From patchwork Sat Nov 9 07:05:35 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wanpeng Li X-Patchwork-Id: 11235813 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 633D71864 for ; Sat, 9 Nov 2019 07:06:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3CEDE21848 for ; Sat, 9 Nov 2019 07:06:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="nnha3lfJ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726383AbfKIHFp (ORCPT ); Sat, 9 Nov 2019 02:05:45 -0500 Received: from mail-pl1-f196.google.com ([209.85.214.196]:44821 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725861AbfKIHFp (ORCPT ); Sat, 9 Nov 2019 02:05:45 -0500 Received: by mail-pl1-f196.google.com with SMTP id az9so4462778plb.11; Fri, 08 Nov 2019 23:05:44 -0800 (PST) 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; bh=ZKFRaOW+bpKPizxwZqQQG7355BbFkJUXxhEyGAxMrv0=; b=nnha3lfJRQmONkwwgg50/QP/4dlQvjSaO5o5IPqzM9GS54CqrHf4BLZ4dLPQfM3Zen OF5a7jJpXT27bbSJDVzSnE++OQXlx9aNhCMbPPAnX6Utp4RK9hLGVSjxq0qV5SVpjh56 PTH3AQpujuhK0IyRwGCv6E5fV78vHIjZC0C7NCkz58aUQVJcuNwd7FThsXqdSwpVFU8f zWI4iEL3S3pmXvWc/ew0fu1YaHJ4QBiDzonEtPzKMfV1dO04bflyRjn9JqfSVKPYwF7+ 9Rz06tTW9w2ffLF7y9TPFi02IoLNqvIlLW5Lz7IB20ScIVyfjMFammz+TseXzEIthUOW ACDA== 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; bh=ZKFRaOW+bpKPizxwZqQQG7355BbFkJUXxhEyGAxMrv0=; b=tsYwt6jbJeGOgF1rqIZ8uQwtB3opZ2x9aoUsbLJbVvUJZYAs/znHYzllt7xawp779u XD53a342zkId8ohXhsQ70sigURcyJhX3zfHj8zeDf3cnsBghHs0o+3HxzfmRvEhNko2y dIvUCEpP+/34PlCHGL1vhtRqLIyPv9DDV/WTO/IM6Y1fKjoUWBLFqnY5enpsFZAduMaE /dJ62QnxIZXnmnBeOrxEVZUgNiqtDs0PQ2kL6cxW65ZvAF69QU3fP48NkVP514rEnzvJ OQCog4aKUjdORP8F3bjCf+cL5Kc7U/0jzwaXLf99JmrZVpQ09oVgEAJk+HuDwzmix+8p iyzg== X-Gm-Message-State: APjAAAXqFY00slSwtXh7AYfNav4/u3REUVwzqDf5qdInF1COkBRZCc8W CvKYfAUuObhH8mmDHsLGyoAPJiDp X-Google-Smtp-Source: APXvYqxvLpU0EGwB6Ipl7KdzI3cos3MwFxaj9xVmqoY7KF8XHkgILa0n1a3yb7lFMz5SW+7F5l1MLw== X-Received: by 2002:a17:902:b585:: with SMTP id a5mr14956646pls.191.1573283143879; Fri, 08 Nov 2019 23:05:43 -0800 (PST) Received: from localhost.localdomain ([203.205.141.123]) by smtp.googlemail.com with ESMTPSA id b200sm8337991pfb.86.2019.11.08.23.05.41 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Fri, 08 Nov 2019 23:05:43 -0800 (PST) From: Wanpeng Li X-Google-Original-From: Wanpeng Li To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Paolo Bonzini , =?utf-8?b?UmFkaW0gS3LEjW3DocWZ?= , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel Subject: [PATCH 2/2] KVM: LAPIC: micro-optimize fixed mode ipi delivery Date: Sat, 9 Nov 2019 15:05:35 +0800 Message-Id: <1573283135-5502-2-git-send-email-wanpengli@tencent.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1573283135-5502-1-git-send-email-wanpengli@tencent.com> References: <1573283135-5502-1-git-send-email-wanpengli@tencent.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Wanpeng Li After disabling mwait/halt/pause vmexits, RESCHEDULE_VECTOR and CALL_FUNCTION_SINGLE_VECTOR etc IPI is one of the main remaining cause of vmexits observed in product environment which can't be optimized by PV IPIs. This patch is the follow-up on commit 0e6d242eccdb (KVM: LAPIC: Micro optimize IPI latency), to optimize redundancy logic before fixed mode ipi is delivered in the fast path. - broadcast handling needs to go slow path, so the delivery mode repair can be delayed to before slow path. - self-IPI will not be intervened by hypervisor any more after APICv is introduced and the boxes support APICv are popular now. In addition, kvm_apic_map_get_dest_lapic() can handle the self-IPI, so there is no need a shortcut for the non-APICv case. Signed-off-by: Wanpeng Li --- arch/x86/kvm/irq_comm.c | 6 +++--- arch/x86/kvm/lapic.c | 5 ----- 2 files changed, 3 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c index 8ecd48d..aa88156 100644 --- a/arch/x86/kvm/irq_comm.c +++ b/arch/x86/kvm/irq_comm.c @@ -52,15 +52,15 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src, unsigned long dest_vcpu_bitmap[BITS_TO_LONGS(KVM_MAX_VCPUS)]; unsigned int dest_vcpus = 0; + if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map)) + return r; + if (irq->dest_mode == 0 && irq->dest_id == 0xff && kvm_lowest_prio_delivery(irq)) { printk(KERN_INFO "kvm: apic: phys broadcast and lowest prio\n"); irq->delivery_mode = APIC_DM_FIXED; } - if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map)) - return r; - memset(dest_vcpu_bitmap, 0, sizeof(dest_vcpu_bitmap)); kvm_for_each_vcpu(i, vcpu, kvm) { diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index b29d00b..ea936fa 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -951,11 +951,6 @@ bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src, *r = -1; - if (irq->shorthand == APIC_DEST_SELF) { - *r = kvm_apic_set_irq(src->vcpu, irq, dest_map); - return true; - } - rcu_read_lock(); map = rcu_dereference(kvm->arch.apic_map);