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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 DC731C43387 for ; Mon, 14 Jan 2019 18:57:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B65E7206B7 for ; Mon, 14 Jan 2019 18:57:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726821AbfANS5M (ORCPT ); Mon, 14 Jan 2019 13:57:12 -0500 Received: from mx1.redhat.com ([209.132.183.28]:43780 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726753AbfANS5M (ORCPT ); Mon, 14 Jan 2019 13:57:12 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A786F653C2; Mon, 14 Jan 2019 18:57:11 +0000 (UTC) Received: from oldenburg2.str.redhat.com (ovpn-116-20.ams2.redhat.com [10.36.116.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 6D0C15D9CA; Mon, 14 Jan 2019 18:57:05 +0000 (UTC) From: Florian Weimer To: Mathieu Desnoyers Cc: carlos , Joseph Myers , Szabolcs Nagy , libc-alpha , Thomas Gleixner , Ben Maurer , Peter Zijlstra , "Paul E. McKenney" , Boqun Feng , Will Deacon , Dave Watson , Paul Turner , Rich Felker , linux-kernel , linux-api Subject: Re: [RFC PATCH glibc 1/4] glibc: Perform rseq(2) registration at nptl init and thread creation (v4) References: <20181204192141.4684-1-mathieu.desnoyers@efficios.com> <87h8fkz6qx.fsf@oldenburg2.str.redhat.com> <1681283664.1380.1547152315426.JavaMail.zimbra@efficios.com> <1488546469.1564.1547169116539.JavaMail.zimbra@efficios.com> Date: Mon, 14 Jan 2019 19:57:03 +0100 In-Reply-To: <1488546469.1564.1547169116539.JavaMail.zimbra@efficios.com> (Mathieu Desnoyers's message of "Thu, 10 Jan 2019 20:11:56 -0500 (EST)") Message-ID: <87bm4j9if4.fsf@oldenburg2.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Mon, 14 Jan 2019 18:57:11 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Mathieu Desnoyers: > Now that I think about it, it's important to move the rseq registration > done at nptl init (in my current code) to some lower-level csu initialiation, > so applications that happen _not_ to link against libpthread also get > registered rseq for the main thread. Yes. In general, we want to avoid to force libraries which do not create threads to link against libpthread, and try to provide interfaces which are required for synchronization within libc. Thanks, Florian