From nobody Mon Feb 9 10:28:56 2026 Received: from mail-yw1-f201.google.com (mail-yw1-f201.google.com [209.85.128.201]) (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 1CCB31E2311 for ; Thu, 21 Nov 2024 18:53:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732215230; cv=none; b=fSUj9NytRHRN+XbLRJahrZtzHsoDGbD7DRhdDh8v4R4eApcxrHZRC1jZzJZwKLBUFqAt1BjkE1ct6NDxW1tDDFGi6xqW4lZk0vZOU0Q/DQ/bg669lSmBEPVERKSAz+Mg/FNtWe90YkzLAaX1n17Ewy0b74ges+lX9MacjzTalJ8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732215230; c=relaxed/simple; bh=eHXZPCixs0Kp9lb7wTpd1eAC5lTE/wHduYYezTPcltI=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=FHQ5tWkNw32KA8yOQASNOjAMmI067o6dXTpuTMy7tyKodAYlhgZ7hDCeaWRDoBQpWBASXgoK9uTS2rAOy7gpkN4G6TOcOMzoJVWIPAZir48FtqRtJn4bKY3X3xBbdUf1KuHoz/8FRjQ5InstAjjaZOn+RElcUVvDSy4ZvslraKc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--mizhang.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=2Q3vNv8L; arc=none smtp.client-ip=209.85.128.201 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--mizhang.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="2Q3vNv8L" Received: by mail-yw1-f201.google.com with SMTP id 00721157ae682-6eebd4e7cc5so14918397b3.0 for ; Thu, 21 Nov 2024 10:53:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1732215227; x=1732820027; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=S3ejUU/7aVBo5O4Q0RNsvCKZVgKY1XQah2zaS1IN8Y8=; b=2Q3vNv8LrR2WteR3PRdx5a0g0bxBUBMmsz/1ptNtGsXDSdQHBv8If8DdkSLHMCr8mK Ryy8n1eERwWnj6OGFjS7EuhJNu4Lu0eflomgCC62OJ4pNP9W9mmGSTrCG8qJ21UQ0m/Y XtT55v1s0frhm3EIGGYIDTD78wCmIWP4ukINQpSHy3okwpTGqBIaB0H1H2/fRL4EEj+Y XOE1UEIUFcaVlo7oZe+dF1sx+pXzgf3u5j/YTxG5LJ2r9upJTt6YmU/fXmMZAwWZmB7h OGvbPHgdyMQCFxnvi4BTPas6DrTmZ7rHKPG2Ag/wbrsscOjyBu1GDIaWbNPYyWFeml/p B7Hg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1732215227; x=1732820027; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=S3ejUU/7aVBo5O4Q0RNsvCKZVgKY1XQah2zaS1IN8Y8=; b=NhSmKKXpgRj87wZ5HBmFQTAFHzoU7o0/TGmgK3cm/1fe6ZCrmjg1jaL1MilaTlbZPl TsEpf85cUUfK212kuIwL4aDuPtdUlx0d7rhnAaNBE9kYjiY4Twm738VmM5+UOZM7215u pt95ZdyRX1Z078AC60ZGhaiP0bBS3LH+4e9n8JR+xpTW3EHvTW8Revf4E6DA1FdqegxA x/i66Yl2aqbYE1wRi0u+Fb2LGaqcBnW2CRFg4tHuutSEVAZbqUF5uQg9Exn4ssV8ToCU GXQ+TwNIneNgEzmTaumCJlFfNEz8RBTeqwx2dwqSRjyQMj81y+14VTW9t4+hvRR0lxFS lm9A== X-Forwarded-Encrypted: i=1; AJvYcCWjNXPM/EaAq4T0PMnppmopgDozp3TUwdhM2rDPnydVLOUNOTQVPQ2CF/15SeTHf8X+DV3kGt4ynHy7wKk=@vger.kernel.org X-Gm-Message-State: AOJu0Yy4z5yPei90+saWklaj1TrfNBmkM9VDwsdE+8MjEqts1b5DBKXW jAeWqy1uBfOmFst40jqpaX9jBqa1FfxKr8XkY6LGieT3jXBFx782IMNeb1sVpkeQGyiShDIoHWI vp6Ykvw== X-Google-Smtp-Source: AGHT+IFnZhLdaAm9Iv4V2heWNMD+AOPfEaQHbFcWJ8d4iuBWsqxwVlNaJU/yAnomaTfOoVWSEqQuOYrN36SC X-Received: from mizhang-super.c.googlers.com ([35.247.89.60]) (user=mizhang job=sendgmr) by 2002:a81:a742:0:b0:6ee:a2b0:a803 with SMTP id 00721157ae682-6eecd2b215emr527207b3.1.1732215227332; Thu, 21 Nov 2024 10:53:47 -0800 (PST) Reply-To: Mingwei Zhang Date: Thu, 21 Nov 2024 18:53:09 +0000 In-Reply-To: <20241121185315.3416855-1-mizhang@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241121185315.3416855-1-mizhang@google.com> X-Mailer: git-send-email 2.47.0.371.ga323438b13-goog Message-ID: <20241121185315.3416855-18-mizhang@google.com> Subject: [RFC PATCH 17/22] KVM: x86: Save guest [am]perf checkpoint on vcpu_put() From: Mingwei Zhang To: Sean Christopherson , Paolo Bonzini , Huang Rui , "Gautham R. Shenoy" , Mario Limonciello , "Rafael J. Wysocki" , Viresh Kumar , Srinivas Pandruvada , Len Brown Cc: "H. Peter Anvin" , Perry Yuan , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, Jim Mattson , Mingwei Zhang Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" For vCPUs with APERFMPERF that are in KVM_RUN and not halted, checkpoint the current hardware MSR values along with the host TSC when unloading the vCPU. While still in virtual C0 state, the vCPU will no longer run on this physical CPU, requiring different handling for each counter: - IA32_APERF should stop accumulating since no actual CPU cycles are being spent on behalf of the guest - IA32_MPERF should continue accumulating cycles since the guest is still in C0 state Later when the vCPU is reloaded, we'll use this checkpoint and the host TSC delta to properly account for any "background" cycles that should be reflected in the guest's IA32_MPERF value. Signed-off-by: Mingwei Zhang Co-developed-by: Jim Mattson Signed-off-by: Jim Mattson --- arch/x86/kvm/x86.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 793f5d2afeb2b..7c22bda3b1f7b 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5173,6 +5173,11 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) srcu_read_unlock(&vcpu->kvm->srcu, idx); } =20 + if (vcpu->wants_to_run && + guest_can_use(vcpu, X86_FEATURE_APERFMPERF) && + vcpu->arch.aperfmperf.loaded_while_running) + kvm_put_guest_aperfmperf(vcpu); + kvm_x86_call(vcpu_put)(vcpu); vcpu->arch.last_host_tsc =3D rdtsc(); } --=20 2.47.0.371.ga323438b13-goog