Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1553 insertions, 0 deletions

diff --git a/tools/testing/selftests/mm/khugepaged.c b/tools/testing/selftests/mm/khugepaged.c
new file mode 100644
index 0000000000..030667cb55
--- /dev/null
+++ b/tools/testing/selftests/mm/khugepaged.c
@@ -0,0 +1,1553 @@
+#define _GNU_SOURCE
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <dirent.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <linux/mman.h>
+#include <sys/mman.h>
+#include <sys/wait.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/sysmacros.h>
+#include <sys/vfs.h>
+
+#include "linux/magic.h"
+
+#include "vm_util.h"
+
+#define BASE_ADDR ((void *)(1UL << 30))
+static unsigned long hpage_pmd_size;
+static unsigned long page_size;
+static int hpage_pmd_nr;
+
+#define THP_SYSFS "/sys/kernel/mm/transparent_hugepage/"
+#define PID_SMAPS "/proc/self/smaps"
+#define TEST_FILE "collapse_test_file"
+
+#define MAX_LINE_LENGTH 500
+
+enum vma_type {
+	VMA_ANON,
+	VMA_FILE,
+	VMA_SHMEM,
+};
+
+struct mem_ops {
+	void *(*setup_area)(int nr_hpages);
+	void (*cleanup_area)(void *p, unsigned long size);
+	void (*fault)(void *p, unsigned long start, unsigned long end);
+	bool (*check_huge)(void *addr, int nr_hpages);
+	const char *name;
+};
+
+static struct mem_ops *file_ops;
+static struct mem_ops *anon_ops;
+static struct mem_ops *shmem_ops;
+
+struct collapse_context {
+	void (*collapse)(const char *msg, char *p, int nr_hpages,
+			 struct mem_ops *ops, bool expect);
+	bool enforce_pte_scan_limits;
+	const char *name;
+};
+
+static struct collapse_context *khugepaged_context;
+static struct collapse_context *madvise_context;
+
+struct file_info {
+	const char *dir;
+	char path[PATH_MAX];
+	enum vma_type type;
+	int fd;
+	char dev_queue_read_ahead_path[PATH_MAX];
+};
+
+static struct file_info finfo;
+
+enum thp_enabled {
+	THP_ALWAYS,
+	THP_MADVISE,
+	THP_NEVER,
+};
+
+static const char *thp_enabled_strings[] = {
+	"always",
+	"madvise",
+	"never",
+	NULL
+};
+
+enum thp_defrag {
+	THP_DEFRAG_ALWAYS,
+	THP_DEFRAG_DEFER,
+	THP_DEFRAG_DEFER_MADVISE,
+	THP_DEFRAG_MADVISE,
+	THP_DEFRAG_NEVER,
+};
+
+static const char *thp_defrag_strings[] = {
+	"always",
+	"defer",
+	"defer+madvise",
+	"madvise",
+	"never",
+	NULL
+};
+
+enum shmem_enabled {
+	SHMEM_ALWAYS,
+	SHMEM_WITHIN_SIZE,
+	SHMEM_ADVISE,
+	SHMEM_NEVER,
+	SHMEM_DENY,
+	SHMEM_FORCE,
+};
+
+static const char *shmem_enabled_strings[] = {
+	"always",
+	"within_size",
+	"advise",
+	"never",
+	"deny",
+	"force",
+	NULL
+};
+
+struct khugepaged_settings {
+	bool defrag;
+	unsigned int alloc_sleep_millisecs;
+	unsigned int scan_sleep_millisecs;
+	unsigned int max_ptes_none;
+	unsigned int max_ptes_swap;
+	unsigned int max_ptes_shared;
+	unsigned long pages_to_scan;
+};
+
+struct settings {
+	enum thp_enabled thp_enabled;
+	enum thp_defrag thp_defrag;
+	enum shmem_enabled shmem_enabled;
+	bool use_zero_page;
+	struct khugepaged_settings khugepaged;
+	unsigned long read_ahead_kb;
+};
+
+static struct settings saved_settings;
+static bool skip_settings_restore;
+
+static int exit_status;
+
+static void success(const char *msg)
+{
+	printf(" \e[32m%s\e[0m\n", msg);
+}
+
+static void fail(const char *msg)
+{
+	printf(" \e[31m%s\e[0m\n", msg);
+	exit_status++;
+}
+
+static void skip(const char *msg)
+{
+	printf(" \e[33m%s\e[0m\n", msg);
+}
+
+static int read_file(const char *path, char *buf, size_t buflen)
+{
+	int fd;
+	ssize_t numread;
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1)
+		return 0;
+
+	numread = read(fd, buf, buflen - 1);
+	if (numread < 1) {
+		close(fd);
+		return 0;
+	}
+
+	buf[numread] = '\0';
+	close(fd);
+
+	return (unsigned int) numread;
+}
+
+static int write_file(const char *path, const char *buf, size_t buflen)
+{
+	int fd;
+	ssize_t numwritten;
+
+	fd = open(path, O_WRONLY);
+	if (fd == -1) {
+		printf("open(%s)\n", path);
+		exit(EXIT_FAILURE);
+		return 0;
+	}
+
+	numwritten = write(fd, buf, buflen - 1);
+	close(fd);
+	if (numwritten < 1) {
+		printf("write(%s)\n", buf);
+		exit(EXIT_FAILURE);
+		return 0;
+	}
+
+	return (unsigned int) numwritten;
+}
+
+static int read_string(const char *name, const char *strings[])
+{
+	char path[PATH_MAX];
+	char buf[256];
+	char *c;
+	int ret;
+
+	ret = snprintf(path, PATH_MAX, THP_SYSFS "%s", name);
+	if (ret >= PATH_MAX) {
+		printf("%s: Pathname is too long\n", __func__);
+		exit(EXIT_FAILURE);
+	}
+
+	if (!read_file(path, buf, sizeof(buf))) {
+		perror(path);
+		exit(EXIT_FAILURE);
+	}
+
+	c = strchr(buf, '[');
+	if (!c) {
+		printf("%s: Parse failure\n", __func__);
+		exit(EXIT_FAILURE);
+	}
+
+	c++;
+	memmove(buf, c, sizeof(buf) - (c - buf));
+
+	c = strchr(buf, ']');
+	if (!c) {
+		printf("%s: Parse failure\n", __func__);
+		exit(EXIT_FAILURE);
+	}
+	*c = '\0';
+
+	ret = 0;
+	while (strings[ret]) {
+		if (!strcmp(strings[ret], buf))
+			return ret;
+		ret++;
+	}
+
+	printf("Failed to parse %s\n", name);
+	exit(EXIT_FAILURE);
+}
+
+static void write_string(const char *name, const char *val)
+{
+	char path[PATH_MAX];
+	int ret;
+
+	ret = snprintf(path, PATH_MAX, THP_SYSFS "%s", name);
+	if (ret >= PATH_MAX) {
+		printf("%s: Pathname is too long\n", __func__);
+		exit(EXIT_FAILURE);
+	}
+
+	if (!write_file(path, val, strlen(val) + 1)) {
+		perror(path);
+		exit(EXIT_FAILURE);
+	}
+}
+
+static const unsigned long _read_num(const char *path)
+{
+	char buf[21];
+
+	if (read_file(path, buf, sizeof(buf)) < 0) {
+		perror("read_file(read_num)");
+		exit(EXIT_FAILURE);
+	}
+
+	return strtoul(buf, NULL, 10);
+}
+
+static const unsigned long read_num(const char *name)
+{
+	char path[PATH_MAX];
+	int ret;
+
