Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752617Ab0FCSGi (ORCPT ); Thu, 3 Jun 2010 14:06:38 -0400 Received: from casper.infradead.org ([85.118.1.10]:48952 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750843Ab0FCSGh (ORCPT ); Thu, 3 Jun 2010 14:06:37 -0400 Date: Thu, 3 Jun 2010 15:06:13 -0300 From: Arnaldo Carvalho de Melo To: Stephane Eranian Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, mingo@elte.hu, paulus@samba.org, davem@davemloft.net, fweisbec@gmail.com, perfmon2-devel@lists.sf.net, eranian@gmail.com, tzanussi@gmail.com Subject: Re: how to use perf annotate on the kernel Message-ID: <20100603180613.GA10469@ghostprotocols.net> References: <20100603175445.GC8928@ghostprotocols.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100603175445.GC8928@ghostprotocols.net> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.5.20 (2009-08-17) X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3075 Lines: 62 Em Thu, Jun 03, 2010 at 02:54:45PM -0300, Arnaldo Carvalho de Melo escreveu: > Em Thu, Jun 03, 2010 at 07:23:02PM +0200, Stephane Eranian escreveu: > > # perf annotate (or annotate -d '[kernel.kallsyms]'?) > > Can't annotate __lock_acquire: No vmlinux file was found in the path > > > > # perf annotate -k vmlinux > > objdump: '[kernel.kallsyms]': No such file > > This looks like a bug in how it reports this problem, probably vmlinux > is not in the current directory, or it is but has a build-id that > doesn't matches the one in the perf.data file. > > But the message is wrong, should be like it is in the tui, for this same > situation: > > ui_helpline__puts("No vmlinux file found, can't " > "annotate with just a kallsyms file"); > > > Am I missing something here? > > If you don't specify it with --vmlinux/-k it will try to find it in one > of these places: > > vmlinux_path[vmlinux_path__nr_entries] = strdup("vmlinux"); > vmlinux_path[vmlinux_path__nr_entries] = strdup("/boot/vmlinux"); > snprintf(bf, sizeof(bf), "/boot/vmlinux-%s", uts.release); > vmlinux_path[vmlinux_path__nr_entries] = strdup(bf); > snprintf(bf, sizeof(bf), "/lib/modules/%s/build/vmlinux", uts.release); > vmlinux_path[vmlinux_path__nr_entries] = strdup(bf); > snprintf(bf, sizeof(bf), "/usr/lib/debug/lib/modules/%s/vmlinux", > uts.release); > vmlinux_path[vmlinux_path__nr_entries] = strdup(bf); > > It also now looks at /sys/kernel/notes, gets the build-id, and looks up > in the build-id cache. For instance, here using -vvv I get: [root@emilia ~]# perf annotate -vvv memcpy > /dev/null build id event received for [kernel.kallsyms]: 310920b54cbbf242dbfa09052f652806d2c73821 build id event received for /lib64/libtinfo.so.5.7: cd9da7b5b1fcb25ee6b3762bb9fe62f782590fd5 Looking at the vmlinux_path (6 entries long) No build_id in /root/.debug/.build-id/31/0920b54cbbf242dbfa09052f652806d2c73821, ignoring it No build_id in vmlinux, ignoring it No build_id in /boot/vmlinux, ignoring it No build_id in /boot/vmlinux-2.6.35-rc1, ignoring it Using /lib/modules/2.6.35-rc1/build/vmlinux for symbols hist_entry__inc_addr_samples: ip=0xffffffff811ea69e 0xffffffff811ea690 memcpy: period++ [ip: 0xffffffff811ea69e, 0xe] => 1 hist_entry__annotate: filename=/lib/modules/2.6.35-rc1/build/vmlinux, sym=memcpy, start=0xffffffff811ea690, end=0xffffffff811ea730 annotating [0x187e770] /lib/modules/2.6.35-rc1/build/vmlinux : [0x19b1f70] memcpy Executing: objdump --start-address=0xffffffff811ea690 --stop-address=0xffffffff811ea730 -dS /lib/modules/2.6.35-rc1/build/vmlinux|grep -v /lib/modules/2.6.35-rc1/build/vmlinux|expand [root@emilia ~]# I'm removing all vmlinux from the path so that I can reproduce what you see. - Arnaldo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/