Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752896Ab0AHLhO (ORCPT ); Fri, 8 Jan 2010 06:37:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751797Ab0AHLhN (ORCPT ); Fri, 8 Jan 2010 06:37:13 -0500 Received: from bombadil.infradead.org ([18.85.46.34]:60650 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750863Ab0AHLhM (ORCPT ); Fri, 8 Jan 2010 06:37:12 -0500 Date: Fri, 8 Jan 2010 09:36:57 -0200 From: Arnaldo Carvalho de Melo To: Jamie Iles Cc: linux-kernel@vger.kernel.org, Jamie Iles , Peter Zijlstra , Paul Mackerras Subject: Re: [PATCH] perf symbols: don't use modules or try vmlinux unless needed Message-ID: <20100108113657.GE12660@ghostprotocols.net> References: <1262600634-6628-1-git-send-email-jamie.iles@picochip.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1262600634-6628-1-git-send-email-jamie.iles@picochip.com> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.5.19 (2009-01-05) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.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: 2578 Lines: 52 Em Mon, Jan 04, 2010 at 10:23:54AM +0000, Jamie Iles escreveu: > Commit 75be6cf (perf symbols: Make symbol_conf global) does what it says > on the tin, but also initialises the member fields use_modules and > try_vmlinux_path to true rather than the 'false' value they would have > had when symbol_conf was static. > > When there is no vmlinux on the system and modules loaded, perf top will > not show any kernel symbols and perf report will only list raw IP's > rather than symbol names. Unloading the modules will allow perf to give > normal output. > > Restore previous behaviour by initialising these fields to false. James, I just tried using perf top here in such conditions: [root@ana ~]# strace -e open -o /tmp/perf.open.strace perf top ------------------------------------------------------------------------ PerfTop: 65 irqs/sec kernel:64.6% [1000Hz cycles], (all, 2 CPUs) ------------------------------------------------------------------------ samples pcnt function DSO _______ _____ __________________ _________________ 12.00 7.0% format_decode [kernel.kallsyms] 10.00 5.8% __strstr_ia32 /lib/libc-2.11.so 9.00 5.3% read_hpet [kernel.kallsyms] 7.00 4.1% module_get_kallsym [kernel.kallsyms] 5.00 2.9% vsnprintf [kernel.kallsyms] 5.00 2.9% __memchr /lib/libc-2.11.so /usr/lib/libgtk-x11-2.0.so.0.1800.5.#prelink#.aAFN89 was updated, restart the long running apps that use it! [root@ana ~]# grep vmlinux /tmp/perf.open.strace open("vmlinux", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory) open("/boot/vmlinux", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory) open("/boot/vmlinux-2.6.31.9-174.fc12.i686", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory) open("/lib/modules/2.6.31.9-174.fc12.i686/build/vmlinux", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory) open("/usr/lib/debug/lib/modules/2.6.31.9-174.fc12.i686/vmlinux", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory) And it is resolving the kernel symbols. Maybe some changes I made that aren't yet in Ingo's tree or upstream fixed it, can you please try after those patches are merged? - 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/