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 D3F1AC4332F for ; Fri, 21 Oct 2022 07:38:04 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 161F58E0002; Fri, 21 Oct 2022 03:38:04 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 112278E0001; Fri, 21 Oct 2022 03:38:04 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id F1C0A8E0002; Fri, 21 Oct 2022 03:38:03 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id E04158E0001 for ; Fri, 21 Oct 2022 03:38:03 -0400 (EDT) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id AAA7912053B for ; Fri, 21 Oct 2022 07:38:03 +0000 (UTC) X-FDA: 80044152846.01.430FA4E Received: from mail-yb1-f181.google.com (mail-yb1-f181.google.com [209.85.219.181]) by imf02.hostedemail.com (Postfix) with ESMTP id 52A4080008 for ; Fri, 21 Oct 2022 07:38:03 +0000 (UTC) Received: by mail-yb1-f181.google.com with SMTP id n130so2362638yba.10 for ; Fri, 21 Oct 2022 00:38:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=YqCI81aYTBUvq0AjF/BYw/CwZWDfTatRIRM86fy8mzM=; b=hdGApCLDmq0zk1404naN816WsPf7cus4RecqB5gWNPeMIwXuVT2JpTqOAePyNFo0Q+ +A7vMQhDqeCFfi6RbOgeeW1dRh4oUJvWP0hZnDs/KK+Nv7HoCDL7+y5jUnB24RrIxW1V l9Grn4St0VsHs99MbtHIi8V8+4PhGRywmpkMY5QpBoXmPWTZOrPflcxxw9Cddy0OkLXA 1H83ZHNUriu0YQIACgBzfbWOrYIhJ4nYjCzGVKWq6lY+RHeOyNcAEqr07B+mZpQ06BZz JUWPvoaYDWVI28Wb9OBW92L2zM729XBkw1zK4NjdriUn0h0Tp9lUzd5pmxDXhdbubX15 x9Ag== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=YqCI81aYTBUvq0AjF/BYw/CwZWDfTatRIRM86fy8mzM=; b=rjI7E6EtFVR9GScQ91ych+lF21wyUolO23frA3+hqYsF4rNpqCm0Q93RJJ3rHHUxGp JmsLH4TAbDv1/b5M84qBia4XaE2lPOQKJmW8yq2CJ25St7dkz4fHLjBu9Jp5ClZtda0k ZobqE/RLVe05Tw2VQCCQQr4w63w+fmIkP53yg2ThuYdW7PMvhz3S+6+9vQgyBbxol1sE W7EIBzapHn9C6CBvxUE+BWlA88/62lNagw8VGLmUWpIAoCjhb2e9FYvh2cP85997sCIy rtjnzPY/UvPt6QRohrHe0Dk1x8jm5PGvLpwjvfe9Ho1whJsD9sOTv4b7JmCDJNA4FEqj NbYQ== X-Gm-Message-State: ACrzQf2FoicK9YZOZI0p4/pRVu0My9GTB7wyLytUNXIhj9eyYg6skZ7y igMGCTsc3tuoMIqOiVe4dOCchvzuzj2G0bttTWo4qQ== X-Google-Smtp-Source: AMsMyM62GSx0NWUinN6ObtQibLc5Ih1zlGVGyMCuv7Iu8ly2udUc3uKngmrdcVX2ldvl3SdCr2LW4qra3FYqJuzBJNY= X-Received: by 2002:a25:7b42:0:b0:6ca:1d03:2254 with SMTP id w63-20020a257b42000000b006ca1d032254mr8096145ybc.584.1666337882424; Fri, 21 Oct 2022 00:38:02 -0700 (PDT) MIME-Version: 1.0 References: <20220915150417.722975-19-glider@google.com> <20221019173620.10167-1-youling257@gmail.com> In-Reply-To: From: Marco Elver Date: Fri, 21 Oct 2022 00:37:26 -0700 Message-ID: Subject: Re: [PATCH v7 18/43] instrumented.h: add KMSAN support To: youling 257 Cc: Alexander Potapenko , 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 Content-Type: text/plain; charset="UTF-8" ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1666337883; a=rsa-sha256; cv=none; b=6IvAE+Lb+/DuctTmbV9XBn6vodOKxMXBStUlyeB0shP/Z9iBLdxVJgHNnilMWWfW96PoMG C4tvEiFmSp22sxqR8/e0b+VzC9MOrLhuMVl3lBLRIHqL1D8315DtrGDEpDqbp8Bv6qF7RI p9Xn31YGy+EF91YOs5gOS1lGB6D69vs= ARC-Authentication-Results: i=1; imf02.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=hdGApCLD; spf=pass (imf02.hostedemail.com: domain of elver@google.com designates 209.85.219.181 as permitted sender) smtp.mailfrom=elver@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1666337883; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=YqCI81aYTBUvq0AjF/BYw/CwZWDfTatRIRM86fy8mzM=; b=t66TfSyYJ5M/m4CaLiGg2SLY9yzqLISn1/TlyjciuQlAcQTAOHSgJ+ZSHYmujJhiDS1rct uNHMERr5349Z9t19wASVIpBHODOnxUxFL4GrZZ5jn5IJvLC+Cq1WTDEz9mpy9++OoKw7NR X/t0/NNiQuE1wRKib3cMai6tuePUW3U= X-Stat-Signature: if8p1sc14z7agjumbabpypyyjkc1tdh9 X-Rspamd-Queue-Id: 52A4080008 Authentication-Results: imf02.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=hdGApCLD; spf=pass (imf02.hostedemail.com: domain of elver@google.com designates 209.85.219.181 as permitted sender) smtp.mailfrom=elver@google.com; dmarc=pass (policy=reject) header.from=google.com X-Rspam-User: X-Rspamd-Server: rspam01 X-HE-Tag: 1666337883-769323 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 Thu, 20 Oct 2022 at 23:39, youling 257 wrote: > > PerfTop: 8253 irqs/sec kernel:75.3% exact: 100.0% lost: 0/0 drop: > 0/17899 [4000Hz cycles], (all, 8 CPUs) > --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- > > 14.87% [kernel] [k] 0xffffffff941d1f37 > 6.71% [kernel] [k] 0xffffffff942016cf > > what is 0xffffffff941d1f37? You need to build with debug symbols: CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y Then it'll show function names. > 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 kernel > > functions consume most CPU cycles. I would suggest you compare both > > kernels, and see if you can spot a function which uses more cycles% in > > the problematic kernel. > >