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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * A memslot-related performance benchmark.
   4 *
   5 * Copyright (C) 2021 Oracle and/or its affiliates.
   6 *
   7 * Basic guest setup / host vCPU thread code lifted from set_memory_region_test.
   8 */
   9#include <pthread.h>
  10#include <sched.h>
  11#include <semaphore.h>
  12#include <stdatomic.h>
  13#include <stdbool.h>
  14#include <stdint.h>
  15#include <stdio.h>
  16#include <stdlib.h>
  17#include <string.h>
  18#include <sys/mman.h>
  19#include <time.h>
  20#include <unistd.h>
  21
  22#include <linux/compiler.h>
  23#include <linux/sizes.h>
  24
  25#include <test_util.h>
  26#include <kvm_util.h>
  27#include <processor.h>
  28
  29#define MEM_EXTRA_SIZE		SZ_64K
  30
  31#define MEM_SIZE		(SZ_512M + MEM_EXTRA_SIZE)
  32#define MEM_GPA			SZ_256M
  33#define MEM_AUX_GPA		MEM_GPA
  34#define MEM_SYNC_GPA		MEM_AUX_GPA
  35#define MEM_TEST_GPA		(MEM_AUX_GPA + MEM_EXTRA_SIZE)
  36#define MEM_TEST_SIZE		(MEM_SIZE - MEM_EXTRA_SIZE)
  37
  38/*
  39 * 32 MiB is max size that gets well over 100 iterations on 509 slots.
  40 * Considering that each slot needs to have at least one page up to
  41 * 8194 slots in use can then be tested (although with slightly
  42 * limited resolution).
  43 */
  44#define MEM_SIZE_MAP		(SZ_32M + MEM_EXTRA_SIZE)
  45#define MEM_TEST_MAP_SIZE	(MEM_SIZE_MAP - MEM_EXTRA_SIZE)
  46
  47/*
  48 * 128 MiB is min size that fills 32k slots with at least one page in each
  49 * while at the same time gets 100+ iterations in such test
  50 *
  51 * 2 MiB chunk size like a typical huge page
  52 */
  53#define MEM_TEST_UNMAP_SIZE		SZ_128M
  54#define MEM_TEST_UNMAP_CHUNK_SIZE	SZ_2M
  55
  56/*
  57 * For the move active test the middle of the test area is placed on
  58 * a memslot boundary: half lies in the memslot being moved, half in
  59 * other memslot(s).
  60 *
  61 * We have different number of memory slots, excluding the reserved
  62 * memory slot 0, on various architectures and configurations. The
  63 * memory size in this test is calculated by picking the maximal
  64 * last memory slot's memory size, with alignment to the largest
  65 * supported page size (64KB). In this way, the selected memory
  66 * size for this test is compatible with test_memslot_move_prepare().
  67 *
  68 * architecture   slots    memory-per-slot    memory-on-last-slot
  69 * --------------------------------------------------------------
  70 * x86-4KB        32763    16KB               160KB
  71 * arm64-4KB      32766    16KB               112KB
  72 * arm64-16KB     32766    16KB               112KB
  73 * arm64-64KB     8192     64KB               128KB
  74 */
  75#define MEM_TEST_MOVE_SIZE		(3 * SZ_64K)
  76#define MEM_TEST_MOVE_GPA_DEST		(MEM_GPA + MEM_SIZE)
  77static_assert(MEM_TEST_MOVE_SIZE <= MEM_TEST_SIZE,
  78	      "invalid move test region size");
  79
  80#define MEM_TEST_VAL_1 0x1122334455667788
  81#define MEM_TEST_VAL_2 0x99AABBCCDDEEFF00
  82
  83struct vm_data {
  84	struct kvm_vm *vm;
  85	struct kvm_vcpu *vcpu;
  86	pthread_t vcpu_thread;
  87	uint32_t nslots;
  88	uint64_t npages;
  89	uint64_t pages_per_slot;
  90	void **hva_slots;
  91	bool mmio_ok;
  92	uint64_t mmio_gpa_min;
  93	uint64_t mmio_gpa_max;
  94};
  95
  96struct sync_area {
  97	uint32_t    guest_page_size;
  98	atomic_bool start_flag;
  99	atomic_bool exit_flag;
 100	atomic_bool sync_flag;
 101	void *move_area_ptr;
 102};
 103
 104/*
 105 * Technically, we need also for the atomic bool to be address-free, which
 106 * is recommended, but not strictly required, by C11 for lockless
 107 * implementations.
 108 * However, in practice both GCC and Clang fulfill this requirement on
 109 * all KVM-supported platforms.
