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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3E9FCC433EF for ; Thu, 16 Dec 2021 13:54:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236970AbhLPNyP (ORCPT ); Thu, 16 Dec 2021 08:54:15 -0500 Received: from st43p00im-zteg10063401.me.com ([17.58.63.175]:38328 "EHLO st43p00im-zteg10063401.me.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237058AbhLPNyP (ORCPT ); Thu, 16 Dec 2021 08:54:15 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=icloud.com; s=1a1hai; t=1639662854; bh=hIwCA46n4X8DBGy4YUjX7M53fn8LLYnEOCVe4AB7nec=; h=From:Content-Type:Mime-Version:Subject:Date:To:Message-Id; b=v/ZWwVzxmItPqXHjulmDVIZ4/BnJKwdA1wbPqYAnfrjk6UGfPRI2Ilqf8kOS1yd8g VEs8qGl3HH85li7bRV0A4W15Qno56v2C+sI5TBvYRoqc2eZV5QXMfU6iIsMv0yWsIw XhttKVwfxwPXB9CqhhWaEdDaMbpGcknSB0HVea08Qv/94bKLfqbRAp1u8lmYEo0LKq 5yajEhyv6f+cafXuP7ACIXSHcgmjg1BiWtMmoOTtntkvImNMynZJHvr2XTDl8Ibd93 w06YaCypQj0U2X/0HK+E72+iGBzLza2rhWjArt2oOhyt3A7qmzAsGlZcwAwqSpkD8G M5exCZwdDYhgA== Received: from smtpclient.apple (cpe-66-24-82-52.stny.res.rr.com [66.24.82.52]) by st43p00im-zteg10063401.me.com (Postfix) with ESMTPSA id 495A74A05A6 for ; Thu, 16 Dec 2021 13:54:14 +0000 (UTC) From: Timothy Miller Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 (Mac OS X Mail 15.0 \(3693.40.0.1.81\)) Subject: Re: perf not showing me call graph for memcpy no matter what Date: Thu, 16 Dec 2021 08:54:12 -0500 References: <55BDE53A-EF97-4EF6-80C4-11821372A842@icloud.com> To: linux-perf-users@vger.kernel.org In-Reply-To: <55BDE53A-EF97-4EF6-80C4-11821372A842@icloud.com> Message-Id: X-Mailer: Apple Mail (2.3693.40.0.1.81) X-Proofpoint-Virus-Version: =?UTF-8?Q?vendor=3Dfsecure_engine=3D1.1.170-22c6f66c430a71ce266a39bfe25bc?= =?UTF-8?Q?2903e8d5c8f:6.0.425,18.0.790,17.11.62.513.0000000_definitions?= =?UTF-8?Q?=3D2021-12-16=5F04:2021-12-14=5F01,2021-12-16=5F04,2021-12-02?= =?UTF-8?Q?=5F01_signatures=3D0?= X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 spamscore=0 adultscore=0 mlxlogscore=829 phishscore=0 bulkscore=0 mlxscore=0 suspectscore=0 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2112160078 Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org Sorry about the duplicate. Majordomo kept throwing errors when I would = try to join or verify. It really didn=E2=80=99t like the email address I = tried to use before, so I assumed that it wasn=E2=80=99t going to accept = the post either. > On Dec 16, 2021, at 8:37 AM, Timothy Miller = wrote: >=20 > Hi, >=20 > I am doing some software profiling on an aarch64 system, and I=E2=80=99m= using the Linux perf tool. The problem I=E2=80=99m running into is that = =E2=80=9C__GI___memcpy_simd=E2=80=9D keeps showing up as the function = with the most CPU usage. >=20 > Unfortunately, no matter what I do, this function keeps showing up as = orphaned. That is, I cannot get a stack trace for it so I can find out = who is calling it. >=20 > I have tried using dwarf mode, but it always gets overloaded. >=20 > I have tried using lbr mode, but I get the following error: > Error: > PMU Hardware doesn't support sampling/overflow-interrupts. >=20 > I=E2=80=99ve rebuilt my application and all relevant libraries with = -no-omit-frame-pointer so that I could use the default frame pointer = mode. Unfortunately, I still can=E2=80=99t get a call graph for this = function. >=20 > I emailed the glibc mailing list about this, trying to find out how to = work around this problem, perhaps adding frame pointer to the assembly = implementation of memcpy. They suggested I try attaching a debugger, and = I=E2=80=99ve found that I can get stack traces just fine. They suggest = that I seem to be running into some kind of bug in perf.=20 >=20 > Any help/advice would be appreciated. >=20 > Thanks. >=20