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=-5.4 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,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 556E9C432BE for ; Fri, 30 Jul 2021 03:16:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4078C604DC for ; Fri, 30 Jul 2021 03:16:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234986AbhG3DQT (ORCPT ); Thu, 29 Jul 2021 23:16:19 -0400 Received: from szxga03-in.huawei.com ([45.249.212.189]:12333 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229971AbhG3DQO (ORCPT ); Thu, 29 Jul 2021 23:16:14 -0400 Received: from dggemv703-chm.china.huawei.com (unknown [172.30.72.54]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4GbXVN0SRnz7ylK; Fri, 30 Jul 2021 11:11:24 +0800 (CST) Received: from dggpeml500013.china.huawei.com (7.185.36.41) by dggemv703-chm.china.huawei.com (10.3.19.46) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Fri, 30 Jul 2021 11:16:09 +0800 Received: from [10.174.187.161] (10.174.187.161) by dggpeml500013.china.huawei.com (7.185.36.41) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2176.2; Fri, 30 Jul 2021 11:16:08 +0800 Subject: Re: [PATCH v14 00/11] KVM: x86/pmu: Guest Last Branch Recording Enabling To: , , References: <20210201051039.255478-1-like.xu@linux.intel.com> <6102A1A5.90901@huawei.com> CC: , , , , , , , , , , , , "Fangyi (Eric)" , Xiexiangyou From: Liuxiangdong Message-ID: <61036EEC.4020006@huawei.com> Date: Fri, 30 Jul 2021 11:15:56 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 MIME-Version: 1.0 In-Reply-To: <6102A1A5.90901@huawei.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.187.161] X-ClientProxiedBy: dggeme720-chm.china.huawei.com (10.1.199.116) To dggpeml500013.china.huawei.com (7.185.36.41) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, like. Does it have requirement on CPU if we want to use LBR in Guest? I have tried linux-5.14-rc3 on different CPUs. And I can use lbr on Haswell, Broadwell, skylake and icelake, but I cannot use lbr on IvyBridge. Thanks! On 2021/7/29 20:40, Liuxiangdong wrote: > Hi, like. > > This patch set has been merged in 5.12 kernel tree so we can use LBR > in Guest. > Does it have requirement on CPU? > I can use lbr in guest on skylake and icelake, but cannot on IvyBridge. > > I can see lbr formats(000011b) in perf_capabilities msr(0x345), but > there is still > error when I try. > > $ perf record -b > Error: > cycles: PMU Hardware doesn't support sampling/overflow-interrupts. Try > 'perf stat' > > Host CPU: > Architecture: x86_64 > CPU op-mode(s): 32-bit, 64-bit > Byte Order: Little Endian > Address sizes: 46 bits physical, 48 bits virtual > CPU(s): 24 > On-line CPU(s) list: 0-23 > Thread(s) per core: 2 > Core(s) per socket: 6 > Socket(s): 2 > NUMA node(s): 2 > Vendor ID: GenuineIntel > CPU family: 6 > Model: 62 > Model name: Intel(R) Xeon(R) CPU E5-2620 v2 @ > 2.10GHz > Stepping: 4 > > > Thanks! > Xiangdong Liu