From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f73.google.com (mail-pj1-f73.google.com [209.85.216.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 23DDC3717B for ; Thu, 11 Apr 2024 21:50:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712872232; cv=none; b=gRQOE2crI+bNRrEIhPsSHUk/kpVErdSKc9aPaoSCDMl85zOxkEslh52Jg+I5YfR5Ny6M2DiFbfWv9er1c2JuwwMNHRVezlhE6ca2WU7U6fJdgYzBduHmhOrKmDaaVxQ92eAd/PcYBKj1QDLuQPaWBb6dd5z9fzIlfFUsIDA9z9Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712872232; c=relaxed/simple; bh=PQIRuDalA81RPfew+1oM3M1PbSo25ZD+Ob2cgUdhwRI=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=PMBR+m39AS0yvycu2+A2CvJXtAmpTf7xfbyWg9jszwzjIkuyH0K7GzDl/E7cEJ9CteBlT3RuDqyBgWc6m7vCiGE8fdBYA1Gr80wpazo0ELrzrl6tGfEX3YzzPdePOMpX0sajaBRYDzMHJ3eVVZH3n4/Pidr5gk3qtOBaSlfcfxQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=GKEzWTFn; arc=none smtp.client-ip=209.85.216.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="GKEzWTFn" Received: by mail-pj1-f73.google.com with SMTP id 98e67ed59e1d1-2a2d197ac0aso207050a91.2 for ; Thu, 11 Apr 2024 14:50:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1712872230; x=1713477030; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=iaCjUmmDdIOzJKGmZpSSyoXs6qkh/GpGaJ06mDLpr1M=; b=GKEzWTFnf5sVuP0IUxt9A8GWbiHHX2Mhwox/3lpnLdb2vU1bICHLAOfcG/J2ZFYjil s09kZ5UdRAIiktwxg/vbbtLbEAA0GH9FaK+yKfZGXP15hQUlr1gooptkXJpAy7PDawaq 45e3lpgP8bPE13sKW+G5oM1K2wLyppneMZO2cxpDJFX6VYuDZlnjKhDf6GqdSeSs5IOc XUKLlc5abihqtOUywwM88GIirK9qiqmC/ST3fINtcCIrCd3FOLxlU6R4MnYoTKX/a2L+ xD9w0LUQWLUL/v3zL9GudEMtKl3nRZYD6P8jUtLFieblMj8EeVhg69CsHxKxzwfYdme5 x6dA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1712872230; x=1713477030; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=iaCjUmmDdIOzJKGmZpSSyoXs6qkh/GpGaJ06mDLpr1M=; b=OFIGPoVvcRow+CZYuMXU2CPOUF4BiAwQTxXXjIWdeqxoTiogJBFMJR3qn2eBP/ZXhl gVKSawugVe6HNvegTUUl1jeHCiVmQXrnOrUO5cc6W3BaofsXMnLZDtpNY5Nxelciy3iB raDqVoy8r36QDNC/w/sM+agI8lQUB7Xyukz9vzA6JGrjVbr+YEy9rW0i4g6n1I9Xki0w whQFEYfJLtMrBYcFzujRvX1uVF5y64MxA9zUplSoHd6anN/fO9NEIhNdVgXZfj0jeu2N 4sRC00ORYxB8+EZN1nk9GmcTIOuDFywlb8/59sM6GcKDyc6GY3xbw5NTHE2SKrf0py39 2qyg== X-Forwarded-Encrypted: i=1; AJvYcCWiKWFbcKdOjX9GDgfPcmp4r8mjtVaVwSEPtCDQpKugsYROD55MHE3K4EPuIW+EiOrDHTkMMwWNNIoLutCNaepl60Do29B4sMEBr77EZZ+RSQ== X-Gm-Message-State: AOJu0YxORoOQTMzWb7j2DV+wA9bGfp6x95S+tW2a1zbCrBrlNauhYMDR UxF64WmXv5H+1gvbkmt3I0HL6XUuXUsvCRnpCclEBTKk/cO+rg0Np8EPY4UJBRHDBxjVwTPTYtc HHw== X-Google-Smtp-Source: AGHT+IHoU3vWBVtinqVLN1A8TwfMLrhsEG6lZ6A6/VWf1bt/DoqDl+FQZvyCl4pbADg3UfMsA+vwmkWh0kw= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a17:90b:128f:b0:2a4:8940:41c7 with SMTP id fw15-20020a17090b128f00b002a4894041c7mr2248pjb.4.1712872230439; Thu, 11 Apr 2024 14:50:30 -0700 (PDT) Date: Thu, 11 Apr 2024 14:50:28 -0700 In-Reply-To: <20240126085444.324918-28-xiong.y.zhang@linux.intel.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240126085444.324918-1-xiong.y.zhang@linux.intel.com> <20240126085444.324918-28-xiong.y.zhang@linux.intel.com> Message-ID: Subject: Re: [RFC PATCH 27/41] KVM: x86/pmu: Clear PERF_METRICS MSR for guest From: Sean Christopherson To: Xiong Zhang Cc: pbonzini@redhat.com, peterz@infradead.org, mizhang@google.com, kan.liang@intel.com, zhenyuw@linux.intel.com, dapeng1.mi@linux.intel.com, jmattson@google.com, kvm@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, zhiyuan.lv@intel.com, eranian@google.com, irogers@google.com, samantha.alt@intel.com, like.xu.linux@gmail.com, chao.gao@intel.com Content-Type: text/plain; charset="us-ascii" On Fri, Jan 26, 2024, Xiong Zhang wrote: > From: Dapeng Mi > > Since perf topdown metrics feature is not supported yet, clear > PERF_METRICS MSR for guest. Please rewrite with --verbose, I have no idea what MSR_PERF_METRICS, and thus no clue why it needs to be zeroed when loading guest context, e.g. it's not passed through, so why does it matter? > Signed-off-by: Dapeng Mi > --- > arch/x86/kvm/vmx/pmu_intel.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c > index 4b4da7f17895..ad0434646a29 100644 > --- a/arch/x86/kvm/vmx/pmu_intel.c > +++ b/arch/x86/kvm/vmx/pmu_intel.c > @@ -916,6 +916,10 @@ static void intel_restore_pmu_context(struct kvm_vcpu *vcpu) > */ > for (i = pmu->nr_arch_fixed_counters; i < kvm_pmu_cap.num_counters_fixed; i++) > wrmsrl(MSR_CORE_PERF_FIXED_CTR0 + i, 0); > + > + /* Clear PERF_METRICS MSR since guest topdown metrics is not supported yet. */ > + if (kvm_caps.host_perf_cap & PMU_CAP_PERF_METRICS) > + wrmsrl(MSR_PERF_METRICS, 0); > } > > struct kvm_pmu_ops intel_pmu_ops __initdata = { > -- > 2.34.1 >