+	ret = snprintf(path, PATH_MAX, THP_SYSFS "%s", name);
+	if (ret >= PATH_MAX) {
+		printf("%s: Pathname is too long\n", __func__);
+		exit(EXIT_FAILURE);
+	}
+	return _read_num(path);
+}
+
+static void _write_num(const char *path, unsigned long num)
+{
+	char buf[21];
+
+	sprintf(buf, "%ld", num);
+	if (!write_file(path, buf, strlen(buf) + 1)) {
+		perror(path);
+		exit(EXIT_FAILURE);
+	}
+}
+
+static void write_num(const char *name, unsigned long num)
+{
+	char path[PATH_MAX];
+	int ret;
+
+	ret = snprintf(path, PATH_MAX, THP_SYSFS "%s", name);
+	if (ret >= PATH_MAX) {
+		printf("%s: Pathname is too long\n", __func__);
+		exit(EXIT_FAILURE);
+	}
+	_write_num(path, num);
+}
+
+static void write_settings(struct settings *settings)
+{
+	struct khugepaged_settings *khugepaged = &settings->khugepaged;
+
+	write_string("enabled", thp_enabled_strings[settings->thp_enabled]);
+	write_string("defrag", thp_defrag_strings[settings->thp_defrag]);
+	write_string("shmem_enabled",
+			shmem_enabled_strings[settings->shmem_enabled]);
+	write_num("use_zero_page", settings->use_zero_page);
+
+	write_num("khugepaged/defrag", khugepaged->defrag);
+	write_num("khugepaged/alloc_sleep_millisecs",
+			khugepaged->alloc_sleep_millisecs);
+	write_num("khugepaged/scan_sleep_millisecs",
+			khugepaged->scan_sleep_millisecs);
+	write_num("khugepaged/max_ptes_none", khugepaged->max_ptes_none);
+	write_num("khugepaged/max_ptes_swap", khugepaged->max_ptes_swap);
+	write_num("khugepaged/max_ptes_shared", khugepaged->max_ptes_shared);
+	write_num("khugepaged/pages_to_scan", khugepaged->pages_to_scan);
+
+	if (file_ops && finfo.type == VMA_FILE)
+		_write_num(finfo.dev_queue_read_ahead_path,
+			   settings->read_ahead_kb);
+}
+
+#define MAX_SETTINGS_DEPTH 4
+static struct settings settings_stack[MAX_SETTINGS_DEPTH];
+static int settings_index;
+
+static struct settings *current_settings(void)
+{
+	if (!settings_index) {
+		printf("Fail: No settings set");
+		exit(EXIT_FAILURE);
+	}
+	return settings_stack + settings_index - 1;
+}
+
+static void push_settings(struct settings *settings)
+{
+	if (settings_index >= MAX_SETTINGS_DEPTH) {
+		printf("Fail: Settings stack exceeded");
+		exit(EXIT_FAILURE);
+	}
+	settings_stack[settings_index++] = *settings;
+	write_settings(current_settings());
+}
+
+static void pop_settings(void)
+{
+	if (settings_index <= 0) {
+		printf("Fail: Settings stack empty");
+		exit(EXIT_FAILURE);
+	}
+	--settings_index;
+	write_settings(current_settings());
+}
+
+static void restore_settings(int sig)
+{
+	if (skip_settings_restore)
+		goto out;
+
+	printf("Restore THP and khugepaged settings...");
+	write_settings(&saved_settings);
+	success("OK");
+	if (sig)
+		exit(EXIT_FAILURE);
+out:
+	exit(exit_status);
+}
+
+static void save_settings(void)
+{
+	printf("Save THP and khugepaged settings...");
+	saved_settings = (struct settings) {
+		.thp_enabled = read_string("enabled", thp_enabled_strings),
+		.thp_defrag = read_string("defrag", thp_defrag_strings),
+		.shmem_enabled =
+			read_string("shmem_enabled", shmem_enabled_strings),
+		.use_zero_page = read_num("use_zero_page"),
+	};
+	saved_settings.khugepaged = (struct khugepaged_settings) {
+		.defrag = read_num("khugepaged/defrag"),
+		.alloc_sleep_millisecs =
+			read_num("khugepaged/alloc_sleep_millisecs"),
+		.scan_sleep_millisecs =
+			read_num("khugepaged/scan_sleep_millisecs"),
+		.max_ptes_none = read_num("khugepaged/max_ptes_none"),
+		.max_ptes_swap = read_num("khugepaged/max_ptes_swap"),
+		.max_ptes_shared = read_num("khugepaged/max_ptes_shared"),
+		.pages_to_scan = read_num("khugepaged/pages_to_scan"),
+	};
+	if (file_ops && finfo.type == VMA_FILE)
+		saved_settings.read_ahead_kb =
+				_read_num(finfo.dev_queue_read_ahead_path);
+
+	success("OK");
+
+	signal(SIGTERM, restore_settings);
+	signal(SIGINT, restore_settings);
+	signal(SIGHUP, restore_settings);
+	signal(SIGQUIT, restore_settings);
+}
+
+static void get_finfo(const char *dir)
+{
+	struct stat path_stat;
+	struct statfs fs;
+	char buf[1 << 10];
+	char path[PATH_MAX];
+	char *str, *end;
+
+	finfo.dir = dir;
+	stat(finfo.dir, &path_stat);
+	if (!S_ISDIR(path_stat.st_mode)) {
+		printf("%s: Not a directory (%s)\n", __func__, finfo.dir);
+		exit(EXIT_FAILURE);
+	}
+	if (snprintf(finfo.path, sizeof(finfo.path), "%s/" TEST_FILE,
+		     finfo.dir) >= sizeof(finfo.path)) {
+		printf("%s: Pathname is too long\n", __func__);
+		exit(EXIT_FAILURE);
+	}
+	if (statfs(finfo.dir, &fs)) {
+		perror("statfs()");
+		exit(EXIT_FAILURE);
+	}
+	finfo.type = fs.f_type == TMPFS_MAGIC ? VMA_SHMEM : VMA_FILE;
+	if (finfo.type == VMA_SHMEM)
+		return;
+
+	/* Find owning device's queue/read_ahead_kb control */
+	if (snprintf(path, sizeof(path), "/sys/dev/block/%d:%d/uevent",
+		     major(path_stat.st_dev), minor(path_stat.st_dev))
+	    >= sizeof(path)) {
+		printf("%s: Pathname is too long\n", __func__);
+		exit(EXIT_FAILURE);
+	}
+	if (read_file(path, buf, sizeof(buf)) < 0) {
+		perror("read_file(read_num)");
+		exit(EXIT_FAILURE);
+	}
+	if (strstr(buf, "DEVTYPE=disk")) {
+		/* Found it */
+		if (snprintf(finfo.dev_queue_read_ahead_path,
+			     sizeof(finfo.dev_queue_read_ahead_path),
+			     "/sys/dev/block/%d:%d/queue/read_ahead_kb",
+			     major(path_stat.st_dev), minor(path_stat.st_dev))
+		    >= sizeof(finfo.dev_queue_read_ahead_path)) {
+			printf("%s: Pathname is too long\n", __func__);
+			exit(EXIT_FAILURE);
+		}
+		return;
+	}
+	if (!strstr(buf, "DEVTYPE=partition")) {
+		printf("%s: Unknown device type: %s\n", __func__, path);
+		exit(EXIT_FAILURE);
+	}
+	/*
+	 * Partition of block device - need to find actual device.
