From nobody Fri Dec 19 16:59:26 2025 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 04B06C4332F for ; Thu, 3 Nov 2022 02:51:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231294AbiKCCvG (ORCPT ); Wed, 2 Nov 2022 22:51:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42658 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231285AbiKCCux (ORCPT ); Wed, 2 Nov 2022 22:50:53 -0400 Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6EE0113EBD; Wed, 2 Nov 2022 19:50:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1667443850; x=1698979850; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=taX06KsU8mQXBQxKFDkHqGSkrqNdhC3yQd3XBk1YjEY=; b=CeKtBCj0x/ogv/QsliI8isa0w0OrNf97R7JgVQSWru0J+VNhkXfuMnUd vuxWpfheD3RRYh33X5bt30twBCRssonjos2Ob1LzrYBCbG9TRfW3RsgQR rDuIRawUC7ZklcRB77qV7B1eko7Q8KZuUVwl2X8fFax27GJAvjNIrhplP G/TWEhW8vCG+ACMuaYb2BTdc8SgLMVduM/Pgh/Q5rUSPwOFGHgBM4KKOt F93FCTc+RvbCwAvyKph0O3INoLWGJh+Jxp2D02XqOB/WeIa5LJcL4sNZE M7l+Z1tZ0ELWxD4ADIypDT+5jlfo/WGoc7dZNNN7MiHR78aJJL3oCHGgk Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10519"; a="308289832" X-IronPort-AV: E=Sophos;i="5.95,235,1661842800"; d="scan'208";a="308289832" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Nov 2022 19:50:50 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10519"; a="698047890" X-IronPort-AV: E=Sophos;i="5.95,235,1661842800"; d="scan'208";a="698047890" Received: from jiaxichen-precision-3650-tower.sh.intel.com ([10.239.159.75]) by fmsmga008.fm.intel.com with ESMTP; 02 Nov 2022 19:50:45 -0700 From: Jiaxi Chen To: kvm@vger.kernel.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, seanjc@google.com, pbonzini@redhat.com, ndesaulniers@google.com, alexandre.belloni@bootlin.com, peterz@infradead.org, jpoimboe@kernel.org, chang.seok.bae@intel.com, pawan.kumar.gupta@linux.intel.com, babu.moger@amd.com, jmattson@google.com, sandipan.das@amd.com, tony.luck@intel.com, sathyanarayanan.kuppuswamy@linux.intel.com, fenghua.yu@intel.com, keescook@chromium.org, nathan@kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 3/8] x86: KVM: Advertise CMPccXADD CPUID to user space Date: Thu, 3 Nov 2022 10:50:25 +0800 Message-Id: <20221103025030.78371-4-jiaxi.chen@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221103025030.78371-1-jiaxi.chen@linux.intel.com> References: <20221103025030.78371-1-jiaxi.chen@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" CMPccXADD is a new set of instructions in the latest Intel platform Sierra Forest. This new instruction set includes a semaphore operation that can compare and add the operands if condition is met, which can improve database performance. The bit definition: CPUID.(EAX=3D7,ECX=3D1):EAX[bit 7] This CPUID is exposed to userspace. Besides, there is no other VMX control for this instruction. Signed-off-by: Jiaxi Chen --- arch/x86/kvm/cpuid.c | 2 +- arch/x86/kvm/reverse_cpuid.h | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 89f5e7f0402b..b388ef52f8c8 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -657,7 +657,7 @@ void kvm_set_cpu_caps(void) kvm_cpu_cap_set(X86_FEATURE_SPEC_CTRL_SSBD); =20 kvm_cpu_cap_init_scattered(CPUID_7_1_EAX, - F(AVX_VNNI) | F(AVX512_BF16) + F(AVX_VNNI) | F(AVX512_BF16) | F(CMPCCXADD) ); =20 kvm_cpu_cap_mask(CPUID_D_1_EAX, diff --git a/arch/x86/kvm/reverse_cpuid.h b/arch/x86/kvm/reverse_cpuid.h index 674de5b24f8d..24f570ddb225 100644 --- a/arch/x86/kvm/reverse_cpuid.h +++ b/arch/x86/kvm/reverse_cpuid.h @@ -28,6 +28,7 @@ enum kvm_only_cpuid_leafs { /* Intel-defined sub-features, CPUID level 0x00000007:1 (EAX) */ #define X86_FEATURE_AVX_VNNI KVM_X86_FEATURE(CPUID_7_1_EAX, 4) #define X86_FEATURE_AVX512_BF16 KVM_X86_FEATURE(CPUID_7_1_EAX, 5) +#define X86_FEATURE_CMPCCXADD KVM_X86_FEATURE(CPUID_7_1_EAX, 7) =20 struct cpuid_reg { u32 function; --=20 2.27.0