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=-8.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL 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 89608C43387 for ; Wed, 2 Jan 2019 23:27:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4CEA32080A for ; Wed, 2 Jan 2019 23:27:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="vBMPfxa8" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729863AbfABX1J (ORCPT ); Wed, 2 Jan 2019 18:27:09 -0500 Received: from mail-it1-f195.google.com ([209.85.166.195]:38731 "EHLO mail-it1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727320AbfABX1J (ORCPT ); Wed, 2 Jan 2019 18:27:09 -0500 Received: by mail-it1-f195.google.com with SMTP id h65so40691882ith.3 for ; Wed, 02 Jan 2019 15:27:08 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=cxlb00yXd4iinTkVLhy1QF9aoqxxUYJBNn8i+UuGVXM=; b=vBMPfxa8lp64v4EVumWD8KiZugAg7LLOgO8c9mBLn/Xam0gGJ0BwNR2V0w8GlmDTlx WUOrAFGkDlIJ1B5ygQrETaySozK7ggOZzYG1nvy9D0sJ8kROC7fvvidyUXA3hw7UVu7L RG2KACDgRS9TRTOegbWD4rwKNCyYjDnmYQI/Iy3Z2qSsmWJaAcwLfj2m5epKcqbont7F EB/AyeSxT+PZxV3LYr0NWyi011ySgs2OlK4FpKotVNkG3Sr1hnZ2PMv6F6XQfqCsI7Yc HGS7zYxUrHgD7EPjFACHJXL996WQ50/rHKCjpHYbQx34s7ftkHPd/lm4lbYgjTOK1+Fq xdSw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=cxlb00yXd4iinTkVLhy1QF9aoqxxUYJBNn8i+UuGVXM=; b=rmZrv6o3BQzKTXzKgxwsDqHN1gKbuprTEFW3HiY/k3PKmQvZmuFLe8KTog6nkXOhO2 CEgJecmKt7o+Zv/RyLtJsbErvHGF16k2YChHbHhjWb3UlptTKJE2H1BehBAEAeeEczg/ xGRTTj5eDPhUDaHzk/ouqddI5P4UGU6TmULWi56G9Xih6t0mWbOHIxWOIYTut4qZW8wv V9uwU2VmyT3BIfkLLhmjAnTWQ2ScgOjo5w3HcmuBTfmMOXamDOwrp2WxgIIcRqRFuHMC KDxiAmU3fIj9a5e3zTd26vIwDyUuv6lsyYnXOEAf3IkChvcxWUjeQ7RYhD6v3gO9vlU3 4QqQ== X-Gm-Message-State: AA+aEWaGKv6obchFGK8eqtXs9hWBNRWMLY2FJC4yE4tspx49acXhNDHH yn78OyyVNNNWmBv6LSExSDr9ovMGbHnPyxoMKCfynbmREpM= X-Google-Smtp-Source: AFSGD/VZ1Dm0Hgjw1mbehr5Q0AQN7/wuBkgV3zXfsf+MOWyzTQXRlaiuA4sKZhNcK3aMspSbsW3ofb+bZRacTEQHfMk= X-Received: by 2002:a24:4a95:: with SMTP id k143mr28726948itb.77.1546471628031; Wed, 02 Jan 2019 15:27:08 -0800 (PST) MIME-Version: 1.0 References: <1545816338-1171-1-git-send-email-wei.w.wang@intel.com> <1545816338-1171-5-git-send-email-wei.w.wang@intel.com> In-Reply-To: <1545816338-1171-5-git-send-email-wei.w.wang@intel.com> From: Jim Mattson Date: Wed, 2 Jan 2019 15:26:56 -0800 Message-ID: Subject: Re: [PATCH v4 04/10] KVM/x86: intel_pmu_lbr_enable To: Wei Wang Cc: LKML , kvm list , Paolo Bonzini , Andi Kleen , Peter Zijlstra , Kan Liang , Ingo Molnar , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , like.xu@intel.com, Jann Horn , arei.gonglei@huawei.com Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 26, 2018 at 2:01 AM Wei Wang wrote: > > The lbr stack is architecturally specific, for example, SKX has 32 lbr > stack entries while HSW has 16 entries, so a HSW guest running on a SKX > machine may not get accurate perf results. Currently, we forbid the > guest lbr enabling when the guest and host see different lbr stack > entries. How do you handle live migration?