+	 * Using naming convention that devnameN is partition of
+	 * device devname.
+	 */
+	str = strstr(buf, "DEVNAME=");
+	if (!str) {
+		printf("%s: Could not read: %s", __func__, path);
+		exit(EXIT_FAILURE);
+	}
+	str += 8;
+	end = str;
+	while (*end) {
+		if (isdigit(*end)) {
+			*end = '\0';
+			if (snprintf(finfo.dev_queue_read_ahead_path,
+				     sizeof(finfo.dev_queue_read_ahead_path),
+				     "/sys/block/%s/queue/read_ahead_kb",
+				     str) >= sizeof(finfo.dev_queue_read_ahead_path)) {
+				printf("%s: Pathname is too long\n", __func__);
+				exit(EXIT_FAILURE);
+			}
+			return;
+		}
+		++end;
+	}
+	printf("%s: Could not read: %s\n", __func__, path);
+	exit(EXIT_FAILURE);
+}
+
+static bool check_swap(void *addr, unsigned long size)
+{
+	bool swap = false;
+	int ret;
+	FILE *fp;
+	char buffer[MAX_LINE_LENGTH];
+	char addr_pattern[MAX_LINE_LENGTH];
+
+	ret = snprintf(addr_pattern, MAX_LINE_LENGTH, "%08lx-",
+		       (unsigned long) addr);
+	if (ret >= MAX_LINE_LENGTH) {
+		printf("%s: Pattern is too long\n", __func__);
+		exit(EXIT_FAILURE);
+	}
+
+
+	fp = fopen(PID_SMAPS, "r");
+	if (!fp) {
+		printf("%s: Failed to open file %s\n", __func__, PID_SMAPS);
+		exit(EXIT_FAILURE);
+	}
+	if (!check_for_pattern(fp, addr_pattern, buffer, sizeof(buffer)))
+		goto err_out;
+
+	ret = snprintf(addr_pattern, MAX_LINE_LENGTH, "Swap:%19ld kB",
+		       size >> 10);
+	if (ret >= MAX_LINE_LENGTH) {
+		printf("%s: Pattern is too long\n", __func__);
+		exit(EXIT_FAILURE);
+	}
+	/*
+	 * Fetch the Swap: in the same block and check whether it got
+	 * the expected number of hugeepages next.
+	 */
+	if (!check_for_pattern(fp, "Swap:", buffer, sizeof(buffer)))
+		goto err_out;
+
+	if (strncmp(buffer, addr_pattern, strlen(addr_pattern)))
+		goto err_out;
+
+	swap = true;
+err_out:
+	fclose(fp);
+	return swap;
+}
+
+static void *alloc_mapping(int nr)
+{
+	void *p;
+
+	p = mmap(BASE_ADDR, nr * hpage_pmd_size, PROT_READ | PROT_WRITE,
+		 MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+	if (p != BASE_ADDR) {
+		printf("Failed to allocate VMA at %p\n", BASE_ADDR);
+		exit(EXIT_FAILURE);
+	}
+
+	return p;
+}
+
+static void fill_memory(int *p, unsigned long start, unsigned long end)
+{
+	int i;
+
+	for (i = start / page_size; i < end / page_size; i++)
+		p[i * page_size / sizeof(*p)] = i + 0xdead0000;
+}
+
+/*
+ * MADV_COLLAPSE is a best-effort request and may fail if an internal
+ * resource is temporarily unavailable, in which case it will set errno to
+ * EAGAIN.  In such a case, immediately reattempt the operation one more
+ * time.
+ */
+static int madvise_collapse_retry(void *p, unsigned long size)
+{
+	bool retry = true;
+	int ret;
+
+retry:
+	ret = madvise(p, size, MADV_COLLAPSE);
+	if (ret && errno == EAGAIN && retry) {
+		retry = false;
+		goto retry;
+	}
+	return ret;
+}
+
+/*
+ * Returns pmd-mapped hugepage in VMA marked VM_HUGEPAGE, filled with
+ * validate_memory()'able contents.
+ */
+static void *alloc_hpage(struct mem_ops *ops)
+{
+	void *p = ops->setup_area(1);
+
+	ops->fault(p, 0, hpage_pmd_size);
+
+	/*
+	 * VMA should be neither VM_HUGEPAGE nor VM_NOHUGEPAGE.
+	 * The latter is ineligible for collapse by MADV_COLLAPSE
+	 * while the former might cause MADV_COLLAPSE to race with
+	 * khugepaged on low-load system (like a test machine), which
+	 * would cause MADV_COLLAPSE to fail with EAGAIN.
