From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: [PATCH 3/4 V9] Add ioctl for KVMCLOCK_GUEST_STOPPED Date: Tue, 17 Jan 2012 19:20:19 +0100 Message-ID: <4F15BBE3.4090800@siemens.com> References: <1326823488-11413-1-git-send-email-emunson@mgebm.net> <1326823488-11413-4-git-send-email-emunson@mgebm.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1326823488-11413-4-git-send-email-emunson@mgebm.net> Sender: linux-kernel-owner@vger.kernel.org To: Eric B Munson Cc: avi@redhat.com, mingo@redhat.com, hpa@zytor.com, ryanh@linux.vnet.ibm.com, aliguori@us.ibm.com, mtosatti@redhat.com, jeremy.fitzhardinge@citrix.com, kvm@vger.kernel.org, linux-arch@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org List-Id: linux-arch.vger.kernel.org On 2012-01-17 19:04, Eric B Munson wrote: > Now that we have a flag that will tell the guest it was suspended, create an > interface for that communication using a KVM ioctl. > > Signed-off-by: Eric B Munson > > Cc: mingo@redhat.com > Cc: hpa@zytor.com > Cc: ryanh@linux.vnet.ibm.com > Cc: aliguori@us.ibm.com > Cc: mtosatti@redhat.com > Cc: jeremy.fitzhardinge@citrix.com > Cc: kvm@vger.kernel.org > Cc: linux-arch@vger.kernel.org > Cc: x86@kernel.org > Cc: linux-kernel@vger.kernel.org > --- > Changes from V8: > Make KVM_GUEST_PAUSED a per vm ioctl instead of per vcpu > > Changes from V7: > Define KVM_CAP_GUEST_PAUSED and support check > Call mark_page_dirty () after setting PVCLOCK_GUEST_STOPPED > > Changes from V4: > Rename KVM_GUEST_PAUSED to KVMCLOCK_GUEST_PAUSED > Add new ioctl description to api.txt > > Documentation/virtual/kvm/api.txt | 13 +++++++++++++ > arch/x86/kvm/x86.c | 26 ++++++++++++++++++++++++++ > include/linux/kvm.h | 3 +++ > 3 files changed, 42 insertions(+), 0 deletions(-) > > diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt > index e1d94bf..1931e5c 100644 > --- a/Documentation/virtual/kvm/api.txt > +++ b/Documentation/virtual/kvm/api.txt > @@ -1491,6 +1491,19 @@ following algorithm: > Some guests configure the LINT1 NMI input to cause a panic, aiding in > debugging. > > +4.65 KVMCLOCK_GUEST_PAUSED > + > +Capability: KVM_CAP_GUEST_PAUSED > +Architechtures: Any that implement pvclocks (currently x86 only) > +Type: vcpu ioctl > +Parameters: None > +Returns: 0 on success, -1 on error > + > +This signals to the host kernel that the specified guest is being paused by > +userspace. The host will set a flag in the pvclock structure that is checked > +from the soft lockup watchdog. This ioctl can be called during pause or > +unpause. > + > 5. The kvm_run structure > > Application code obtains a pointer to the kvm_run structure by > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 14d6cad..4661abe 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -2056,6 +2056,7 @@ int kvm_dev_ioctl_check_extension(long ext) > case KVM_CAP_X86_ROBUST_SINGLESTEP: > case KVM_CAP_XSAVE: > case KVM_CAP_ASYNC_PF: > + case KVM_CAP_GUEST_PAUSED: > case KVM_CAP_GET_TSC_KHZ: > r = 1; > break; > @@ -3061,6 +3062,27 @@ out: > return r; > } > > +/* > + * kvm_set_guest_paused() indicates to the guest kernel that it has been > + * stopped by the hypervisor. This function will be called from the host only. > + */ > +static int