From 6e1d13bf3815d6058620dd72135be292d9f44bc9 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Tue, 3 May 2022 09:52:48 -0700 Subject: [PATCH] KVM: selftests: Move per-VM/per-vCPU nr pages calculation to __vm_create() Handle all memslot0 size adjustments in __vm_create(). Currently, the adjustments reside in __vm_create_with_vcpus(), which means tests that call vm_create() or __vm_create() directly are left to their own devices. Some tests just pass DEFAULT_GUEST_PHY_PAGES and don't bother with any adjustments, while others mimic the per-vCPU calculations. For vm_create(), and thus __vm_create(), take the number of vCPUs that will be runnable to calculate that number of per-vCPU pages needed for memslot0. To give readers a hint that neither vm_create() nor __vm_create() create vCPUs, name the parameter @nr_runnable_vcpus instead of @nr_vcpus. That also gives readers a hint as to why tests that create larger numbers of vCPUs but never actually run those vCPUs can skip straight to the vm_create_barebones() variant. Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini --- tools/testing/selftests/kvm/aarch64/psci_test.c | 2 +- tools/testing/selftests/kvm/aarch64/vgic_init.c | 4 +- tools/testing/selftests/kvm/dirty_log_test.c | 3 +- .../testing/selftests/kvm/hardware_disable_test.c | 2 +- .../testing/selftests/kvm/include/kvm_util_base.h | 9 ++-- tools/testing/selftests/kvm/lib/kvm_util.c | 57 ++++++++++++++-------- tools/testing/selftests/kvm/s390x/resets.c | 2 +- .../selftests/kvm/x86_64/pmu_event_filter_test.c | 2 +- .../testing/selftests/kvm/x86_64/set_boot_cpu_id.c | 5 +- .../selftests/kvm/x86_64/tsc_scaling_sync.c | 2 +- 10 files changed, 53 insertions(+), 35 deletions(-) diff --git a/tools/testing/selftests/kvm/aarch64/psci_test.c b/tools/testing/selftests/kvm/aarch64/psci_test.c index 3e1bebe..7928c62 100644 --- a/tools/testing/selftests/kvm/aarch64/psci_test.c +++ b/tools/testing/selftests/kvm/aarch64/psci_test.c @@ -76,7 +76,7 @@ static struct kvm_vm *setup_vm(void *guest_code, struct kvm_vcpu **source, struct kvm_vcpu_init init; struct kvm_vm *vm; - vm = vm_create(DEFAULT_GUEST_PHY_PAGES); + vm = vm_create(2); ucall_init(vm, NULL); vm_ioctl(vm, KVM_ARM_PREFERRED_TARGET, &init); diff --git a/tools/testing/selftests/kvm/aarch64/vgic_init.c b/tools/testing/selftests/kvm/aarch64/vgic_init.c index 6b9c9a3..0240280 100644 --- a/tools/testing/selftests/kvm/aarch64/vgic_init.c +++ b/tools/testing/selftests/kvm/aarch64/vgic_init.c @@ -419,7 +419,7 @@ static void test_v3_typer_accesses(void) uint64_t addr; int ret, i; - v.vm = vm_create(DEFAULT_GUEST_PHY_PAGES); + v.vm = vm_create(NR_VCPUS); (void)vm_vcpu_add(v.vm, 0, guest_code); v.gic_fd = kvm_create_device(v.vm, KVM_DEV_TYPE_ARM_VGIC_V3); @@ -479,7 +479,7 @@ static struct vm_gic vm_gic_v3_create_with_vcpuids(int nr_vcpus, struct vm_gic v; int i; - v.vm = vm_create(DEFAULT_GUEST_PHY_PAGES); + v.vm = vm_create(nr_vcpus); for (i = 0; i < nr_vcpus; i++) vm_vcpu_add(v.vm, vcpuids[i], guest_code); diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c index ca584b9..8542f71 100644 --- a/tools/testing/selftests/kvm/dirty_log_test.c +++ b/tools/testing/selftests/kvm/dirty_log_test.c @@ -669,11 +669,10 @@ static struct kvm_vm *create_vm(enum vm_guest_mode mode, struct kvm_vcpu **vcpu, uint64_t extra_mem_pages, void *guest_code) { struct kvm_vm *vm; - uint64_t extra_pg_pages = extra_mem_pages / 512 * 2; pr_info("Testing guest mode: %s\n", vm_guest_mode_string(mode)); - vm = __vm_create(mode, DEFAULT_GUEST_PHY_PAGES + extra_pg_pages); + vm = __vm_create(mode, 