+	 */
+	printf("Allocate huge page...");
+	if (madvise_collapse_retry(p, hpage_pmd_size)) {
+		perror("madvise(MADV_COLLAPSE)");
+		exit(EXIT_FAILURE);
+	}
+	if (!ops->check_huge(p, 1)) {
+		perror("madvise(MADV_COLLAPSE)");
+		exit(EXIT_FAILURE);
+	}
+	if (madvise(p, hpage_pmd_size, MADV_HUGEPAGE)) {
+		perror("madvise(MADV_HUGEPAGE)");
+		exit(EXIT_FAILURE);
+	}
+	success("OK");
+	return p;
+}
+
+static void validate_memory(int *p, unsigned long start, unsigned long end)
+{
+	int i;
+
+	for (i = start / page_size; i < end / page_size; i++) {
+		if (p[i * page_size / sizeof(*p)] != i + 0xdead0000) {
+			printf("Page %d is corrupted: %#x\n",
+					i, p[i * page_size / sizeof(*p)]);
+			exit(EXIT_FAILURE);
+		}
+	}
+}
+
+static void *anon_setup_area(int nr_hpages)
+{
+	return alloc_mapping(nr_hpages);
+}
+
+static void anon_cleanup_area(void *p, unsigned long size)
+{
+	munmap(p, size);
+}
+
+static void anon_fault(void *p, unsigned long start, unsigned long end)
+{
+	fill_memory(p, start, end);
+}
+
+static bool anon_check_huge(void *addr, int nr_hpages)
+{
+	return check_huge_anon(addr, nr_hpages, hpage_pmd_size);
+}
+
+static void *file_setup_area(int nr_hpages)
+{
+	int fd;
+	void *p;
+	unsigned long size;
+
+	unlink(finfo.path);  /* Cleanup from previous failed tests */
+	printf("Creating %s for collapse%s...", finfo.path,
+	       finfo.type == VMA_SHMEM ? " (tmpfs)" : "");
+	fd = open(finfo.path, O_DSYNC | O_CREAT | O_RDWR | O_TRUNC | O_EXCL,
+		  777);
+	if (fd < 0) {
+		perror("open()");
+		exit(EXIT_FAILURE);
+	}
+
+	size = nr_hpages * hpage_pmd_size;
+	p = alloc_mapping(nr_hpages);
+	fill_memory(p, 0, size);
+	write(fd, p, size);
+	close(fd);
+	munmap(p, size);
+	success("OK");
+
+	printf("Opening %s read only for collapse...", finfo.path);
+	finfo.fd = open(finfo.path, O_RDONLY, 777);
+	if (finfo.fd < 0) {
+		perror("open()");
+		exit(EXIT_FAILURE);
+	}
+	p = mmap(BASE_ADDR, size, PROT_READ | PROT_EXEC,
+		 MAP_PRIVATE, finfo.fd, 0);
+	if (p == MAP_FAILED || p != BASE_ADDR) {
+		perror("mmap()");
+		exit(EXIT_FAILURE);
+	}
+
+	/* Drop page cache */
+	write_file("/proc/sys/vm/drop_caches", "3", 2);
+	success("OK");
+	return p;
+}
+
+static void file_cleanup_area(void *p, unsigned long size)
+{
+	munmap(p, size);
+	close(finfo.fd);
+	unlink(finfo.path);
+}
+
+static void file_fault(void *p, unsigned long start, unsigned long end)
+{
+	if (madvise(((char *)p) + start, end - start, MADV_POPULATE_READ)) {
+		perror("madvise(MADV_POPULATE_READ");
+		exit(EXIT_FAILURE);
+	}
+}
+
+static bool file_check_huge(void *addr, int nr_hpages)
+{
+	switch (finfo.type) {
+	case VMA_FILE:
+		return check_huge_file(addr, nr_hpages, hpage_pmd_size);
+	case VMA_SHMEM:
+		return check_huge_shmem(addr, nr_hpages, hpage_pmd_size);
+	default:
+		exit(EXIT_FAILURE);
+		return false;
+	}
+}
+
+static void *shmem_setup_area(int nr_hpages)
+{
+	void *p;
+	unsigned long size = nr_hpages * hpage_pmd_size;
+
+	finfo.fd = memfd_create("khugepaged-selftest-collapse-shmem", 0);
+	if (finfo.fd < 0)  {
+		perror("memfd_create()");
+		exit(EXIT_FAILURE);
+	}
+	if (ftruncate(finfo.fd, size)) {
+		perror("ftruncate()");
+		exit(EXIT_FAILURE);
+	}
+	p = mmap(BASE_ADDR, size, PROT_READ | PROT_WRITE, MAP_SHARED, finfo.fd,
+		 0);
+	if (p != BASE_ADDR) {
+		perror("mmap()");
+		exit(EXIT_FAILURE);
+	}
+	return p;
+}
+
+static void shmem_cleanup_area(void *p, unsigned long size)
+{
+	munmap(p, size);
+	close(finfo.fd);
+}
+
+static bool shmem_check_huge(void *addr, int nr_hpages)
+{
+	return check_huge_shmem(addr, nr_hpages, hpage_pmd_size);
+}
+
+static struct mem_ops __anon_ops = {
+	.setup_area = &anon_setup_area,
+	.cleanup_area = &anon_cleanup_area,
+	.fault = &anon_fault,
+	.check_huge = &anon_check_huge,
+	.name = "anon",
+};
+
+static struct mem_ops __file_ops = {
+	.setup_area = &file_setup_area,
+	.cleanup_area = &file_cleanup_area,
+	.fault = &file_fault,
+	.check_huge = &file_check_huge,
+	.name = "file",
+};
+
+static struct mem_ops __shmem_ops = {
+	.setup_area = &shmem_setup_area,
+	.cleanup_area = &shmem_cleanup_area,
+	.fault = &anon_fault,
+	.check_huge = &shmem_check_huge,
+	.name = "shmem",
+};
+
+static void __madvise_collapse(const char *msg, char *p, int nr_hpages,
+			       struct mem_ops *ops, bool expect)
+{
+	int ret;
+	struct settings settings = *current_settings();
+
+	printf("%s...", msg);
+
+	/*
+	 * Prevent khugepaged interference and tests that MADV_COLLAPSE
+	 * ignores /sys/kernel/mm/transparent_hugepage/enabled
+	 */
+	settings.thp_enabled = THP_NEVER;
+	settings.shmem_enabled = SHMEM_NEVER;
+	push_settings(&settings);
+
+	/* Clear VM_NOHUGEPAGE */
+	madvise(p, nr_hpages * hpage_pmd_size, MADV_HUGEPAGE);
+	ret = madvise_collapse_retry(p, nr_hpages * hpage_pmd_size);
+	if (((bool)ret) == expect)
+		fail("Fail: Bad return value");
+	else if (!ops->check_huge(p, expect ? nr_hpages : 0))
+		fail("Fail: check_huge()");
+	else
+		success("OK");
+
+	pop_settings();
+}
+
+static void madvise_collapse(const char *msg, char *p, int nr_hpages,
+			     struct mem_ops *ops, bool expect)
+{
+	/* Sanity check */
+	if (!ops->check_huge(p, 0)) {
+		printf("Unexpected huge page\n");
+		exit(EXIT_FAILURE);
+	}
+	__madvise_collapse(msg, p, nr_hpages, ops, expect);
+}
+
+#define TICK 500000
+static bool wait_for_scan(const char *msg, char *p, int nr_hpages,
+			  struct mem_ops *ops)
+{
+	int full_scans;
