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=-9.8 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=ham 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 711A1C76191 for ; Thu, 18 Jul 2019 11:39:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 38D5621871 for ; Thu, 18 Jul 2019 11:39:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="CuDFDNHQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390073AbfGRLjO (ORCPT ); Thu, 18 Jul 2019 07:39:14 -0400 Received: from mail-pl1-f194.google.com ([209.85.214.194]:44210 "EHLO mail-pl1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726495AbfGRLjO (ORCPT ); Thu, 18 Jul 2019 07:39:14 -0400 Received: by mail-pl1-f194.google.com with SMTP id t14so13722078plr.11; Thu, 18 Jul 2019 04:39:13 -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=MmxGcGhhhPgISj08dbFbh46iPwYGrMKIu9SeI7KQRpY=; b=CuDFDNHQVLkTwYCuN4InUnJUAMEXhqoQxlPt9ex9Hti+TJuifdje7dzehm+92qgO0r uqjEiKOxSvMQ4Z0jo8CpzMX/LPMbilIPW3pZhFy5vlKb2iDafMG2eCB+vLDg4dxGg8Se Ldhj7VrwvGLzPZ7j73GH113S9a5QqDXpPwy5cjxw9SmAvq6pQU0Sf2OkcET//xai6u3d blfU7eGRjoz2YzMqnx82dQuIrSRmOAUOca0nRMNo2t2caDW6HEIc8hyKxrhVFpWLw+N5 58p8WjVe1VmWm7QLa7fH4pcvDt0I+PynXd7UklGS3MpPqsmHcbGDdH/VORpQT6EisbDe hwFQ== 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=MmxGcGhhhPgISj08dbFbh46iPwYGrMKIu9SeI7KQRpY=; b=L23ZrRWQs0x6GCVzfEDvDrpDWUleQ8YPjNZSGs+aj5z6eaRh83aPX5nxk4Ibp02RSp OM+kD5TPKSIL4+Y+uEKy356RnuBE8cCS7VQSEgRaB8xSflXPYdF2ShWFV9hUK03hxgvM eXbW8AtI4UbixIHiESq1mp9aclbCoSfFsfMNhvr7ZewTLrMAUW792OO83nbAJlJ6IumA YngV5RP9MuTWV3+SKm1eTI6mhYaVMiRTrc9a+NxpxBMOCr1Am4nt+vgdMpWhTwq0g628 m4rFLjHSwaOrz89h6usP5v29OgJffRFiZerz9vQydZUIOLMMgcTX1HcqZ4O2Hgmd5B1P FK7w== X-Gm-Message-State: APjAAAXOlTg9XTemiRfexG8aQtHPeibEiJmc0WY6OS6GQqB1DtHlav3y AKf4woozyIOOFRNO5RStqdugRg7D5d4= X-Google-Smtp-Source: APXvYqxLC4gzsgo2wx1PJJ+ObDrzz9h8I6f5ofIvI45cg0CcrS8JSHSajBOGak9Wcm+1AaSfVQ768A== X-Received: by 2002:a17:902:7087:: with SMTP id z7mr49036394plk.184.1563449953088; Thu, 18 Jul 2019 04:39:13 -0700 (PDT) Received: from localhost.localdomain ([203.205.141.123]) by smtp.googlemail.com with ESMTPSA id f15sm11908581pgu.2.2019.07.18.04.39.10 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 18 Jul 2019 04:39:12 -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?= , Christian Borntraeger , Paul Mackerras , Marc Zyngier Subject: [PATCH v2 1/2] KVM: Boosting vCPUs that are delivering interrupts Date: Thu, 18 Jul 2019 19:39:06 +0800 Message-Id: <1563449947-7749-1-git-send-email-wanpengli@tencent.com> X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Wanpeng Li Inspired by commit 9cac38dd5d (KVM/s390: Set preempted flag during vcpu wakeup and interrupt delivery), except the lock holder, we want to also boost vCPUs that are delivering interrupts. Actually most smp_call_function_many calls are synchronous ipi calls, the ipi target vCPUs are also good yield candidates. This patch introduces vcpu->ready to boost vCPUs during wakeup and interrupt delivery time. Testing on 80 HT 2 socket Xeon Skylake server, with 80 vCPUs VM 80GB RAM: ebizzy -M vanilla boosting improved 1VM 21443 23520 9% 2VM 2800 8000 180% 3VM 1800 3100 72% Testing on my Haswell desktop 8 HT, with 8 vCPUs VM 8GB RAM, two VMs, one running ebizzy -M, the other running 'stress --cpu 2': w/ boosting + w/o pv sched yield(vanilla) vanilla boosting improved 1570 4000 155% w/ boosting + w/ pv sched yield(vanilla) vanilla boosting improved 1844 5157 179% w/o boosting, perf top in VM: 72.33% [kernel] [k] smp_call_function_many 4.22% [kernel] [k] call_function_i 3.71% [kernel] [k] async_page_fault w/ boosting, perf top in VM: 38.43% [kernel] [k] smp_call_function_many 6.31% [kernel] [k] async_page_fault 6.13% libc-2.23.so [.] __memcpy_avx_unaligned 4.88% [kernel] [k] call_function_interrupt Cc: Paolo Bonzini Cc: Radim Krčmář Cc: Christian Borntraeger Cc: Paul Mackerras Cc: Marc Zyngier Signed-off-by: Wanpeng Li --- arch/s390/kvm/interrupt.c | 2 +- include/linux/kvm_host.h | 1 + virt/kvm/kvm_main.c | 12 +++++++++--- 3 files changed, 11 insertions(+), 4 deletions(-) diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index 9dde4d7..26f8bf4 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -1240,7 +1240,7 @@ void kvm_s390_vcpu_wakeup(struct kvm_vcpu *vcpu) * The vcpu gave up the cpu voluntarily, mark it as a good * yield-candidate. */ - vcpu->preempted = true; + vcpu->ready = true; swake_up_one(&vcpu->wq); vcpu->stat.halt_wakeup++; } diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index c5da875..5c5b586 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -318,6 +318,7 @@ struct kvm_vcpu { } spin_loop; #endif bool preempted; + bool ready; struct kvm_vcpu_arch arch; struct dentry *debugfs_dentry; }; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index b4ab59d..8412900 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2404,8 +2404,10 @@ void kvm_vcpu_kick(struct kvm_vcpu *vcpu) int me; int cpu = vcpu->cpu; - if (kvm_vcpu_wake_up(vcpu)) + if (kvm_vcpu_wake_up(vcpu)) { + vcpu->ready = true; return; + } me = get_cpu(); if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu)) @@ -2500,7 +2502,7 @@ void kvm_vcpu_on_spin(struct kvm_vcpu *me, bool yield_to_kernel_mode) continue; } else if (pass && i > last_boosted_vcpu) break; - if (!READ_ONCE(vcpu->preempted)) + if (!READ_ONCE(vcpu->ready)) continue; if (vcpu == me) continue; @@ -4205,6 +4207,8 @@ static void kvm_sched_in(struct preempt_notifier *pn, int cpu) if (vcpu->preempted) vcpu->preempted = false; + if (vcpu->ready) + vcpu->ready = false; kvm_arch_sched_in(vcpu, cpu); @@ -4216,8 +4220,10 @@ static void kvm_sched_out(struct preempt_notifier *pn, { struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn); - if (current->state == TASK_RUNNING) + if (current->state == TASK_RUNNING) { vcpu->preempted = true; + vcpu->ready = true; + } kvm_arch_vcpu_put(vcpu); } -- 2.7.4