kvm_set_guest_paused(struct kvm *kvm) > +{ > + struct kvm_vcpu *vcpu; > + struct pvclock_vcpu_time_info *src; > + int i; > + > + for (i = 0; i < atomic_read(&kvm->online_vcpus); i++) { > + vcpu = kvm->vcpus[i]; kvm_for_each_vcpu? > + if (!vcpu->arch.time_page) > + continue; > + src = &vcpu->arch.hv_clock; > + src->flags |= PVCLOCK_GUEST_STOPPED; > + mark_page_dirty(vcpu->kvm, vcpu->arch.time >> PAGE_SHIFT); > + } > + return 0; > +} > + > long kvm_arch_vm_ioctl(struct file *filp, > unsigned int ioctl, unsigned long arg) > { > @@ -3351,6 +3373,10 @@ long kvm_arch_vm_ioctl(struct file *filp, > r = 0; > break; > } > + case KVMCLOCK_GUEST_PAUSED: { > + r = kvm_set_guest_paused(kvm); > + break; > + } > > default: > ; > diff --git a/include/linux/kvm.h b/include/linux/kvm.h > index 68e67e5..4ffe0df 100644 > --- a/include/linux/kvm.h > +++ b/include/linux/kvm.h > @@ -558,6 +558,7 @@ struct kvm_ppc_pvinfo { > #define KVM_CAP_PPC_PAPR 68 > #define KVM_CAP_S390_GMAP 71 > #define KVM_CAP_TSC_DEADLINE_TIMER 72 > +#define KVM_CAP_GUEST_PAUSED 73 > > #ifdef KVM_CAP_IRQ_ROUTING > > @@ -763,6 +764,8 @@ struct kvm_clock_data { > #define KVM_CREATE_SPAPR_TCE _IOW(KVMIO, 0xa8, struct kvm_create_spapr_tce) > /* Available with KVM_CAP_RMA */ > #define KVM_ALLOCATE_RMA _IOR(KVMIO, 0xa9, struct kvm_allocate_rma) > +/* VM is being stopped by host */ > +#define KVMCLOCK_GUEST_PAUSED _IO(KVMIO, 0xaa) > > #define KVM_DEV_ASSIGN_ENABLE_IOMMU (1 << 0) > Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from david.siemens.de ([192.35.17.14]:21659 "EHLO david.siemens.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754672Ab2AQSo3 (ORCPT ); Tue, 17 Jan 2012 13:44:29 -0500 Message-ID: <4F15BBE3.4090800@siemens.com> Date: Tue, 17 Jan 2012 19:20:19 +0100 From: Jan Kiszka MIME-Version: 1.0 Subject: Re: [PATCH 3/4 V9] Add ioctl for KVMCLOCK_GUEST_STOPPED References: <1326823488-11413-1-git-send-email-emunson@mgebm.net> <1326823488-11413-4-git-send-email-emunson@mgebm.net> In-Reply-To: <1326823488-11413-4-git-send-email-emunson@mgebm.net> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Sender: linux-arch-owner@vger.kernel.org List-ID: To: Eric B Munson Cc: avi@redhat.com, mingo@redhat.com, hpa@zytor.com, ryanh@linux.vnet.ibm.com, aliguori@us.ibm.com, mtosatti@redhat.com, jeremy.fitzhardinge@citrix.com, kvm@vger.kernel.org, linux-arch@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org Message-ID: <20120117182019.W3-B8Ub-5_U2jlnCqEEu6HhYKukDTQSG1RgIvFHaHzE@z> On 2012-01-17 19:04, Eric B Munson wrote: > Now that we have a flag that will tell the guest it was suspended, create an > interface for that communication using a KVM ioctl. > > Signed-off-by: Eric B Munson > > Cc: mingo@redhat.com > Cc: hpa@zytor.com > Cc: ryanh@linux.vnet.ibm.com > Cc: aliguori@us.ibm.com > Cc: mtosatti@redhat.com > Cc: jeremy.fitzhardinge@citrix.com > Cc: kvm@vger.kernel.org > Cc: linux-arch@vger.kernel.org > Cc: x86@kernel.org > Cc: linux-kernel@vger.kernel.org > --- > Changes from V8: > Make KVM_GUEST_PAUSED a per vm ioctl instead of per vcpu > > Changes from V7: > Define KVM_CAP_GUEST_PAUSED and support check > Call mark_page_dirty () after setting PVCLOCK_GUEST_STOPPED > > Changes from V4: > Rename KVM_GUEST_PAUSED