From owner-freebsd-stable@FreeBSD.ORG Fri Oct 3 13:33:57 2008 Return-Path: Delivered-To: freebsd-stable@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 09E341065691 for ; Fri, 3 Oct 2008 13:33:57 +0000 (UTC) (envelope-from nox@saturn.kn-bremen.de) Received: from gwyn.kn-bremen.de (gwyn.kn-bremen.de [212.63.36.242]) by mx1.freebsd.org (Postfix) with ESMTP id 82AE38FC18 for ; Fri, 3 Oct 2008 13:33:56 +0000 (UTC) (envelope-from nox@saturn.kn-bremen.de) Received: by gwyn.kn-bremen.de (Postfix, from userid 10) id 3BF33191A71; Fri, 3 Oct 2008 15:33:54 +0200 (CEST) Received: from saturn.kn-bremen.de (noident@localhost [127.0.0.1]) by saturn.kn-bremen.de (8.14.2/8.13.8) with ESMTP id m93DG1X1005596 for ; Fri, 3 Oct 2008 15:16:01 +0200 (CEST) (envelope-from nox@saturn.kn-bremen.de) Received: (from nox@localhost) by saturn.kn-bremen.de (8.14.2/8.13.6/Submit) id m93DG0uW005595 for freebsd-stable@FreeBSD.org; Fri, 3 Oct 2008 15:16:00 +0200 (CEST) (envelope-from nox) From: Juergen Lock Date: Fri, 3 Oct 2008 15:16:00 +0200 To: freebsd-stable@FreeBSD.org Message-ID: <20081003131600.GA5421@saturn.kn-bremen.de> Mail-Followup-To: freebsd-stable@FreeBSD.org References: <20080917204107.GA11167@saturn.kn-bremen.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080917204107.GA11167@saturn.kn-bremen.de> User-Agent: Mutt/1.5.17 (2007-11-01) Cc: Subject: Re: dtrace: processing aborted: Abort due to systemic unresponsiveness (dtrace_gethrtime()?) - and kgdb X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 03 Oct 2008 13:33:57 -0000 On Wed, Sep 17, 2008 at 10:41:07PM +0200, I wrote: > Hi! > > I got curious in dtrace, and after mr's sys/amd64/amd64/trap.c > commit (r183050, thanx! :) I was able to build a kernel that could > kldload dtraceall on 7-stable amd64, but trying even simple things like > dtrace -n tick-1sec > only runs for a short time, or not at all, ending with $subject: > > # dtrace -n tick-1sec > dtrace: description 'tick-1sec' matched 1 probe > dtrace: buffer size lowered to 2m > CPU ID FUNCTION:NAME > 1 32125 :tick-1sec > dtrace: processing aborted: Abort due to systemic unresponsiveness > # dtrace -n tick-1sec > dtrace: description 'tick-1sec' matched 1 probe > dtrace: buffer size lowered to 2m > dtrace: processing aborted: Abort due to systemic unresponsiveness > # > > Looking around on the net I find that this is probably related to > dtrace_gethrtime() (this box is SMP), which I see defined in > sys/amd64/amd64/tsc.c, but also in sys/cddl/dev/dtrace/amd64/dtrace_subr.c, > and in sys/cddl/dev/dtrace/i386/dtrace_subr.c, but nowhere under sys/i386. > The versions in sys/cddl/dev/dtrace take cpu-dependent tsc offsets into > account which the one in sys/amd64/amd64/tsc.c doesn't, is there any > particular reason this version is used? Also I don't see it in HEAD... > I since found out two things: a) the version of dtrace_gethrtime() in sys/amd64/amd64/tsc.c is indeed not needed, and b) removing it still didn't fix my problem, stopping powerd then did, even with the original kernel. Doh! :) Anyway, I'm still pretty sure the #ifdef KDTRACE_HOOKS code in sys/amd64/amd64/tsc.c can go, the version of dtrace_gethrtime() in sys/cddl/dev/dtrace/amd64/dtrace_subr.c looks more correct at least... Thanx, Juergen