 110 */
 111static_assert(ATOMIC_BOOL_LOCK_FREE == 2, "atomic bool is not lockless");
 112
 113static sem_t vcpu_ready;
 114
 115static bool map_unmap_verify;
 116
 117static bool verbose;
 118#define pr_info_v(...)				\
 119	do {					\
 120		if (verbose)			\
 121			pr_info(__VA_ARGS__);	\
 122	} while (0)
 123
 124static void check_mmio_access(struct vm_data *data, struct kvm_run *run)
 125{
 126	TEST_ASSERT(data->mmio_ok, "Unexpected mmio exit");
 127	TEST_ASSERT(run->mmio.is_write, "Unexpected mmio read");
 128	TEST_ASSERT(run->mmio.len == 8,
 129		    "Unexpected exit mmio size = %u", run->mmio.len);
 130	TEST_ASSERT(run->mmio.phys_addr >= data->mmio_gpa_min &&
 131		    run->mmio.phys_addr <= data->mmio_gpa_max,
 132		    "Unexpected exit mmio address = 0x%llx",
 133		    run->mmio.phys_addr);
 134}
 135
 136static void *vcpu_worker(void *__data)
 137{
 138	struct vm_data *data = __data;
 139	struct kvm_vcpu *vcpu = data->vcpu;
 140	struct kvm_run *run = vcpu->run;
 141	struct ucall uc;
 142
 143	while (1) {
 144		vcpu_run(vcpu);
 145
 146		switch (get_ucall(vcpu, &uc)) {
 147		case UCALL_SYNC:
 148			TEST_ASSERT(uc.args[1] == 0,
 149				"Unexpected sync ucall, got %lx",
 150				(ulong)uc.args[1]);
 151			sem_post(&vcpu_ready);
 152			continue;
 153		case UCALL_NONE:
 154			if (run->exit_reason == KVM_EXIT_MMIO)
 155				check_mmio_access(data, run);
 156			else
 157				goto done;
 158			break;
 159		case UCALL_ABORT:
 160			REPORT_GUEST_ASSERT_1(uc, "val = %lu");
 161			break;
 162		case UCALL_DONE:
 163			goto done;
 164		default:
 165			TEST_FAIL("Unknown ucall %lu", uc.cmd);
 166		}
 167	}
 168
 169done:
 170	return NULL;
 171}
 172
 173static void wait_for_vcpu(void)
 174{
 175	struct timespec ts;
 176
 177	TEST_ASSERT(!clock_gettime(CLOCK_REALTIME, &ts),
 178		    "clock_gettime() failed: %d\n", errno);
 179
 180	ts.tv_sec += 2;
 181	TEST_ASSERT(!sem_timedwait(&vcpu_ready, &ts),
 182		    "sem_timedwait() failed: %d\n", errno);
 183}
 184
 185static void *vm_gpa2hva(struct vm_data *data, uint64_t gpa, uint64_t *rempages)
 186{
 187	uint64_t gpage, pgoffs;
 188	uint32_t slot, slotoffs;
 189	void *base;
 190	uint32_t guest_page_size = data->vm->page_size;
 191
 192	TEST_ASSERT(gpa >= MEM_GPA, "Too low gpa to translate");
 193	TEST_ASSERT(gpa < MEM_GPA + data->npages * guest_page_size,
 194		    "Too high gpa to translate");
 195	gpa -= MEM_GPA;
 196
 197	gpage = gpa / guest_page_size;
 198	pgoffs = gpa % guest_page_size;
 199	slot = min(gpage / data->pages_per_slot, (uint64_t)data->nslots - 1);
 200	slotoffs = gpage - (slot * data->pages_per_slot);
 201
 202	if (rempages) {
 203		uint64_t slotpages;
 204
 205		if (slot == data->nslots - 1)
 206			slotpages = data->npages - slot * data->pages_per_slot;
 207		else
 208			slotpages = data->pages_per_slot;
 209
 210		TEST_ASSERT(!pgoffs,
 211			    "Asking for remaining pages in slot but gpa not page aligned");
 212		*rempages = slotpages - slotoffs;
 213	}
 214
 215	base = data->hva_slots[slot];
 216	return (uint8_t *)base + slotoffs * guest_page_size + pgoffs;
 217}
 218
 219static uint64_t vm_slot2gpa(struct vm_data *data, uint32_t slot)
 220{
 221	uint32_t guest_page_size = data->vm->page_size;
 222
 223	TEST_ASSERT(slot < data->nslots, "Too high slot number");
 224
 225	return MEM_GPA + slot * data->pages_per_slot * guest_page_size;
 226}
 227
 228static struct vm_data *alloc_vm(void)
 229{
 230	struct vm_data *data;
 231
 232	data = malloc(sizeof(*data));
 233	TEST_ASSERT(data, "malloc(vmdata) failed");
 234
 235	data->vm = NULL;
 236	data->vcpu = NULL;
 237	data->hva_slots = NULL;
 238
 239	return data;
 240}
 241
 242static bool check_slot_pages(uint32_t host_page_size, uint32_t guest_page_size,
 243			     uint64_t pages_per_slot, uint64_t rempages)
 244{
 245	if (!pages_per_slot)
 246		return false;
 247
 248	if ((pages_per_slot * guest_page_size) % host_page_size)
 249		return false;
 250
 251	if ((rempages * guest_page_size) % host_page_size)
 252		return false;
 253
 254	return true;
 255}
 256
 257
 258static uint64_t get_max_slots(struct vm_data *data, uint32_t host_page_size)
 259{
 260	uint32_t guest_page_size = data->vm->page_size;
 261	uint64_t mempages, pages_per_slot, rempages;
 262	uint64_t slots;
 263
 264	mempages = data->npages;
 265	slots = data->nslots;
 266	while (--slots > 1) {
 267		pages_per_slot = mempages / slots;
 268		if (!pages_per_slot)
 269			continue;
 270
 271		rempages = mempages % pages_per_slot;
