From patchwork Tue Apr 17 08:05:37 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Wanpeng Li X-Patchwork-Id: 899127 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="P3daTIw8"; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 40QHsW5r86z9s0n for ; Tue, 17 Apr 2018 18:07:11 +1000 (AEST) Received: from localhost ([::1]:50271 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f8Ldt-0001Er-QP for incoming@patchwork.ozlabs.org; Tue, 17 Apr 2018 04:07:09 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53497) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f8LdK-0001BY-Hu for qemu-devel@nongnu.org; Tue, 17 Apr 2018 04:06:35 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1f8LdG-00066M-9w for qemu-devel@nongnu.org; Tue, 17 Apr 2018 04:06:34 -0400 Received: from mail-pg0-x244.google.com ([2607:f8b0:400e:c05::244]:37198) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1f8LdG-00065F-1z for qemu-devel@nongnu.org; Tue, 17 Apr 2018 04:06:30 -0400 Received: by mail-pg0-x244.google.com with SMTP id r14so5048973pgq.4 for ; Tue, 17 Apr 2018 01:06:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=M4y1GRIfKTg9ClgdKlzJ6Lw01L5sEFVYGPUKs5vBHCE=; b=P3daTIw8bKygKJOCjzPHGFlZ9+qJHIhJyzivvqEhFYoDYFS3YZ3NvbQLFVKxzwzRpV 1f0LPFDG7eKNgxBOMvGkjb0SjEgw+8qe9OuMY/TWYJ8pvynAQ+etlxZ6rXVUu/8tNJnE vHpMy7csi1Mai3DEdvNykwvu1R8wDpfGOHbA/k9nIOS9aZfOyeoyZemw6/NYrnZzD7TJ EJFyOqErYdA7iGEB/giMazFSepovm4T3gz0L3GCOFnDS8/8Syuq6UheHJ8arMwlSu6hg duvGFJnRhZOHbhA8nTmfARfvY3pcs/n9eQccjPiTt+HNrxnLWd7KrZ+IfRWkl2Nr8iSz BVzA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=M4y1GRIfKTg9ClgdKlzJ6Lw01L5sEFVYGPUKs5vBHCE=; b=ZU9jPAMkrL2tByn2GcjinWLAPGwvW5/QGWFiM7bPvTFsic9bR5pQclLGawXS5oolc/ QxgyBjIaQgF01Y3nLJJlSrNbl418tk5xYwVutzuC4gCH9QcCPVvNgHCcWVbgY2ZTjOiM tWVkFwrbhcuQdf7BZ3jOQkCfFOyKy4zTJUedjtpm/fX2NfcqcUHoOsPKWO2aSaF+btmi cjcsXbzQhA5APQ406eLQlXP9YhH5DrooC4F27KBm/HzaX8ZqROCh6WYhRUAQonZsSMtw zP1ZG+H5xY+DPpOicoJYeLV2T85dlcE1YZZvBf232EbWp1g9vl6q1wZrlmSPzHPIWyyD AMeQ== X-Gm-Message-State: ALQs6tB31uAfm1lyBGUjTYT5ZxibJpMfBvpoMOs7dmCmn/rS9+6uv02W Hrn0N5G1VpzYL/Y67zMlnQbqjw== X-Google-Smtp-Source: AIpwx4+xCvMEgjkPrl45vTF6ANroAHNfmF/hBGVduG6WI5WYu/wgfpxuzyaiXCN6ZOjw7TczJ9pPEg== X-Received: by 10.101.64.201 with SMTP id u9mr1009317pgp.142.1523952388877; Tue, 17 Apr 2018 01:06:28 -0700 (PDT) Received: from localhost.localdomain ([203.205.141.123]) by smtp.googlemail.com with ESMTPSA id n83sm11483853pfi.183.2018.04.17.01.06.26 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 17 Apr 2018 01:06:28 -0700 (PDT) From: Wanpeng Li X-Google-Original-From: Wanpeng Li To: qemu-devel@nongnu.org, kvm@vger.kernel.org Date: Tue, 17 Apr 2018 01:05:37 -0700 Message-Id: <1523952337-27449-1-git-send-email-wanpengli@tencent.com> X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:400e:c05::244 Subject: [Qemu-devel] [PATCH v2] i386/kvm: add support for KVM_CAP_X86_DISABLE_EXITS X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paolo Bonzini , Eduardo Habkost , =?utf-8?b?UmFkaW0gS3LEjW3DocWZ?= Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Wanpeng Li This patch adds support for KVM_CAP_X86_DISABLE_EXITS. Provides userspace with per-VM capability(KVM_CAP_X86_DISABLE_EXITS) to not intercept MWAIT/HLT/PAUSE in order that to improve latency in some workloads. Cc: Paolo Bonzini Cc: Radim Krčmář Cc: Eduardo Habkost Signed-off-by: Wanpeng Li --- v1 -> v2: * disable kvm-hint-dedicated if kvm-pv-unhalt is specified linux-headers/linux/kvm.h | 6 +++++- target/i386/cpu.h | 2 ++ target/i386/kvm.c | 15 +++++++++++++++ 3 files changed, 22 insertions(+), 1 deletion(-) diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h index a167be8..857df15 100644 --- a/linux-headers/linux/kvm.h +++ b/linux-headers/linux/kvm.h @@ -925,7 +925,7 @@ struct kvm_ppc_resize_hpt { #define KVM_CAP_S390_GS 140 #define KVM_CAP_S390_AIS 141 #define KVM_CAP_SPAPR_TCE_VFIO 142 -#define KVM_CAP_X86_GUEST_MWAIT 143 +#define KVM_CAP_X86_DISABLE_EXITS 143 #define KVM_CAP_ARM_USER_IRQ 144 #define KVM_CAP_S390_CMMA_MIGRATION 145 #define KVM_CAP_PPC_FWNMI 146 @@ -1508,6 +1508,10 @@ struct kvm_assigned_msix_entry { #define KVM_X2APIC_API_USE_32BIT_IDS (1ULL << 0) #define KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK (1ULL << 1) +#define KVM_X86_DISABLE_EXITS_MWAIT (1 << 0) +#define KVM_X86_DISABLE_EXITS_HLT (1 << 1) +#define KVM_X86_DISABLE_EXITS_PAUSE (1 << 2) + /* Available with KVM_CAP_ARM_USER_IRQ */ /* Bits for run->s.regs.device_irq_level */ diff --git a/target/i386/cpu.h b/target/i386/cpu.h index 1b219fa..965de1b 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -685,6 +685,8 @@ typedef uint32_t FeatureWordArray[FEATURE_WORDS]; #define CPUID_7_0_EDX_AVX512_4FMAPS (1U << 3) /* AVX512 Multiply Accumulation Single Precision */ #define CPUID_7_0_EDX_SPEC_CTRL (1U << 26) /* Speculation Control */ +#define KVM_PV_UNHALT (1U << 7) + #define KVM_HINTS_DEDICATED (1U << 0) #define CPUID_8000_0008_EBX_IBPB (1U << 12) /* Indirect Branch Prediction Barrier */ diff --git a/target/i386/kvm.c b/target/i386/kvm.c index 6c49954..9357caa 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -1029,6 +1029,21 @@ int kvm_arch_init_vcpu(CPUState *cs) } } + if (env->features[FEAT_KVM_HINTS] & KVM_HINTS_DEDICATED) { + int disable_exits = kvm_check_extension(cs->kvm_state, KVM_CAP_X86_DISABLE_EXITS); + + if (disable_exits) { + disable_exits &= (KVM_X86_DISABLE_EXITS_MWAIT | + KVM_X86_DISABLE_EXITS_HLT | + KVM_X86_DISABLE_EXITS_PAUSE); + if (env->user_features[KVM] & KVM_PV_UNHALT) + disable_exits &= ~KVM_X86_DISABLE_EXITS_HLT; + } + if (kvm_vm_enable_cap(cs->kvm_state, KVM_CAP_X86_DISABLE_EXITS, 0, disable_exits)) { + error_report("kvm: DISABLE EXITS not supported"); + } + } + qemu_add_vm_change_state_handler(cpu_update_state, env); c = cpuid_find_entry(&cpuid_data.cpuid, 1, 0);