From patchwork Fri Sep 27 08:27:02 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wanpeng Li X-Patchwork-Id: 11164061 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 4BFF4924 for ; Fri, 27 Sep 2019 08:27:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 29CB12146E for ; Fri, 27 Sep 2019 08:27:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="l52EV2R5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726404AbfI0I1J (ORCPT ); Fri, 27 Sep 2019 04:27:09 -0400 Received: from mail-pl1-f195.google.com ([209.85.214.195]:33283 "EHLO mail-pl1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725842AbfI0I1J (ORCPT ); Fri, 27 Sep 2019 04:27:09 -0400 Received: by mail-pl1-f195.google.com with SMTP id d22so796726pls.0; Fri, 27 Sep 2019 01:27:08 -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; bh=6FZld6NyLvsWL2o4u7zTXB1hPtoeXTwRo8zEqYJfiKE=; b=l52EV2R5p6/wbHuZ7Du1+8xPCkXqUWWl864aST5vKDXKUTBIqq3H8Ft+uF3hmPZSlP nswHPvtegQrcrpzU0b+0j0PTNrQtFPyXxSQYRZ2hqnKU81L4TkaiXkTH15wy17ggAKhG A9Fkf4n9pAijobJf5+L6tupEp0mALV9v2yP2A+/uX3fJqvtZogTOa8pudagklRN8GSOH dcmgS+bdUiaFitQDifUxzjJP5sgKvQPejcCLC+21NNg9bsqr5J6u0F/wqHn7/WitwGnC mzmwDK83aQUp8neoaimuZoaMmPIjQ86l5+6i7a29NkCT1fGXkFT/Igg61ldxv4FfFeed YXOg== 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; bh=6FZld6NyLvsWL2o4u7zTXB1hPtoeXTwRo8zEqYJfiKE=; b=dDWiXhxs4zKIzSHAAM5r10l5H6XW+yy6nPMTuub4FPFCP4Z2PBxHmpTs//40HC0e0W sJL8jeZ2H8NqgBggT6njJTRsUfumBxoe6rL3GGmQ5MFDtnA7qRdGvpS1iyUZjvm3ZVGu DB4lptAgK03RDrR/AJD3kZetOTO5PpYg73ZIIXWqZ/QZbI/PsNOnwbBthuFZf+AnJdHk C6pEocIZ+6bPgY1fH6ir6X2O3WUr3wHJGnix/+JCrPWBBNq2PI06j0+7LDo7mYWNws6s 4oX3RUtG6qAsRk53hnHdwdMGd16D9QTzdYC7nT8DRQnj33llhF9xYBk7NelUFSDCn36W iUbg== X-Gm-Message-State: APjAAAVukFWyOUwrU0B+dfGyFgwAavi9Y59xLaKZijEJAbpIBaKpwxIe aHivzULd2OqKGnkdVSvzzC6kBJbd X-Google-Smtp-Source: APXvYqwzQglXoBTLIXgWxvQEeHnO8e7mA5or1UPjqdtSwLWyYE0B3CH2DugF5ttzoumQoESutBZ4Fw== X-Received: by 2002:a17:902:d201:: with SMTP id t1mr3117240ply.337.1569572828338; Fri, 27 Sep 2019 01:27:08 -0700 (PDT) Received: from localhost.localdomain ([203.205.141.123]) by smtp.googlemail.com with ESMTPSA id d24sm2168594pfn.86.2019.09.27.01.27.05 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Fri, 27 Sep 2019 01:27:07 -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?b?UmFkaW0gS3LEjW3DocWZ?= , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Marcelo Tosatti Subject: [PATCH] KVM: Don't shrink/grow vCPU halt_poll_ns if host side polling is disabled Date: Fri, 27 Sep 2019 16:27:02 +0800 Message-Id: <1569572822-28942-1-git-send-email-wanpengli@tencent.com> X-Mailer: git-send-email 2.7.4 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Wanpeng Li Don't waste cycles to shrink/grow vCPU halt_poll_ns if host side polling is disabled. Cc: Marcelo Tosatti Signed-off-by: Wanpeng Li --- virt/kvm/kvm_main.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index e6de315..b368be4 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2359,20 +2359,22 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu) kvm_arch_vcpu_unblocking(vcpu); block_ns = ktime_to_ns(cur) - ktime_to_ns(start); - if (!vcpu_valid_wakeup(vcpu)) - shrink_halt_poll_ns(vcpu); - else if (halt_poll_ns) { - if (block_ns <= vcpu->halt_poll_ns) - ; - /* we had a long block, shrink polling */ - else if (vcpu->halt_poll_ns && block_ns > halt_poll_ns) + if (!kvm_arch_no_poll(vcpu)) { + if (!vcpu_valid_wakeup(vcpu)) shrink_halt_poll_ns(vcpu); - /* we had a short halt and our poll time is too small */ - else if (vcpu->halt_poll_ns < halt_poll_ns && - block_ns < halt_poll_ns) - grow_halt_poll_ns(vcpu); - } else - vcpu->halt_poll_ns = 0; + else if (halt_poll_ns) { + if (block_ns <= vcpu->halt_poll_ns) + ; + /* we had a long block, shrink polling */ + else if (vcpu->halt_poll_ns && block_ns > halt_poll_ns) + shrink_halt_poll_ns(vcpu); + /* we had a short halt and our poll time is too small */ + else if (vcpu->halt_poll_ns < halt_poll_ns && + block_ns < halt_poll_ns) + grow_halt_poll_ns(vcpu); + } else + vcpu->halt_poll_ns = 0; + } trace_kvm_vcpu_wakeup(block_ns, waited, vcpu_valid_wakeup(vcpu)); kvm_arch_vcpu_block_finish(vcpu);