 272		if (check_slot_pages(host_page_size, guest_page_size,
 273				     pages_per_slot, rempages))
 274			return slots + 1;	/* slot 0 is reserved */
 275	}
 276
 277	return 0;
 278}
 279
 280static bool prepare_vm(struct vm_data *data, int nslots, uint64_t *maxslots,
 281		       void *guest_code, uint64_t mem_size,
 282		       struct timespec *slot_runtime)
 283{
 284	uint64_t mempages, rempages;
 285	uint64_t guest_addr;
 286	uint32_t slot, host_page_size, guest_page_size;
 287	struct timespec tstart;
 288	struct sync_area *sync;
 289
 290	host_page_size = getpagesize();
 291	guest_page_size = vm_guest_mode_params[VM_MODE_DEFAULT].page_size;
 292	mempages = mem_size / guest_page_size;
 293
 294	data->vm = __vm_create_with_one_vcpu(&data->vcpu, mempages, guest_code);
 295	TEST_ASSERT(data->vm->page_size == guest_page_size, "Invalid VM page size");
 296
 297	data->npages = mempages;
 298	TEST_ASSERT(data->npages > 1, "Can't test without any memory");
 299	data->nslots = nslots;
 300	data->pages_per_slot = data->npages / data->nslots;
 301	rempages = data->npages % data->nslots;
 302	if (!check_slot_pages(host_page_size, guest_page_size,
 303			      data->pages_per_slot, rempages)) {
 304		*maxslots = get_max_slots(data, host_page_size);
 305		return false;
 306	}
 307
 308	data->hva_slots = malloc(sizeof(*data->hva_slots) * data->nslots);
 309	TEST_ASSERT(data->hva_slots, "malloc() fail");
 310
 311	data->vm = __vm_create_with_one_vcpu(&data->vcpu, mempages, guest_code);
 312
 313	pr_info_v("Adding slots 1..%i, each slot with %"PRIu64" pages + %"PRIu64" extra pages last\n",
 314		data->nslots, data->pages_per_slot, rempages);
 315
 316	clock_gettime(CLOCK_MONOTONIC, &tstart);
 317	for (slot = 1, guest_addr = MEM_GPA; slot <= data->nslots; slot++) {
 318		uint64_t npages;
 319
 320		npages = data->pages_per_slot;
 321		if (slot == data->nslots)
 322			npages += rempages;
 323
 324		vm_userspace_mem_region_add(data->vm, VM_MEM_SRC_ANONYMOUS,
 325					    guest_addr, slot, npages,
 326					    0);
 327		guest_addr += npages * guest_page_size;
 328	}
 329	*slot_runtime = timespec_elapsed(tstart);
 330
 331	for (slot = 1, guest_addr = MEM_GPA; slot <= data->nslots; slot++) {
 332		uint64_t npages;
 333		uint64_t gpa;
 334
 335		npages = data->pages_per_slot;
 336		if (slot == data->nslots)
 337			npages += rempages;
 338
 339		gpa = vm_phy_pages_alloc(data->vm, npages, guest_addr, slot);
 340		TEST_ASSERT(gpa == guest_addr,
 341			    "vm_phy_pages_alloc() failed\n");
 342
 343		data->hva_slots[slot - 1] = addr_gpa2hva(data->vm, guest_addr);
 344		memset(data->hva_slots[slot - 1], 0, npages * guest_page_size);
 345
 346		guest_addr += npages * guest_page_size;
 347	}
 348
 349	virt_map(data->vm, MEM_GPA, MEM_GPA, data->npages);
 350
 351	sync = (typeof(sync))vm_gpa2hva(data, MEM_SYNC_GPA, NULL);
 352	atomic_init(&sync->start_flag, false);
 353	atomic_init(&sync->exit_flag, false);
 354	atomic_init(&sync->sync_flag, false);
 355
 356	data->mmio_ok = false;
 357
 358	return true;
 359}
 360
 361static void launch_vm(struct vm_data *data)
 362{
 363	pr_info_v("Launching the test VM\n");
 364
 365	pthread_create(&data->vcpu_thread, NULL, vcpu_worker, data);
 366
 367	/* Ensure the guest thread is spun up. */
 368	wait_for_vcpu();
 369}
 370
 371static void free_vm(struct vm_data *data)
 372{
 373	kvm_vm_free(data->vm);
 374	free(data->hva_slots);
 375	free(data);
 376}
 377
 378static void wait_guest_exit(struct vm_data *data)
 379{
 380	pthread_join(data->vcpu_thread, NULL);
 381}
 382
 383static void let_guest_run(struct sync_area *sync)
 384{
 385	atomic_store_explicit(&sync->start_flag, true, memory_order_release);
 386}
 387
 388static void guest_spin_until_start(void)
 389{
 390	struct sync_area *sync = (typeof(sync))MEM_SYNC_GPA;
 391
 392	while (!atomic_load_explicit(&sync->start_flag, memory_order_acquire))
 393		;
 394}
 395
 396static void make_guest_exit(struct sync_area *sync)
 397{
 398	atomic_store_explicit(&sync->exit_flag, true, memory_order_release);
 399}
 400
 401static bool _guest_should_exit(void)
 402{
 403	struct sync_area *sync = (typeof(sync))MEM_SYNC_GPA;
 404
 405	return atomic_load_explicit(&sync->exit_flag, memory_order_acquire);
 406}
 407
 408#define guest_should_exit() unlikely(_guest_should_exit())
 409
 410/*
 411 * noinline so we can easily see how much time the host spends waiting
 412 * for the guest.
 413 * For the same reason use alarm() instead of polling clock_gettime()
 414 * to implement a wait timeout.
