KVM: selftests: Factor code out of demand_paging_test (4b5d12b0) · Commits · 戴 / test

tools/testing/selftests/kvm/demand_paging_test.c

+23 −181

Original line number	Diff line number	Diff line
		@@ -21,18 +21,12 @@
		#include <linux/bitops.h>
		#include <linux/userfaultfd.h>

		#include "test_util.h"
		#include "kvm_util.h"
		#include "perf_test_util.h"
		#include "processor.h"
		#include "test_util.h"

		#ifdef __NR_userfaultfd

		/* The memory slot index demand page */
		#define TEST_MEM_SLOT_INDEX 1

		/* Default guest test virtual memory offset */
		#define DEFAULT_GUEST_TEST_MEM 0xc0000000

		#define DEFAULT_GUEST_TEST_MEM_SIZE (1 << 30) /* 1G */

		#ifdef PRINT_PER_PAGE_UPDATES
		@@ -47,75 +41,14 @@
		#define PER_VCPU_DEBUG(...) _no_printf(__VA_ARGS__)
		#endif

		#define MAX_VCPUS 512

		/*
		* Guest/Host shared variables. Ensure addr_gva2hva() and/or
		* sync_global_to/from_guest() are used when accessing from
		* the host. READ/WRITE_ONCE() should also be used with anything
		* that may change.
		*/
		static uint64_t host_page_size;
		static uint64_t guest_page_size;

		static char *guest_data_prototype;

		/*
		* Guest physical memory offset of the testing memory slot.
		* This will be set to the topmost valid physical address minus
		* the test memory size.
		*/
		static uint64_t guest_test_phys_mem;

		/*
		* Guest virtual memory offset of the testing memory slot.
		* Must not conflict with identity mapped test code.
		*/
		static uint64_t guest_test_virt_mem = DEFAULT_GUEST_TEST_MEM;

		struct vcpu_args {
		uint64_t gva;
		uint64_t pages;

		/* Only used by the host userspace part of the vCPU thread */
		int vcpu_id;
		struct kvm_vm *vm;
		};

		static struct vcpu_args vcpu_args[MAX_VCPUS];

		/*
		* Continuously write to the first 8 bytes of each page in the demand paging
		* memory region.
		*/
		static void guest_code(uint32_t vcpu_id)
		{
		uint64_t gva;
		uint64_t pages;
		int i;

		/* Make sure vCPU args data structure is not corrupt. */
		GUEST_ASSERT(vcpu_args[vcpu_id].vcpu_id == vcpu_id);

		gva = vcpu_args[vcpu_id].gva;
		pages = vcpu_args[vcpu_id].pages;

		for (i = 0; i < pages; i++) {
		uint64_t addr = gva + (i * guest_page_size);

		addr &= ~(host_page_size - 1);
		(uint64_t )addr = 0x0123456789ABCDEF;
		}

		GUEST_SYNC(1);
		}

		static void vcpu_worker(void data)
		{
		int ret;
		struct vcpu_args args = (struct vcpu_args )data;
		struct kvm_vm *vm = args->vm;
		int vcpu_id = args->vcpu_id;
		struct vcpu_args vcpu_args = (struct vcpu_args )data;
		int vcpu_id = vcpu_args->vcpu_id;
		struct kvm_vm *vm = perf_test_args.vm;
		struct kvm_run *run;
		struct timespec start, end, ts_diff;

		@@ -141,39 +74,6 @@ static void vcpu_worker(void data)
		return NULL;
		}

		#define PAGE_SHIFT_4K 12
		#define PTES_PER_4K_PT 512

		static struct kvm_vm *create_vm(enum vm_guest_mode mode, int vcpus,
		uint64_t vcpu_memory_bytes)
		{
		struct kvm_vm *vm;
		uint64_t pages = DEFAULT_GUEST_PHY_PAGES;

		/* Account for a few pages per-vCPU for stacks */
		pages += DEFAULT_STACK_PGS * vcpus;

		/*
		* Reserve twice the ammount of memory needed to map the test region and
		* the page table / stacks region, at 4k, for page tables. Do the
		* calculation with 4K page size: the smallest of all archs. (e.g., 64K
		* page size guest will need even less memory for page tables).
		*/
		pages += (2 * pages) / PTES_PER_4K_PT;
		pages += ((2 * vcpus * vcpu_memory_bytes) >> PAGE_SHIFT_4K) /
		PTES_PER_4K_PT;
		pages = vm_adjust_num_guest_pages(mode, pages);

		pr_info("Testing guest mode: %s\n", vm_guest_mode_string(mode));

		vm = _vm_create(mode, pages, O_RDWR);
		kvm_vm_elf_load(vm, program_invocation_name, 0, 0);
		#ifdef __x86_64__
		vm_create_irqchip(vm);
		#endif
		return vm;
		}

