From patchwork Mon May 18 16:56:04 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marcelo Tosatti X-Patchwork-Id: 24604 Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n4IHC6wv000633 for ; Mon, 18 May 2009 17:12:07 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751722AbZERRLw (ORCPT ); Mon, 18 May 2009 13:11:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750930AbZERRLw (ORCPT ); Mon, 18 May 2009 13:11:52 -0400 Received: from mx2.redhat.com ([66.187.237.31]:55603 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750934AbZERRLu (ORCPT ); Mon, 18 May 2009 13:11:50 -0400 Received: from int-mx2.corp.redhat.com (int-mx2.corp.redhat.com [172.16.27.26]) by mx2.redhat.com (8.13.8/8.13.8) with ESMTP id n4IHBqOU010270 for ; Mon, 18 May 2009 13:11:52 -0400 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx2.corp.redhat.com (8.13.1/8.13.1) with ESMTP id n4IHBpMY018638; Mon, 18 May 2009 13:11:51 -0400 Received: from amt.cnet (vpn-10-172.str.redhat.com [10.32.10.172]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id n4IHBnLh017738; Mon, 18 May 2009 13:11:50 -0400 Received: from amt.cnet (amt.cnet [127.0.0.1]) by amt.cnet (Postfix) with ESMTP id 01A19274E1F; Mon, 18 May 2009 14:11:10 -0300 (BRT) Received: (from marcelo@localhost) by amt.cnet (8.14.3/8.14.3/Submit) id n4IHB8pe014684; Mon, 18 May 2009 14:11:08 -0300 Message-Id: <20090518170855.484310662@localhost.localdomain> References: <20090518165601.747763120@localhost.localdomain> User-Agent: quilt/0.46-1 Date: Mon, 18 May 2009 13:56:04 -0300 From: Marcelo Tosatti To: kvm@vger.kernel.org Cc: Marcelo Tosatti Subject: [patch 3/4] KVM: introduce irq_lock, use it protect ioapic Content-Disposition: inline; filename=ioapic-lock X-Scanned-By: MIMEDefang 2.58 on 172.16.27.26 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Signed-off-by: Marcelo Tosatti Index: kvm/include/linux/kvm_host.h =================================================================== --- kvm.orig/include/linux/kvm_host.h +++ kvm/include/linux/kvm_host.h @@ -123,7 +123,6 @@ struct kvm_kernel_irq_routing_entry { }; struct kvm { - struct mutex lock; /* protects the vcpus array and APIC accesses */ spinlock_t mmu_lock; struct rw_semaphore slots_lock; struct mm_struct *mm; /* userspace tied to this vm */ @@ -132,6 +131,12 @@ struct kvm { KVM_PRIVATE_MEM_SLOTS]; struct kvm_vcpu *vcpus[KVM_MAX_VCPUS]; struct list_head vm_list; + struct mutex lock; /* + * - protects mmio_bus, pio_bus. + * - protects a few concurrent ioctl's (FIXME). + * - protects concurrent create_vcpu, but + * kvm->vcpus walkers do it locklessly (FIXME). + */ struct kvm_io_bus mmio_bus; struct kvm_io_bus pio_bus; struct kvm_vm_stat stat; @@ -142,6 +147,7 @@ struct kvm { struct kvm_coalesced_mmio_ring *coalesced_mmio_ring; #endif + struct mutex irq_lock; /* protects high level irq logic, ioapic */ #ifdef CONFIG_HAVE_KVM_IRQCHIP struct list_head irq_routing; /* of kvm_kernel_irq_routing_entry */ struct hlist_head mask_notifier_list; Index: kvm/virt/kvm/ioapic.c =================================================================== --- kvm.orig/virt/kvm/ioapic.c +++ kvm/virt/kvm/ioapic.c @@ -225,6 +225,10 @@ static int ioapic_in_range(struct kvm_io { struct kvm_ioapic *ioapic = (struct kvm_ioapic *)this->private; + /* + * Lockless check for ioapic->base_address on the hazy assumption + * it does not change during the lifetime of a VM. + */ return ((addr >= ioapic->base_address && (addr < ioapic->base_address + IOAPIC_MEM_LENGTH))); } @@ -238,6 +242,7 @@ static void ioapic_mmio_read(struct kvm_ ioapic_debug("addr %lx\n", (unsigned long)addr); ASSERT(!(addr & 0xf)); /* check alignment */ + mutex_lock(&ioapic->kvm->irq_lock); addr &= 0xff; switch (addr) { case IOAPIC_REG_SELECT: @@ -264,6 +269,7 @@ static void ioapic_mmio_read(struct kvm_ default: printk(KERN_WARNING "ioapic: wrong length %d\n", len); } + mutex_unlock(&ioapic->kvm->irq_lock); } static void ioapic_mmio_write(struct kvm_io_device *this, gpa_t addr, int len, @@ -275,6 +281,8 @@ static void ioapic_mmio_write(struct kvm ioapic_debug("ioapic_mmio_write addr=%p len=%d val=%p\n", (void*)addr, len, val); ASSERT(!(addr & 0xf)); /* check alignment */ + + mutex_lock(&ioapic->kvm->irq_lock); if (len == 4 || len == 8) data = *(u32 *) val; else { @@ -300,6 +308,7 @@ static void ioapic_mmio_write(struct kvm default: break; } + mutex_unlock(&ioapic->kvm->irq_lock); } void kvm_ioapic_reset(struct kvm_ioapic *ioapic) Index: kvm/virt/kvm/kvm_main.c =================================================================== --- kvm.orig/virt/kvm/kvm_main.c +++ kvm/virt/kvm/kvm_main.c @@ -984,6 +984,7 @@ static struct kvm *kvm_create_vm(void) spin_lock_init(&kvm->mmu_lock); kvm_io_bus_init(&kvm->pio_bus); mutex_init(&kvm->lock); + mutex_init(&kvm->irq_lock); kvm_io_bus_init(&kvm->mmio_bus); init_rwsem(&kvm->slots_lock); atomic_set(&kvm->users_count, 1);