From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 17280 invoked by alias); 22 Jan 2007 19:00:49 -0000 Received: (qmail 17268 invoked by uid 22791); 22 Jan 2007 19:00:46 -0000 X-Spam-Status: No, hits=-2.6 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,SPF_PASS X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (66.187.233.31) by sourceware.org (qpsmtpd/0.31) with ESMTP; Mon, 22 Jan 2007 19:00:39 +0000 Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com [172.16.52.254]) by mx1.redhat.com (8.12.11.20060308/8.12.11) with ESMTP id l0MJ0ZfJ027592; Mon, 22 Jan 2007 14:00:35 -0500 Received: from pobox.corp.redhat.com (pobox.corp.redhat.com [10.11.255.20]) by int-mx1.corp.redhat.com (8.13.1/8.13.1) with ESMTP id l0MJ0XTw007776; Mon, 22 Jan 2007 14:00:33 -0500 Received: from [127.0.0.1] (sebastian-int.corp.redhat.com [172.16.52.221]) by pobox.corp.redhat.com (8.13.1/8.12.8) with ESMTP id l0MJ0V0n014984; Mon, 22 Jan 2007 14:00:32 -0500 Message-ID: <45B509C5.2000908@redhat.com> Date: Mon, 22 Jan 2007 19:00:00 -0000 From: Andrew Cagney User-Agent: Thunderbird 1.5.0.9 (X11/20070102) MIME-Version: 1.0 To: Mark Wielaard CC: Phil Muldoon , frysk@sourceware.org Subject: Re: fstep added References: <1166450488.3022.19.camel@dijkstra.wildebeest.org> <4586BC16.6090208@redhat.com> <45B4C173.5010909@redhat.com> <1169482750.29512.1.camel@hermans.wildebeest.org> In-Reply-To: <1169482750.29512.1.camel@hermans.wildebeest.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact frysk-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: frysk-owner@sourceware.org X-SW-Source: 2007-q1/txt/msg00034.txt.bz2 Unfortunatly current kernels don't allow mmapping of /proc/PID/maps; however open/pread works. Andrew Mark Wielaard wrote: > On Mon, 2007-01-22 at 07:51 -0600, Phil Muldoon wrote: > >> Resurrecting this thread for a little bit. Is this issue related to: >> >> http://sourceware.org/bugzilla/show_bug.cgi?id=3727 >> >> I'm hazarding a guess this all comes down to ptrace accessing the >> inferior's memory word by word, and that optimizations made in access to >> the inferior's memory (ie by mmaping /proc/$$/memory) will benefit fcore >> as well as fstep? My knowledge here is really fuzzy. >> > > Yes and http://sourceware.org/bugzilla/show_bug.cgi?id=3761 which are > basically the same issue. To speedup fstep and fcore) we would like to > mmap /proc//mem for the inferior and wrap it in an inua ByteBuffer. > This doesn't provide write access, but we do reads mostly anyway. You > can imagine a ByteBuffer returned by Task.getMemory() that delegates > reads through such an mmap backed inua ByteBuffer and writes delegated > through a ptrace backed inua ByteBuffer. > > Cheers, > > Mark > >