From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39252) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bFLKu-0004Zx-BW for qemu-devel@nongnu.org; Tue, 21 Jun 2016 09:03:35 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bFLKi-0007h5-5R for qemu-devel@nongnu.org; Tue, 21 Jun 2016 09:03:23 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:10087 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bFLKi-0007gp-0S for qemu-devel@nongnu.org; Tue, 21 Jun 2016 09:03:12 -0400 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id u5LCxN6E004177 for ; Tue, 21 Jun 2016 09:03:11 -0400 Received: from e06smtp17.uk.ibm.com (e06smtp17.uk.ibm.com [195.75.94.113]) by mx0b-001b2d01.pphosted.com with ESMTP id 23n2ekuaxw-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 21 Jun 2016 09:03:11 -0400 Received: from localhost by e06smtp17.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 21 Jun 2016 14:03:09 +0100 Received: from b06cxnps4074.portsmouth.uk.ibm.com (d06relay11.portsmouth.uk.ibm.com [9.149.109.196]) by d06dlp03.portsmouth.uk.ibm.com (Postfix) with ESMTP id 07F931B08067 for ; Tue, 21 Jun 2016 14:04:18 +0100 (BST) Received: from d06av10.portsmouth.uk.ibm.com (d06av10.portsmouth.uk.ibm.com [9.149.37.251]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u5LD36VH23658788 for ; Tue, 21 Jun 2016 13:03:06 GMT Received: from d06av10.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av10.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u5LC38QD018086 for ; Tue, 21 Jun 2016 06:03:08 -0600 From: David Hildenbrand Date: Tue, 21 Jun 2016 15:02:27 +0200 In-Reply-To: <1466514153-85777-1-git-send-email-dahi@linux.vnet.ibm.com> References: <1466514153-85777-1-git-send-email-dahi@linux.vnet.ibm.com> Message-Id: <1466514153-85777-23-git-send-email-dahi@linux.vnet.ibm.com> Subject: [Qemu-devel] [RFC 22/28] s390x/kvm: let the CPU model control CMM(A) List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: ehabkost@redhat.com, jdenemar@redhat.com, imammedo@redhat.com, cornelia.huck@de.ibm.com, borntraeger@de.ibm.com, fiuczy@linux.vnet.ibm.com, mimu@linux.vnet.ibm.com Starting with recent kernels, if the cmma attributes are available, we actually have hardware support. Enabling CMMA then means providing the guest VCPU with CMM, therefore enabling its CMM facility. Let's not blindly enable CMM anymore but let's control it using CPU models. For disabled CPU models, CMMA will continue to always get enabled. Also enable it in the applicable default models. Please note that CMM doesn't work with hugetlbfs, therefore we will warn the user and keep it disabled. Migrating from/to a hugetlbfs configuration works, as it will be disabled on both sides. Acked-by: Cornelia Huck Signed-off-by: David Hildenbrand --- target-s390x/gen-features.c | 1 + target-s390x/kvm.c | 47 ++++++++++++++++++++++++++++++++++----------- 2 files changed, 37 insertions(+), 11 deletions(-) diff --git a/target-s390x/gen-features.c b/target-s390x/gen-features.c index d4f4b29..52d46dc 100644 --- a/target-s390x/gen-features.c +++ b/target-s390x/gen-features.c @@ -371,6 +371,7 @@ static uint16_t