 415 */
 416static noinline void host_perform_sync(struct sync_area *sync)
 417{
 418	alarm(2);
 419
 420	atomic_store_explicit(&sync->sync_flag, true, memory_order_release);
 421	while (atomic_load_explicit(&sync->sync_flag, memory_order_acquire))
 422		;
 423
 424	alarm(0);
 425}
 426
 427static bool guest_perform_sync(void)
 428{
 429	struct sync_area *sync = (typeof(sync))MEM_SYNC_GPA;
 430	bool expected;
 431
 432	do {
 433		if (guest_should_exit())
 434			return false;
 435
 436		expected = true;
 437	} while (!atomic_compare_exchange_weak_explicit(&sync->sync_flag,
 438							&expected, false,
 439							memory_order_acq_rel,
 440							memory_order_relaxed));
 441
 442	return true;
 443}
 444
 445static void guest_code_test_memslot_move(void)
 446{
 447	struct sync_area *sync = (typeof(sync))MEM_SYNC_GPA;
 448	uint32_t page_size = (typeof(page_size))READ_ONCE(sync->guest_page_size);
 449	uintptr_t base = (typeof(base))READ_ONCE(sync->move_area_ptr);
 450
 451	GUEST_SYNC(0);
 452
 453	guest_spin_until_start();
 454
 455	while (!guest_should_exit()) {
 456		uintptr_t ptr;
 457
 458		for (ptr = base; ptr < base + MEM_TEST_MOVE_SIZE;
 459		     ptr += page_size)
 460			*(uint64_t *)ptr = MEM_TEST_VAL_1;
 461
 462		/*
 463		 * No host sync here since the MMIO exits are so expensive
 464		 * that the host would spend most of its time waiting for
 465		 * the guest and so instead of measuring memslot move
 466		 * performance we would measure the performance and
 467		 * likelihood of MMIO exits
 468		 */
 469	}
 470
 471	GUEST_DONE();
 472}
 473
 474static void guest_code_test_memslot_map(void)
 475{
 476	struct sync_area *sync = (typeof(sync))MEM_SYNC_GPA;
 477	uint32_t page_size = (typeof(page_size))READ_ONCE(sync->guest_page_size);
 478
 479	GUEST_SYNC(0);
 480
 481	guest_spin_until_start();
 482
 483	while (1) {
 484		uintptr_t ptr;
 485
 486		for (ptr = MEM_TEST_GPA;
 487		     ptr < MEM_TEST_GPA + MEM_TEST_MAP_SIZE / 2;
 488		     ptr += page_size)
 489			*(uint64_t *)ptr = MEM_TEST_VAL_1;
 490
 491		if (!guest_perform_sync())
 492			break;
 493
 494		for (ptr = MEM_TEST_GPA + MEM_TEST_MAP_SIZE / 2;
 495		     ptr < MEM_TEST_GPA + MEM_TEST_MAP_SIZE;
 496		     ptr += page_size)
 497			*(uint64_t *)ptr = MEM_TEST_VAL_2;
 498
 499		if (!guest_perform_sync())
 500			break;
 501	}
 502
 503	GUEST_DONE();
 504}
 505
 506static void guest_code_test_memslot_unmap(void)
 507{
 508	struct sync_area *sync = (typeof(sync))MEM_SYNC_GPA;
 509
 510	GUEST_SYNC(0);
 511
 512	guest_spin_until_start();
 513
 514	while (1) {
 515		uintptr_t ptr = MEM_TEST_GPA;
 516
 517		/*
 518		 * We can afford to access (map) just a small number of pages
 519		 * per host sync as otherwise the host will spend
 520		 * a significant amount of its time waiting for the guest
 521		 * (instead of doing unmap operations), so this will
 522		 * effectively turn this test into a map performance test.
 523		 *
 524		 * Just access a single page to be on the safe side.
 525		 */
 526		*(uint64_t *)ptr = MEM_TEST_VAL_1;
 527
 528		if (!guest_perform_sync())
 529			break;
 530
 531		ptr += MEM_TEST_UNMAP_SIZE / 2;
 532		*(uint64_t *)ptr = MEM_TEST_VAL_2;
 533
 534		if (!guest_perform_sync())
 535			break;
 536	}
 537
 538	GUEST_DONE();
 539}
 540
 541static void guest_code_test_memslot_rw(void)
 542{
 543	struct sync_area *sync = (typeof(sync))MEM_SYNC_GPA;
 544	uint32_t page_size = (typeof(page_size))READ_ONCE(sync->guest_page_size);
 545
 546	GUEST_SYNC(0);
 547
 548	guest_spin_until_start();
 549
 550	while (1) {
 551		uintptr_t ptr;
 552
 553		for (ptr = MEM_TEST_GPA;
 554		     ptr < MEM_TEST_GPA + MEM_TEST_SIZE; ptr += page_size)
 555			*(uint64_t *)ptr = MEM_TEST_VAL_1;
 556
 557		if (!guest_perform_sync())
 558			break;
 559
 560		for (ptr = MEM_TEST_GPA + page_size / 2;
 561		     ptr < MEM_TEST_GPA + MEM_TEST_SIZE; ptr += page_size) {
 562			uint64_t val = *(uint64_t *)ptr;
 563
 564			GUEST_ASSERT_1(val == MEM_TEST_VAL_2, val);
 565			*(uint64_t *)ptr = 0;
 566		}
 567
 568		if (!guest_perform_sync())
 569			break;
 570	}
 571
 572	GUEST_DONE();
 573}
 574
 575static bool test_memslot_move_prepare(struct vm_data *data,
 576				      struct sync_area *sync,
 577				      uint64_t *maxslots, bool isactive)
 578{
 579	uint32_t guest_page_size = data->vm->page_size;
 580	uint64_t movesrcgpa, movetestgpa;
 581
 582	movesrcgpa = vm_slot2gpa(data, data->nslots - 1);
 583
 584	if (isactive) {
 585		uint64_t lastpages;
 586
 587		vm_gpa2hva(data, movesrcgpa, &lastpages);
 588		if (lastpages * guest_page_size < MEM_TEST_MOVE_SIZE / 2) {
