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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 4DB18C5DF60 for ; Thu, 7 Nov 2019 19:03:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2439B2085B for ; Thu, 7 Nov 2019 19:03:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573153404; bh=7KI1VZDJfay6DUglYPSy+O3w4iEFOv5wwyfb8yRV5TM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=O1gSlp7Frx/otrR8Ywm6qnxTU3Gmv1DIiSVqHn8Gb388SnjLlLJDdsL+YGtr/RXYD Ogxhfad87Nj3d25twjTVvW15e6sBjs0AzTaI5xpetC+fOQAHg0jCMOsRnmGAeX/uLL sVH+D0LOIbOVWmIv6Xrjy2RpAjl5GEl4b6qh862A= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729532AbfKGTDX (ORCPT ); Thu, 7 Nov 2019 14:03:23 -0500 Received: from mail.kernel.org ([198.145.29.99]:42424 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725906AbfKGTDW (ORCPT ); Thu, 7 Nov 2019 14:03:22 -0500 Received: from quaco.ghostprotocols.net (179-240-172-58.3g.claro.net.br [179.240.172.58]) (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 C648621D6C; Thu, 7 Nov 2019 19:03:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573153401; bh=7KI1VZDJfay6DUglYPSy+O3w4iEFOv5wwyfb8yRV5TM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rJGoLht7WPCNhH3OV+W7/NGLVT9ictw6H+ph99wvWAAuFyVOf4ePt7dfermlP/Lxk EZSCnJ/DrYTUGwKmKXzyg3A6nbDQ6q3GsQB7aDiJiUFYS+89zXO/LN8Yl5j+Mwr9MN bLJhiLv2OUJsNu48fqUnLYzjjl19Dbs+KJrvAfcE= From: Arnaldo Carvalho de Melo To: Ingo Molnar , Thomas Gleixner Cc: Jiri Olsa , Namhyung Kim , Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Masami Hiramatsu , Arnaldo Carvalho de Melo , Arnaldo Carvalho de Melo , Jiri Olsa Subject: [PATCH 20/63] perf probe: Fix to probe a function which has no entry pc Date: Thu, 7 Nov 2019 15:59:28 -0300 Message-Id: <20191107190011.23924-21-acme@kernel.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20191107190011.23924-1-acme@kernel.org> References: <20191107190011.23924-1-acme@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Masami Hiramatsu Fix 'perf probe' to probe a function which has no entry pc or low pc but only has ranges attribute. probe_point_search_cb() uses dwarf_entrypc() to get the probe address, but that doesn't work for the function DIE which has only ranges attribute. Use die_entrypc() instead. Without this fix: # perf probe -k ../build-x86_64/vmlinux -D clear_tasks_mm_cpumask:0 Probe point 'clear_tasks_mm_cpumask' not found. Error: Failed to add events. With this: # perf probe -k ../build-x86_64/vmlinux -D clear_tasks_mm_cpumask:0 p:probe/clear_tasks_mm_cpumask clear_tasks_mm_cpumask+0 Committer testing: Before: [root@quaco ~]# perf probe clear_tasks_mm_cpumask:0 Probe point 'clear_tasks_mm_cpumask' not found. Error: Failed to add events. [root@quaco ~]# After: [root@quaco ~]# perf probe clear_tasks_mm_cpumask:0 Added new event: probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask) You can now use it in all perf tools, such as: perf record -e probe:clear_tasks_mm_cpumask -aR sleep 1 [root@quaco ~]# Using it with 'perf trace': [root@quaco ~]# perf trace -e probe:clear_tasks_mm_cpumask Doesn't seem to be used in x86_64: $ find . -name "*.c" | xargs grep clear_tasks_mm_cpumask ./kernel/cpu.c: * clear_tasks_mm_cpumask - Safely clear tasks' mm_cpumask for a CPU ./kernel/cpu.c:void clear_tasks_mm_cpumask(int cpu) ./arch/xtensa/kernel/smp.c: clear_tasks_mm_cpumask(cpu); ./arch/csky/kernel/smp.c: clear_tasks_mm_cpumask(cpu); ./arch/sh/kernel/smp.c: clear_tasks_mm_cpumask(cpu); ./arch/arm/kernel/smp.c: clear_tasks_mm_cpumask(cpu); ./arch/powerpc/mm/nohash/mmu_context.c: clear_tasks_mm_cpumask(cpu); $ find . -name "*.h" | xargs grep clear_tasks_mm_cpumask ./include/linux/cpu.h:void clear_tasks_mm_cpumask(int cpu); $ find . -name "*.S" | xargs grep clear_tasks_mm_cpumask $ Fixes: e1ecbbc3fa83 ("perf probe: Fix to handle optimized not-inlined functions") Reported-by: Arnaldo Carvalho de Melo Tested-by: Arnaldo Carvalho de Melo Signed-off-by: Masami Hiramatsu Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lore.kernel.org/lkml/157199319438.8075.4695576954550638618.stgit@devnote2 Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/probe-finder.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c index 2b6513e5725c..71633f55f045 100644 --- a/tools/perf/util/probe-finder.c +++ b/tools/perf/util/probe-finder.c @@ -982,7 +982,7 @@ static int probe_point_search_cb(Dwarf_Die *sp_die, void *data) param->retval = find_probe_point_by_line(pf); } else if (die_is_func_instance(sp_die)) { /* Instances always have the entry address */ - dwarf_entrypc(sp_die, &pf->addr); + die_entrypc(sp_die, &pf->addr); /* But in some case the entry address is 0 */ if (pf->addr == 0) { pr_debug("%s has no entry PC. Skipped\n", -- 2.21.0