		static int handle_uffd_page_request(int uffd, uint64_t addr)
		{
		pid_t tid;
		@@ -186,7 +86,7 @@ static int handle_uffd_page_request(int uffd, uint64_t addr)

		copy.src = (uint64_t)guest_data_prototype;
		copy.dst = addr;
		copy.len = host_page_size;
		copy.len = perf_test_args.host_page_size;
		copy.mode = 0;

		clock_gettime(CLOCK_MONOTONIC, &start);
		@@ -203,7 +103,7 @@ static int handle_uffd_page_request(int uffd, uint64_t addr)
		PER_PAGE_DEBUG("UFFDIO_COPY %d \t%ld ns\n", tid,
		timespec_to_ns(timespec_sub(end, start)));
		PER_PAGE_DEBUG("Paged in %ld bytes at 0x%lx from thread %d\n",
		host_page_size, addr, tid);
		perf_test_args.host_page_size, addr, tid);

		return 0;
		}
		@@ -360,64 +260,21 @@ static void run_test(enum vm_guest_mode mode, bool use_uffd,
		struct timespec start, end, ts_diff;
		int *pipefds = NULL;
		struct kvm_vm *vm;
		uint64_t guest_num_pages;
		int vcpu_id;
		int r;

		vm = create_vm(mode, vcpus, vcpu_memory_bytes);

		guest_page_size = vm_get_page_size(vm);

		TEST_ASSERT(vcpu_memory_bytes % guest_page_size == 0,
		"Guest memory size is not guest page size aligned.");

		guest_num_pages = (vcpus * vcpu_memory_bytes) / guest_page_size;
		guest_num_pages = vm_adjust_num_guest_pages(mode, guest_num_pages);

		/*
		* If there should be more memory in the guest test region than there
		* can be pages in the guest, it will definitely cause problems.
		*/
		TEST_ASSERT(guest_num_pages < vm_get_max_gfn(vm),
		"Requested more guest memory than address space allows.\n"
		" guest pages: %lx max gfn: %x vcpus: %d wss: %lx]\n",
		guest_num_pages, vm_get_max_gfn(vm), vcpus,
		vcpu_memory_bytes);

		host_page_size = getpagesize();
		TEST_ASSERT(vcpu_memory_bytes % host_page_size == 0,
		"Guest memory size is not host page size aligned.");

		guest_test_phys_mem = (vm_get_max_gfn(vm) - guest_num_pages) *
		guest_page_size;
		guest_test_phys_mem &= ~(host_page_size - 1);

		#ifdef __s390x__
		/* Align to 1M (segment size) */
		guest_test_phys_mem &= ~((1 << 20) - 1);
		#endif

		pr_info("guest physical test memory offset: 0x%lx\n", guest_test_phys_mem);

		/* Add an extra memory slot for testing demand paging */
		vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
		guest_test_phys_mem,
		TEST_MEM_SLOT_INDEX,
		guest_num_pages, 0);

		/* Do mapping for the demand paging memory slot */
		virt_map(vm, guest_test_virt_mem, guest_test_phys_mem, guest_num_pages, 0);

		ucall_init(vm, NULL);

		guest_data_prototype = malloc(host_page_size);
		guest_data_prototype = malloc(perf_test_args.host_page_size);
		TEST_ASSERT(guest_data_prototype,
		"Failed to allocate buffer for guest data pattern");
		memset(guest_data_prototype, 0xAB, host_page_size);
		memset(guest_data_prototype, 0xAB, perf_test_args.host_page_size);

		vcpu_threads = malloc(vcpus * sizeof(*vcpu_threads));
		TEST_ASSERT(vcpu_threads, "Memory allocation failed");

		add_vcpus(vm, vcpus, vcpu_memory_bytes);

		if (use_uffd) {
		uffd_handler_threads =
		malloc(vcpus * sizeof(*uffd_handler_threads));
		@@ -428,14 +285,11 @@ static void run_test(enum vm_guest_mode mode, bool use_uffd,

		pipefds = malloc(sizeof(int) * vcpus * 2);
		TEST_ASSERT(pipefds, "Unable to allocate memory for pipefd");
		}

		for (vcpu_id = 0; vcpu_id < vcpus; vcpu_id++) {
		vm_paddr_t vcpu_gpa;
		void *vcpu_hva;

		vm_vcpu_add_default(vm, vcpu_id, guest_code);

		vcpu_gpa = guest_test_phys_mem + (vcpu_id * vcpu_memory_bytes);
		PER_VCPU_DEBUG("Added VCPU %d with test mem gpa [%lx, %lx)\n",
		vcpu_id, vcpu_gpa, vcpu_gpa + vcpu_memory_bytes);
		@@ -443,7 +297,6 @@ static void run_test(enum vm_guest_mode mode, bool use_uffd,
		/* Cache the HVA pointer of the region */
		vcpu_hva = addr_gpa2hva(vm, vcpu_gpa);

		if (use_uffd) {
		/*
		* Set up user fault fd to handle demand paging
		* requests.
		@@ -460,22 +313,10 @@ static void run_test(enum vm_guest_mode mode, bool use_uffd,
		if (r < 0)
		exit(-r);
		}

