From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 9117 invoked by alias); 12 Sep 2012 11:17:11 -0000 Received: (qmail 9110 invoked by uid 22791); 12 Sep 2012 11:17:10 -0000 X-SWARE-Spam-Status: No, hits=-6.2 required=5.0 tests=AWL,BAYES_00,KHOP_RCVD_UNTRUST,RCVD_IN_DNSWL_HI,RCVD_IN_HOSTKARMA_W,RP_MATCHES_RCVD,SPF_HELO_PASS X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 12 Sep 2012 11:16:51 +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 q8CBGoow007053 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Wed, 12 Sep 2012 07:16:50 -0400 Received: from fche.csb (vpn-9-31.rdu.redhat.com [10.11.9.31]) by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id q8CBGn10032208; Wed, 12 Sep 2012 07:16:49 -0400 Received: by fche.csb (Postfix, from userid 2569) id 2A39758145; Wed, 12 Sep 2012 07:16:49 -0400 (EDT) Date: Wed, 12 Sep 2012 11:17:00 -0000 From: "Frank Ch. Eigler" To: Jeff Haran Cc: "'systemtap@sourceware.org'" Subject: Re: accessing target globals with systemtap Message-ID: <20120912111648.GA22100@redhat.com> References: <7914B38A4445B34AA16EB9F1352942F1012F0F957558@SJCPMAILBOX01.citrite.net> <7914B38A4445B34AA16EB9F1352942F1012F0F957559@SJCPMAILBOX01.citrite.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7914B38A4445B34AA16EB9F1352942F1012F0F957559@SJCPMAILBOX01.citrite.net> User-Agent: Mutt/1.4.2.2i Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org X-SW-Source: 2012-q3/txt/msg00296.txt.bz2 Hi - On Tue, Sep 11, 2012 at 05:59:58PM -0700, Jeff Haran wrote: > [...] > 1235 void __init arp_init(void) > [...] It does look like a tasty little tidbit. Unfortunately, __init functions in the kernel are normally tossed into the memory hole right after bootup, so are not available for probing by the time we proles come along. With a "stap --vp 02" option added, you'll get a hint at the problem: probe arp_init@net/ipv4/arp.c:1276 kernel reloc=.dynamic pc=0xffffffff81bb7f6f init/exit - skipped > [...] > Also, what is the recommended way of getting the address of an in-scope structure instance? > > As you've pointed out this is wrong: > arp_tbl = $arp_tbl > Is this the way to do it? > arp_tbl = &$arp_tbl Yes. - FChE