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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4515AFA373D for ; Fri, 21 Oct 2022 17:21:16 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A5DD28E0002; Fri, 21 Oct 2022 13:21:15 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A0E4C8E0001; Fri, 21 Oct 2022 13:21:15 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8AFCF8E0002; Fri, 21 Oct 2022 13:21:15 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 77ECA8E0001 for ; Fri, 21 Oct 2022 13:21:15 -0400 (EDT) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 45BFF1A0555 for ; Fri, 21 Oct 2022 17:21:15 +0000 (UTC) X-FDA: 80045622510.09.9E6537C Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf25.hostedemail.com (Postfix) with ESMTP id 99847A0027 for ; Fri, 21 Oct 2022 17:21:14 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id A122F61F1E; Fri, 21 Oct 2022 17:21:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 031EDC433D6; Fri, 21 Oct 2022 17:21:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1666372873; bh=OPwlLlEXlUzE6SL4e+b2hevX5SKArYC0yWnxgjj7sus=; h=Date:From:To:CC:Subject:In-Reply-To:References:From; b=sbc+CEwFVrdgV+3XX2gN5R7aeuG3yA9k2SFXrB8q1bEjcXoN9v9gOFU3SgcOCK8QX j+TzFP0Lfvmc6iQU2s81SsujeSt/Ib8TdzIvi0tG2zMXq21Q5LSCWUxTFc7iO5PQ/u gTcvkEJNDIEtjpzWUB+FmgqdSPdW0Ti1pWm1t3F0aE73wfIz43jN+2NoRzm6eJb3rB TEVl5NRncUIBHYHuxYWKe97bT9DHp4whnjKVnGkiwBwXqGqmu54/rLkfeP5TCZV9xP GQywwtek77jbiJ+ruHzyNcZYPIdozGCvOgdVjk4NilRO78fRqBPD91FSq3nl77p7zf s0Oe1XIahIygQ== Date: Fri, 21 Oct 2022 10:21:12 -0700 From: Kees Cook To: Alexander Potapenko , youling 257 CC: Marco Elver , Alexander Viro , Alexei Starovoitov , Andrew Morton , Andrey Konovalov , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Christoph Hellwig , Christoph Lameter , David Rientjes , Dmitry Vyukov , Eric Biggers , Eric Dumazet , Greg Kroah-Hartman , Herbert Xu , Ilya Leoshkevich , Ingo Molnar , Jens Axboe , Joonsoo Kim , Kees Cook , Mark Rutland , Matthew Wilcox , "Michael S. Tsirkin" , Pekka Enberg , Peter Zijlstra , Petr Mladek , Stephen Rothwell , Steven Rostedt , Thomas Gleixner , Vasily Gorbik , Vegard Nossum , Vlastimil Babka , kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v7 18/43] instrumented.h: add KMSAN support User-Agent: K-9 Mail for Android In-Reply-To: References: <20220915150417.722975-19-glider@google.com> <20221019173620.10167-1-youling257@gmail.com> Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1666372874; a=rsa-sha256; cv=none; b=ywJXIFMIvcXl9PTJ/usb3Nak9AVExt8XEQ9OZACCZsHwOoJ9nKIWwgsNxkxxCQ6De5Fzdz ErhOhLd32TzaMflKHGt2gTeF7Dm//OgMi4sQQzc2vrTf1m5CRBKmU83n0hIQBj1n2qst0+ yL6pouYEi3CQC4l+ngxuG8ioWIl9itY= ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=sbc+CEwF; spf=pass (imf25.hostedemail.com: domain of kees@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=kees@kernel.org; dmarc=pass (policy=none) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1666372874; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=OdWOQBaqPtwH7WTxoM2zqstOKsGwBaRxBfceti0LzbU=; b=dd00KCwD6LzGh/75doEHi95rg1z+2+Pztp6VQUZQ8RAY28j5ytJ31npx9CTUwp3arvfsp2 eYFJT8tAhBsot3lLxvzliF6RcLbgRhiyLt3xp+RqTVu1z+rSWKGtgavM0X8qSrQLHmI669 24+LulKO1X6PFGtimp+YdSy4IGkxO2k= X-Stat-Signature: 8ubwto8aemp4f5xu6wcggrnrs9szyund X-Rspamd-Queue-Id: 99847A0027 Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=sbc+CEwF; spf=pass (imf25.hostedemail.com: domain of kees@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=kees@kernel.org; dmarc=pass (policy=none) header.from=kernel.org X-Rspam-User: X-Rspamd-Server: rspam01 X-HE-Tag: 1666372874-362952 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On October 21, 2022 10:02:05 AM PDT, Alexander Potapenko wrote: >On Fri, Oct 21, 2022 at 8:19 AM youling 257 wrot= e: > >> CONFIG_DEBUG_INFO=3Dy >> CONFIG_AS_HAS_NON_CONST_LEB128=3Dy >> # CONFIG_DEBUG_INFO_NONE is not set >> CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=3Dy >> # CONFIG_DEBUG_INFO_DWARF4 is not set >> # CONFIG_DEBUG_INFO_DWARF5 is not set >> # CONFIG_DEBUG_INFO_REDUCED is not set >> # CONFIG_DEBUG_INFO_COMPRESSED is not set >> # CONFIG_DEBUG_INFO_SPLIT is not set >> # CONFIG_DEBUG_INFO_BTF is not set >> # CONFIG_GDB_SCRIPTS is not set >> >> perf top still no function name=2E >> >Will it help if you disable CONFIG_RANDOMIZE_BASE? >(if it doesn't show the symbols, at least we'll be able to figure out the >offending function by running nm) Is KALLSYMS needed? > > >> >> 12=2E90% [kernel] [k] 0xffffffff833dfa64 >> 3=2E78% [kernel] [k] 0xffffffff8285b439 >> 3=2E61% [kernel] [k] 0xffffffff83370254 >> 2=2E32% [kernel] [k] 0xffffffff8337025b >> 1=2E88% bluetooth=2Edefault=2Eso [=2E] 0x000000000000d09d >> >> 2022-10-21 15:37 GMT+08:00, Marco Elver : >> > On Thu, 20 Oct 2022 at 23:39, youling 257 wr= ote: >> >> >> >> PerfTop: 8253 irqs/sec kernel:75=2E3% exact: 100=2E0% lost: 0/0= drop: >> >> 0/17899 [4000Hz cycles], (all, 8 CPUs) >> >> >> -----------------------------------------------------------------------= ---------------------------------------------------------------------------= ------------------------------------------------------------- >> >> >> >> 14=2E87% [kernel] [k] 0xffffffff941d1f37 >> >> 6=2E71% [kernel] [k] 0xffffffff942016cf >> >> >> >> what is 0xffffffff941d1f37? >> > >> > You need to build with debug symbols: >> > CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=3Dy >> > >> > Then it'll show function names=2E >> > >> >> 2022-10-21 14:16 GMT+08:00, Marco Elver : >> >> > On Thu, 20 Oct 2022 at 22:55, youling 257 >> wrote: >> >> >> >> >> >> How to use perf tool? >> >> > >> >> > The simplest would be to try just "perf top" - and see which kerne= l >> >> > functions consume most CPU cycles=2E I would suggest you compare b= oth >> >> > kernels, and see if you can spot a function which uses more cycles= % in >> >> > the problematic kernel=2E >> >> > >> > >> > > --=20 Kees Cook