 589			*maxslots = 0;
 590			return false;
 591		}
 592	}
 593
 594	movetestgpa = movesrcgpa - (MEM_TEST_MOVE_SIZE / (isactive ? 2 : 1));
 595	sync->move_area_ptr = (void *)movetestgpa;
 596
 597	if (isactive) {
 598		data->mmio_ok = true;
 599		data->mmio_gpa_min = movesrcgpa;
 600		data->mmio_gpa_max = movesrcgpa + MEM_TEST_MOVE_SIZE / 2 - 1;
 601	}
 602
 603	return true;
 604}
 605
 606static bool test_memslot_move_prepare_active(struct vm_data *data,
 607					     struct sync_area *sync,
 608					     uint64_t *maxslots)
 609{
 610	return test_memslot_move_prepare(data, sync, maxslots, true);
 611}
 612
 613static bool test_memslot_move_prepare_inactive(struct vm_data *data,
 614					       struct sync_area *sync,
 615					       uint64_t *maxslots)
 616{
 617	return test_memslot_move_prepare(data, sync, maxslots, false);
 618}
 619
 620static void test_memslot_move_loop(struct vm_data *data, struct sync_area *sync)
 621{
 622	uint64_t movesrcgpa;
 623
 624	movesrcgpa = vm_slot2gpa(data, data->nslots - 1);
 625	vm_mem_region_move(data->vm, data->nslots - 1 + 1,
 626			   MEM_TEST_MOVE_GPA_DEST);
 627	vm_mem_region_move(data->vm, data->nslots - 1 + 1, movesrcgpa);
 628}
 629
 630static void test_memslot_do_unmap(struct vm_data *data,
 631				  uint64_t offsp, uint64_t count)
 632{
 633	uint64_t gpa, ctr;
 634	uint32_t guest_page_size = data->vm->page_size;
 635
 636	for (gpa = MEM_TEST_GPA + offsp * guest_page_size, ctr = 0; ctr < count; ) {
 637		uint64_t npages;
 638		void *hva;
 639		int ret;
 640
 641		hva = vm_gpa2hva(data, gpa, &npages);
 642		TEST_ASSERT(npages, "Empty memory slot at gptr 0x%"PRIx64, gpa);
 643		npages = min(npages, count - ctr);
 644		ret = madvise(hva, npages * guest_page_size, MADV_DONTNEED);
 645		TEST_ASSERT(!ret,
 646			    "madvise(%p, MADV_DONTNEED) on VM memory should not fail for gptr 0x%"PRIx64,
 647			    hva, gpa);
 648		ctr += npages;
 649		gpa += npages * guest_page_size;
 650	}
 651	TEST_ASSERT(ctr == count,
 652		    "madvise(MADV_DONTNEED) should exactly cover all of the requested area");
 653}
 654
 655static void test_memslot_map_unmap_check(struct vm_data *data,
 656					 uint64_t offsp, uint64_t valexp)
 657{
 658	uint64_t gpa;
 659	uint64_t *val;
 660	uint32_t guest_page_size = data->vm->page_size;
 661
 662	if (!map_unmap_verify)
 663		return;
 664
 665	gpa = MEM_TEST_GPA + offsp * guest_page_size;
 666	val = (typeof(val))vm_gpa2hva(data, gpa, NULL);
 667	TEST_ASSERT(*val == valexp,
 668		    "Guest written values should read back correctly before unmap (%"PRIu64" vs %"PRIu64" @ %"PRIx64")",
 669		    *val, valexp, gpa);
 670	*val = 0;
 671}
 672
 673static void test_memslot_map_loop(struct vm_data *data, struct sync_area *sync)
 674{
 675	uint32_t guest_page_size = data->vm->page_size;
 676	uint64_t guest_pages = MEM_TEST_MAP_SIZE / guest_page_size;
 677
 678	/*
 679	 * Unmap the second half of the test area while guest writes to (maps)
 680	 * the first half.
 681	 */
 682	test_memslot_do_unmap(data, guest_pages / 2, guest_pages / 2);
 683
 684	/*
 685	 * Wait for the guest to finish writing the first half of the test
 686	 * area, verify the written value on the first and the last page of
 687	 * this area and then unmap it.
 688	 * Meanwhile, the guest is writing to (mapping) the second half of
 689	 * the test area.
 690	 */
 691	host_perform_sync(sync);
 692	test_memslot_map_unmap_check(data, 0, MEM_TEST_VAL_1);
 693	test_memslot_map_unmap_check(data, guest_pages / 2 - 1, MEM_TEST_VAL_1);
 694	test_memslot_do_unmap(data, 0, guest_pages / 2);
 695
 696
 697	/*
 698	 * Wait for the guest to finish writing the second half of the test
 699	 * area and verify the written value on the first and the last page
 700	 * of this area.
 701	 * The area will be unmapped at the beginning of the next loop
 702	 * iteration.
 703	 * Meanwhile, the guest is writing to (mapping) the first half of
 704	 * the test area.
 705	 */
 706	host_perform_sync(sync);
 707	test_memslot_map_unmap_check(data, guest_pages / 2, MEM_TEST_VAL_2);
 708	test_memslot_map_unmap_check(data, guest_pages - 1, MEM_TEST_VAL_2);
 709}
 710
 711static void test_memslot_unmap_loop_common(struct vm_data *data,
 712					   struct sync_area *sync,
 713					   uint64_t chunk)
 714{
 715	uint32_t guest_page_size = data->vm->page_size;
 716	uint64_t guest_pages = MEM_TEST_UNMAP_SIZE / guest_page_size;
 717	uint64_t ctr;
 718
 719	/*
 720	 * Wait for the guest to finish mapping page(s) in the first half
 721	 * of the test area, verify the written value and then perform unmap
 722	 * of this area.
