From patchwork Sat Sep 23 00:41:56 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoffer Dall X-Patchwork-Id: 9967305 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id ED6B3602CB for ; Sat, 23 Sep 2017 00:42:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E000B29590 for ; Sat, 23 Sep 2017 00:42:29 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D50F1299C6; Sat, 23 Sep 2017 00:42:29 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7673629590 for ; Sat, 23 Sep 2017 00:42:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752638AbdIWAm2 (ORCPT ); Fri, 22 Sep 2017 20:42:28 -0400 Received: from mail-wm0-f44.google.com ([74.125.82.44]:45655 "EHLO mail-wm0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752477AbdIWAmS (ORCPT ); Fri, 22 Sep 2017 20:42:18 -0400 Received: by mail-wm0-f44.google.com with SMTP id q124so7623195wmb.0 for ; Fri, 22 Sep 2017 17:42:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=7frvHj8Ks/CAnwGSe5toUzTWor2DyNyyLKU+Zu+b2Qc=; b=ehLTulgsHbttP15nzDzIaP1DyZl/3Wm0OS4HR2eo56SEdZp6R7C1nAEU7p8YqJN0fb s3BNSeaAKzzUarUXCrp4y7FBr3jmmLzrgxhyfmZH/9+i+9igst3SV3fzYcZdvWWAFBUm AifzhpnIrRPqFFSVufhB9SDXVD6cnKz1R0lEs= 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=7frvHj8Ks/CAnwGSe5toUzTWor2DyNyyLKU+Zu+b2Qc=; b=tpJIMd6ShncgO/p22KQKtcsZxlvh4SH9AotVJTFB6c+x/ewZvW991HZNb0eTjEB1y6 W4BByAOolZ+hBH528o9axrYzmpe5wCeSS5SEh67DBd0NJJKjA4F+bKrheucGozGNwYBX PdYuQtAhhchE72sUo9M0YaJTgHCTboDZCMQoZcXk1VXvAk3ea6X1TZFMPxQFju8WaXb3 dVe5/FS9xZTb9yVBFlZsH8oPPbTtKaUYl7mkf+nLivK5XfSyw1Zz4V3RMQeFbPkXJzcc ah0Ym7/m3dQgMw8fOAf0m0FBIjdSXqWpQRlYQKKzieXHGJIckZfj5sNBPbZ9pkTwZ8y5 wLHA== X-Gm-Message-State: AHPjjUhIic35gScY0xQx5yOF/gSqzK2zi9oeaMMc6VkzhI6CyGtcev+s iz1om72lK4OSBSxWSMFwx77zRrmUdQk= X-Google-Smtp-Source: AOwi7QAfjjJ+bD7uw9IhBgUXT3e48Fs82nhAwwEke3r4B4fb4QEOPb0ceKdtmcOGmU+gokh7yzffJw== X-Received: by 10.80.179.247 with SMTP id t52mr6342671edd.237.1506127337521; Fri, 22 Sep 2017 17:42:17 -0700 (PDT) Received: from localhost.localdomain (xd93dd96b.cust.hiper.dk. [217.61.217.107]) by smtp.gmail.com with ESMTPSA id c25sm646085edb.57.2017.09.22.17.42.16 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Fri, 22 Sep 2017 17:42:16 -0700 (PDT) From: Christoffer Dall To: kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org Cc: kvm@vger.kernel.org, Marc Zyngier , Will Deacon , Catalin Marinas , Christoffer Dall Subject: [PATCH v3 09/20] KVM: arm/arm64: Use separate timer for phys timer emulation Date: Sat, 23 Sep 2017 02:41:56 +0200 Message-Id: <20170923004207.22356-10-cdall@linaro.org> X-Mailer: git-send-email 2.9.0 In-Reply-To: <20170923004207.22356-1-cdall@linaro.org> References: <20170923004207.22356-1-cdall@linaro.org> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP We were using the same hrtimer for emulating the physical timer and for making sure a blocking VCPU thread would be eventually woken up. That worked fine in the previous arch timer design, but as we are about to actually use the soft timer expire function for the physical timer emulation, change the logic to use a dedicated hrtimer. This has the added benefit of not having to cancel any work in the sync path, which in turn allows us to run