From patchwork Mon May 29 11:49:47 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Wu, Fei" X-Patchwork-Id: 13258462 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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 63155C77B7E for ; Mon, 29 May 2023 11:50:49 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1q3bMs-00054A-FT; Mon, 29 May 2023 07:48:54 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1q3bMm-000523-Ew for qemu-devel@nongnu.org; Mon, 29 May 2023 07:48:48 -0400 Received: from mga03.intel.com ([134.134.136.65]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1q3bMk-0004Vb-HP for qemu-devel@nongnu.org; Mon, 29 May 2023 07:48:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1685360926; x=1716896926; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=GxUbS8UIGU9fRc7ViV5mnBxcf9bwR8+T1stIrLTct80=; b=B316EO9ovsiptPHPsNoQT8DGgaDmmqLuqgKzNUptABFmj1CuA7BRuq6D GQ2UK45o7PxgS389OA2aI4sDpjktZQ818FxpRXIHka7TygI9dYUUfV8rW tkMO9t8kBNhp5zSQ3GcTkFxRyQJ1FnWMVxRUfVZF6ZxmHocvU+O1RJNfs zIhFYmtfOcczy+ui2CDMj83J9qZqxJBGNBOQ7xpj3Ne+C1Pu8HolRLmIn sxxcGWbXbvDUKLP6XJiKl6MQUJ2nCF4dZbaE9QnGM1EThKQbSzUgMte6N PR4hdi0XdfSjIiUFejzcfX9X5pUDtI9UDjN4bO6wY0JFTjHd6quENouZ4 A==; X-IronPort-AV: E=McAfee;i="6600,9927,10724"; a="357939710" X-IronPort-AV: E=Sophos;i="6.00,201,1681196400"; d="scan'208";a="357939710" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 May 2023 04:48:39 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10724"; a="683554511" X-IronPort-AV: E=Sophos;i="6.00,201,1681196400"; d="scan'208";a="683554511" Received: from wufei-optiplex-7090.sh.intel.com ([10.238.200.247]) by orsmga006.jf.intel.com with ESMTP; 29 May 2023 04:48:32 -0700 From: Fei Wu To: richard.henderson@linaro.org, alex.bennee@linaro.org, qemu-devel@nongnu.org Cc: Fei Wu , Paolo Bonzini Subject: [PATCH v13 10/10] docs: add tb-stats how to Date: Mon, 29 May 2023 19:49:47 +0800 Message-Id: <20230529114947.2123652-11-fei2.wu@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230529114947.2123652-1-fei2.wu@intel.com> References: <20230529114947.2123652-1-fei2.wu@intel.com> MIME-Version: 1.0 Received-SPF: pass client-ip=134.134.136.65; envelope-from=fei2.wu@intel.com; helo=mga03.intel.com X-Spam_score_int: -45 X-Spam_score: -4.6 X-Spam_bar: ---- X-Spam_report: (-4.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.16, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Signed-off-by: Fei Wu --- docs/devel/tcg-tbstats.rst | 129 +++++++++++++++++++++++++++++++++++++ 1 file changed, 129 insertions(+) create mode 100644 docs/devel/tcg-tbstats.rst diff --git a/docs/devel/tcg-tbstats.rst b/docs/devel/tcg-tbstats.rst new file mode 100644 index 0000000000..bfba222e96 --- /dev/null +++ b/docs/devel/tcg-tbstats.rst @@ -0,0 +1,129 @@ +============ +TBStatistics +============ + +What is TBStatistics +==================== + +TBStatistics (tb_stats) is a tool to gather various internal information of TCG +during binary translation, this allows us to identify such as hottest TBs, +guest to host instruction translation ratio, number of spills during register +allocation and more. + + +How to use TBStatistics +======================= + +1. HMP interface +---------------- + +TBStatistics provides HMP interface, you can try the following examples after +connecting to the monitor. + +* First check the help