6515@twins.programming.kicks-ass.net> <20170208230819.GD25826@htj.duckdns.org> <20170209102909.GC6515@twins.programming.kicks-ass.net> <20170210154508.GA16097@mtj.duckdns.org> <20170210175145.GJ6515@twins.programming.kicks-ass.net> <20170212050544.GJ29323@mtj.duckdns.org> <20170214103541.GS6515@twins.programming.kicks-ass.net> <20170313200544.GE15709@htj.duckdns.org> <20170321123958.af7mcvcovexxzahu@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170321123958.af7mcvcovexxzahu@hirez.programming.kicks-ass.net> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 21, 2017 at 01:39:58PM +0100, Peter Zijlstra wrote: > > And yes, having to consider views is new and a direct consequence of > this new optional feature. But I don't see how its a problem. > So aside from having (RO) links in thread groups for system controllers, we could also have a ${controller}_parent link back to whatever group is the actual parent for that specific controller's view. So then your B's memcg_parent would point to A, not T. But I feel this is all superfluous window dressing; but if you want to clarify the filesystem interface, this could be something to consider. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [PATCHSET for-4.11] cgroup: implement cgroup v2 thread mode Date: Wed, 22 Mar 2017 15:52:25 +0100 Message-ID: <20170322145225.nsmnvknla752e6yx@hirez.programming.kicks-ass.net> References: <20170203205955.GA9886@mtj.duckdns.org> <20170206124943.GJ6515@twins.programming.kicks-ass.net> <20170208230819.GD25826@htj.duckdns.org> <20170209102909.GC6515@twins.programming.kicks-ass.net> <20170210154508.GA16097@mtj.duckdns.org> <20170210175145.GJ6515@twins.programming.kicks-ass.net> <20170212050544.GJ29323@mtj.duckdns.org> <20170214103541.GS6515@twins.programming.kicks-ass.net> <20170313200544.GE15709@htj.duckdns.org> <20170321123958.af7mcvcovexxzahu@hirez.programming.kicks-ass.net> Mime-Version: 1.0 Return-path: 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:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=ZCBcZdVVTJ/A2/XULMPCAu2Tje/JWuS2oUSEMNMtwr0=; b=kgZr9qr5NHZB6bzGkZEOcmJhW Pu1nwljOSd9MC5dgcroDAkuYEBW9ckmRgQqQiM50WmDGKin5pJQbWMlKhjsf+tSzBjYe85D0VseJY z7qTnd7TADRUgnM8UdIUdfM1ncfd7mNb77HACRT41aMgZhL4UliYSd9M8ihdr9al8bKoq4G28dlQA NOplAwpS7Mom8enUcJbKPmyBGGiAUORuysAluMxGkVB4+6+x2X6PkWOA/bFgswQ5A8+R8d+hDYSi+ p3s09eFfDE8LJ9rKr2p0yAhs8maBrdB0ryiSswzDu7Ql8j6Ily+httIbWqaUiCUkOQ6ZAejaTw+2m Content-Disposition: inline In-Reply-To: <20170321123958.af7mcvcovexxzahu-Nxj+rRp3nVydTX5a5knrm8zTDFooKrT+cvkQGrU6aU0@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Tejun Heo Cc: lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org, mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, pjt-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, luto-kltTT9wpgjJwATOyAt5JVQ@public.gmane.org, efault-Mmb7MZpHnFY@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, kernel-team-b10kYP2dOMg@public.gmane.org, lvenanci-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Linus Torvalds , Andrew Morton On Tue, Mar 21, 2017 at 01:39:58PM +0100, Peter Zijlstra wrote: > > And yes, having to consider views is new and a direct consequence of > this new optional feature. But I don't see how its a problem. > So aside from having (RO) links in thread groups for system controllers, we could also have a ${controller}_parent link back to whatever group is the actual parent for that specific controller's view. So then your B's memcg_parent would point to A, not T. But I feel this is all superfluous window dressing; but if you want to clarify the filesystem interface, this could be something to consider.