+	int timeout = 6; /* 3 seconds */
+
+	/* Sanity check */
+	if (!ops->check_huge(p, 0)) {
+		printf("Unexpected huge page\n");
+		exit(EXIT_FAILURE);
+	}
+
+	madvise(p, nr_hpages * hpage_pmd_size, MADV_HUGEPAGE);
+
+	/* Wait until the second full_scan completed */
+	full_scans = read_num("khugepaged/full_scans") + 2;
+
+	printf("%s...", msg);
+	while (timeout--) {
+		if (ops->check_huge(p, nr_hpages))
+			break;
+		if (read_num("khugepaged/full_scans") >= full_scans)
+			break;
+		printf(".");
+		usleep(TICK);
+	}
+
+	madvise(p, nr_hpages * hpage_pmd_size, MADV_NOHUGEPAGE);
+
+	return timeout == -1;
+}
+
+static void khugepaged_collapse(const char *msg, char *p, int nr_hpages,
+				struct mem_ops *ops, bool expect)
+{
+	if (wait_for_scan(msg, p, nr_hpages, ops)) {
+		if (expect)
+			fail("Timeout");
+		else
+			success("OK");
+		return;
+	}
+
+	/*
+	 * For file and shmem memory, khugepaged only retracts pte entries after
+	 * putting the new hugepage in the page cache. The hugepage must be
+	 * subsequently refaulted to install the pmd mapping for the mm.
+	 */
+	if (ops != &__anon_ops)
+		ops->fault(p, 0, nr_hpages * hpage_pmd_size);
+
+	if (ops->check_huge(p, expect ? nr_hpages : 0))
+		success("OK");
+	else
+		fail("Fail");
+}
+
+static struct collapse_context __khugepaged_context = {
+	.collapse = &khugepaged_collapse,
+	.enforce_pte_scan_limits = true,
+	.name = "khugepaged",
+};
+
+static struct collapse_context __madvise_context = {
+	.collapse = &madvise_collapse,
+	.enforce_pte_scan_limits = false,
+	.name = "madvise",
+};
+
+static bool is_tmpfs(struct mem_ops *ops)
+{
+	return ops == &__file_ops && finfo.type == VMA_SHMEM;
+}
+
+static void alloc_at_fault(void)
+{
+	struct settings settings = *current_settings();
+	char *p;
+
+	settings.thp_enabled = THP_ALWAYS;
+	push_settings(&settings);
+
+	p = alloc_mapping(1);
+	*p = 1;
+	printf("Allocate huge page on fault...");
+	if (check_huge_anon(p, 1, hpage_pmd_size))
+		success("OK");
+	else
+		fail("Fail");
+
+	pop_settings();
+
+	madvise(p, page_size, MADV_DONTNEED);
+	printf("Split huge PMD on MADV_DONTNEED...");
+	if (check_huge_anon(p, 0, hpage_pmd_size))
+		success("OK");
+	else
+		fail("Fail");
+	munmap(p, hpage_pmd_size);
+}
+
+static void collapse_full(struct collapse_context *c, struct mem_ops *ops)
+{
+	void *p;
+	int nr_hpages = 4;
+	unsigned long size = nr_hpages * hpage_pmd_size;
+
+	p = ops->setup_area(nr_hpages);
+	ops->fault(p, 0, size);
+	c->collapse("Collapse multiple fully populated PTE table", p, nr_hpages,
+		    ops, true);
+	validate_memory(p, 0, size);
+	ops->cleanup_area(p, size);
+}
+
+static void collapse_empty(struct collapse_context *c, struct mem_ops *ops)
+{
+	void *p;
+
+	p = ops->setup_area(1);
+	c->collapse("Do not collapse empty PTE table", p, 1, ops, false);
+	ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_single_pte_entry(struct collapse_context *c, struct mem_ops *ops)
+{
+	void *p;
+
+	p = ops->setup_area(1);
+	ops->fault(p, 0, page_size);
+	c->collapse("Collapse PTE table with single PTE entry present", p,
+		    1, ops, true);
+	ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_max_ptes_none(struct collapse_context *c, struct mem_ops *ops)
+{
+	int max_ptes_none = hpage_pmd_nr / 2;
+	struct settings settings = *current_settings();
+	void *p;
+
+	settings.khugepaged.max_ptes_none = max_ptes_none;
+	push_settings(&settings);
+
+	p = ops->setup_area(1);
+
+	if (is_tmpfs(ops)) {
+		/* shmem pages always in the page cache */
+		printf("tmpfs...");
+		skip("Skip");
+		goto skip;
+	}
+
+	ops->fault(p, 0, (hpage_pmd_nr - max_ptes_none - 1) * page_size);
+	c->collapse("Maybe collapse with max_ptes_none exceeded", p, 1,
+		    ops, !c->enforce_pte_scan_limits);
+	validate_memory(p, 0, (hpage_pmd_nr - max_ptes_none - 1) * page_size);
+
+	if (c->enforce_pte_scan_limits) {
+		ops->fault(p, 0, (hpage_pmd_nr - max_ptes_none) * page_size);
+		c->collapse("Collapse with max_ptes_none PTEs empty", p, 1, ops,
+			    true);
+		validate_memory(p, 0,
+				(hpage_pmd_nr - max_ptes_none) * page_size);
+	}
+skip:
+	ops->cleanup_area(p, hpage_pmd_size);
+	pop_settings();
+}
+
+static void collapse_swapin_single_pte(struct collapse_context *c, struct mem_ops *ops)
+{
+	void *p;
+
+	p = ops->setup_area(1);
+	ops->fault(p, 0, hpage_pmd_size);
+
+	printf("Swapout one page...");
+	if (madvise(p, page_size, MADV_PAGEOUT)) {
+		perror("madvise(MADV_PAGEOUT)");
+		exit(EXIT_FAILURE);
+	}
+	if (check_swap(p, page_size)) {
+		success("OK");
+	} else {
+		fail("Fail");
+		goto out;
+	}
+
+	c->collapse("Collapse with swapping in single PTE entry", p, 1, ops,
+		    true);
+	validate_memory(p, 0, hpage_pmd_size);
+out:
+	ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_max_ptes_swap(struct collapse_context *c, struct mem_ops *ops)
+{
+	int max_ptes_swap = read_num("khugepaged/max_ptes_swap");
+	void *p;
+
+	p = ops->setup_area(1);
+	ops->fault(p, 0, hpage_pmd_size);
+
+	printf("Swapout %d of %d pages...", max_ptes_swap + 1, hpage_pmd_nr);
+	if (madvise(p, (max_ptes_swap + 1) * page_size, MADV_PAGEOUT)) {
+		perror("madvise(MADV_PAGEOUT)");
+		exit(EXIT_FAILURE);
+	}
+	if (check_swap(p, (max_ptes_swap + 1) * page_size)) {
+		success("OK");
+	} else {
+		fail("Fail");
+		goto out;
+	}
+
+	c->collapse("Maybe collapse with max_ptes_swap exceeded", p, 1, ops,
+		    !c->enforce_pte_scan_limits);
