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=-2.5 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 72DA7C06511 for ; Tue, 2 Jul 2019 15:51:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 48A4020989 for ; Tue, 2 Jul 2019 15:51:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="SrW1tDHk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727055AbfGBPvq (ORCPT ); Tue, 2 Jul 2019 11:51:46 -0400 Received: from mail-qk1-f196.google.com ([209.85.222.196]:39097 "EHLO mail-qk1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726861AbfGBPvp (ORCPT ); Tue, 2 Jul 2019 11:51:45 -0400 Received: by mail-qk1-f196.google.com with SMTP id i125so14495032qkd.6 for ; Tue, 02 Jul 2019 08:51:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=mIWxYRc22+ugt+mOFaGt8B3CI/ZTBy55XFxSUnaUbpU=; b=SrW1tDHkt1EmmC9FfGAf47t51HUD1VVyjv7HBLv1c7zUOIYjubM3QYyqpWV+SkbZ39 j7Ug9Rd5u6/FyzY3AOmMDb96rUxwOV7f/biUn+PUYZqVfSx2njY1W5/mcVge4GqefvwC C1FvnBvaB98dIQFwuveo/ODlJ91YF6zIu3y7g+UaOxwdYmhRuFqSogF6Msb0nv8TfVRt eNAFa9I6CK0QpkVe17VGKcajWFagv8g/pkx4Ph9dyjWGefaJUuMNrTFmOCEY8MXuXyii Z1UO18knRVpq2AVdi9AM+eLsylqHgN39s8dMiHtKqBqVux1nTfTaZosECmizLV7LD6sF yTCg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=mIWxYRc22+ugt+mOFaGt8B3CI/ZTBy55XFxSUnaUbpU=; b=mJ7Yf0k7wxMO0jZyYinz7Ni83xuRf3OBDuN6/3/2Hc0p5Eer4sR+kYc3OfdeHlsRjV yZCCBUzEfwKMo0YNGeuZY02u1sZvj2zDfJFubX1gZJM35hakvVFSqkj5poAjgKzHq/Z3 mg0duHQ2C7qZk2AYOTMnopVwX5g4ax3vTp1UeFClYPoEqiKxfwk3bIwCVwhUX2/CJD4n zlLkx+PUviLfPyWto7edbb4CU6ILJOOHRp/Qxl41IViyXQ9H7QZx7xhefm0XlN3oevYM Vbfaw2ZJoVdjc8sJfnPYGrqe43INVZpgJnnZxEv6MEAb6W8kzVBBUsntc/NAXIy76GZ+ NCLQ== X-Gm-Message-State: APjAAAURyY493G3p32MiOXOMzcUZg0AUrq/ny4Zfg3DcQYNHqdgPMli9 algqGBqLxvoQIBqnNxE6Juw= X-Google-Smtp-Source: APXvYqwhkQLuFLGmhGuf9I43Lq7LpibYaGe0QFBn0FZo9zBkZy5J6FNAtylba/DPo/zrKoc2VPQcyQ== X-Received: by 2002:a37:9a96:: with SMTP id c144mr24614572qke.468.1562082704405; Tue, 02 Jul 2019 08:51:44 -0700 (PDT) Received: from quaco.ghostprotocols.net ([179.97.35.11]) by smtp.gmail.com with ESMTPSA id s44sm8346934qtc.8.2019.07.02.08.51.43 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Tue, 02 Jul 2019 08:51:44 -0700 (PDT) From: Arnaldo Carvalho de Melo X-Google-Original-From: Arnaldo Carvalho de Melo Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id BBEA241153; Tue, 2 Jul 2019 12:51:38 -0300 (-03) Date: Tue, 2 Jul 2019 12:51:38 -0300 To: Jiri Olsa Cc: Jin Yao , jolsa@kernel.org, peterz@infradead.org, mingo@redhat.com, alexander.shishkin@linux.intel.com, Linux-kernel@vger.kernel.org, ak@linux.intel.com, kan.liang@intel.com, yao.jin@intel.com Subject: Re: [PATCH v6 0/7] perf diff: diff cycles at basic block level Message-ID: <20190702155138.GD15462@kernel.org> References: <1561713784-30533-1-git-send-email-yao.jin@linux.intel.com> <20190628080255.GA3427@krava> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190628080255.GA3427@krava> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.11.3 (2019-02-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Fri, Jun 28, 2019 at 10:02:55AM +0200, Jiri Olsa escreveu: > On Fri, Jun 28, 2019 at 05:22:57PM +0800, Jin Yao wrote: > > In some cases small changes in hot loops can show big differences. > > But it's difficult to identify these differences. > > > > perf diff currently can only diff symbols (functions). We can also expand > > it to diff cycles of individual programs blocks as reported by timed LBR. > > This would allow to identify changes in specific code accurately. > > > > With this patch set, for example, > > > > $ perf record -b ./div > > $ perf record -b ./div > > $ perf diff -c cycles > > > > # Event 'cycles' > > # > > # Baseline [Program Block Range] Cycles Diff Shared Object Symbol > > # ........ ...................................................................... ................ .................................. > > # > > 48.75% [div.c:42 -> div.c:45] 147 div [.] main > > 48.75% [div.c:31 -> div.c:40] 4 div [.] main > > 48.75% [div.c:40 -> div.c:40] 0 div [.] main > > 48.75% [div.c:42 -> div.c:42] 0 div [.] main > > 48.75% [div.c:42 -> div.c:44] 0 div [.] main > > 19.02% [random_r.c:357 -> random_r.c:360] 0 libc-2.23.so [.] __random_r > Reviewed-by: Jiri Olsa Looks really nice, thanks, applied. - Arnaldo