brintos

brintos / linux-shallow public Read only

0
0
Text · 26.0 KiB · b748c48 Raw
949 lines · c
1// SPDX-License-Identifier: GPL-2.02 3#include <sys/mman.h>4#include <sys/prctl.h>5#include <sys/wait.h>6#include <stdbool.h>7#include <time.h>8#include <string.h>9#include <numa.h>10#include <unistd.h>11#include <fcntl.h>12#include <stdint.h>13#include <err.h>14 15#include "../kselftest.h"16#include <include/vdso/time64.h>17#include "vm_util.h"18 19#define KSM_SYSFS_PATH "/sys/kernel/mm/ksm/"20#define KSM_FP(s) (KSM_SYSFS_PATH s)21#define KSM_SCAN_LIMIT_SEC_DEFAULT 12022#define KSM_PAGE_COUNT_DEFAULT 10l23#define KSM_PROT_STR_DEFAULT "rw"24#define KSM_USE_ZERO_PAGES_DEFAULT false25#define KSM_MERGE_ACROSS_NODES_DEFAULT true26#define KSM_MERGE_TYPE_DEFAULT 027#define MB (1ul << 20)28 29struct ksm_sysfs {30	unsigned long max_page_sharing;31	unsigned long merge_across_nodes;32	unsigned long pages_to_scan;33	unsigned long run;34	unsigned long sleep_millisecs;35	unsigned long stable_node_chains_prune_millisecs;36	unsigned long use_zero_pages;37};38 39enum ksm_merge_type {40	KSM_MERGE_MADVISE,41	KSM_MERGE_PRCTL,42	KSM_MERGE_LAST = KSM_MERGE_PRCTL43};44 45enum ksm_test_name {46	CHECK_KSM_MERGE,47	CHECK_KSM_UNMERGE,48	CHECK_KSM_GET_MERGE_TYPE,49	CHECK_KSM_ZERO_PAGE_MERGE,50	CHECK_KSM_NUMA_MERGE,51	KSM_MERGE_TIME,52	KSM_MERGE_TIME_HUGE_PAGES,53	KSM_UNMERGE_TIME,54	KSM_COW_TIME55};56 57int debug;58 59static int ksm_write_sysfs(const char *file_path, unsigned long val)60{61	FILE *f = fopen(file_path, "w");62 63	if (!f) {64		fprintf(stderr, "f %s\n", file_path);65		perror("fopen");66		return 1;67	}68	if (fprintf(f, "%lu", val) < 0) {69		perror("fprintf");70		fclose(f);71		return 1;72	}73	fclose(f);74 75	return 0;76}77 78static int ksm_read_sysfs(const char *file_path, unsigned long *val)79{80	FILE *f = fopen(file_path, "r");81 82	if (!f) {83		fprintf(stderr, "f %s\n", file_path);84		perror("fopen");85		return 1;86	}87	if (fscanf(f, "%lu", val) != 1) {88		perror("fscanf");89		fclose(f);90		return 1;91	}92	fclose(f);93 94	return 0;95}96 97static void ksm_print_sysfs(void)98{99	unsigned long max_page_sharing, pages_sharing, pages_shared;100	unsigned long full_scans, pages_unshared, pages_volatile;101	unsigned long stable_node_chains, stable_node_dups;102	long general_profit;103 104	if (ksm_read_sysfs(KSM_FP("pages_shared"), &pages_shared) ||105	    ksm_read_sysfs(KSM_FP("pages_sharing"), &pages_sharing) ||106	    ksm_read_sysfs(KSM_FP("max_page_sharing"), &max_page_sharing) ||107	    ksm_read_sysfs(KSM_FP("full_scans"), &full_scans) ||108	    ksm_read_sysfs(KSM_FP("pages_unshared"), &pages_unshared) ||109	    ksm_read_sysfs(KSM_FP("pages_volatile"), &pages_volatile) ||110	    ksm_read_sysfs(KSM_FP("stable_node_chains"), &stable_node_chains) ||111	    ksm_read_sysfs(KSM_FP("stable_node_dups"), &stable_node_dups) ||112	    ksm_read_sysfs(KSM_FP("general_profit"), (unsigned long *)&general_profit))113		return;114 115	printf("pages_shared      : %lu\n", pages_shared);116	printf("pages_sharing     : %lu\n", pages_sharing);117	printf("max_page_sharing  : %lu\n", max_page_sharing);118	printf("full_scans        : %lu\n", full_scans);119	printf("pages_unshared    : %lu\n", pages_unshared);120	printf("pages_volatile    : %lu\n", pages_volatile);121	printf("stable_node_chains: %lu\n", stable_node_chains);122	printf("stable_node_dups  : %lu\n", stable_node_dups);123	printf("general_profit    : %ld\n", general_profit);124}125 126static void ksm_print_procfs(void)127{128	const char *file_name = "/proc/self/ksm_stat";129	char buffer[512];130	