1, extra_mem_pages); log_mode_create_vm_done(vm); *vcpu = vm_vcpu_add(vm, 0, guest_code); diff --git a/tools/testing/selftests/kvm/hardware_disable_test.c b/tools/testing/selftests/kvm/hardware_disable_test.c index 2401577..f5d59b9 100644 --- a/tools/testing/selftests/kvm/hardware_disable_test.c +++ b/tools/testing/selftests/kvm/hardware_disable_test.c @@ -98,7 +98,7 @@ static void run_test(uint32_t run) for (i = 0; i < VCPU_NUM; i++) CPU_SET(i, &cpu_set); - vm = vm_create(DEFAULT_GUEST_PHY_PAGES); + vm = vm_create(VCPU_NUM); pr_debug("%s: [%d] start vcpus\n", __func__, run); for (i = 0; i < VCPU_NUM; ++i) { diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h index 6143d45..db9c00a 100644 --- a/tools/testing/selftests/kvm/include/kvm_util_base.h +++ b/tools/testing/selftests/kvm/include/kvm_util_base.h @@ -547,18 +547,21 @@ vm_paddr_t vm_alloc_page_table(struct kvm_vm *vm); /* * ____vm_create() does KVM_CREATE_VM and little else. __vm_create() also * loads the test binary into guest memory and creates an IRQ chip (x86 only). + * __vm_create() does NOT create vCPUs, @nr_runnable_vcpus is used purely to + * calculate the amount of memory needed for per-vCPU data, e.g. stacks. */ struct kvm_vm *____vm_create(enum vm_guest_mode mode, uint64_t nr_pages); -struct kvm_vm *__vm_create(enum vm_guest_mode mode, uint64_t nr_pages); +struct kvm_vm *__vm_create(enum vm_guest_mode mode, uint32_t nr_runnable_vcpus, + uint64_t nr_extra_pages); static inline struct kvm_vm *vm_create_barebones(void) { return ____vm_create(VM_MODE_DEFAULT, 0); } -static inline struct kvm_vm *vm_create(uint64_t nr_pages) +static inline struct kvm_vm *vm_create(uint32_t nr_runnable_vcpus) { - return __vm_create(VM_MODE_DEFAULT, nr_pages); + return __vm_create(VM_MODE_DEFAULT, nr_runnable_vcpus, 0); } struct kvm_vm *__vm_create_with_vcpus(enum vm_guest_mode mode, uint32_t nr_vcpus, diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c index afefc48..620c355 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -258,11 +258,45 @@ struct kvm_vm *____vm_create(enum vm_guest_mode mode, uint64_t nr_pages) return vm; } -struct kvm_vm *__vm_create(enum vm_guest_mode mode, uint64_t nr_pages) +static uint64_t vm_nr_pages_required(enum vm_guest_mode mode, + uint32_t nr_runnable_vcpus, + uint64_t extra_mem_pages) { - struct kvm_vm *vm; + uint64_t nr_pages; + + TEST_ASSERT(nr_runnable_vcpus, + "Use vm_create_barebones() for VMs that _never_ have vCPUs\n"); + + TEST_ASSERT(nr_runnable_vcpus <= kvm_check_cap(KVM_CAP_MAX_VCPUS), + "nr_vcpus = %d too large for host, max-vcpus = %d", + nr_runnable_vcpus, kvm_check_cap(KVM_CAP_MAX_VCPUS)); + + nr_pages = DEFAULT_GUEST_PHY_PAGES; + nr_pages += nr_runnable_vcpus * DEFAULT_STACK_PGS; + + /* + * Account for the number of pages needed for the page tables. The + * maximum page table size for a memory region will be when the + * smallest page size is used. Considering each page contains x page + * table descriptors, the total extra size for page tables (for extra + * N pages) will be: N/x+N/x^2+N/x^3+... which is definitely smaller + * than N/x*2. + */ + nr_pages += (nr_pages + extra_mem_pages) / PTES_PER_MIN_PAGE * 2; - nr_pages = vm_adjust_num_guest_pages(mode, nr_pages); + TEST_ASSERT(nr_runnable_vcpus <= kvm_check_cap(KVM_CAP_MAX_VCPUS), + "Host doesn't support %d vCPUs, max-vcpus = %d", + nr_runnable_vcpus, kvm_check_cap(KVM_CAP_MAX_VCPUS)); + + return vm_adjust_num_guest_pages(mode, nr_pages); +} + +struct kvm_vm *__vm_create(enum vm_guest_mode mode, uint32_t nr_runnable_vcpus, + uint64_t nr_extra_pages) +{ + uint64_t