From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 7539 invoked by alias); 15 Dec 2014 16:01:23 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 7527 invoked by uid 89); 15 Dec 2014 16:01:22 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.0 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,SPF_PASS,T_RP_MATCHES_RCVD autolearn=ham version=3.3.2 X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES256-GCM-SHA384 encrypted) ESMTPS; Mon, 15 Dec 2014 16:01:21 +0000 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id sBFG1IM4009635 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 15 Dec 2014 11:01:19 -0500 Received: from [127.0.0.1] (ovpn01.gateway.prod.ext.ams2.redhat.com [10.39.146.11]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id sBFG1HXs016983; Mon, 15 Dec 2014 11:01:18 -0500 Message-ID: <548F05CC.9090804@redhat.com> Date: Mon, 15 Dec 2014 16:01:00 -0000 From: Pedro Alves User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: Joel Brobecker CC: gdb-patches@sourceware.org Subject: Re: RFC: skip_inline_frames failed assertion resuming from breakpoint on LynxOS References: <20141120051109.GR5774@adacore.com> <20141120051223.GA23720@adacore.com> <546DBA9F.9060600@redhat.com> <20141120171137.GT5774@adacore.com> <546F173A.3070204@redhat.com> <20141213154638.GK5457@adacore.com> <548EDE03.7090005@redhat.com> <20141215145827.GY5457@adacore.com> In-Reply-To: <20141215145827.GY5457@adacore.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-SW-Source: 2014-12/txt/msg00396.txt.bz2 On 12/15/2014 02:58 PM, Joel Brobecker wrote: >> GDB nowadays sends a single vCont packet that both steps thread A, >> continues thread B with a signal and continues all other threads with >> no signal (previously in some cases it'd just lose control of the >> inferior, or deliver the signal to the wrong thread). Something like: >> >> vCont;s:A;C SIG:B;c > [...] >> Couldn't you iterate over the threads, and use PTRACE_STEP_ONE >> for the stepped threads, and PTRACE_CONT_ONE for the others, >> instead of PTRACE_CONT ? For the case above, lynx_resume would >> end up issuing: >> >> PTRACE_STEP_ONE, thread A, sig 0 >> PTRACE_CONT_ONE, thread B, sig SIG >> PTRACE_CONT_ONE, thread C, sig 0 >> PTRACE_CONT_ONE, thread D, sig 0 > > Interesting. Do you mean sending those requests without waiting > for the inferior to stop? Yes. This is what we do e.g., on Linux. It just sounds like Lynx's PTRACE_CONT_ONE is like Linux's PTRACE_CONT. Linux has no equivalent of Lynx's PTRACE_CONT (resume all threads with a single request). > I'd have to verify that it's possible > to send ptrace requests while the inferior is "in flight", but > wouldn't you then have possible race conditions? Not sure what sort of race conditions you mean, but keep in mind that I'm pretty clueless about Lynx. :-) Thanks, Pedro Alves