		#ifdef __x86_64__
		vcpu_set_cpuid(vm, vcpu_id, kvm_get_supported_cpuid());
		#endif

		vcpu_args[vcpu_id].vm = vm;
		vcpu_args[vcpu_id].vcpu_id = vcpu_id;
		vcpu_args[vcpu_id].gva = guest_test_virt_mem +
		(vcpu_id * vcpu_memory_bytes);
		vcpu_args[vcpu_id].pages = vcpu_memory_bytes / guest_page_size;
		}

		/* Export the shared variables to the guest */
		sync_global_to_guest(vm, host_page_size);
		sync_global_to_guest(vm, guest_page_size);
		sync_global_to_guest(vm, vcpu_args);
		sync_global_to_guest(vm, perf_test_args);

		pr_info("Finished creating vCPUs and starting uffd threads\n");

		@@ -483,7 +324,7 @@ static void run_test(enum vm_guest_mode mode, bool use_uffd,

		for (vcpu_id = 0; vcpu_id < vcpus; vcpu_id++) {
		pthread_create(&vcpu_threads[vcpu_id], NULL, vcpu_worker,
		&vcpu_args[vcpu_id]);
		&perf_test_args.vcpu_args[vcpu_id]);
		}

		pr_info("Started all vCPUs\n");
		@@ -514,7 +355,8 @@ static void run_test(enum vm_guest_mode mode, bool use_uffd,
		pr_info("Total guest execution time: %ld.%.9lds\n",
		ts_diff.tv_sec, ts_diff.tv_nsec);
		pr_info("Overall demand paging rate: %f pgs/sec\n",
		guest_num_pages / ((double)ts_diff.tv_sec + (double)ts_diff.tv_nsec / 100000000.0));
		perf_test_args.vcpu_args[0].pages * vcpus /
		((double)ts_diff.tv_sec + (double)ts_diff.tv_nsec / 100000000.0));

		ucall_uninit(vm);
		kvm_vm_free(vm);

tools/testing/selftests/kvm/include/perf_test_util.h

0 → 100644

+187 −0

Original line number	Diff line number	Diff line
		// SPDX-License-Identifier: GPL-2.0
		/*
		* tools/testing/selftests/kvm/include/perf_test_util.h
		*
		* Copyright (C) 2020, Google LLC.
		*/

		#ifndef SELFTEST_KVM_PERF_TEST_UTIL_H
		#define SELFTEST_KVM_PERF_TEST_UTIL_H

		#include "kvm_util.h"
		#include "processor.h"

		#define MAX_VCPUS 512

		#define PAGE_SHIFT_4K 12
		#define PTES_PER_4K_PT 512

		#define TEST_MEM_SLOT_INDEX 1

		/* Default guest test virtual memory offset */
		#define DEFAULT_GUEST_TEST_MEM 0xc0000000

		/*
		* Guest physical memory offset of the testing memory slot.
		* This will be set to the topmost valid physical address minus
		* the test memory size.
		*/
		static uint64_t guest_test_phys_mem;

		/*
		* Guest virtual memory offset of the testing memory slot.
		* Must not conflict with identity mapped test code.
		*/
		static uint64_t guest_test_virt_mem = DEFAULT_GUEST_TEST_MEM;

		struct vcpu_args {
		uint64_t gva;
		uint64_t pages;

		/* Only used by the host userspace part of the vCPU thread */
		int vcpu_id;
		};

		struct perf_test_args {
		struct kvm_vm *vm;
		uint64_t host_page_size;
		uint64_t guest_page_size;

		struct vcpu_args vcpu_args[MAX_VCPUS];
		};

		static struct perf_test_args perf_test_args;

		/*
		* Continuously write to the first 8 bytes of each page in the
		* specified region.
		*/
		static void guest_code(uint32_t vcpu_id)
		{
		struct vcpu_args *vcpu_args = &perf_test_args.vcpu_args[vcpu_id];
		uint64_t gva;
		uint64_t pages;
		int i;

		/* Make sure vCPU args data structure is not corrupt. */
		GUEST_ASSERT(vcpu_args->vcpu_id == vcpu_id);

		gva = vcpu_args->gva;
		pages = vcpu_args->pages;

		for (i = 0; i < pages; i++) {
		uint64_t addr = gva + (i * perf_test_args.guest_page_size);

		addr &= ~(perf_test_args.host_page_size - 1);
		(uint64_t )addr = 0x0123456789ABCDEF;
		}