 723	 * Meanwhile, the guest is writing to (mapping) page(s) in the second
 724	 * half of the test area.
 725	 */
 726	host_perform_sync(sync);
 727	test_memslot_map_unmap_check(data, 0, MEM_TEST_VAL_1);
 728	for (ctr = 0; ctr < guest_pages / 2; ctr += chunk)
 729		test_memslot_do_unmap(data, ctr, chunk);
 730
 731	/* Likewise, but for the opposite host / guest areas */
 732	host_perform_sync(sync);
 733	test_memslot_map_unmap_check(data, guest_pages / 2, MEM_TEST_VAL_2);
 734	for (ctr = guest_pages / 2; ctr < guest_pages; ctr += chunk)
 735		test_memslot_do_unmap(data, ctr, chunk);
 736}
 737
 738static void test_memslot_unmap_loop(struct vm_data *data,
 739				    struct sync_area *sync)
 740{
 741	uint32_t host_page_size = getpagesize();
 742	uint32_t guest_page_size = data->vm->page_size;
 743	uint64_t guest_chunk_pages = guest_page_size >= host_page_size ?
 744					1 : host_page_size / guest_page_size;
 745
 746	test_memslot_unmap_loop_common(data, sync, guest_chunk_pages);
 747}
 748
 749static void test_memslot_unmap_loop_chunked(struct vm_data *data,
 750					    struct sync_area *sync)
 751{
 752	uint32_t guest_page_size = data->vm->page_size;
 753	uint64_t guest_chunk_pages = MEM_TEST_UNMAP_CHUNK_SIZE / guest_page_size;
 754
 755	test_memslot_unmap_loop_common(data, sync, guest_chunk_pages);
 756}
 757
 758static void test_memslot_rw_loop(struct vm_data *data, struct sync_area *sync)
 759{
 760	uint64_t gptr;
 761	uint32_t guest_page_size = data->vm->page_size;
 762
 763	for (gptr = MEM_TEST_GPA + guest_page_size / 2;
 764	     gptr < MEM_TEST_GPA + MEM_TEST_SIZE; gptr += guest_page_size)
 765		*(uint64_t *)vm_gpa2hva(data, gptr, NULL) = MEM_TEST_VAL_2;
 766
 767	host_perform_sync(sync);
 768
 769	for (gptr = MEM_TEST_GPA;
 770	     gptr < MEM_TEST_GPA + MEM_TEST_SIZE; gptr += guest_page_size) {
 771		uint64_t *vptr = (typeof(vptr))vm_gpa2hva(data, gptr, NULL);
 772		uint64_t val = *vptr;
 773
 774		TEST_ASSERT(val == MEM_TEST_VAL_1,
 775			    "Guest written values should read back correctly (is %"PRIu64" @ %"PRIx64")",
 776			    val, gptr);
 777		*vptr = 0;
 778	}
 779
 780	host_perform_sync(sync);
 781}
 782
 783struct test_data {
 784	const char *name;
 785	uint64_t mem_size;
 786	void (*guest_code)(void);
 787	bool (*prepare)(struct vm_data *data, struct sync_area *sync,
 788			uint64_t *maxslots);
 789	void (*loop)(struct vm_data *data, struct sync_area *sync);
 790};
 791
 792static bool test_execute(int nslots, uint64_t *maxslots,
 793			 unsigned int maxtime,
 794			 const struct test_data *tdata,
 795			 uint64_t *nloops,
 796			 struct timespec *slot_runtime,
 797			 struct timespec *guest_runtime)
 798{
 799	uint64_t mem_size = tdata->mem_size ? : MEM_SIZE;
 800	struct vm_data *data;
 801	struct sync_area *sync;
 802	struct timespec tstart;
 803	bool ret = true;
 804
 805	data = alloc_vm();
 806	if (!prepare_vm(data, nslots, maxslots, tdata->guest_code,
 807			mem_size, slot_runtime)) {
 808		ret = false;
 809		goto exit_free;
 810	}
 811
 812	sync = (typeof(sync))vm_gpa2hva(data, MEM_SYNC_GPA, NULL);
 813
 814	sync->guest_page_size = data->vm->page_size;
 815	if (tdata->prepare &&
 816	    !tdata->prepare(data, sync, maxslots)) {
 817		ret = false;
 818		goto exit_free;
 819	}
 820
 821	launch_vm(data);
 822
 823	clock_gettime(CLOCK_MONOTONIC, &tstart);
 824	let_guest_run(sync);
 825
 826	while (1) {
 827		*guest_runtime = timespec_elapsed(tstart);
 828		if (guest_runtime->tv_sec >= maxtime)
 829			break;
 830
 831		tdata->loop(data, sync);
 832
 833		(*nloops)++;
 834	}
 835
 836	make_guest_exit(sync);
 837	wait_guest_exit(data);
 838
 839exit_free:
 840	free_vm(data);
 841
 842	return ret;
 843}
 844
 845static const struct test_data tests[] = {
 846	{
 847		.name = "map",
 848		.mem_size = MEM_SIZE_MAP,
 849		.guest_code = guest_code_test_memslot_map,
 850		.loop = test_memslot_map_loop,
 851	},
 852	{
 853		.name = "unmap",
 854		.mem_size = MEM_TEST_UNMAP_SIZE + MEM_EXTRA_SIZE,
 855		.guest_code = guest_code_test_memslot_unmap,
 856		.loop = test_memslot_unmap_loop,
 857	},
 858	{
 859		.name = "unmap chunked",
 860		.mem_size = MEM_TEST_UNMAP_SIZE + MEM_EXTRA_SIZE,
 861		.guest_code = guest_code_test_memslot_unmap,
