Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755349AbaJNRpn (ORCPT ); Tue, 14 Oct 2014 13:45:43 -0400 Received: from mx1.redhat.com ([209.132.183.28]:62676 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753866AbaJNRpl (ORCPT ); Tue, 14 Oct 2014 13:45:41 -0400 Date: Tue, 14 Oct 2014 19:42:29 +0200 From: Oleg Nesterov To: "Chen, Hanxiao" Cc: "containers@lists.linux-foundation.org" , "linux-kernel@vger.kernel.org" , Serge Hallyn , "Eric W. Biederman" , David Howells , Richard Weinberger , Pavel Emelyanov , Vasiliy Kulikov , Mateusz Guzik Subject: Re: [PATCHv4] procfs: show hierarchy of pid namespace Message-ID: <20141014174229.GA31533@redhat.com> References: <1412762198-21825-1-git-send-email-chenhanxiao@cn.fujitsu.com> <20141008151328.GB4835@redhat.com> <5871495633F38949900D2BF2DC04883E5E1649@G08CNEXMBPEKD02.g08.fujitsu.local> <20141009213414.GA10705@redhat.com> <5871495633F38949900D2BF2DC04883E5E864C@G08CNEXMBPEKD02.g08.fujitsu.local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5871495633F38949900D2BF2DC04883E5E864C@G08CNEXMBPEKD02.g08.fujitsu.local> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/13, Chen, Hanxiao wrote: > > > At the same time, for_each_process() in the global namespace can be > > faster if there are a lot of sub-threads. > > > > > Perhaps that's not a good way. > > > > OK, I won't insist. > > > > although it would be nice to know why do you think this is bad. > > > I worried about it may slower in global namespace. > But it will provide a great convenient way when query pid hierarchy > when not in init_pid_ns. Yes, it is not clear what is actually better, so ... > I'll post a new patch using find_ge_pid + get_pid Only if you think this makes more sense. I do not have a strong opinion. And we can change the implementation at any time. The real problem is the API this patch adds. I leave this to you and other reviewers who understand the problem space better ;) Just I think that the changelog could say a bit more, to explain why do we need this patch. IOW, explain the problem and how/why this patch helps. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/