From patchwork Fri Aug 1 09:17:35 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Graf X-Patchwork-Id: 4661891 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 25C3F9F319 for ; Fri, 1 Aug 2014 09:22:25 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 5DC5E201DD for ; Fri, 1 Aug 2014 09:22:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7712A2010E for ; Fri, 1 Aug 2014 09:22:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754196AbaHAJSh (ORCPT ); Fri, 1 Aug 2014 05:18:37 -0400 Received: from cantor2.suse.de ([195.135.220.15]:49793 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751723AbaHAJSg (ORCPT ); Fri, 1 Aug 2014 05:18:36 -0400 Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 2D0F675028; Fri, 1 Aug 2014 09:18:35 +0000 (UTC) From: Alexander Graf To: kvm-ppc@vger.kernel.org Cc: kvm@vger.kernel.org Subject: [PULL 04/63] KVM: PPC: Book3s PR: Disable AIL mode with OPAL Date: Fri, 1 Aug 2014 11:17:35 +0200 Message-Id: <1406884714-33099-5-git-send-email-agraf@suse.de> X-Mailer: git-send-email 1.8.1.4 In-Reply-To: <1406884714-33099-1-git-send-email-agraf@suse.de> References: <1406884714-33099-1-git-send-email-agraf@suse.de> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-7.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When we're using PR KVM we must not allow the CPU to take interrupts in virtual mode, as the SLB does not contain host kernel mappings when running inside the guest context. To make sure we get good performance for non-KVM tasks but still properly functioning PR KVM, let's just disable AIL whenever a vcpu is scheduled in. This is fundamentally different from how we deal with AIL on pSeries type machines where we disable AIL for the whole machine as soon as a single KVM VM is up. The reason for that is easy - on pSeries we do not have control over per-cpu configuration of AIL. We also don't want to mess with CPU hotplug races and AIL configuration, so setting it per CPU is easier and more flexible. This patch fixes running PR KVM on POWER8 bare metal for me. Signed-off-by: Alexander Graf Acked-by: Paul Mackerras --- arch/powerpc/kvm/book3s_pr.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index 3da412e..8ea7da4 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -71,6 +71,12 @@ static void kvmppc_core_vcpu_load_pr(struct kvm_vcpu *vcpu, int cpu) svcpu->in_use = 0; svcpu_put(svcpu); #endif + + /* Disable AIL if supported */ + if (cpu_has_feature(CPU_FTR_HVMODE) && + cpu_has_feature(CPU_FTR_ARCH_207S)) + mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) & ~LPCR_AIL); + vcpu->cpu = smp_processor_id(); #ifdef CONFIG_PPC_BOOK3S_32 current->thread.kvm_shadow_vcpu = vcpu->arch.shadow_vcpu; @@ -91,6 +97,12 @@ static void kvmppc_core_vcpu_put_pr(struct kvm_vcpu *vcpu) kvmppc_giveup_ext(vcpu, MSR_FP | MSR_VEC | MSR_VSX); kvmppc_giveup_fac(vcpu, FSCR_TAR_LG); + + /* Enable AIL if supported */ + if (cpu_has_feature(CPU_FTR_HVMODE) && + cpu_has_feature(CPU_FTR_ARCH_207S)) + mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) | LPCR_AIL_3); + vcpu->cpu = -1; }