FILE *f = fopen(file_name, "r");131 132	if (!f) {133		fprintf(stderr, "f %s\n", file_name);134		perror("fopen");135		return;136	}137 138	while (fgets(buffer, sizeof(buffer), f))139		printf("%s", buffer);140 141	fclose(f);142}143 144static int str_to_prot(char *prot_str)145{146	int prot = 0;147 148	if ((strchr(prot_str, 'r')) != NULL)149		prot |= PROT_READ;150	if ((strchr(prot_str, 'w')) != NULL)151		prot |= PROT_WRITE;152	if ((strchr(prot_str, 'x')) != NULL)153		prot |= PROT_EXEC;154 155	return prot;156}157 158static void print_help(void)159{160	printf("usage: ksm_tests [-h] <test type> [-a prot] [-p page_count] [-l timeout]\n"161	       "[-z use_zero_pages] [-m merge_across_nodes] [-s size]\n");162 163	printf("Supported <test type>:\n"164	       " -M (page merging)\n"165	       " -Z (zero pages merging)\n"166	       " -N (merging of pages in different NUMA nodes)\n"167	       " -U (page unmerging)\n"168	       " -P evaluate merging time and speed.\n"169	       "    For this test, the size of duplicated memory area (in MiB)\n"170	       "    must be provided using -s option\n"171	       " -H evaluate merging time and speed of area allocated mostly with huge pages\n"172	       "    For this test, the size of duplicated memory area (in MiB)\n"173	       "    must be provided using -s option\n"174	       " -D evaluate unmerging time and speed when disabling KSM.\n"175	       "    For this test, the size of duplicated memory area (in MiB)\n"176	       "    must be provided using -s option\n"177	       " -C evaluate the time required to break COW of merged pages.\n\n");178 179	printf(" -a: specify the access protections of pages.\n"180	       "     <prot> must be of the form [rwx].\n"181	       "     Default: %s\n", KSM_PROT_STR_DEFAULT);182	printf(" -p: specify the number of pages to test.\n"183	       "     Default: %ld\n", KSM_PAGE_COUNT_DEFAULT);184	printf(" -l: limit the maximum running time (in seconds) for a test.\n"185	       "     Default: %d seconds\n", KSM_SCAN_LIMIT_SEC_DEFAULT);186	printf(" -z: change use_zero_pages tunable\n"187	       "     Default: %d\n", KSM_USE_ZERO_PAGES_DEFAULT);188	printf(" -m: change merge_across_nodes tunable\n"189	       "     Default: %d\n", KSM_MERGE_ACROSS_NODES_DEFAULT);190	printf(" -d: turn debugging output on\n");191	printf(" -s: the size of duplicated memory area (in MiB)\n");192	printf(" -t: KSM merge type\n"193	       "     Default: 0\n"194	       "     0: madvise merging\n"195	       "     1: prctl merging\n");196 197	exit(0);198}199 200static void  *allocate_memory(void *ptr, int prot, int mapping, char data, size_t map_size)201{202	void *map_ptr = mmap(ptr, map_size, PROT_WRITE, mapping, -1, 0);203 204	if (!map_ptr) {205		perror("mmap");206		return NULL;207	}208	memset(map_ptr, data, map_size);209	if (mprotect(map_ptr, map_size, prot)) {210		perror("mprotect");211		munmap(map_ptr, map_size);212		return NULL;213	}214 215	return map_ptr;216}217 218static int ksm_do_scan(int scan_count, struct timespec start_time, int timeout)219{220	struct timespec cur_time;221	unsigned long cur_scan, init_scan;222 223	if (ksm_read_sysfs(KSM_FP("full_scans"), &init_scan))224		return 1;225	cur_scan = init_scan;226 227	while (cur_scan < init_scan + scan_count) {228		if (ksm_read_sysfs(KSM_FP("full_scans"), &cur_scan))229			return 1;230		if (clock_gettime(CLOCK_MONOTONIC_RAW, &cur_time)) {231			perror("clock_gettime");232			return 1;233		}234		if ((cur_time.tv_sec - start_time.tv_sec) > timeout) {235			printf("Scan time limit exceeded\n");236			return 1;237		}238	}239 240	return 0;241}242 243static int ksm_merge_pages(int merge_type, void *addr, size_t size,244			struct timespec start_time, int timeout)245{246	if (merge_type == KSM_MERGE_MADVISE) {247		if (madvise(addr, size, MADV_MERGEABLE)) {248			perror("madvise");249			return 1;250		}251	} else if (merge_type == KSM_MERGE_PRCTL) {252		if (prctl(PR_SET_MEMORY_MERGE, 1, 0, 0, 0)) {253			perror("prctl");254			return 1;255		}256	}257 258	if (ksm_write_sysfs(KSM_FP("run"), 1))259		return 1;260 261	/* Since merging occurs only after 2 scans, make sure to get at least 2 full scans */262	if (ksm_do_scan(2, start_time, timeout))263		return 1;264 265	return 0;266}267 268static int ksm_unmerge_pages(void *addr, size_t size,269			     struct timespec start_time, int timeout)270{271	if (madvise(addr, size, MADV_UNMERGEABLE)) {272		perror("madvise");273		return 1;274	}275	return 0;276}277 278static bool assert_ksm_pages_count(long dupl_page_count)279{280	unsigned long max_page_sharing, pages_sharing, pages_shared;281 282	if (ksm_read_sysfs(KSM_FP("pages_shared"), &pages_shared) ||283	    ksm_read_sysfs(KSM_FP("pages_sharing"), &pages_sharing) ||284	    ksm_read_sysfs(KSM_FP("max_page_sharing"), &max_page_sharing))285		return false;286 287	if (debug) {288		ksm_print_sysfs();289		ksm_print_procfs();290	}291 292	/*293	 * Since there must be at least 2 pages for merging and 1 page can be294	 * shared with the limited number of pages (max_page_sharing), sometimes295	 * there are 'leftover' pages that cannot be merged. For example, if there296	 * are 11 pages and max_page_sharing = 10, then only 10 pages will be297	 * merged and the 11th page won't be affected. As a result, when the number298	 * of duplicate pages is divided by max_page_sharing and the remainder is 1,299	 * pages_shared and pages_sharing values will be equal between dupl_page_count300	 * and dupl_page_count - 1.301	 */302	if (dupl_page_count % max_page_sharing == 1 || dupl_page_count % max_page_sharing == 0) {303		if (pages_shared == dupl_page_count / max_page_sharing &&304		    pages_sharing == pages_shared * (max_page_sharing - 1))305			return true;306	} else {307		if (pages_shared == (dupl_page_count / max_page_sharing + 1) &&308		    pages_sharing == dupl_page_count - pages_shared)309			return true;310	}311 312	return false;313}314 315static int ksm_save_def(struct ksm_sysfs *ksm_sysfs)316{317	if (ksm_read_sysfs(KSM_FP("max_page_sharing"), &ksm_sysfs->max_page_sharing) ||318	    numa_available() ? 0 :319		ksm_read_sysfs(KSM_FP("merge_across_nodes"), &ksm_sysfs->merge_across_nodes) ||320	    ksm_read_sysfs(KSM_FP("sleep_millisecs"), &ksm_sysfs->sleep_millisecs) ||321	    ksm_read_sysfs(KSM_FP("pages_to_scan"), &ksm_sysfs->pages_to_scan) ||322	    ksm_read_sysfs(KSM_FP("run"), &ksm_sysfs->run) ||323	    ksm_read_sysfs(KSM_FP("stable_node_chains_prune_millisecs"),324			   &ksm_sysfs->stable_node_chains_prune_millisecs) ||325	    ksm_read_sysfs(KSM_FP("use_zero_pages"), &ksm_sysfs->use_zero_pages))326		return 1;327 328	return 0;329}330 331static int ksm_restore(struct ksm_sysfs *ksm_sysfs)332{333	if (ksm_write_sysfs(KSM_FP("max_page_sharing"), ksm_sysfs->max_page_sharing) ||334	    numa_available() ? 