From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH REPOST RFC cgroup/for-3.7] cgroup: mark subsystems with broken hierarchy support and whine if cgroups are nested for them Date: Thu, 13 Sep 2012 10:18:32 -0700 Message-ID: <20120913171832.GY7677@google.com> References: <20120910223125.GC7677@google.com> <20120910223355.GD7677@google.com> <20120911100433.GC8058@dhcp22.suse.cz> <5050568B.9090601@parallels.com> <20120912154907.GW21579@dhcp22.suse.cz> <20120912171120.GP7677@google.com> <20120913121438.GC8055@dhcp22.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20120913121438.GC8055-2MMpYkNvuYDjFM9bn6wA6Q@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Michal Hocko Cc: Neil Horman , "Serge E. Hallyn" , containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Paul Mackerras , "Aneesh Kumar K.V" , Arnaldo Carvalho de Melo , Johannes Weiner , Thomas Graf , cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Paul Turner , Ingo Molnar , Vivek Goyal List-Id: containers.vger.kernel.org Hello, Michal. On Thu, Sep 13, 2012 at 02:14:38PM +0200, Michal Hocko wrote: > I would like to see use_hierarchy go away. The only concern I have is > to warn only if somebody is doing something wrong (aka flat > hierarchies). Or better put it this way. Do not warn in cases which do > not change if use_hierarchy is gone or default changes to 1. > An example: > root (use_hierarchy=0) > | \ > | A (use_hierarchy=0) > | > B (use_hierarachy=1) > |\ > C D > > is a perfectly sane configuration and I do not see any reason to fill > logs with some scary warnings when A is created. There will be no > semantical change in this setup When use_hierchy is gone. > > So the only thing I am proposing here is to warn only if something > should be fixed in the configuration in order to be prepared for fully > hierarchical (and that is a second level of children from root with > use_hierachy==0). > > Does it make more sense now? Ah, okay, so what you're saying is that we shouldn't warn if 0 .use_hierarchys don't make any behavior difference from when they're all 1, right? If so, I have no objection. Will incorporate your updated version. Thanks. -- tejun