+	validate_memory(p, 0, hpage_pmd_size);
+
+	if (c->enforce_pte_scan_limits) {
+		ops->fault(p, 0, hpage_pmd_size);
+		printf("Swapout %d of %d pages...", max_ptes_swap,
+		       hpage_pmd_nr);
+		if (madvise(p, max_ptes_swap * page_size, MADV_PAGEOUT)) {
+			perror("madvise(MADV_PAGEOUT)");
+			exit(EXIT_FAILURE);
+		}
+		if (check_swap(p, max_ptes_swap * page_size)) {
+			success("OK");
+		} else {
+			fail("Fail");
+			goto out;
+		}
+
+		c->collapse("Collapse with max_ptes_swap pages swapped out", p,
+			    1, ops, true);
+		validate_memory(p, 0, hpage_pmd_size);
+	}
+out:
+	ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_single_pte_entry_compound(struct collapse_context *c, struct mem_ops *ops)
+{
+	void *p;
+
+	p = alloc_hpage(ops);
+
+	if (is_tmpfs(ops)) {
+		/* MADV_DONTNEED won't evict tmpfs pages */
+		printf("tmpfs...");
+		skip("Skip");
+		goto skip;
+	}
+
+	madvise(p, hpage_pmd_size, MADV_NOHUGEPAGE);
+	printf("Split huge page leaving single PTE mapping compound page...");
+	madvise(p + page_size, hpage_pmd_size - page_size, MADV_DONTNEED);
+	if (ops->check_huge(p, 0))
+		success("OK");
+	else
+		fail("Fail");
+
+	c->collapse("Collapse PTE table with single PTE mapping compound page",
+		    p, 1, ops, true);
+	validate_memory(p, 0, page_size);
+skip:
+	ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_full_of_compound(struct collapse_context *c, struct mem_ops *ops)
+{
+	void *p;
+
+	p = alloc_hpage(ops);
+	printf("Split huge page leaving single PTE page table full of compound pages...");
+	madvise(p, page_size, MADV_NOHUGEPAGE);
+	madvise(p, hpage_pmd_size, MADV_NOHUGEPAGE);
+	if (ops->check_huge(p, 0))
+		success("OK");
+	else
+		fail("Fail");
+
+	c->collapse("Collapse PTE table full of compound pages", p, 1, ops,
+		    true);
+	validate_memory(p, 0, hpage_pmd_size);
+	ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_compound_extreme(struct collapse_context *c, struct mem_ops *ops)
+{
+	void *p;
+	int i;
+
+	p = ops->setup_area(1);
+	for (i = 0; i < hpage_pmd_nr; i++) {
+		printf("\rConstruct PTE page table full of different PTE-mapped compound pages %3d/%d...",
+				i + 1, hpage_pmd_nr);
+
+		madvise(BASE_ADDR, hpage_pmd_size, MADV_HUGEPAGE);
+		ops->fault(BASE_ADDR, 0, hpage_pmd_size);
+		if (!ops->check_huge(BASE_ADDR, 1)) {
+			printf("Failed to allocate huge page\n");
+			exit(EXIT_FAILURE);
+		}
+		madvise(BASE_ADDR, hpage_pmd_size, MADV_NOHUGEPAGE);
+
+		p = mremap(BASE_ADDR - i * page_size,
+				i * page_size + hpage_pmd_size,
+				(i + 1) * page_size,
+				MREMAP_MAYMOVE | MREMAP_FIXED,
+				BASE_ADDR + 2 * hpage_pmd_size);
+		if (p == MAP_FAILED) {
+			perror("mremap+unmap");
+			exit(EXIT_FAILURE);
+		}
+
+		p = mremap(BASE_ADDR + 2 * hpage_pmd_size,
+				(i + 1) * page_size,
+				(i + 1) * page_size + hpage_pmd_size,
+				MREMAP_MAYMOVE | MREMAP_FIXED,
+				BASE_ADDR - (i + 1) * page_size);
+		if (p == MAP_FAILED) {
+			perror("mremap+alloc");
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	ops->cleanup_area(BASE_ADDR, hpage_pmd_size);
+	ops->fault(p, 0, hpage_pmd_size);
+	if (!ops->check_huge(p, 1))
+		success("OK");
+	else
+		fail("Fail");
+
+	c->collapse("Collapse PTE table full of different compound pages", p, 1,
+		    ops, true);
+
+	validate_memory(p, 0, hpage_pmd_size);
+	ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_fork(struct collapse_context *c, struct mem_ops *ops)
+{
+	int wstatus;
+	void *p;
+
+	p = ops->setup_area(1);
+
+	printf("Allocate small page...");
+	ops->fault(p, 0, page_size);
+	if (ops->check_huge(p, 0))
+		success("OK");
+	else
+		fail("Fail");
+
+	printf("Share small page over fork()...");
+	if (!fork()) {
+		/* Do not touch settings on child exit */
+		skip_settings_restore = true;
+		exit_status = 0;
+
+		if (ops->check_huge(p, 0))
+			success("OK");
+		else
+			fail("Fail");
+
+		ops->fault(p, page_size, 2 * page_size);
+		c->collapse("Collapse PTE table with single page shared with parent process",
+			    p, 1, ops, true);
+
+		validate_memory(p, 0, page_size);
+		ops->cleanup_area(p, hpage_pmd_size);
+		exit(exit_status);
+	}
+
+	wait(&wstatus);
+	exit_status += WEXITSTATUS(wstatus);
+
+	printf("Check if parent still has small page...");
+	if (ops->check_huge(p, 0))
+		success("OK");
+	else
+		fail("Fail");
+	validate_memory(p, 0, page_size);
+	ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_fork_compound(struct collapse_context *c, struct mem_ops *ops)
+{
+	int wstatus;
+	void *p;
+
+	p = alloc_hpage(ops);
+	printf("Share huge page over fork()...");
+	if (!fork()) {
+		/* Do not touch settings on child exit */
+		skip_settings_restore = true;
+		exit_status = 0;
+
+		if (ops->check_huge(p, 1))
+			success("OK");
+		else
+			fail("Fail");
+
+		printf("Split huge page PMD in child process...");
+		madvise(p, page_size, MADV_NOHUGEPAGE);
+		madvise(p, hpage_pmd_size, MADV_NOHUGEPAGE);
+		if (ops->check_huge(p, 0))
+			success("OK");
+		else
+			fail("Fail");
+		ops->fault(p, 0, page_size);
+
+		write_num("khugepaged/max_ptes_shared", hpage_pmd_nr - 1);
+		c->collapse("Collapse PTE table full of compound pages in child",
+			    p, 1, ops, true);
+		write_num("khugepaged/max_ptes_shared",
+			  current_settings()->khugepaged.max_ptes_shared);
+
+		validate_memory(p, 0, hpage_pmd_size);
+		ops->cleanup_area(p, hpage_pmd_size);
+		exit(exit_status);
+	}
+
+	wait(&wstatus);
+	exit_status += WEXITSTATUS(wstatus);