0 :335		ksm_write_sysfs(KSM_FP("merge_across_nodes"), ksm_sysfs->merge_across_nodes) ||336	    ksm_write_sysfs(KSM_FP("pages_to_scan"), ksm_sysfs->pages_to_scan) ||337	    ksm_write_sysfs(KSM_FP("run"), ksm_sysfs->run) ||338	    ksm_write_sysfs(KSM_FP("sleep_millisecs"), ksm_sysfs->sleep_millisecs) ||339	    ksm_write_sysfs(KSM_FP("stable_node_chains_prune_millisecs"),340			    ksm_sysfs->stable_node_chains_prune_millisecs) ||341	    ksm_write_sysfs(KSM_FP("use_zero_pages"), ksm_sysfs->use_zero_pages))342		return 1;343 344	return 0;345}346 347static int check_ksm_merge(int merge_type, int mapping, int prot,348			long page_count, int timeout, size_t page_size)349{350	void *map_ptr;351	struct timespec start_time;352 353	if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {354		perror("clock_gettime");355		return KSFT_FAIL;356	}357 358	/* fill pages with the same data and merge them */359	map_ptr = allocate_memory(NULL, prot, mapping, '*', page_size * page_count);360	if (!map_ptr)361		return KSFT_FAIL;362 363	if (ksm_merge_pages(merge_type, map_ptr, page_size * page_count, start_time, timeout))364		goto err_out;365 366	/* verify that the right number of pages are merged */367	if (assert_ksm_pages_count(page_count)) {368		printf("OK\n");369		munmap(map_ptr, page_size * page_count);370		if (merge_type == KSM_MERGE_PRCTL)371			prctl(PR_SET_MEMORY_MERGE, 0, 0, 0, 0);372		return KSFT_PASS;373	}374 375err_out:376	printf("Not OK\n");377	munmap(map_ptr, page_size * page_count);378	return KSFT_FAIL;379}380 381static int check_ksm_unmerge(int merge_type, int mapping, int prot, int timeout, size_t page_size)382{383	void *map_ptr;384	struct timespec start_time;385	int page_count = 2;386 387	if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {388		perror("clock_gettime");389		return KSFT_FAIL;390	}391 392	/* fill pages with the same data and merge them */393	map_ptr = allocate_memory(NULL, prot, mapping, '*', page_size * page_count);394	if (!map_ptr)395		return KSFT_FAIL;396 397	if (ksm_merge_pages(merge_type, map_ptr, page_size * page_count, start_time, timeout))398		goto err_out;399 400	/* change 1 byte in each of the 2 pages -- KSM must automatically unmerge them */401	memset(map_ptr, '-', 1);402	memset(map_ptr + page_size, '+', 1);403 404	/* get at least 1 scan, so KSM can detect that the pages were modified */405	if (ksm_do_scan(1, start_time, timeout))406		goto err_out;407 408	/* check that unmerging was successful and 0 pages are currently merged */409	if (assert_ksm_pages_count(0)) {410		printf("OK\n");411		munmap(map_ptr, page_size * page_count);412		return KSFT_PASS;413	}414 415err_out:416	printf("Not OK\n");417	munmap(map_ptr, page_size * page_count);418	return KSFT_FAIL;419}420 421static int check_ksm_zero_page_merge(int merge_type, int mapping, int prot, long page_count,422				int timeout, bool use_zero_pages, size_t page_size)423{424	void *map_ptr;425	struct timespec start_time;426 427	if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {428		perror("clock_gettime");429		return KSFT_FAIL;430	}431 432	if (ksm_write_sysfs(KSM_FP("use_zero_pages"), use_zero_pages))433		return KSFT_FAIL;434 435	/* fill pages with zero and try to merge them */436	map_ptr = allocate_memory(NULL, prot, mapping, 0, page_size * page_count);437	if (!map_ptr)438		return KSFT_FAIL;439 440	if (ksm_merge_pages(merge_type, map_ptr, page_size * page_count, start_time, timeout))441		goto err_out;442 443       /*444	* verify that the right number of pages are merged:445	* 1) if use_zero_pages is set to 1, empty pages are merged446	*    with the kernel zero page instead of with each other;447	* 2) if use_zero_pages is set to 0, empty pages are not treated specially448	*    and merged as usual.449	*/450	if (use_zero_pages && !assert_ksm_pages_count(0))451		goto err_out;452	else if (!use_zero_pages && !assert_ksm_pages_count(page_count))453		goto err_out;454 455	printf("OK\n");456	munmap(map_ptr, page_size * page_count);457	