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 X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AFBBFC3276C for ; Thu, 2 Jan 2020 23:50:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7DE9622314 for ; Thu, 2 Jan 2020 23:50:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Hp+747Sd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726927AbgABXuE (ORCPT ); Thu, 2 Jan 2020 18:50:04 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:50276 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725890AbgABXuD (ORCPT ); Thu, 2 Jan 2020 18:50:03 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1578009002; h=from:from:reply-to:subject:subject: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=Xcf0YP80Mto0kO83rbF2DzFh7h3JXBfJISRV5C5tT8E=; b=Hp+747SdWGnwd808hqScoSDWanDwrd6CZbgLJiSblGoDH3gCjuMaWMOng9M7+GRm2k1Vv2 H0CcQF6F5wz/wTEyhphH/5UYsfrgS+cYL20DzRGz04xxqjLopWK+cfZVz+Je3cR55fiRJF ZGBogncoekp1qR0Oh2wzHOCMN3tAOC4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-121-_8idDAM8OMyvONYDDL_zvA-1; Thu, 02 Jan 2020 18:49:57 -0500 X-MC-Unique: _8idDAM8OMyvONYDDL_zvA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D5FFD180124F; Thu, 2 Jan 2020 23:49:55 +0000 (UTC) Received: from krava (ovpn-204-83.brq.redhat.com [10.40.204.83]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C734C7A4F1; Thu, 2 Jan 2020 23:49:53 +0000 (UTC) Date: Fri, 3 Jan 2020 00:49:50 +0100 From: Jiri Olsa To: Steven Rostedt Cc: Sudip Mukherjee , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Masami Hiramatsu , Linux Trace Devel , LKML , Linus Torvalds Subject: Re: [RFC] tools lib traceevent: How to do library versioning being in the Linux kernel source? Message-ID: <20200102234950.GA14768@krava> References: <20200102122004.216c85da@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200102122004.216c85da@gandalf.local.home> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Sender: linux-trace-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org On Thu, Jan 02, 2020 at 12:20:04PM -0500, Steven Rostedt wrote: > First, I hope everyone had a Happy New Year! heya, Happy New Year! ;-) > > Next, Sudip has been working to get the libtraceevent library into > Debian. As this has been happening, I've been working at how to get all > the projects that use this, to use the library installed on the system > if it does exist. I'm hoping that once it's in Debian, the other > distros will follow suit. > > Currently, the home of libtraceevent lives in the Linux kernel source > tree under tools/lib/traceevent. This was because perf uses it to parse > the events, and it seemed logical (at the time) to use this location as > the main source tree for the distributions. > > The problem I'm now having is that I'm looking at fixing and updating > some of the code in this library, and since library versioning is > critical for applications that depend on it, we need to have a way to > update the versions, and this does not correspond with the Linux > versions. > > For example, we currently have: > > libtraceevent.so.1.1.0 > > If I make some bug fixes, I probably want to change it to: > > libtraceevent.so.1.1.1 or libtraceevent.so.1.2.0 > > But if I change the API, which I plan on doing soon, I would probably > need to update the major version. > > libtraceevent.so.2.0.0 > > The thing is, we shouldn't be making these changes for every update > that we send to the main kernel. I would like to have a minimum of tags > to state what the version should be, and perhaps even branches for > working on a development version. > > This is a problem with living in the Linux source tree as tags and > branches in Linus's tree are for only the Linux kernel source itself. > This may work fine for perf, as it's not a library and there's not > tools depending on the version of it. But it is a problem when it comes > to shared libraries. > > Should we move libtraceevent into a stand alone git repo (on > kernel.org), that can have tags and branches specifically for it? We > can keep a copy in the Linux source tree for perf to use till it so libbpf 'moved' for this reason to github repo, but keeping the kernel as the true/first source, and updating github repo when release is ready libbpf github repo is then source for fedora (and others) package > becomes something that is reliably in all distributions. It's not like > perf doesn't depend on other libraries today anyway. yep, we already have a way to link libbpf dynamicaly from package, will work the same for libtraceevent jirka