+
+	printf("Check if parent still has huge page...");
+	if (ops->check_huge(p, 1))
+		success("OK");
+	else
+		fail("Fail");
+	validate_memory(p, 0, hpage_pmd_size);
+	ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_max_ptes_shared(struct collapse_context *c, struct mem_ops *ops)
+{
+	int max_ptes_shared = read_num("khugepaged/max_ptes_shared");
+	int wstatus;
+	void *p;
+
+	p = alloc_hpage(ops);
+	printf("Share huge page over fork()...");
+	if (!fork()) {
+		/* Do not touch settings on child exit */
+		skip_settings_restore = true;
+		exit_status = 0;
+
+		if (ops->check_huge(p, 1))
+			success("OK");
+		else
+			fail("Fail");
+
+		printf("Trigger CoW on page %d of %d...",
+				hpage_pmd_nr - max_ptes_shared - 1, hpage_pmd_nr);
+		ops->fault(p, 0, (hpage_pmd_nr - max_ptes_shared - 1) * page_size);
+		if (ops->check_huge(p, 0))
+			success("OK");
+		else
+			fail("Fail");
+
+		c->collapse("Maybe collapse with max_ptes_shared exceeded", p,
+			    1, ops, !c->enforce_pte_scan_limits);
+
+		if (c->enforce_pte_scan_limits) {
+			printf("Trigger CoW on page %d of %d...",
+			       hpage_pmd_nr - max_ptes_shared, hpage_pmd_nr);
+			ops->fault(p, 0, (hpage_pmd_nr - max_ptes_shared) *
+				    page_size);
+			if (ops->check_huge(p, 0))
+				success("OK");
+			else
+				fail("Fail");
+
+			c->collapse("Collapse with max_ptes_shared PTEs shared",
+				    p, 1, ops, true);
+		}
+
+		validate_memory(p, 0, hpage_pmd_size);
+		ops->cleanup_area(p, hpage_pmd_size);
+		exit(exit_status);
+	}
+
+	wait(&wstatus);
+	exit_status += WEXITSTATUS(wstatus);
+
+	printf("Check if parent still has huge page...");
+	if (ops->check_huge(p, 1))
+		success("OK");
+	else
+		fail("Fail");
+	validate_memory(p, 0, hpage_pmd_size);
+	ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void madvise_collapse_existing_thps(struct collapse_context *c,
+					   struct mem_ops *ops)
+{
+	void *p;
+
+	p = ops->setup_area(1);
+	ops->fault(p, 0, hpage_pmd_size);
+	c->collapse("Collapse fully populated PTE table...", p, 1, ops, true);
+	validate_memory(p, 0, hpage_pmd_size);
+
+	/* c->collapse() will find a hugepage and complain - call directly. */
+	__madvise_collapse("Re-collapse PMD-mapped hugepage", p, 1, ops, true);
+	validate_memory(p, 0, hpage_pmd_size);
+	ops->cleanup_area(p, hpage_pmd_size);
+}
+
+/*
+ * Test race with khugepaged where page tables have been retracted and
+ * pmd cleared.
+ */
+static void madvise_retracted_page_tables(struct collapse_context *c,
+					  struct mem_ops *ops)
+{
+	void *p;
+	int nr_hpages = 1;
+	unsigned long size = nr_hpages * hpage_pmd_size;
+
+	p = ops->setup_area(nr_hpages);
+	ops->fault(p, 0, size);
+
+	/* Let khugepaged collapse and leave pmd cleared */
+	if (wait_for_scan("Collapse and leave PMD cleared", p, nr_hpages,
+			  ops)) {
+		fail("Timeout");
+		return;
+	}
+	success("OK");
+	c->collapse("Install huge PMD from page cache", p, nr_hpages, ops,
+		    true);
+	validate_memory(p, 0, size);
+	ops->cleanup_area(p, size);
+}
+
+static void usage(void)
+{
+	fprintf(stderr, "\nUsage: ./khugepaged <test type> [dir]\n\n");
+	fprintf(stderr, "\t<test type>\t: <context>:<mem_type>\n");
+	fprintf(stderr, "\t<context>\t: [all|khugepaged|madvise]\n");
+	fprintf(stderr, "\t<mem_type>\t: [all|anon|file|shmem]\n");
+	fprintf(stderr, "\n\t\"file,all\" mem_type requires [dir] argument\n");
+	fprintf(stderr, "\n\t\"file,all\" mem_type requires kernel built with\n");
+	fprintf(stderr,	"\tCONFIG_READ_ONLY_THP_FOR_FS=y\n");
+	fprintf(stderr, "\n\tif [dir] is a (sub)directory of a tmpfs mount, tmpfs must be\n");
+	fprintf(stderr,	"\tmounted with huge=madvise option for khugepaged tests to work\n");
+	exit(1);
+}
+
+static void parse_test_type(int argc, const char **argv)
+{
+	char *buf;
+	const char *token;
+
+	if (argc == 1) {
+		/* Backwards compatibility */
+		khugepaged_context =  &__khugepaged_context;
+		madvise_context =  &__madvise_context;
+		anon_ops = &__anon_ops;
+		return;
+	}
+
+	buf = strdup(argv[1]);
+	token = strsep(&buf, ":");
+
+	if (!strcmp(token, "all")) {
+		khugepaged_context =  &__khugepaged_context;
+		madvise_context =  &__madvise_context;
+	} else if (!strcmp(token, "khugepaged")) {
+		khugepaged_context =  &__khugepaged_context;
+	} else if (!strcmp(token, "madvise")) {
+		madvise_context =  &__madvise_context;
+	} else {
+		usage();
+	}
+
+	if (!buf)
+		usage();
+
+	if (!strcmp(buf, "all")) {
+		file_ops =  &__file_ops;
+		anon_ops = &__anon_ops;
+		shmem_ops = &__shmem_ops;
+	} else if (!strcmp(buf, "anon")) {
+		anon_ops = &__anon_ops;
+	} else if (!strcmp(buf, "file")) {
+		file_ops =  &__file_ops;
+	} else if (!strcmp(buf, "shmem")) {
+		shmem_ops = &__shmem_ops;
+	} else {
+		usage();
+	}
+
+	if (!file_ops)
+		return;
+
+	if (argc != 3)
+		usage();
+}
+
+int main(int argc, const char **argv)
+{
+	struct settings default_settings = {
+		.thp_enabled = THP_MADVISE,
+		.thp_defrag = THP_DEFRAG_ALWAYS,
+		.shmem_enabled = SHMEM_ADVISE,
+		.use_zero_page = 0,
+		.khugepaged = {
+			.defrag = 1,
+			.alloc_sleep_millisecs = 10,
+			.scan_sleep_millisecs = 10,
+		},
+		/*
+		 * When testing file-backed memory, the collapse path
+		 * looks at how many pages are found in the page cache, not
+		 * what pages are mapped. Disable read ahead optimization so
+		 * pages don't find their way into the page cache unless
+		 * we mem_ops->fault() them in.
