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Diffstat (limited to '')
| -rw-r--r-- | tools/testing/selftests/kvm/lib/x86_64/perf_test_util.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/lib/x86_64/perf_test_util.c b/tools/testing/selftests/kvm/lib/x86_64/perf_test_util.c new file mode 100644 index 000000000000..0f344a7c89c4 --- /dev/null +++ b/tools/testing/selftests/kvm/lib/x86_64/perf_test_util.c @@ -0,0 +1,111 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * x86_64-specific extensions to perf_test_util.c. + * + * Copyright (C) 2022, Google, Inc. + */ +#include <stdio.h> +#include <stdlib.h> +#include <linux/bitmap.h> +#include <linux/bitops.h> + +#include "test_util.h" +#include "kvm_util.h" +#include "perf_test_util.h" +#include "processor.h" +#include "vmx.h" + +void perf_test_l2_guest_code(uint64_t vcpu_id) +{ + perf_test_guest_code(vcpu_id); + vmcall(); +} + +extern char perf_test_l2_guest_entry[]; +__asm__( +"perf_test_l2_guest_entry:" +" mov (%rsp), %rdi;" +" call perf_test_l2_guest_code;" +" ud2;" +); + +static void perf_test_l1_guest_code(struct vmx_pages *vmx, uint64_t vcpu_id) +{ +#define L2_GUEST_STACK_SIZE 64 + unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE]; + unsigned long *rsp; + + GUEST_ASSERT(vmx->vmcs_gpa); + GUEST_ASSERT(prepare_for_vmx_operation(vmx)); + GUEST_ASSERT(load_vmcs(vmx)); + GUEST_ASSERT(ept_1g_pages_supported()); + + rsp = &l2_guest_stack[L2_GUEST_STACK_SIZE - 1]; + *rsp = vcpu_id; + prepare_vmcs(vmx, perf_test_l2_guest_entry, rsp); + + GUEST_ASSERT(!vmlaunch()); + GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL); + GUEST_DONE(); +} + +uint64_t perf_test_nested_pages(int nr_vcpus) +{ + /* + * 513 page tables is enough to identity-map 256 TiB of L2 with 1G + * pages and 4-level paging, plus a few pages per-vCPU for data + * structures such as the VMCS. + */ + return 513 + 10 * nr_vcpus; +} + +void perf_test_setup_ept(struct vmx_pages *vmx, struct kvm_vm *vm) +{ + uint64_t start, end; + + prepare_eptp(vmx, vm, 0); + + /* + * Identity map the first 4G and the test region with 1G pages so that + * KVM can shadow the EPT12 with the maximum huge page size supported + * by the backing source. + */ + nested_identity_map_1g(vmx, vm, 0, 0x100000000ULL); + + start = align_down(perf_test_args.gpa, PG_SIZE_1G); + end = align_up(perf_test_args.gpa + perf_test_args.size, PG_SIZE_1G); + nested_identity_map_1g(vmx, vm, start, end - start); +} + +void perf_test_setup_nested(struct kvm_vm *vm, int nr_vcpus, struct kvm_vcpu *vcpus[]) +{ + struct vmx_pages *vmx, *vmx0 = NULL; + struct kvm_regs regs; + vm_vaddr_t vmx_gva; + int vcpu_id; + + TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX)); + + for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) { + vmx = vcpu_alloc_vmx(vm, &vmx_gva); + + if (vcpu_id == 0) { + perf_test_setup_ept(vmx, vm); + vmx0 = vmx; + } else { + /* Share the same EPT table across all vCPUs. */ + vmx->eptp = vmx0->eptp; + vmx->eptp_hva = vmx0->eptp_hva; + vmx->eptp_gpa = vmx0->eptp_gpa; + } + + /* + * Override the vCPU to run perf_test_l1_guest_code() which will + * bounce it into L2 before calling perf_test_guest_code(). + */ + vcpu_regs_get(vcpus[vcpu_id], ®s); + regs.rip = (unsigned long) perf_test_l1_guest_code; + vcpu_regs_set(vcpus[vcpu_id], ®s); + vcpu_args_set(vcpus[vcpu_id], 2, vmx_gva, vcpu_id); + } +} |