full_GEN13_GA1[] = { #define default_GEN8_GA5 EmptyFeat static uint16_t default_GEN9_GA1[] = { S390_FEAT_GROUP_MSA_EXT_1, + S390_FEAT_CMM, }; #define default_GEN9_GA2 EmptyFeat #define default_GEN9_GA3 EmptyFeat diff --git a/target-s390x/kvm.c b/target-s390x/kvm.c index a4f5762..dd2abec 100644 --- a/target-s390x/kvm.c +++ b/target-s390x/kvm.c @@ -174,6 +174,18 @@ int kvm_s390_set_mem_limit(KVMState *s, uint64_t new_limit, uint64_t *hw_limit) return kvm_vm_ioctl(s, KVM_SET_DEVICE_ATTR, &attr); } +static bool kvm_s390_cmma_available(void) +{ + static bool initialized, value; + + if (!initialized) { + initialized = true; + value = kvm_vm_check_mem_attr(kvm_state, KVM_S390_VM_MEM_ENABLE_CMMA) && + kvm_vm_check_mem_attr(kvm_state, KVM_S390_VM_MEM_CLR_CMMA); + } + return value; +} + void kvm_s390_cmma_reset(void) { int rc; @@ -182,11 +194,15 @@ void kvm_s390_cmma_reset(void) .attr = KVM_S390_VM_MEM_CLR_CMMA, }; + if (!mem_path || !kvm_s390_cmma_available()) { + return; + } + rc = kvm_vm_ioctl(kvm_state, KVM_SET_DEVICE_ATTR, &attr); trace_kvm_clear_cmma(rc); } -static void kvm_s390_enable_cmma(KVMState *s) +static void kvm_s390_enable_cmma(void) { int rc; struct kvm_device_attr attr = { @@ -194,12 +210,7 @@ static void kvm_s390_enable_cmma(KVMState *s) .attr = KVM_S390_VM_MEM_ENABLE_CMMA, }; - if (!kvm_vm_check_mem_attr(s, KVM_S390_VM_MEM_ENABLE_CMMA) || - !kvm_vm_check_mem_attr(s, KVM_S390_VM_MEM_CLR_CMMA)) { - return; - } - - rc = kvm_vm_ioctl(s, KVM_SET_DEVICE_ATTR, &attr); + rc = kvm_vm_ioctl(kvm_state, KVM_SET_DEVICE_ATTR, &attr); trace_kvm_enable_cmma(rc); } @@ -259,10 +270,6 @@ int kvm_arch_init(MachineState *ms, KVMState *s) cap_mem_op = kvm_check_extension(s, KVM_CAP_S390_MEM_OP); cap_s390_irq = kvm_check_extension(s, KVM_CAP_S390_INJECT_IRQ); - if (!mem_path) { - kvm_s390_enable_cmma(s); - } - if (!kvm_check_extension(s, KVM_CAP_S390_GMAP) || !kvm_check_extension(s, KVM_CAP_S390_COW)) { phys_mem_set_alloc(legacy_s390_alloc); @@ -2509,6 +2516,11 @@ void kvm_s390_get_host_cpu_model(S390CPUModel *model, Error **errp) return; } + /* with cpu model support, CMM is only indicated if really available */ + if (kvm_s390_cmma_available()) { + set_bit(S390_FEAT_CMM, model->features); + } + if (s390_known_cpu_type(cpu_type)) { /* we want the exact model, even if some features are missing */ model->def = s390_find_cpu_def(cpu_type, ibc_gen(unblocked_ibc), @@ -2541,6 +2553,10 @@ void kvm_s390_apply_cpu_model(const S390CPUModel *model, Error **errp) int rc; if (!model) { + /* compatibility handling if cpu models are disabled */ + if (kvm_s390_cmma_available() && !mem_path) { + kvm_s390_enable_cmma(); + } return; } if (!kvm_s390_cpu_models_supported()) { @@ -2569,4 +2585,13 @@ void kvm_s390_apply_cpu_model(const S390CPUModel *model, Error **errp) error_setg(errp, "KVM: Error configuring CPU subfunctions: %d", rc); return; } + /* enable CMM via CMMA - disable on hugetlbfs */ + if (test_bit(S390_FEAT_CMM, model->features)) { + if (mem_path) { + error_report("Warning: CMM will not be enabled because it is not " + "compatible to hugetlbfs."); + } else { + kvm_s390_enable_cmma(); + } + } } -- 2.6.6