		GUEST_SYNC(1);
		}

		static struct kvm_vm *create_vm(enum vm_guest_mode mode, int vcpus,
		uint64_t vcpu_memory_bytes)
		{
		struct kvm_vm *vm;
		uint64_t pages = DEFAULT_GUEST_PHY_PAGES;
		uint64_t guest_num_pages;

		/* Account for a few pages per-vCPU for stacks */
		pages += DEFAULT_STACK_PGS * vcpus;

		/*
		* Reserve twice the ammount of memory needed to map the test region and
		* the page table / stacks region, at 4k, for page tables. Do the
		* calculation with 4K page size: the smallest of all archs. (e.g., 64K
		* page size guest will need even less memory for page tables).
		*/
		pages += (2 * pages) / PTES_PER_4K_PT;
		pages += ((2 * vcpus * vcpu_memory_bytes) >> PAGE_SHIFT_4K) /
		PTES_PER_4K_PT;
		pages = vm_adjust_num_guest_pages(mode, pages);

		pr_info("Testing guest mode: %s\n", vm_guest_mode_string(mode));

		vm = _vm_create(mode, pages, O_RDWR);
		kvm_vm_elf_load(vm, program_invocation_name, 0, 0);
		#ifdef __x86_64__
		vm_create_irqchip(vm);
		#endif

		perf_test_args.vm = vm;
		perf_test_args.guest_page_size = vm_get_page_size(vm);
		perf_test_args.host_page_size = getpagesize();

		TEST_ASSERT(vcpu_memory_bytes % perf_test_args.guest_page_size == 0,
		"Guest memory size is not guest page size aligned.");

		guest_num_pages = (vcpus * vcpu_memory_bytes) /
		perf_test_args.guest_page_size;
		guest_num_pages = vm_adjust_num_guest_pages(mode, guest_num_pages);

		/*
		* If there should be more memory in the guest test region than there
		* can be pages in the guest, it will definitely cause problems.
		*/
		TEST_ASSERT(guest_num_pages < vm_get_max_gfn(vm),
		"Requested more guest memory than address space allows.\n"
		" guest pages: %lx max gfn: %x vcpus: %d wss: %lx]\n",
		guest_num_pages, vm_get_max_gfn(vm), vcpus,
		vcpu_memory_bytes);

		TEST_ASSERT(vcpu_memory_bytes % perf_test_args.host_page_size == 0,
		"Guest memory size is not host page size aligned.");

		guest_test_phys_mem = (vm_get_max_gfn(vm) - guest_num_pages) *
		perf_test_args.guest_page_size;
		guest_test_phys_mem &= ~(perf_test_args.host_page_size - 1);

		#ifdef __s390x__
		/* Align to 1M (segment size) */
		guest_test_phys_mem &= ~((1 << 20) - 1);
		#endif

		pr_info("guest physical test memory offset: 0x%lx\n", guest_test_phys_mem);

		/* Add an extra memory slot for testing */
		vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
		guest_test_phys_mem,
		TEST_MEM_SLOT_INDEX,
		guest_num_pages, 0);

		/* Do mapping for the demand paging memory slot */
		virt_map(vm, guest_test_virt_mem, guest_test_phys_mem, guest_num_pages, 0);

		ucall_init(vm, NULL);

		return vm;
		}

		static void add_vcpus(struct kvm_vm *vm, int vcpus, uint64_t vcpu_memory_bytes)
		{
		vm_paddr_t vcpu_gpa;
		struct vcpu_args *vcpu_args;
		int vcpu_id;

		for (vcpu_id = 0; vcpu_id < vcpus; vcpu_id++) {
		vcpu_args = &perf_test_args.vcpu_args[vcpu_id];

		vm_vcpu_add_default(vm, vcpu_id, guest_code);

		#ifdef __x86_64__
		vcpu_set_cpuid(vm, vcpu_id, kvm_get_supported_cpuid());
		#endif

		vcpu_args->vcpu_id = vcpu_id;
		vcpu_args->gva = guest_test_virt_mem +
		(vcpu_id * vcpu_memory_bytes);
		vcpu_args->pages = vcpu_memory_bytes /
		perf_test_args.guest_page_size;

		vcpu_gpa = guest_test_phys_mem + (vcpu_id * vcpu_memory_bytes);
		pr_debug("Added VCPU %d with test mem gpa [%lx, %lx)\n",
		vcpu_id, vcpu_gpa, vcpu_gpa + vcpu_memory_bytes);
		}
		}

		#endif /* SELFTEST_KVM_PERF_TEST_UTIL_H */

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