From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 3457 invoked by alias); 11 Dec 2013 19:57:36 -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 3441 invoked by uid 89); 11 Dec 2013 19:57:35 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-4.2 required=5.0 tests=AWL,BAYES_00,RP_MATCHES_RCVD,SPF_HELO_PASS,SPF_PASS 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 ESMTP; Wed, 11 Dec 2013 19:57:34 +0000 Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id rBBJvVab028785 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Wed, 11 Dec 2013 14:57:32 -0500 Received: from host2.jankratochvil.net (ovpn-116-40.ams2.redhat.com [10.36.116.40]) by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id rBBJvStj031532 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Wed, 11 Dec 2013 14:57:30 -0500 Date: Wed, 11 Dec 2013 19:57:00 -0000 From: Jan Kratochvil To: "Metzger, Markus T" Cc: "gdb-patches@sourceware.org" Subject: Re: [+rfc] Re: [patch v6 00/21] record-btrace: reverse Message-ID: <20131211195728.GA22596@host2.jankratochvil.net> References: <1379676639-31802-1-git-send-email-markus.t.metzger@intel.com> <20131006195913.GA2518@host2.jankratochvil.net> <20131127185727.GA18038@host2.jankratochvil.net> <20131128211623.GA16695@host2.jankratochvil.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-IsSubscribed: yes X-SW-Source: 2013-12/txt/msg00448.txt.bz2 On Fri, 29 Nov 2013 15:00:22 +0100, Metzger, Markus T wrote: > Here I still have problems with multi-threaded inferiors. When I switch to > a different thread and then "record goto", I get a "No more reverse-execution > history" error followed by a "Record goto failed" error. > > I believe that "record goto" is resuming the wrong thread after I switch away > from the eventing thread. Curiously, this does not seem to be a problem if > I do not set tp->control.exception_resume_breapoint. This needs some > more debugging. > > > On a related topic, when we implement "record goto" via resume/wait, we will > trigger breakpoints at the target location. This might or might not be desired. > We do not trigger breakpoints on our way to the record goto target location. > Again, this might or might not be desired. > > Record full's "record goto" command does not trigger breakpoints; neither at > the target location nor on its way. In fact, record full does not implement > "record goto" via resume/wait. Instead, it single-steps through its execution > history in a simple do-while loop, similar to what I am doing in record btrace. Execution of commands of a breakpoint at the target location is sure a bug, I did not realize it. Thanks for finding it. I was now looking how to suppress them but I do not think there is an easy soltuion. So I think your previous code without resume+wait during goto was better and the changes should be reverted. It will hopefully also fix the multi-threading bug above I have not investigated. Could you do a hopefully final v8 post? Thanks, Jan