nr_pages = vm_nr_pages_required(mode, nr_runnable_vcpus, + nr_extra_pages); + struct kvm_vm *vm; vm = ____vm_create(mode, nr_pages); @@ -297,27 +331,12 @@ struct kvm_vm *__vm_create_with_vcpus(enum vm_guest_mode mode, uint32_t nr_vcpus uint64_t extra_mem_pages, void *guest_code, struct kvm_vcpu *vcpus[]) { - uint64_t vcpu_pages, extra_pg_pages, pages; struct kvm_vm *vm; int i; TEST_ASSERT(!nr_vcpus || vcpus, "Must provide vCPU array"); - /* The maximum page table size for a memory region will be when the - * smallest pages are used. Considering each page contains x page - * table descriptors, the total extra size for page tables (for extra - * N pages) will be: N/x+N/x^2+N/x^3+... which is definitely smaller - * than N/x*2. - */ - vcpu_pages = nr_vcpus * DEFAULT_STACK_PGS; - extra_pg_pages = (DEFAULT_GUEST_PHY_PAGES + extra_mem_pages + vcpu_pages) / PTES_PER_MIN_PAGE * 2; - pages = DEFAULT_GUEST_PHY_PAGES + vcpu_pages + extra_pg_pages; - - TEST_ASSERT(nr_vcpus <= kvm_check_cap(KVM_CAP_MAX_VCPUS), - "nr_vcpus = %d too large for host, max-vcpus = %d", - nr_vcpus, kvm_check_cap(KVM_CAP_MAX_VCPUS)); - - vm = __vm_create(mode, pages); + vm = __vm_create(mode, nr_vcpus, extra_mem_pages); for (i = 0; i < nr_vcpus; ++i) vcpus[i] = vm_vcpu_add(vm, i, guest_code); diff --git a/tools/testing/selftests/kvm/s390x/resets.c b/tools/testing/selftests/kvm/s390x/resets.c index 633ba90..e173741 100644 --- a/tools/testing/selftests/kvm/s390x/resets.c +++ b/tools/testing/selftests/kvm/s390x/resets.c @@ -206,7 +206,7 @@ static struct kvm_vm *create_vm(struct kvm_vcpu **vcpu) { struct kvm_vm *vm; - vm = vm_create(DEFAULT_GUEST_PHY_PAGES); + vm = vm_create(1); *vcpu = vm_vcpu_add(vm, ARBITRARY_NON_ZERO_VCPU_ID, guest_code_initial); diff --git a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c index c86b84b..07fa68a 100644 --- a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c +++ b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c @@ -365,7 +365,7 @@ static void test_pmu_config_disable(void (*guest_code)(void)) if (!(r & KVM_PMU_CAP_DISABLE)) return; - vm = vm_create(DEFAULT_GUEST_PHY_PAGES); + vm = vm_create(1); vm_enable_cap(vm, KVM_CAP_PMU_CAPABILITY, KVM_PMU_CAP_DISABLE); diff --git a/tools/testing/selftests/kvm/x86_64/set_boot_cpu_id.c b/tools/testing/selftests/kvm/x86_64/set_boot_cpu_id.c index afc0631..8bcaf44 100644 --- a/tools/testing/selftests/kvm/x86_64/set_boot_cpu_id.c +++ b/tools/testing/selftests/kvm/x86_64/set_boot_cpu_id.c @@ -78,13 +78,10 @@ static void run_vcpu(struct kvm_vcpu *vcpu) static struct kvm_vm *create_vm(uint32_t nr_vcpus, uint32_t bsp_vcpu_id, struct kvm_vcpu *vcpus[]) { - uint64_t vcpu_pages = (DEFAULT_STACK_PGS) * nr_vcpus; - uint64_t extra_pg_pages = vcpu_pages / PTES_PER_MIN_PAGE * nr_vcpus; - uint64_t pages = DEFAULT_GUEST_PHY_PAGES + vcpu_pages + extra_pg_pages; struct kvm_vm *vm; uint32_t i; - vm = vm_create(pages); + vm = vm_create(nr_vcpus); vm_ioctl(vm, KVM_SET_BOOT_CPU_ID, (void *)(unsigned long)bsp_vcpu_id); diff --git a/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c b/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c index e416af8..4a96295 100644 --- a/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c +++ b/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c @@ -98,7 +98,7 @@ int main(int argc, char *argv[]) exit(KSFT_SKIP); } - vm = vm_create(DEFAULT_GUEST_PHY_PAGES + DEFAULT_STACK_PGS * NR_TEST_VCPUS); + vm = vm_create(NR_TEST_VCPUS); vm_ioctl(vm, KVM_SET_TSC_KHZ, (void *) TEST_TSC_KHZ); pthread_spin_init(&create_lock, PTHREAD_PROCESS_PRIVATE); -- 2.7.4