From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 19E58C46470 for ; Mon, 27 May 2019 10:34:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E61C9208CA for ; Mon, 27 May 2019 10:34:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="PyYO+5b1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726960AbfE0KeZ (ORCPT ); Mon, 27 May 2019 06:34:25 -0400 Received: from mail-pg1-f194.google.com ([209.85.215.194]:33421 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726946AbfE0KeY (ORCPT ); Mon, 27 May 2019 06:34:24 -0400 Received: by mail-pg1-f194.google.com with SMTP id h17so8910348pgv.0; Mon, 27 May 2019 03:34:24 -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:in-reply-to:references :mime-version:content-transfer-encoding; bh=Vpg2cDctWQejTN0F0qGalNdJQTFib3kHrQ/n0YmUAdw=; b=PyYO+5b16GmfOefyscRtRj3Z2WjyjUIpS+UlV0KmTktn6t90oEM4gQdAcdXGGBhvwX kH7+OFk1XLfQ2izT57PzI7xA64olkk58wHc49BoTNDVKWrk/LX5IJM8lUESeLJW9yfuF 3+/kaqqHvb4ZQC3UBjczm/vz5Ox1Boho4/46wFWPlTSgZuhbDJl2JZkG7/2BCtWoH8K3 mTPRA9HQoSaUckfDymaTuGGNBHasI7Fg65z5YsdhsV7emO0hhPjDDEP7h62Gd3ulQR2+ 9hn6TsOdwTlIUHlG77VK2yJvvgsVjWitydeVqNzpWgSsBxtHqR3h8l+A7v53o4o+0kap h8iw== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=Vpg2cDctWQejTN0F0qGalNdJQTFib3kHrQ/n0YmUAdw=; b=HlP77IDgA4c3ANnalZYl726tLWbdqqGTkcQLnwEYiuflJCiIuq5J0abesPBLINekZ5 /Phuj9QXl3SuYFVAGjmtLB6Py4nrJtlvlipiQrp2sDiKagViZNDpPZxIa5xmLASkh2ZO hns9j1iZuYCrbPWNnwWcI/D+Ibi9mv6q8A8PrtA3UpDsg3DCbq3zPbPZ+oGNOcZ5Vusa lSswl3gf+lXqinSGnN1CVc2tCZUSqv2qh+fkzbPI+g7UcBYE0wo5Tjv7tc0DqqHn/JZf 0uen8KE6x5tFcI3dDCefUmSZ5Ij8hy5+XH6Ms3gLvDOMgfngI0I9LY0g3VrjAbjDdKS1 cyLw== X-Gm-Message-State: APjAAAXSIILCB2o9k5L3hq7iM5AqL5gf6+U/EafFhB5l3sqSrmbn6cOe CcP2t8W6kCyGu81iWLbzGGAfU00l X-Google-Smtp-Source: APXvYqzt5TabbzEZfV9CZ9lZOdRVBBWybF9uBxkoZ3l8vJUzsPlArc0kJGvmPyJ2PznDqBjKthgyjw== X-Received: by 2002:a62:1846:: with SMTP id 67mr116709452pfy.33.1558953264163; Mon, 27 May 2019 03:34:24 -0700 (PDT) Received: from localhost.localdomain ([203.205.141.123]) by smtp.googlemail.com with ESMTPSA id y16sm19216452pfo.133.2019.05.27.03.34.22 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 27 May 2019 03:34:23 -0700 (PDT) From: Wanpeng Li X-Google-Original-From: Wanpeng Li To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= Subject: [PATCH 2/3] KVM: X86: Implement PV sched yield hypercall Date: Mon, 27 May 2019 18:34:14 +0800 Message-Id: <1558953255-9432-3-git-send-email-wanpengli@tencent.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1558953255-9432-1-git-send-email-wanpengli@tencent.com> References: <1558953255-9432-1-git-send-email-wanpengli@tencent.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Wanpeng Li The target vCPUs are in runnable state after vcpu_kick and suitable as a yield target. This patch implements the sched yield hypercall. 17% performace increase of ebizzy benchmark can be observed in an over-subscribe environment. (w/ kvm-pv-tlb disabled, testing TLB flush call-function IPI-many since call-function is not easy to be trigged by userspace workload). Cc: Paolo Bonzini Cc: Radim Krčmář Signed-off-by: Wanpeng Li --- arch/x86/kvm/x86.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index e7e57de..45403a6 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7172,6 +7172,19 @@ void kvm_vcpu_deactivate_apicv(struct kvm_vcpu *vcpu) kvm_x86_ops->refresh_apicv_exec_ctrl(vcpu); } +void kvm_sched_yield(struct kvm *kvm, u64 dest_id) +{ + struct kvm_vcpu *target; + struct kvm_apic_map *map; + + rcu_read_lock(); + map = rcu_dereference(kvm->arch.apic_map); + target = map->phys_map[dest_id]->vcpu; + rcu_read_unlock(); + + kvm_vcpu_yield_to(target); +} + int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) { unsigned long nr, a0, a1, a2, a3, ret; @@ -7218,6 +7231,10 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) case KVM_HC_SEND_IPI: ret = kvm_pv_send_ipi(vcpu->kvm, a0, a1, a2, a3, op_64_bit); break; + case KVM_HC_SCHED_YIELD: + kvm_sched_yield(vcpu->kvm, a0); + ret = 0; + break; default: ret = -KVM_ENOSYS; break; -- 2.7.4