From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-Status: No, score=-4.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,MAILING_LIST_MULTI, SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from sourceware.org (server2.sourceware.org [IPv6:2620:52:3:1:0:246e:9693:128c]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by dcvr.yhbt.net (Postfix) with ESMTPS id EE2E11F55B for ; Wed, 27 May 2020 15:05:37 +0000 (UTC) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id B0E40396EC7E; Wed, 27 May 2020 15:05:36 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org B0E40396EC7E DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1590591936; bh=//SmQFvwBNz2ylfQZyG5/kJK9H2Y20TQtTPUG8ZZfS4=; h=Date:To:In-Reply-To:References:Subject:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=guQgIrImfApJsxUiT/PEtL/0jS8oEpZYvuKp3vR0AEotyP6SjjC2rn19mE3SpouET 7psgcY3DG02wrOhQkoYi0dOGjsO8REzQV5/VMdz/wCWW3qfeedq9dI74ESQsI2WSl2 z9L2H5BjnrxGnuosyqsC0IYxzheJLwwCP7mPbd14= Received: from mail.efficios.com (mail.efficios.com [167.114.26.124]) by sourceware.org (Postfix) with ESMTPS id 70C72395B0B1 for ; Wed, 27 May 2020 15:05:33 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 70C72395B0B1 Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id F287326F339; Wed, 27 May 2020 11:05:32 -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 bMEqgr2MGK43; Wed, 27 May 2020 11:05:32 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id BC8E426F422; Wed, 27 May 2020 11:05:32 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com BC8E426F422 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 wzqnLQiQ9MkJ; Wed, 27 May 2020 11:05:32 -0400 (EDT) Received: from mail03.efficios.com (mail03.efficios.com [167.114.26.124]) by mail.efficios.com (Postfix) with ESMTP id B1B4626F421; Wed, 27 May 2020 11:05:32 -0400 (EDT) Date: Wed, 27 May 2020 11:05:32 -0400 (EDT) To: Florian Weimer Message-ID: <1975648335.36785.1590591932673.JavaMail.zimbra@efficios.com> In-Reply-To: <1647263261.34186.1590504195448.JavaMail.zimbra@efficios.com> References: <20200501021439.2456-1-mathieu.desnoyers@efficios.com> <20200501021439.2456-4-mathieu.desnoyers@efficios.com> <871rnedgjg.fsf@oldenburg2.str.redhat.com> <1384708804.33510.1590426460701.JavaMail.zimbra@efficios.com> <87h7w2rhg2.fsf@oldenburg2.str.redhat.com> <1647263261.34186.1590504195448.JavaMail.zimbra@efficios.com> Subject: Re: [PATCH glibc 3/3] rseq registration tests (v10) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [167.114.26.124] X-Mailer: Zimbra 8.8.15_GA_3928 (ZimbraWebClient - FF76 (Linux)/8.8.15_GA_3928) Thread-Topic: rseq registration tests (v10) Thread-Index: YPfIt1dIPVeJ6nTlxheYfou8BfxIAXhusdnK X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Mathieu Desnoyers via Libc-alpha Reply-To: Mathieu Desnoyers Cc: libc-alpha , Joseph Myers Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" ----- On May 26, 2020, at 10:43 AM, Mathieu Desnoyers mathieu.desnoyers@efficios.com wrote: > ----- On May 26, 2020, at 8:47 AM, Florian Weimer fweimer@redhat.com wrote: > >> * Mathieu Desnoyers: [...] The one question below is the last thing we need to complete discussing before I can re-spin another version of the patches: >> >>>>> + retpid = TEMP_FAILURE_RETRY (waitpid (pid, &status, 0)); >>>>> + if (retpid != pid) >>>>> + { >>>>> + FAIL_EXIT1 ("waitpid returned %ld, expected %ld", >>>>> + (long int) retpid, (long int) pid); >>>>> + } >>>> >>>> Hmm. Is the TEMP_FAILURE_RETRY really needed? Our xwaitpid does not >>>> have this. >>> >>> Then how does it deal with a signal interrupting the system call performing >>> the waitpid (EINTR) ? I do not see WNOHANG being used. >> >> It obscures spurious signals. In most test cases, if an unexpected >> signal is delivered, something is quite wrong indeed. This is why we >> don't generally hide EINTR errors. > > So it means you may have trouble using tools like strace and gdb on those > tests ? AFAIU those are heavy users of SIGSTOP and SIGCONT. Similarly for > profilers, those usually rely on a timer-driven signal. > Should I use xwaitpid instead, and should xwaitpid be fixed to use TEMP_FAILURE_RETRY ? Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com