to KVMCLOCK_GUEST_PAUSED > Add new ioctl description to api.txt > > Documentation/virtual/kvm/api.txt | 13 +++++++++++++ > arch/x86/kvm/x86.c | 26 ++++++++++++++++++++++++++ > include/linux/kvm.h | 3 +++ > 3 files changed, 42 insertions(+), 0 deletions(-) > > diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt > index e1d94bf..1931e5c 100644 > --- a/Documentation/virtual/kvm/api.txt > +++ b/Documentation/virtual/kvm/api.txt > @@ -1491,6 +1491,19 @@ following algorithm: > Some guests configure the LINT1 NMI input to cause a panic, aiding in > debugging. > > +4.65 KVMCLOCK_GUEST_PAUSED > + > +Capability: KVM_CAP_GUEST_PAUSED > +Architechtures: Any that implement pvclocks (currently x86 only) > +Type: vcpu ioctl > +Parameters: None > +Returns: 0 on success, -1 on error > + > +This signals to the host kernel that the specified guest is being paused by > +userspace. The host will set a flag in the pvclock structure that is checked > +from the soft lockup watchdog. This ioctl can be called during pause or > +unpause. > + > 5. The kvm_run structure > > Application code obtains a pointer to the kvm_run structure by > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 14d6cad..4661abe 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -2056,6 +2056,7 @@ int kvm_dev_ioctl_check_extension(long ext) > case KVM_CAP_X86_ROBUST_SINGLESTEP: > case KVM_CAP_XSAVE: > case KVM_CAP_ASYNC_PF: > + case KVM_CAP_GUEST_PAUSED: > case KVM_CAP_GET_TSC_KHZ: > r = 1; > break; > @@ -3061,6 +3062,27 @@ out: > return r; > } > > +/* > + * kvm_set_guest_paused() indicates to the guest kernel that it has been > + * stopped by the hypervisor. This function will be called from the host only. > + */ > +static int kvm_set_guest_paused(struct kvm *kvm) > +{ > + struct kvm_vcpu *vcpu; > + struct pvclock_vcpu_time_info *src; > + int i; > + > + for (i = 0; i < atomic_read(&kvm->online_vcpus); i++) { > + vcpu = kvm->vcpus[i]; kvm_for_each_vcpu? > + if (!vcpu->arch.time_page) > + continue; > + src = &vcpu->arch.hv_clock; > + src->flags |= PVCLOCK_GUEST_STOPPED; > + mark_page_dirty(vcpu->kvm, vcpu->arch.time >> PAGE_SHIFT); > + } > + return 0; > +} > + > long kvm_arch_vm_ioctl(struct file *filp, > unsigned int ioctl, unsigned long arg) > { > @@ -3351,6 +3373,10 @@ long kvm_arch_vm_ioctl(struct file *filp, > r = 0; > break; > } > + case KVMCLOCK_GUEST_PAUSED: { > + r = kvm_set_guest_paused(kvm); > + break; > + } > > default: > ; > diff --git a/include/linux/kvm.h b/include/linux/kvm.h > index 68e67e5..4ffe0df 100644 > --- a/include/linux/kvm.h > +++ b/include/linux/kvm.h > @@ -558,6 +558,7 @@ struct kvm_ppc_pvinfo { > #define KVM_CAP_PPC_PAPR 68 > #define KVM_CAP_S390_GMAP 71 > #define KVM_CAP_TSC_DEADLINE_TIMER 72 > +#define KVM_CAP_GUEST_PAUSED 73 > > #ifdef KVM_CAP_IRQ_ROUTING > > @@ -763,6 +764,8 @@ struct kvm_clock_data { > #define KVM_CREATE_SPAPR_TCE _IOW(KVMIO, 0xa8, struct kvm_create_spapr_tce) > /* Available with KVM_CAP_RMA */ > #define KVM_ALLOCATE_RMA _IOR(KVMIO, 0xa9, struct kvm_allocate_rma) > +/* VM is being stopped by host */ > +#define KVMCLOCK_GUEST_PAUSED _IO(KVMIO, 0xaa) > > #define KVM_DEV_ASSIGN_ENABLE_IOMMU (1 << 0) > Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux