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=-3.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_REPLYTO_END_DIGIT, 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 EF350C2B9F4 for ; Thu, 17 Jun 2021 22:13:57 +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 30E3E61249 for ; Thu, 17 Jun 2021 22:13:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 30E3E61249 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 4G5btW1HwZzJ4N; Thu, 17 Jun 2021 18:13:55 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=lists.lttng.org; s=default; t=1623968036; bh=b3hYp6hh3fTt0feH6FWNOEqTftPz71Oz0us7SBUQS6s=; h=Date:To:Subject:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:From; b=vCqMEqyeIhnYP5OdvmH6MJRymH5hGXt0AyaDw3nFCb+3SIJxTa9pV/6G2IFh0P1j5 o9dD3EgG6Z71GV1WhOAKc5PZZuE06Q+zeprvMu6JywStTX1DLi39hGWI8oqnHQAizB 3CpGwB8pqveGYvy5fZVVTTupV3ZhasHAof7jGdY7NLOSZIr8Ff8iS85x46B5eWd1vV MqU0+0+jJbVviW4tihUg16kMqgtH2NhVs27xmoR0on2KYXbUq+6L1oQt9IaN78++eS aKyKmOqja9lBqOtuPAH3m2XCgBQFydJ2cGDKcLv/qMQtsk7pJKn1/+dvmKNPSfA3Ln ACnukoDLJnt2A== Received: from mail-ot1-x32f.google.com (mail-ot1-x32f.google.com [IPv6:2607:f8b0:4864:20::32f]) by lists.lttng.org (Postfix) with ESMTPS id 4G5btT49HqzJ5N for ; Thu, 17 Jun 2021 18:13:53 -0400 (EDT) Received: by mail-ot1-x32f.google.com with SMTP id 6-20020a9d07860000b02903e83bf8f8fcso7693211oto.12 for ; Thu, 17 Jun 2021 15:13:53 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=JF0W1fEZ1vjZl6czrPoSLj+lze1ctrs9ZOMbUPBxCkg=; b=rgGmJoNFFZF3tZ2OlnxprMtl1jJ7aW2HDizTN7byDvXT2eUOCAghXlp57WZBIRCJqL WTmcmWf++eABvbt7OSMTJiET74ZKXaFCnymnpfl0z58iCrC5mPq+xxqt8ZWDpde3jIUq upfU6+sgfk8pdrd+9hT5Bi/H5CSrQ+5LWnfYDZ+PLOIz7MVjIVThB0CkDrRaN5e/EL+O gYr1adqfDEgIZ4t7ewWWLXAxbX9V7JwWgE0vaznqoNzZ7cEuixD/E5YruAGPd7WQPXOx 9B5BffryXJ9ZqU+gyiV8qtQk0FIlotM9Rl9MhKs9xPujXcIMGD0f51ykupXONkrSvotl eiBw== X-Gm-Message-State: AOAM531ogjCZuZ3/nodZqQBgTrPt8yfiGddiurKaSiGZNWPwUFtieyYB zBGvViwP7obst2MeRsYcpU3/CTLU1Nu/pdd+twFv71auFGVD0A== X-Google-Smtp-Source: ABdhPJxrWVd6lsQsmjswsOquzbrve6SesQdT4/n/sZ1+5AFrHqP4rK2KgeLluwhqcGWbxZFWDYSmpkIZufR7swle1ok= X-Received: by 2002:a9d:5c14:: with SMTP id o20mr6205350otk.328.1623968030619; Thu, 17 Jun 2021 15:13:50 -0700 (PDT) MIME-Version: 1.0 Date: Fri, 18 Jun 2021 00:13:39 +0200 Message-ID: To: lttng-dev Subject: [lttng-dev] Disabling sys_membarrier in lttng urcu 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: Norbert Lange via lttng-dev Reply-To: Norbert Lange Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: lttng-dev-bounces@lists.lttng.org Sender: "lttng-dev" Hello, Some old topic, see https://lists.lttng.org/pipermail/lttng-dev/2019-November/029411.html. (I actually thought this was solved meanwhile). With lttng 2.13 liburcu is replicated in lttng-ust so my old custom hack aint helping. Aside from another crude hack, I thought about doing this: extern int lttng_ust_urcu_has_sys_membarrier; int setup() { lttng_ust_urcu_has_sys_membarrier = 0; } this is obvious possible in my own program, but I don't know if some lttng daemon would need to update RCU structures in shared memory that should sync to other processes (and wont do that with sys_membarrier in case of Xenomai threads)? Seems safer to me to hack it out once more... Norbert _______________________________________________ lttng-dev mailing list lttng-dev@lists.lttng.org https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev