From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id CE99E483 for ; Tue, 28 Jul 2015 22:09:19 +0000 (UTC) Received: from seldrel01.sonyericsson.com (seldrel01.sonyericsson.com [37.139.156.2]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 023307C for ; Tue, 28 Jul 2015 22:09:18 +0000 (UTC) Message-ID: <55B7FD82.8010806@sonymobile.com> Date: Tue, 28 Jul 2015 15:09:06 -0700 From: Tim Bird MIME-Version: 1.0 To: Mark Brown , Steven Rostedt References: <20150723105726.GC30929@amd> <20150723121441.GB29747@amd> <20150723084251.54da2be0@gandalf.local.home> <20150723154014.GD11162@sirena.org.uk> In-Reply-To: <20150723154014.GD11162@sirena.org.uk> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Cc: Pavel Machek , "ksummit-discuss@lists.linuxfoundation.org" , "riverful.kim@samsung.com" , "kyungmin.park@samsung.com" , John Stultz , =?windows-1252?Q?=22Andersson=2C_?= =?windows-1252?Q?Bj=F6rn=22?= Subject: Re: [Ksummit-discuss] [CORE TOPIC] Mainline kernel on a cellphone List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 07/23/2015 08:40 AM, Mark Brown wrote: > On Thu, Jul 23, 2015 at 08:42:51AM -0400, Steven Rostedt wrote: > >> Although is this something to be a core topic or a tech topic? Does >> this affect all subsystems, or just a set of drivers? Note, a core >> topic wont get as much time for discussion as a tech topic would. > > It's basically all subsystems that get impacted, at the minute I'd say > it's more a plan of action and process discussion than a technical one > though in the context of KS planning that's quite probably the same > thing. > >> Also, what is expected to be solved at KS? > > Tim Bird (Cced) has been running some sessions at other conferences > scoping the problem and discussing ways to move forward on this, another > similar session might be useful. As Mark says, I've been working on almost exactly this topic for several months now. Last year I conducted a survey investigating obstacles that developers (mostly corporate product developers) have in mainlining. There are lots of non-technical issues that are worth working on (version gap, corporate incentives, training, etc.), but which are outside the scope of the kernel summit. There are also some technical areas where I think coordinated effort might be useful, to identify deficiencies and collaborate on progress. These might be worth discussing at the summit. In March of this year, I analysed code from several shipping phones (representing a number of different SoCs, including both ARM and Intel-architecture CPUs), and found that most products have between 1.2 and 3 million lines of code out-of-tree. We are still in progress of finding patterns of out-of-treeness, to inform decisions about technical projects going forward. There is now a wiki page at: See http://elinux.org/Kernel_areas_of_focus_for_mainlining In particular it has a table showing certain areas that tend to have a lot of out-of-tree code (e.g. most phones have between 80K to 100K of lines of wireless driver support out-of-mainline) IMHO it would be useful to discuss these areas, to see if there are technical reasons for these deficiencies, and work to resolve them. -- Tim