From patchwork Tue Oct 4 22:56:43 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Graf X-Patchwork-Id: 12998764 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 4C22AC433F5 for ; Tue, 4 Oct 2022 23:02:03 +0000 (UTC) Received: from localhost ([::1]:42258 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ofqvJ-0005Z4-RM for qemu-devel@archiver.kernel.org; Tue, 04 Oct 2022 19:02:01 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42362) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ofqqR-00039B-6V for qemu-devel@nongnu.org; Tue, 04 Oct 2022 18:57:02 -0400 Received: from mail.csgraf.de ([85.25.223.15]:51102 helo=zulu616.server4you.de) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ofqqO-0000HM-Je for qemu-devel@nongnu.org; Tue, 04 Oct 2022 18:56:57 -0400 Received: from localhost.localdomain (dynamic-095-117-005-115.95.117.pool.telefonica.de [95.117.5.115]) by csgraf.de (Postfix) with ESMTPSA id 8AB776080FDE; Wed, 5 Oct 2022 00:56:47 +0200 (CEST) From: Alexander Graf To: qemu-devel@nongnu.org Cc: kvm@vger.kernel.org, Eduardo Habkost , Richard Henderson , Marcelo Tosatti , Paolo Bonzini , Vladislav Yaroshchuk , Roman Bolshakov Subject: [PATCH 3/3] KVM: x86: Implement MSR_CORE_THREAD_COUNT MSR Date: Wed, 5 Oct 2022 00:56:43 +0200 Message-Id: <20221004225643.65036-4-agraf@csgraf.de> X-Mailer: git-send-email 2.37.0 (Apple Git-136) In-Reply-To: <20221004225643.65036-1-agraf@csgraf.de> References: <20221004225643.65036-1-agraf@csgraf.de> MIME-Version: 1.0 Received-SPF: pass client-ip=85.25.223.15; envelope-from=agraf@csgraf.de; helo=zulu616.server4you.de X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 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" The MSR_CORE_THREAD_COUNT MSR describes CPU package topology, such as number of threads and cores for a given package. This is information that QEMU has readily available and can provide through the new user space MSR deflection interface. This patch propagates the existing hvf logic from patch 027ac0cb516 ("target/i386/hvf: add rdmsr 35H MSR_CORE_THREAD_COUNT") to KVM. Signed-off-by: Alexander Graf --- target/i386/kvm/kvm.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c index ea53092dd0..791e995389 100644 --- a/target/i386/kvm/kvm.c +++ b/target/i386/kvm/kvm.c @@ -2403,6 +2403,17 @@ static int kvm_get_supported_msrs(KVMState *s) return ret; } +static bool kvm_rdmsr_core_thread_count(X86CPU *cpu, uint32_t msr, + uint64_t *val) +{ + CPUState *cs = CPU(cpu); + + *val = cs->nr_threads * cs->nr_cores; /* thread count, bits 15..0 */ + *val |= ((uint32_t)cs->nr_cores << 16); /* core count, bits 31..16 */ + + return true; +} + static Notifier smram_machine_done; static KVMMemoryListener smram_listener; static AddressSpace smram_address_space; @@ -2591,6 +2602,8 @@ int kvm_arch_init(MachineState *ms, KVMState *s) } if (kvm_vm_check_extension(s, KVM_CAP_X86_USER_SPACE_MSR)) { + bool r; + ret = kvm_vm_enable_cap(s, KVM_CAP_X86_USER_SPACE_MSR, 0, KVM_MSR_EXIT_REASON_FILTER); if (ret) { @@ -2598,6 +2611,14 @@ int kvm_arch_init(MachineState *ms, KVMState *s) strerror(-ret)); exit(1); } + + r = kvm_filter_msr(s, MSR_CORE_THREAD_COUNT, + kvm_rdmsr_core_thread_count, NULL); + if (!r) { + error_report("Could not install MSR_CORE_THREAD_COUNT handler: %s", + strerror(-ret)); + exit(1); + } } return 0;