From mboxrd@z Thu Jan 1 00:00:00 1970 From: Raghavendra K T Subject: Re: [PATCH RFC V10 16/18] kvm hypervisor : Simplify kvm_for_each_vcpu with kvm_irq_delivery_to_apic Date: Mon, 15 Jul 2013 21:06:13 +0530 Message-ID: <51E416ED.3090604@linux.vnet.ibm.com> References: <20130624124014.27508.8906.sendpatchset@codeblue.in.ibm.com> <20130624124353.27508.94224.sendpatchset@codeblue.in.ibm.com> <20130714132402.GB11772@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20130714132402.GB11772@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Gleb Natapov Cc: jeremy@goop.org, gregkh@suse.de, kvm@vger.kernel.org, linux-doc@vger.kernel.org, peterz@infradead.org, drjones@redhat.com, virtualization@lists.linux-foundation.org, andi@firstfloor.org, hpa@zytor.com, stefano.stabellini@eu.citrix.com, xen-devel@lists.xensource.com, x86@kernel.org, mingo@redhat.com, habanero@linux.vnet.ibm.com, riel@redhat.com, konrad.wilk@oracle.com, ouyang@cs.pitt.edu, avi.kivity@gmail.com, tglx@linutronix.de, chegu_vinod@hp.com, linux-kernel@vger.kernel.org, srivatsa.vaddagiri@gmail.com, attilio.rao@citrix.com, pbonzini@redhat.com, torvalds@linux-foundation.org, stephan.diestelhorst@amd.com List-Id: xen-devel@lists.xenproject.org On 07/14/2013 06:54 PM, Gleb Natapov wrote: > On Mon, Jun 24, 2013 at 06:13:53PM +0530, Raghavendra K T wrote: >> Simplify kvm_for_each_vcpu with kvm_irq_delivery_to_apic >> >> From: Raghavendra K T >> >> Note that we are using APIC_DM_REMRD which has reserved usage. >> In future if APIC_DM_REMRD usage is standardized, then we should >> find some other way or go back to old method. >> >> Suggested-by: Gleb Natapov >> Signed-off-by: Raghavendra K T >> --- >> arch/x86/kvm/lapic.c | 5 ++++- >> arch/x86/kvm/x86.c | 25 ++++++------------------- >> 2 files changed, 10 insertions(+), 20 deletions(-) >> >> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c >> index e1adbb4..3f5f82e 100644 >> --- a/arch/x86/kvm/lapic.c >> +++ b/arch/x86/kvm/lapic.c >> @@ -706,7 +706,10 @@ out: >> break; >> >> case APIC_DM_REMRD: >> - apic_debug("Ignoring delivery mode 3\n"); >> + result = 1; >> + vcpu->arch.pv.pv_unhalted = 1; >> + kvm_make_request(KVM_REQ_EVENT, vcpu); >> + kvm_vcpu_kick(vcpu); >> break; >> >> case APIC_DM_SMI: >> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c >> index 92a9932..b963c86 100644 >> --- a/arch/x86/kvm/x86.c >> +++ b/arch/x86/kvm/x86.c >> @@ -5456,27 +5456,14 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu) >> */ >> static void kvm_pv_kick_cpu_op(struct kvm *kvm, int apicid) >> { >> - struct kvm_vcpu *vcpu = NULL; >> - int i; >> + struct kvm_lapic_irq lapic_irq; >> >> - kvm_for_each_vcpu(i, vcpu, kvm) { >> - if (!kvm_apic_present(vcpu)) >> - continue; >> + lapic_irq.shorthand = 0; >> + lapic_irq.dest_mode = 0; >> + lapic_irq.dest_id = apicid; >> >> - if (kvm_apic_match_dest(vcpu, 0, 0, apicid, 0)) >> - break; >> - } >> - if (vcpu) { >> - /* >> - * Setting unhalt flag here can result in spurious runnable >> - * state when unhalt reset does not happen in vcpu_block. >> - * But that is harmless since that should soon result in halt. >> - */ >> - vcpu->arch.pv.pv_unhalted = true; >> - /* We need everybody see unhalt before vcpu unblocks */ >> - smp_wmb(); >> - kvm_vcpu_kick(vcpu); >> - } >> + lapic_irq.delivery_mode = APIC_DM_REMRD; > Need to make sure that delivery_mode cannot be set to APIC_DM_REMRD > from MSI/IOAPIC/IPI path. I Gleb, I need your help here since I do not know much about apic. so are you saying explicitly checking that, kvm_set_msi_irq, apic_send_ipi, native_setup_ioapic_entry, does not have APIC_DM_REMRD as delivery_mode set?