From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 2022 invoked by alias); 31 Oct 2013 13:24:19 -0000 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 Received: (qmail 1984 invoked by uid 89); 31 Oct 2013 13:24:14 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-4.4 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; Thu, 31 Oct 2013 13:24:13 +0000 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r9VDNV55018040 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 31 Oct 2013 09:23:31 -0400 Received: from [10.36.116.35] (ovpn-116-35.ams2.redhat.com [10.36.116.35]) by int-mx02.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id r9VDNRPW030408; Thu, 31 Oct 2013 09:23:27 -0400 Subject: Re: [PATCH v4 2/3] Support for perf to probe into SDT markers: From: Mark Wielaard To: Ingo Molnar Cc: Pekka Enberg , Masami Hiramatsu , "Frank Ch. Eigler" , Pekka Enberg , Hemant Kumar , LKML , Srikar Dronamraju , Peter Zijlstra , Oleg Nesterov , hegdevasant@linux.vnet.ibm.com, Ingo Molnar , anton@redhat.com, systemtap@sourceware.org, Namhyung Kim , aravinda@linux.vnet.ibm.com, dsahern@gmail.com, "yrl.pp-manager.tt@hitachi.com" In-Reply-To: <20131031105759.GB12066@gmail.com> References: <20131023044511.1886.82571.stgit@hemant-fedora> <20131023050502.1886.15779.stgit@hemant-fedora> <5270D9F7.3090105@hitachi.com> <5270F2DE.6040505@iki.fi> <1383216886.6521.5910.camel@bordewijk.wildebeest.org> <20131031105759.GB12066@gmail.com> Content-Type: text/plain; charset="UTF-8" Date: Thu, 31 Oct 2013 13:24:00 -0000 Message-ID: <1383225806.6521.6105.camel@bordewijk.wildebeest.org> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-SW-Source: 2013-q4/txt/msg00146.txt.bz2 On Thu, 2013-10-31 at 11:57 +0100, Ingo Molnar wrote: > * Mark Wielaard wrote: > > On Wed, 2013-10-30 at 13:51 +0200, Pekka Enberg wrote: > > > On 10/30/13 12:05 PM, Masami Hiramatsu wrote: > > > > To find all system libraries, we can use ldconfig. > > > > > > > > $ ldconfig --print-cache > > > > > > > > shows what dynamic libraries will be loaded. On my own laptop (running > > > > ubuntu13.04) shows ~1000 libs. > > > > > > Good point. That definitely narrows down the scanned set. > > > > It is fast. But that would miss the various libjvm.so variants for > > example. Or other programs, like libreoffice, which have SDT > > probes in their internal shared libraries that aren't in the > > default ldconfig paths. > > I suppose those Java libraries ought to show up in > /etc/prelink.cache though, right? Good point. Yes, all executables and libraries I was missing in ldconfig --print-cache do show up with prelink -p. Except libjvm.so itself... Apparently prelink is convinced that really is never used. hmmm. Apparently all wrapper "java" executables only dlopen it, so it is never directly linked, and prelink doesn't cache it. But except for that special case, prelink -p is a good substitute. Cheers, Mark