the flush and sync with IRQs disabled. Signed-off-by: Christoffer Dall --- include/kvm/arm_arch_timer.h | 3 +++ virt/kvm/arm/arch_timer.c | 18 ++++++++++++++---- 2 files changed, 17 insertions(+), 4 deletions(-) diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h index dcbb2e1..16887c0 100644 --- a/include/kvm/arm_arch_timer.h +++ b/include/kvm/arm_arch_timer.h @@ -47,6 +47,9 @@ struct arch_timer_cpu { /* Work queued with the above timer expires */ struct work_struct expired; + /* Physical timer emulation */ + struct hrtimer phys_timer; + /* Background timer active */ bool armed; diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c index c2e8326..7f87099 100644 --- a/virt/kvm/arm/arch_timer.c +++ b/virt/kvm/arm/arch_timer.c @@ -178,6 +178,12 @@ static enum hrtimer_restart kvm_bg_timer_expire(struct hrtimer *hrt) return HRTIMER_NORESTART; } +static enum hrtimer_restart kvm_phys_timer_expire(struct hrtimer *hrt) +{ + WARN(1, "Timer only used to ensure guest exit - unexpected event."); + return HRTIMER_NORESTART; +} + bool kvm_timer_should_fire(struct arch_timer_context *timer_ctx) { u64 cval, now; @@ -255,7 +261,7 @@ static void kvm_timer_update_state(struct kvm_vcpu *vcpu) } /* Schedule the background timer for the emulated timer. */ -static void kvm_timer_emulate(struct kvm_vcpu *vcpu, +static void phys_timer_emulate(struct kvm_vcpu *vcpu, struct arch_timer_context *timer_ctx) { struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; @@ -267,7 +273,7 @@ static void kvm_timer_emulate(struct kvm_vcpu *vcpu, return; /* The timer has not yet expired, schedule a background timer */ - soft_timer_start(&timer->bg_timer, kvm_timer_compute_delta(timer_ctx)); + soft_timer_start(&timer->phys_timer, kvm_timer_compute_delta(timer_ctx)); } /* @@ -424,7 +430,7 @@ void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu) kvm_timer_update_state(vcpu); /* Set the background timer for the physical timer emulation. */ - kvm_timer_emulate(vcpu, vcpu_ptimer(vcpu)); + phys_timer_emulate(vcpu, vcpu_ptimer(vcpu)); if (unlikely(!irqchip_in_kernel(vcpu->kvm))) kvm_timer_flush_hwstate_user(vcpu); @@ -447,7 +453,7 @@ void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu) * This is to cancel the background timer for the physical timer * emulation if it is set. */ - soft_timer_cancel(&timer->bg_timer, &timer->expired); + soft_timer_cancel(&timer->phys_timer, NULL); /* * The guest could have modified the timer registers or the timer @@ -507,6 +513,9 @@ void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu) hrtimer_init(&timer->bg_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); timer->bg_timer.function = kvm_bg_timer_expire; + hrtimer_init(&timer->phys_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); + timer->phys_timer.function = kvm_phys_timer_expire; + vtimer->irq.irq = default_vtimer_irq.irq; ptimer->irq.irq = default_ptimer_irq.irq; } @@ -615,6 +624,7 @@ void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu) struct arch_timer_context *vtimer = vcpu_vtimer(vcpu); soft_timer_cancel(&timer->bg_timer, &timer->expired); + soft_timer_cancel(&timer->phys_timer, NULL); kvm_vgic_unmap_phys_irq(vcpu, vtimer->irq.irq); }