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=-2.7 required=3.0 tests=DATE_IN_FUTURE_06_12, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 7AACAC43613 for ; Thu, 20 Jun 2019 06:47:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4FD70206B7 for ; Thu, 20 Jun 2019 06:47:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730671AbfFTGrM (ORCPT ); Thu, 20 Jun 2019 02:47:12 -0400 Received: from mga18.intel.com ([134.134.136.126]:58599 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730267AbfFTGrM (ORCPT ); Thu, 20 Jun 2019 02:47:12 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 19 Jun 2019 23:47:11 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.63,395,1557212400"; d="scan'208";a="160573373" Received: from skl.sh.intel.com ([10.239.159.132]) by fmsmga008.fm.intel.com with ESMTP; 19 Jun 2019 23:47:08 -0700 From: Jin Yao To: acme@kernel.org, jolsa@kernel.org, peterz@infradead.org, mingo@redhat.com, alexander.shishkin@linux.intel.com Cc: Linux-kernel@vger.kernel.org, ak@linux.intel.com, kan.liang@intel.com, yao.jin@intel.com, Jin Yao Subject: [PATCH v4 0/7] perf diff: diff cycles at basic block level Date: Thu, 20 Jun 2019 22:36:35 +0800 Message-Id: <1561041402-29444-1-git-send-email-yao.jin@linux.intel.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 19.02% [random_r.c:357 -> random_r.c:373] 0 libc-2.23.so [.] __random_r 19.02% [random_r.c:357 -> random_r.c:376] 0 libc-2.23.so [.] __random_r 19.02% [random_r.c:357 -> random_r.c:380] 0 libc-2.23.so [.] __random_r 19.02% [random_r.c:357 -> random_r.c:392] 0 libc-2.23.so [.] __random_r 16.17% [random.c:288 -> random.c:291] 0 libc-2.23.so [.] __random 16.17% [random.c:288 -> random.c:291] 0 libc-2.23.so [.] __random 16.17% [random.c:288 -> random.c:295] 0 libc-2.23.so [.] __random 16.17% [random.c:288 -> random.c:297] 0 libc-2.23.so [.] __random 16.17% [random.c:291 -> random.c:291] 0 libc-2.23.so [.] __random 16.17% [random.c:293 -> random.c:293] 0 libc-2.23.so [.] __random 8.21% [div.c:22 -> div.c:22] 148 div [.] compute_flag 8.21% [div.c:22 -> div.c:25] 0 div [.] compute_flag 8.21% [div.c:27 -> div.c:28] 0 div [.] compute_flag 5.52% [rand.c:26 -> rand.c:27] 0 libc-2.23.so [.] rand 5.52% [rand.c:26 -> rand.c:28] 0 libc-2.23.so [.] rand 2.27% [rand@plt+0 -> rand@plt+0] 0 div [.] rand@plt 0.01% [entry_64.S:694 -> entry_64.S:694] 16 [kernel.vmlinux] [k] native_irq_return_iret 0.00% [fair.c:7676 -> fair.c:7665] 162 [kernel.vmlinux] [k] update_blocked_averages '[Program Block Range]' indicates the range of program basic block (start -> end). If we can find the source line it prints the source line otherwise it prints the symbol+offset instead. v4: --- Use source lines or symbol+offset to indicate the basic block. Changed patches: perf diff: Print the basic block cycles diff perf diff: Documentation -c cycles option v3: --- In v3, the major change is to move most of block stuffs from 'struct hist_entry' to new structure 'struct block_hist' and update the code accordingly. But we still have to keep the block_info in 'struct hist_entry' since we need to compare by block info when inserting new entry to hists. Others are minor changes, such as abs() -> labs(), removing duplicated ops and etc. Changed patches: perf diff: Use hists to manage basic blocks per symbol perf diff: Link same basic blocks among different data perf diff: Print the basic block cycles diff v2: --- Keep standard perf diff format. Following is the v1 output. # perf diff --basic-block # Cycles diff Basic block (start:end) # ........... ....................... # -208 hrtimer_interrupt (30b9e0:30ba42) -157 update_blocked_averages (2bf9f2:2bfa63) -126 interrupt_entry (c00880:c0093a) -86 hrtimer_interrupt (30bb29:30bb32) -74 hrtimer_interrupt (30ba65:30bac4) -56 update_blocked_averages (2bf980:2bf9d3) 48 update_blocked_averages (2bf934:2bf942) -35 native_write_msr (267900:26790b) 26 native_irq_return_iret (c00a27:c00a27) 22 rcu_check_callbacks (2febb6:2febdc) -21 __hrtimer_run_queues (30b220:30b2a3) 19 pvclock_gtod_notify (14ba0:14c1b) -18 task_tick_fair (2c5d29:2c5d41) Jin Yao (7): perf util: Create block_info structure perf util: Add block_info in hist_entry perf diff: Check if all data files with branch stacks perf diff: Use hists to manage basic blocks per symbol perf diff: Link same basic blocks among different data perf diff: Print the basic block cycles diff perf diff: Documentation -c cycles option tools/perf/Documentation/perf-diff.txt | 17 +- tools/perf/builtin-diff.c | 404 ++++++++++++++++++++++++++++++++- tools/perf/ui/stdio/hist.c | 27 +++ tools/perf/util/hist.c | 40 +++- tools/perf/util/hist.h | 9 + tools/perf/util/sort.h | 13 ++ tools/perf/util/srcline.c | 4 +- tools/perf/util/symbol.c | 22 ++ tools/perf/util/symbol.h | 23 ++ tools/perf/util/symbol_conf.h | 4 +- 10 files changed, 551 insertions(+), 12 deletions(-) -- 2.7.4