+		 */
+		.read_ahead_kb = 0,
+	};
+
+	parse_test_type(argc, argv);
+
+	if (file_ops)
+		get_finfo(argv[2]);
+
+	setbuf(stdout, NULL);
+
+	page_size = getpagesize();
+	hpage_pmd_size = read_pmd_pagesize();
+	if (!hpage_pmd_size) {
+		printf("Reading PMD pagesize failed");
+		exit(EXIT_FAILURE);
+	}
+	hpage_pmd_nr = hpage_pmd_size / page_size;
+
+	default_settings.khugepaged.max_ptes_none = hpage_pmd_nr - 1;
+	default_settings.khugepaged.max_ptes_swap = hpage_pmd_nr / 8;
+	default_settings.khugepaged.max_ptes_shared = hpage_pmd_nr / 2;
+	default_settings.khugepaged.pages_to_scan = hpage_pmd_nr * 8;
+
+	save_settings();
+	push_settings(&default_settings);
+
+	alloc_at_fault();
+
+#define TEST(t, c, o) do { \
+	if (c && o) { \
+		printf("\nRun test: " #t " (%s:%s)\n", c->name, o->name); \
+		t(c, o); \
+	} \
+	} while (0)
+
+	TEST(collapse_full, khugepaged_context, anon_ops);
+	TEST(collapse_full, khugepaged_context, file_ops);
+	TEST(collapse_full, khugepaged_context, shmem_ops);
+	TEST(collapse_full, madvise_context, anon_ops);
+	TEST(collapse_full, madvise_context, file_ops);
+	TEST(collapse_full, madvise_context, shmem_ops);
+
+	TEST(collapse_empty, khugepaged_context, anon_ops);
+	TEST(collapse_empty, madvise_context, anon_ops);
+
+	TEST(collapse_single_pte_entry, khugepaged_context, anon_ops);
+	TEST(collapse_single_pte_entry, khugepaged_context, file_ops);
+	TEST(collapse_single_pte_entry, khugepaged_context, shmem_ops);
+	TEST(collapse_single_pte_entry, madvise_context, anon_ops);
+	TEST(collapse_single_pte_entry, madvise_context, file_ops);
+	TEST(collapse_single_pte_entry, madvise_context, shmem_ops);
+
+	TEST(collapse_max_ptes_none, khugepaged_context, anon_ops);
+	TEST(collapse_max_ptes_none, khugepaged_context, file_ops);
+	TEST(collapse_max_ptes_none, madvise_context, anon_ops);
+	TEST(collapse_max_ptes_none, madvise_context, file_ops);
+
+	TEST(collapse_single_pte_entry_compound, khugepaged_context, anon_ops);
+	TEST(collapse_single_pte_entry_compound, khugepaged_context, file_ops);
+	TEST(collapse_single_pte_entry_compound, madvise_context, anon_ops);
+	TEST(collapse_single_pte_entry_compound, madvise_context, file_ops);
+
+	TEST(collapse_full_of_compound, khugepaged_context, anon_ops);
+	TEST(collapse_full_of_compound, khugepaged_context, file_ops);
+	TEST(collapse_full_of_compound, khugepaged_context, shmem_ops);
+	TEST(collapse_full_of_compound, madvise_context, anon_ops);
+	TEST(collapse_full_of_compound, madvise_context, file_ops);
+	TEST(collapse_full_of_compound, madvise_context, shmem_ops);
+
+	TEST(collapse_compound_extreme, khugepaged_context, anon_ops);
+	TEST(collapse_compound_extreme, madvise_context, anon_ops);
+
+	TEST(collapse_swapin_single_pte, khugepaged_context, anon_ops);
+	TEST(collapse_swapin_single_pte, madvise_context, anon_ops);
+
+	TEST(collapse_max_ptes_swap, khugepaged_context, anon_ops);
+	TEST(collapse_max_ptes_swap, madvise_context, anon_ops);
+
+	TEST(collapse_fork, khugepaged_context, anon_ops);
+	TEST(collapse_fork, madvise_context, anon_ops);
+
+	TEST(collapse_fork_compound, khugepaged_context, anon_ops);
+	TEST(collapse_fork_compound, madvise_context, anon_ops);
+
+	TEST(collapse_max_ptes_shared, khugepaged_context, anon_ops);
+	TEST(collapse_max_ptes_shared, madvise_context, anon_ops);
+
+	TEST(madvise_collapse_existing_thps, madvise_context, anon_ops);
+	TEST(madvise_collapse_existing_thps, madvise_context, file_ops);
+	TEST(madvise_collapse_existing_thps, madvise_context, shmem_ops);
+
+	TEST(madvise_retracted_page_tables, madvise_context, file_ops);
+	TEST(madvise_retracted_page_tables, madvise_context, shmem_ops);
+
+	restore_settings(0);
+}