 862		.loop = test_memslot_unmap_loop_chunked,
 863	},
 864	{
 865		.name = "move active area",
 866		.guest_code = guest_code_test_memslot_move,
 867		.prepare = test_memslot_move_prepare_active,
 868		.loop = test_memslot_move_loop,
 869	},
 870	{
 871		.name = "move inactive area",
 872		.guest_code = guest_code_test_memslot_move,
 873		.prepare = test_memslot_move_prepare_inactive,
 874		.loop = test_memslot_move_loop,
 875	},
 876	{
 877		.name = "RW",
 878		.guest_code = guest_code_test_memslot_rw,
 879		.loop = test_memslot_rw_loop
 880	},
 881};
 882
 883#define NTESTS ARRAY_SIZE(tests)
 884
 885struct test_args {
 886	int tfirst;
 887	int tlast;
 888	int nslots;
 889	int seconds;
 890	int runs;
 891};
 892
 893static void help(char *name, struct test_args *targs)
 894{
 895	int ctr;
 896
 897	pr_info("usage: %s [-h] [-v] [-d] [-s slots] [-f first_test] [-e last_test] [-l test_length] [-r run_count]\n",
 898		name);
 899	pr_info(" -h: print this help screen.\n");
 900	pr_info(" -v: enable verbose mode (not for benchmarking).\n");
 901	pr_info(" -d: enable extra debug checks.\n");
 902	pr_info(" -s: specify memslot count cap (-1 means no cap; currently: %i)\n",
 903		targs->nslots);
 904	pr_info(" -f: specify the first test to run (currently: %i; max %zu)\n",
 905		targs->tfirst, NTESTS - 1);
 906	pr_info(" -e: specify the last test to run (currently: %i; max %zu)\n",
 907		targs->tlast, NTESTS - 1);
 908	pr_info(" -l: specify the test length in seconds (currently: %i)\n",
 909		targs->seconds);
 910	pr_info(" -r: specify the number of runs per test (currently: %i)\n",
 911		targs->runs);
 912
 913	pr_info("\nAvailable tests:\n");
 914	for (ctr = 0; ctr < NTESTS; ctr++)
 915		pr_info("%d: %s\n", ctr, tests[ctr].name);
 916}
 917
 918static bool check_memory_sizes(void)
 919{
 920	uint32_t host_page_size = getpagesize();
 921	uint32_t guest_page_size = vm_guest_mode_params[VM_MODE_DEFAULT].page_size;
 922
 923	if (host_page_size > SZ_64K || guest_page_size > SZ_64K) {
 924		pr_info("Unsupported page size on host (0x%x) or guest (0x%x)\n",
 925			host_page_size, guest_page_size);
 926		return false;
 927	}
 928
 929	if (MEM_SIZE % guest_page_size ||
 930	    MEM_TEST_SIZE % guest_page_size) {
 931		pr_info("invalid MEM_SIZE or MEM_TEST_SIZE\n");
 932		return false;
 933	}
 934
 935	if (MEM_SIZE_MAP % guest_page_size		||
 936	    MEM_TEST_MAP_SIZE % guest_page_size		||
 937	    (MEM_TEST_MAP_SIZE / guest_page_size) <= 2	||
 938	    (MEM_TEST_MAP_SIZE / guest_page_size) % 2) {
 939		pr_info("invalid MEM_SIZE_MAP or MEM_TEST_MAP_SIZE\n");
 940		return false;
 941	}
 942
 943	if (MEM_TEST_UNMAP_SIZE > MEM_TEST_SIZE		||
 944	    MEM_TEST_UNMAP_SIZE % guest_page_size	||
 945	    (MEM_TEST_UNMAP_SIZE / guest_page_size) %
 946	    (2 * MEM_TEST_UNMAP_CHUNK_SIZE / guest_page_size)) {
 947		pr_info("invalid MEM_TEST_UNMAP_SIZE or MEM_TEST_UNMAP_CHUNK_SIZE\n");
 948		return false;
 949	}
 950
 951	return true;
 952}
 953
 954static bool parse_args(int argc, char *argv[],
 955		       struct test_args *targs)
 956{
 957	uint32_t max_mem_slots;
 958	int opt;
 959
 960	while ((opt = getopt(argc, argv, "hvds:f:e:l:r:")) != -1) {
 961		switch (opt) {
 962		case 'h':
 963		default:
 964			help(argv[0], targs);
 965			return false;
 966		case 'v':
 967			verbose = true;
 968			break;
 969		case 'd':
 970			map_unmap_verify = true;
 971			break;
 972		case 's':
 973			targs->nslots = atoi_paranoid(optarg);
 974			if (targs->nslots <= 1 && targs->nslots != -1) {
 975				pr_info("Slot count cap must be larger than 1 or -1 for no cap\n");
 976				return false;
 977			}
 978			break;
 979		case 'f':
 980			targs->tfirst = atoi_non_negative("First test", optarg);
 981			break;
 982		case 'e':
 983			targs->tlast = atoi_non_negative("Last test", optarg);
 984			if (targs->tlast >= NTESTS) {
 985				pr_info("Last test to run has to be non-negative and less than %zu\n",
 986					NTESTS);
 987				return false;
 988			}
 989			break;
 990		case 'l':
 991			targs->seconds = atoi_non_negative("Test length", optarg);
 992			break;
 993		case 'r':
 994			targs->runs = atoi_positive("Runs per test", optarg);
 995			break;
 996		}
 997	}
 998
