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=-0.8 required=3.0 tests=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 6E306C432C0 for ; Tue, 3 Dec 2019 05:38:28 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 233A8206DF for ; Tue, 3 Dec 2019 05:38:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b="d3l8hsvC" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 233A8206DF Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=efficios.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id B124A6B02A9; Tue, 3 Dec 2019 00:38:27 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id AC16C6B02AA; Tue, 3 Dec 2019 00:38:27 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 988AB6B02AB; Tue, 3 Dec 2019 00:38:27 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0096.hostedemail.com [216.40.44.96]) by kanga.kvack.org (Postfix) with ESMTP id 80E706B02A9 for ; Tue, 3 Dec 2019 00:38:27 -0500 (EST) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id 3B61882499A8 for ; Tue, 3 Dec 2019 05:38:27 +0000 (UTC) X-FDA: 76222725054.28.field27_49bad2fe4775e X-HE-Tag: field27_49bad2fe4775e X-Filterd-Recvd-Size: 6065 Received: from mail.efficios.com (mail.efficios.com [167.114.142.138]) by imf02.hostedemail.com (Postfix) with ESMTP for ; Tue, 3 Dec 2019 05:38:26 +0000 (UTC) Received: from localhost (ip6-localhost [IPv6:::1]) by mail.efficios.com (Postfix) with ESMTP id C21CC3474BB; Tue, 3 Dec 2019 00:38:25 -0500 (EST) Received: from mail.efficios.com ([IPv6:::1]) by localhost (mail02.efficios.com [IPv6:::1]) (amavisd-new, port 10032) with ESMTP id To9BgrUq7WIe; Tue, 3 Dec 2019 00:38:25 -0500 (EST) Received: from localhost (ip6-localhost [IPv6:::1]) by mail.efficios.com (Postfix) with ESMTP id 467883474B6; Tue, 3 Dec 2019 00:38:25 -0500 (EST) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com 467883474B6 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=efficios.com; s=default; t=1575351505; bh=5JbB2D4AdM1IiZSBsUN1JC1Quy83U/cq0OLvcNzug/0=; h=Date:From:To:Message-ID:MIME-Version; b=d3l8hsvCtQpRzAK20WX+6XUrYXqhGXSfpFjmaqlnpfavOJU1lmX1hTel6I+jTOvl0 49w4IpQsVihcqBonO6znu+ZpgYUjl3rt8M4wpWJ3jbyGYJefM1FNolVRPOpjWy/T0m r6vrAq9LD+NPm8vsF6OxV1furgV2qg9QqkGBLM/wIaYoEeUN1oiSadWW1yPMSsK/Xs SQT7VZrKpteNsfiTYcSADUWKV35eGqxCp1sRk11OrU6dHQz3MT3LnV17o4l42za5sq xUld1FyLrGrz+bpsntKSuvFt1fQDchQUwqup+j08aQK2hdYGH89IJhlfBmt7RvqKtQ TnysbaHU0tSgg== X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([IPv6:::1]) by localhost (mail02.efficios.com [IPv6:::1]) (amavisd-new, port 10026) with ESMTP id FhBsw7Cugzpv; Tue, 3 Dec 2019 00:38:25 -0500 (EST) Received: from mail02.efficios.com (mail02.efficios.com [167.114.142.138]) by mail.efficios.com (Postfix) with ESMTP id 2596E347496; Tue, 3 Dec 2019 00:38:25 -0500 (EST) Date: Tue, 3 Dec 2019 00:38:24 -0500 (EST) From: Mathieu Desnoyers To: Primiano Tucci Cc: rostedt , "Joel Fernandes, Google" , Andrew Morton , aneesh kumar , Carmen Jackson , Dan Williams , Daniel Colascione , jglisse@redhat.com, linux-mm , Mayank Gupta , Michal Hocko , Minchan Kim , mm-commits@vger.kernel.org, rcampbell@nvidia.com, Tim Murray , Linus Torvalds , Vlastimil Babka , Matthew Wilcox Message-ID: <2084584347.3560.1575351504972.JavaMail.zimbra@efficios.com> In-Reply-To: References: <20191201015030.MR-ux4mV1%akpm@linux-foundation.org> <20191202121415.1e64a461@gandalf.local.home> <20191202211345.GE17234@google.com> <20191202165601.42366c21@gandalf.local.home> <20191202234514.GR17234@google.com> <20191202185324.30b502bb@gandalf.local.home> Subject: Re: [patch 026/158] mm: emit tracepoint when RSS changes MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [167.114.142.138] X-Mailer: Zimbra 8.8.15_GA_3888 (ZimbraWebClient - FF70 (Linux)/8.8.15_GA_3890) Thread-Topic: emit tracepoint when RSS changes Thread-Index: 41eg+PYCea69049b9SZTLN9EGiIZUg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: ----- On Dec 2, 2019, at 9:48 PM, Primiano Tucci primiano@google.com wrote: > On Mon, Dec 2, 2019 at 11:53 PM Steven Rostedt wrote: > On Mon, 2 Dec 2019 18:45:14 -0500 > Joel Fernandes wrote: > >> >> I would love for that to happen but I don't develop Perfetto much. If I am >> writing a tool I will definitely give it a go from my side. CC'ing Perfetto's >> lead developer Primiano -- I believe you have already met Primiano at a >> conference before as he mentioned it to me that you guys met. I also believe >> this topic of using a common library was discussed before, but something >> about licensing came up. > > Oh hello again! > >> libtraceevent is under LGPL, is that an issue? > > Unfortunately yes, it is :/ > Our process for incorporating GPL or LGPL code makes Perfetto [1] (which is > Apache-2 licensed) problematic for us and recursively for other projects that > depend on us. > > For context, Perfetto is a cross-platform tracing project based on shmem and > protobuf, shipped on production devices and used by other app-developer-facing > tools (e.g. [6, 7]). It deals with both: > (1) pure userspace-to-userspace tracing (on all major OSs). > (2) kernel tracing via ftrace/tracefs (only on Linux/Android). > https://docs.perfetto.dev/ explains it a bit more. > > Today Perfetto is embedded and used both by Chrome [2] and Android platform [3]. > For both projects, pulling LGPL-licensed code is cumbersome process-wise: It > would require us to put mechanism in place to guarantee that the relevant LGPL > dependencies don't get accidentally linked in any production binary but only > used for the standalone offline tools to analyze traces. > Such process is unfortunately very expensive to setup and maintain for us and > for the projects that depend on us. > I don't want to start an ideological battle about licensing. To be clear, I > don't have any issues with LGPL, nor I think there's anything inherently > wrong with it. Just, it makes things too complicated when a smaller sub-project > like ours is embedded in larger projects. Just to clarify: my understanding is that a constraint that requires no dynamic linking of proprietary code on LGPL libraries does not seem to originate from restrictions based on the wording of the LGPL text. So it appears to be self-imposed either by your employer's (or your own) additional requirements, so not to bother dealing with the legal side of compliance, am I correct ? Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com