info:: + + (qemu) help tb_stats + tb_stats command [stats_level] -- Control tb statistics collection:tb_stats (start|pause|stop|filter) [all|jit_stats|exec_stats] + + (qemu) help info tb-list + info tb-list [number sortedby] -- show a [number] translated blocks sorted by [sortedby]sortedby opts: hotness hg spills + + (qemu) help info tb + info tb id [flag1,flag2,...] -- show information about one translated block by id.dump flags can be used to set dump code level: out_asm in_asm op + +* Enable TBStatistics:: + + (qemu) tb_stats start all + (qemu) + +* Get interested TB list:: + + (qemu) info tb-list 2 + TB id:1 | phys:0x79bca0 virt:0xffffffff8059bca0 flags:0x01024001 0 inv/1 + | exec:1464084/0 guest inst cov:0.15% + | trans:1 ints: g:3 op:16 op_opt:15 spills:0 + | h/g (host bytes / guest insts): 64.000000 + | time to gen at 2.4GHz => code:607.08(ns) IR:250.83(ns) + + TB id:2 | phys:0x2adf0c virt:0xffffffff800adf0c flags:0x01024001 0 inv/1 + | exec:1033298/0 guest inst cov:0.28% + | trans:1 ints: g:8 op:35 op_opt:33 spills:0 + | h/g (host bytes / guest insts): 86.000000 + | time to gen at 2.4GHz => code:1429.58(ns) IR:545.42(ns) + +* Dive into the specific TB:: + + (qemu) info tb 1 op + ------------------------------ + + TB id:1 | phys:0x79bca0 virt:0xffffffff8059bca0 flags:0x01024001 7 inv/19 + | exec:2038349/0 guest inst cov:0.15% + | trans:19 ints: g:3 op:16 op_opt:15 spills:0 + | h/g (host bytes / guest insts): 64.000000 + | time to gen at 2.4GHz => code:133434.17(ns) IR:176988.33(ns) + + OP: + ld_i32 loc1,env,$0xfffffffffffffff0 + brcond_i32 loc1,$0x0,lt,$L0 + mov_i64 loc3,$0x7f3c70b3a4e0 + call inc_exec_freq,$0x1,$0,loc3 + + ---- ffffffff8059bca0 0000000000006422 + add_i64 loc5,x2/sp,$0x8 + qemu_ld_i64 x8/s0,loc5,un+leq,1 + + ---- ffffffff8059bca2 0000000000000000 + add_i64 x2/sp,x2/sp,$0x10 + + ---- ffffffff8059bca4 0000000000000000 + mov_i64 pc,x1/ra + and_i64 pc,pc,$0xfffffffffffffffe + call lookup_tb_ptr,$0x6,$1,tmp9,env + goto_ptr tmp9 + set_label $L0 + exit_tb $0x7f3e887a8043 + + ------------------------------ + +* Stop TBStatistics after investigation, this will disable TBStatistics completely.:: + + (qemu) tb_stats stop + (qemu) + +* Alternatively, TBStatistics can be paused, the previous collected TBStatistics + are not cleared but there is no TBStatistics recorded for new TBs.:: + + (qemu) tb_stats pause + (qemu) + +* Definitely, TBStatistics can be restarted for another round of investigation.:: + + (qemu) tb_stats start all + (qemu) + + +2. Dump at exit +--------------- + +New command line options have been added to enable dump TB information at exit::: + + -d tb_stats[[,level=(+all+jit+exec+time)][,dump_limit=]] + +e.g. starting qemu like this::: + + -d tb_stats,dump_limit=2 + +Qemu prints the following at exit::: + + QEMU: Terminated + TB id:1 | phys:0x61be02 virt:0xffffffff8041be02 flags:0x01024001 0 inv/1 + | exec:72739176/0 guest inst cov:20.22% + | trans:1 ints: g:9 op:35 op_opt:33 spills:0 + | h/g (host bytes / guest insts): 51.555557 + | time to gen at 2.4GHz => code:1065.42(ns) IR:554.17(ns) + + TB id:2 | phys:0x61bc66 virt:0xffffffff8041bc66 flags:0x01024001 0 inv/1 + | exec:25069507/0 guest inst cov:0.77% + | trans:1 ints: g:1 op:15 op_opt:14 spills:0 + | h/g (host bytes / guest insts): 128.000000 + | time to gen at 2.4GHz => code:312.50(ns) IR:152.08(ns)