 999	if (optind < argc) {
1000		help(argv[0], targs);
1001		return false;
1002	}
1003
1004	if (targs->tfirst > targs->tlast) {
1005		pr_info("First test to run cannot be greater than the last test to run\n");
1006		return false;
1007	}
1008
1009	max_mem_slots = kvm_check_cap(KVM_CAP_NR_MEMSLOTS);
1010	if (max_mem_slots <= 1) {
1011		pr_info("KVM_CAP_NR_MEMSLOTS should be greater than 1\n");
1012		return false;
1013	}
1014
1015	/* Memory slot 0 is reserved */
1016	if (targs->nslots == -1)
1017		targs->nslots = max_mem_slots - 1;
1018	else
1019		targs->nslots = min_t(int, targs->nslots, max_mem_slots) - 1;
1020
1021	pr_info_v("Allowed Number of memory slots: %"PRIu32"\n",
1022		  targs->nslots + 1);
1023
1024	return true;
1025}
1026
1027struct test_result {
1028	struct timespec slot_runtime, guest_runtime, iter_runtime;
1029	int64_t slottimens, runtimens;
1030	uint64_t nloops;
1031};
1032
1033static bool test_loop(const struct test_data *data,
1034		      const struct test_args *targs,
1035		      struct test_result *rbestslottime,
1036		      struct test_result *rbestruntime)
1037{
1038	uint64_t maxslots;
1039	struct test_result result;
1040
1041	result.nloops = 0;
1042	if (!test_execute(targs->nslots, &maxslots, targs->seconds, data,
1043			  &result.nloops,
1044			  &result.slot_runtime, &result.guest_runtime)) {
1045		if (maxslots)
1046			pr_info("Memslot count too high for this test, decrease the cap (max is %"PRIu64")\n",
1047				maxslots);
1048		else
1049			pr_info("Memslot count may be too high for this test, try adjusting the cap\n");
1050
1051		return false;
1052	}
1053
1054	pr_info("Test took %ld.%.9lds for slot setup + %ld.%.9lds all iterations\n",
1055		result.slot_runtime.tv_sec, result.slot_runtime.tv_nsec,
1056		result.guest_runtime.tv_sec, result.guest_runtime.tv_nsec);
1057	if (!result.nloops) {
1058		pr_info("No full loops done - too short test time or system too loaded?\n");
1059		return true;
1060	}
1061
1062	result.iter_runtime = timespec_div(result.guest_runtime,
1063					   result.nloops);
1064	pr_info("Done %"PRIu64" iterations, avg %ld.%.9lds each\n",
1065		result.nloops,
1066		result.iter_runtime.tv_sec,
1067		result.iter_runtime.tv_nsec);
1068	result.slottimens = timespec_to_ns(result.slot_runtime);
1069	result.runtimens = timespec_to_ns(result.iter_runtime);
1070
1071	/*
1072	 * Only rank the slot setup time for tests using the whole test memory
1073	 * area so they are comparable
1074	 */
1075	if (!data->mem_size &&
1076	    (!rbestslottime->slottimens ||
1077	     result.slottimens < rbestslottime->slottimens))
1078		*rbestslottime = result;
1079	if (!rbestruntime->runtimens ||
1080	    result.runtimens < rbestruntime->runtimens)
1081		*rbestruntime = result;
1082
1083	return true;
1084}
1085
1086int main(int argc, char *argv[])
1087{
1088	struct test_args targs = {
1089		.tfirst = 0,
1090		.tlast = NTESTS - 1,
1091		.nslots = -1,
1092		.seconds = 5,
1093		.runs = 1,
1094	};
1095	struct test_result rbestslottime;
1096	int tctr;
1097
1098	if (!check_memory_sizes())
1099		return -1;
1100
1101	if (!parse_args(argc, argv, &targs))
1102		return -1;
1103
1104	rbestslottime.slottimens = 0;
1105	for (tctr = targs.tfirst; tctr <= targs.tlast; tctr++) {
1106		const struct test_data *data = &tests[tctr];
1107		unsigned int runctr;
1108		struct test_result rbestruntime;
1109
1110		if (tctr > targs.tfirst)
1111			pr_info("\n");
1112
1113		pr_info("Testing %s performance with %i runs, %d seconds each\n",
1114			data->name, targs.runs, targs.seconds);
1115
1116		rbestruntime.runtimens = 0;
1117		for (runctr = 0; runctr < targs.runs; runctr++)
1118			if (!test_loop(data, &targs,
1119				       &rbestslottime, &rbestruntime))
1120				break;
1121
1122		if (rbestruntime.runtimens)
1123			pr_info("Best runtime result was %ld.%.9lds per iteration (with %"PRIu64" iterations)\n",
1124				rbestruntime.iter_runtime.tv_sec,
1125				rbestruntime.iter_runtime.tv_nsec,
1126				rbestruntime.nloops);
1127	}
1128
1129	if (rbestslottime.slottimens)
1130		pr_info("Best slot setup time for the whole test area was %ld.%.9lds\n",
1131			rbestslottime.slot_runtime.tv_sec,
1132			rbestslottime.slot_runtime.tv_nsec);
1133
1134	return 0;
1135}