From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 14599 invoked by alias); 30 Apr 2010 03:19:42 -0000 Received: (qmail 14587 invoked by uid 22791); 30 Apr 2010 03:19:41 -0000 X-SWARE-Spam-Status: No, hits=-1.9 required=5.0 tests=BAYES_00,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mail.codesourcery.com (HELO mail.codesourcery.com) (38.113.113.100) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 30 Apr 2010 03:19:36 +0000 Received: (qmail 8541 invoked from network); 30 Apr 2010 03:19:35 -0000 Received: from unknown (HELO macbook-2.local) (stan@127.0.0.2) by mail.codesourcery.com with ESMTPA; 30 Apr 2010 03:19:35 -0000 Message-ID: <4BDA4C34.1010708@codesourcery.com> Date: Fri, 30 Apr 2010 03:19:00 -0000 From: Stan Shebs User-Agent: Thunderbird 2.0.0.24 (Macintosh/20100228) MIME-Version: 1.0 To: Michael Snyder CC: Stan Shebs , "gdb-patches@sourceware.org" Subject: Re: [RFC] Observer mode References: <4BD9C057.9090805@codesourcery.com> <4BD9CC1D.9040104@vmware.com> In-Reply-To: <4BD9CC1D.9040104@vmware.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit 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 X-SW-Source: 2010-04/txt/msg00976.txt.bz2 Michael Snyder wrote: > Stan Shebs wrote: >> Here is another patch that pushes the envelope a bit, and for which I >> would like to get some prior agreement that it's a good idea. >> >> The basic idea here is that GDB is to be used to look at targets >> installed in the field and in use. In such a situation it may >> connect to the target and examine state, but not alter that state or >> interrupt anything. In our particular target, tracing is allowed, >> but only using fast tracepoints, because they are done using jumps >> and thus act as if they were part of the program; taking a trap, even >> for a slow tracepoint, disrupts thread execution unacceptably. We >> have been calling this "observer mode", and the customer's GDB is >> actually configured to launch in this mode, to reduce the chance of >> accidental stopping - the debugger user has to ask specifically to >> change it to normal debugging mode. >> >> [...] > > How different is this from async mode? Observer mode includes async mode. One could call it a "read-only non-stop async mode that allows fast tracepoints", although that's rather a mouthful. :-) Stan