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=-5.8 required=3.0 tests=BAYES_00,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 D58EBC433ED for ; Thu, 20 May 2021 16:25:47 +0000 (UTC) Received: from lists.lttng.org (lists.lttng.org [167.114.26.123]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0C8F4606A5 for ; Thu, 20 May 2021 16:25:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0C8F4606A5 Authentication-Results: mail.kernel.org; dmarc=pass (p=none dis=none) header.from=lists.lttng.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lttng-dev-bounces@lists.lttng.org Received: from lists-lttng01.efficios.com (localhost [IPv6:::1]) by lists.lttng.org (Postfix) with ESMTP id 4FmFTh3XJTz1s42; Thu, 20 May 2021 12:25:44 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=lists.lttng.org; s=default; t=1621527945; bh=9EG9O/c0iPCnE/DD36geu/mFifwsF1UvcwKyeahZKQY=; h=Date:To:Cc:In-Reply-To:References:Subject:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From:Reply-To:From; b=W/TzvglOZruB5++DZiwY+J3kB3DFz8E5IJtVI/FOqtR3Bn/lxRtRdlSP1DGVX2qh4 cxoGvKMXKsPXPityfmkc0RL/GcSBYX3eVIhfs5HB+8wqiD61Cm681zEHuIMwvXVZcJ aFEU/TFs2Mu7Ak4nIHgT3UM4msdE4viYCizw8ZX+8eh307tGjl9FWF6+VPNguKqHiD lyprEuycNPeQJ+XtRYXH7jzhtgW5qhZVgpDME4fVIVoVG9+8Nmd20VT6r2v3amSzKS bZk0Qvb+W2nKHXZ8/hVgKDKFgNCBBkWlEyYW0VR8/tjBET7Ql0SQevq3z0DkZyG1Ve IVdJ2zMUPYXLg== Received: from mail.efficios.com (mail.efficios.com [167.114.26.124]) by lists.lttng.org (Postfix) with ESMTPS id 4FmFTg1tCNz1s5q for ; Thu, 20 May 2021 12:25:43 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id C697433712D for ; Thu, 20 May 2021 12:25:37 -0400 (EDT) Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id JrFcLH0Xo9vT; Thu, 20 May 2021 12:25:35 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id BD51A33712B; Thu, 20 May 2021 12:25:35 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com BD51A33712B X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id Zo2B7Qn1JfME; Thu, 20 May 2021 12:25:35 -0400 (EDT) Received: from mail03.efficios.com (mail03.efficios.com [167.114.26.124]) by mail.efficios.com (Postfix) with ESMTP id AF023336EF5; Thu, 20 May 2021 12:25:35 -0400 (EDT) Date: Thu, 20 May 2021 12:25:35 -0400 (EDT) To: Norbert Lange Cc: lttng-dev Message-ID: <523808152.52514.1621527935563.JavaMail.zimbra@efficios.com> In-Reply-To: References: <20210520121807.55428-1-nolange79@gmail.com> <1600729511.52338.1621520352970.JavaMail.zimbra@efficios.com> <982122605.52445.1621524098787.JavaMail.zimbra@efficios.com> MIME-Version: 1.0 X-Originating-IP: [167.114.26.124] X-Mailer: Zimbra 8.8.15_GA_4018 (ZimbraWebClient - FF88 (Linux)/8.8.15_GA_4007) Thread-Topic: Improve tracelog handling, reduce exported functions Thread-Index: A/ABAU9NCXIwzjHgoQs9TVyi/x7FvQ== Subject: Re: [lttng-dev] [PATCH lttng-ust] Improve tracelog handling, reduce exported functions X-BeenThere: lttng-dev@lists.lttng.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: LTTng development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Mathieu Desnoyers via lttng-dev Reply-To: Mathieu Desnoyers Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: lttng-dev-bounces@lists.lttng.org Sender: "lttng-dev" ----- On May 20, 2021, at 11:54 AM, Norbert Lange nolange79@gmail.com wrote: [...] >> What prevents you from linking against lttng-ust.so again ? > > I did not poke around enough with Lttng to be confident it wont have > side effects, > I really don't want it active in production. It doesn't seem there is > much public knowledge with Xenomai either. > lttng-ust.so will spawn threads, lttng-ust-tracepoint.so is mostly passive, There is indeed a split between instrumentation and runtime threads done with lttng-ust-tracepoint.so vs lttng-ust.so. I understand that this split is missing for tracelog and tracef, and would be a good thing to have. I would be interested to move the tracelog and tracef implementation from liblttng-ust.so to liblttng-ust-tracepoint.so, even this late in the -rc cycle, because all users of tracelog/tracef need to link against liblttng-ust-tracepoint.so anyway. So moving these symbols should not affect anyone. Can you give it a try and let me know if it works for you ? > So Id want a dynamic tracepoint-provider than i can dlopen (so that > the signal masks are inherited, > I hope you dont touch them). The signals are all blocked for lttng-ust listener threads. We don't modify the signal masks in the tracepoint probes. Not sure which is the target of your question though. > > Of course I could just remove all lttng libraries on the production > system aswell. Still doesnt change that > tracelog and tracef doesnt work that way. Would moving the tracelog/tracef implementation to liblttng-ust-tracepoint.so solve your issues ? > > I implemented my own tracelog/tracef using the normal lttng > tracepoints for now, they totally break on source level with 2.13 > aswell ;) > is it ok if I do this to access them: > > #define TRACEPOINT_DEFINE > #define TRACEPOINT_PROBE_DYNAMIC_LINKAGE > // 2.12 > // #include > // #include > // 2.13 > #include > #include > > ie. I would load lttng-ust.so later and can then use those tracepoints. Reimplementing the tracelog/tracef providers is not an intended use-case. I'd very much prefer if we move their implementation to liblttng-ust-tracepoint.so. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com _______________________________________________ lttng-dev mailing list lttng-dev@lists.lttng.org https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev