From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5E6F7C6786F for ; Tue, 30 Oct 2018 15:11:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 27BC920823 for ; Tue, 30 Oct 2018 15:11:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="U4O/CUN3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 27BC920823 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727583AbeJaAFd (ORCPT ); Tue, 30 Oct 2018 20:05:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:45024 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726903AbeJaAFd (ORCPT ); Tue, 30 Oct 2018 20:05:33 -0400 Received: from jouet.infradead.org (unknown [190.15.121.82]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id AED53204FD; Tue, 30 Oct 2018 15:11:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1540912301; bh=c5qZK/ylEs1KowBEgAkpI4GJ7m5Kt/PIxHrNGM5No0s=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=U4O/CUN3U1VlDx9f/pCdd5SZL9kn24nJ7t/PUPkHW97UJSPoSTS+VtPA/CGhPoAN9 cJZvvuK1gsBTF2qIXnVGKTeqjaPsq1WlJ8wTgk2J7+yyOQSGCrjTciYFOKGl0iQ0Np jPVViA9Hcpf7v/LogHz/IZN7/qX1tFuEFf0TRwpY= Received: by jouet.infradead.org (Postfix, from userid 1000) id 0FD64142C5F; Tue, 30 Oct 2018 12:11:38 -0300 (-03) Date: Tue, 30 Oct 2018 12:11:38 -0300 From: Arnaldo Carvalho de Melo To: leo.yan@linaro.org, Adrian Hunter Cc: Mathieu Poirier , Peter Zijlstra , Alexander Shishkin , Jiri Olsa , Namhyung Kim , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Coresight ML Subject: Re: [PATCH] perf cs-etm: Correct CPU mode for samples Message-ID: <20181030151137.GF23310@kernel.org> References: <1540883908-17018-1-git-send-email-leo.yan@linaro.org> <20181030143226.GA23310@kernel.org> <20181030150449.GB8344@leoy-ThinkPad-X240s> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181030150449.GB8344@leoy-ThinkPad-X240s> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Tue, Oct 30, 2018 at 11:04:49PM +0800, leo.yan@linaro.org escreveu: > Hi Arnaldo, > > On Tue, Oct 30, 2018 at 11:32:26AM -0300, Arnaldo Carvalho de Melo wrote: > > Em Tue, Oct 30, 2018 at 03:18:28PM +0800, Leo Yan escreveu: > > > Since commit 9042f5e3539e ("perf tools: Stop fallbacking to kallsyms > > > for vdso symbols lookup"), the kernel address cannot be properly parsed > > > to kernel symbol with command 'perf script -k vmlinux'. The reason is > > > CoreSight samples is always to set CPU mode as PERF_RECORD_MISC_USER, > > > thus it fails to find corresponding map/dso in below flows: > > > > > > process_sample_event() > > > `-> machine__resolve() > > > `-> thread__find_map(thread, sample->cpumode, sample->ip, al); > > > > > > In this flow it needs to pass argument 'sample->cpumode' to tell what's > > > the CPU mode, before it always passed PERF_RECORD_MISC_USER but without > > > any failure until the commit 9042f5e3539e ("perf tools: Stop fallbacking > > > to kallsyms for vdso symbols lookup") has been merged. The reason is > > > even with the wrong CPU mode the function thread__find_map() firstly > > > fails to find map but it will rollback to find kernel map for vdso > > > symbols lookup. In the latest code it has removed the fallback code, > > > thus if CPU mode is PERF_RECORD_MISC_USER then it cannot find map > > > anymore with kernel address. > > > > > > This patch is to correct samples CPU mode setting, it creates a new > > > helper function cs_etm__cpu_mode() to tell what's the CPU mode based on > > > the address with the info from machine structure; this patch has a bit > > > extension to check not only kernel and user mode, but also check for > > > host/guest and hypervisor mode. Finally this patch uses the function > > > in instruction and branch samples and also apply in cs_etm__mem_access() > > > for a minor polishing. > > > > Mathieu, can I have your Acked-by, please? Leo, thanks for acting so > > quickly on this one! > > Thanks for reivewing. Yeah, let's wait for Mathieu reviewing as well, > as I know he is travelling so might be delay a bit. I'm tentatively applying the patch, as this needs fixing ASAP, and I take that you have tested it and it cured the problem for you, so should be a good indication for the acceptance of the patch. We can always fix some detail later. > Just remind, we might need the similiar change for util/intel-pt.c and > util/intel-bts.c when generate samples, otherwise they might have the > same regression for kernel symbols. I am not the best person to change > these two files, but bring up this for attention. Right, I think Adrian is working on it, Adrian? > > Now processing coresight traces should be faster, less lookups :-) > > Thanks! - Arnaldo