return KSFT_PASS;458 459err_out:460	printf("Not OK\n");461	munmap(map_ptr, page_size * page_count);462	return KSFT_FAIL;463}464 465static int get_next_mem_node(int node)466{467 468	long node_size;469	int mem_node = 0;470	int i, max_node = numa_max_node();471 472	for (i = node + 1; i <= max_node + node; i++) {473		mem_node = i % (max_node + 1);474		node_size = numa_node_size(mem_node, NULL);475		if (node_size > 0)476			break;477	}478	return mem_node;479}480 481static int get_first_mem_node(void)482{483	return get_next_mem_node(numa_max_node());484}485 486static int check_ksm_numa_merge(int merge_type, int mapping, int prot, int timeout,487				bool merge_across_nodes, size_t page_size)488{489	void *numa1_map_ptr, *numa2_map_ptr;490	struct timespec start_time;491	int page_count = 2;492	int first_node;493 494	if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {495		perror("clock_gettime");496		return KSFT_FAIL;497	}498 499	if (numa_available() < 0) {500		perror("NUMA support not enabled");501		return KSFT_SKIP;502	}503	if (numa_num_configured_nodes() <= 1) {504		printf("At least 2 NUMA nodes must be available\n");505		return KSFT_SKIP;506	}507	if (ksm_write_sysfs(KSM_FP("merge_across_nodes"), merge_across_nodes))508		return KSFT_FAIL;509 510	/* allocate 2 pages in 2 different NUMA nodes and fill them with the same data */511	first_node = get_first_mem_node();512	numa1_map_ptr = numa_alloc_onnode(page_size, first_node);513	numa2_map_ptr = numa_alloc_onnode(page_size, get_next_mem_node(first_node));514	if (!numa1_map_ptr || !numa2_map_ptr) {515		perror("numa_alloc_onnode");516		return KSFT_FAIL;517	}518 519	memset(numa1_map_ptr, '*', page_size);520	memset(numa2_map_ptr, '*', page_size);521 522	/* try to merge the pages */523	if (ksm_merge_pages(merge_type, numa1_map_ptr, page_size, start_time, timeout) ||524	    ksm_merge_pages(merge_type, numa2_map_ptr, page_size, start_time, timeout))525		goto err_out;526 527       /*528	* verify that the right number of pages are merged:529	* 1) if merge_across_nodes was enabled, 2 duplicate pages will be merged;530	* 2) if merge_across_nodes = 0, there must be 0 merged pages, since there is531	*    only 1 unique page in each node and they can't be shared.532	*/533	if (merge_across_nodes && !assert_ksm_pages_count(page_count))534		goto err_out;535	else if (!merge_across_nodes && !assert_ksm_pages_count(0))536		goto err_out;537 538	numa_free(numa1_map_ptr, page_size);539	numa_free(numa2_map_ptr, page_size);540	printf("OK\n");541	return KSFT_PASS;542 543err_out:544	numa_free(numa1_map_ptr, page_size);545	numa_free(numa2_map_ptr, page_size);546	printf("Not OK\n");547	return KSFT_FAIL;548}549 550static int ksm_merge_hugepages_time(int merge_type, int mapping, int prot,551				int timeout, size_t map_size)552{553	void *map_ptr, *map_ptr_orig;554	struct timespec start_time, end_time;555	unsigned long scan_time_ns;556	int pagemap_fd, n_normal_pages, n_huge_pages;557 558	map_size *= MB;559	size_t len = map_size;560 561	len -= len % HPAGE_SIZE;562	map_ptr_orig = mmap(NULL, len + HPAGE_SIZE, PROT_READ | PROT_WRITE,563			MAP_ANONYMOUS | MAP_NORESERVE | MAP_PRIVATE, -1, 0);564	map_ptr = map_ptr_orig + HPAGE_SIZE - (uintptr_t)map_ptr_orig % HPAGE_SIZE;565 566	if (map_ptr_orig == MAP_FAILED)567		err(2, "initial mmap");568 569	if (madvise(map_ptr, len, MADV_HUGEPAGE))570		err(2, "MADV_HUGEPAGE");571 572	pagemap_fd = open("/proc/self/pagemap", O_RDONLY);573	if (pagemap_fd < 0)574		err(2, "open pagemap");575 576	n_normal_pages = 0;577	n_huge_pages = 0;578	for (void *p = map_ptr; p < map_ptr + len; p += HPAGE_SIZE) {579		if (allocate_transhuge(p, pagemap_fd) < 0)580			n_normal_pages++;581		else582			n_huge_pages++;583	}584	printf("Number of normal pages:    %d\n", n_normal_pages);585	printf("Number of huge pages:    %d\n", n_huge_pages);586 587	memset(map_ptr, '*', len);588 589	if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {590		perror("clock_gettime");591		goto err_out;592	}593	if (ksm_merge_pages(merge_type, map_ptr, map_size, start_time, timeout))594		goto err_out;595	if (clock_gettime(CLOCK_MONOTONIC_RAW, &end_time)) {596		perror("clock_gettime");597		goto err_out;598	}599 600	scan_time_ns = (end_time.tv_sec - start_time.tv_sec) * NSEC_PER_SEC +601		       (end_time.tv_nsec - start_time.tv_nsec);602 603	printf("Total size:    %lu MiB\n", map_size / MB);604	printf("Total time:    %ld.%09ld s\n", scan_time_ns / NSEC_PER_SEC,605	       scan_time_ns % NSEC_PER_SEC);606	printf("Average speed:  %.3f MiB/s\n", (map_size / MB) /607					       ((double)scan_time_ns / NSEC_PER_SEC));608 609	munmap(map_ptr_orig, len + HPAGE_SIZE);610	return KSFT_PASS;611 612err_out:613	printf("Not OK\n");614	munmap(map_ptr_orig, len + HPAGE_SIZE);615	return KSFT_FAIL;616}617 618static int ksm_merge_time(int merge_type, int mapping, int prot, int timeout, size_t map_size)619{620	void *map_ptr;621	struct timespec start_time, end_time;622	unsigned long scan_time_ns;623 624	map_size *= MB;625 626	map_ptr = allocate_memory(NULL, prot, mapping, '*', map_size);627	if (!map_ptr)628		return KSFT_FAIL;629 630	if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {631		perror("clock_gettime");632		goto err_out;633	}634	if (ksm_merge_pages(merge_type, map_ptr, map_size, start_time, timeout))635		goto err_out;636	if (clock_gettime(CLOCK_MONOTONIC_RAW, &end_time)) {637		perror("clock_gettime");638		goto err_out;639	}640 641	scan_time_ns = (end_time.tv_sec - start_time.tv_sec) * NSEC_PER_SEC +642		       (end_time.tv_nsec - start_time.tv_nsec);643 644	printf("Total size:    %lu MiB\n", map_size / MB);645	printf("Total time:    %ld.%09ld s\n", scan_time_ns / NSEC_PER_SEC,646	       scan_time_ns % NSEC_PER_SEC);647	printf("Average speed:  %.3f MiB/s\n", (map_size / MB) /648					       ((double)scan_time_ns / NSEC_PER_SEC));649 650	munmap(map_ptr, map_size);651	return KSFT_PASS;652 653err_out:654	printf("Not OK\n");655	munmap(map_ptr, map_size);656	return KSFT_FAIL;657}658 659static int ksm_unmerge_time(int merge_type, int mapping, int prot, int timeout, size_t map_size)660{661	void *map_ptr;662	struct timespec start_time, end_time;663	unsigned long scan_time_ns;664 665	map_size *= MB;666 667	map_ptr = allocate_memory(NULL, prot, mapping, '*', map_size);668	if (!map_ptr)669		return KSFT_FAIL;670	if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {671		perror("clock_gettime");672		goto err_out;673	}674	if (ksm_merge_pages(merge_type, map_ptr, map_size, start_time, timeout))675		goto err_out;676 677	if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {678		perror("clock_gettime");679		goto err_out;680	}681	if (ksm_unmerge_pages(map_ptr, map_size, start_time, timeout))682		goto err_out;683	if (clock_gettime(CLOCK_MONOTONIC_RAW, &end_time)) {684		perror("clock_gettime");685		goto err_out;686	}687 688	scan_time_ns = (end_time.tv_sec - start_time.tv_sec) * NSEC_PER_SEC +689		       (end_time.tv_nsec - start_time.tv_nsec);690 691	printf("Total size:    %lu MiB\n", map_size / MB);692	printf("Total time:    %ld.%09ld s\n", scan_time_ns / NSEC_PER_SEC,693	       scan_time_ns % NSEC_PER_SEC);694	printf("Average speed:  %.3f MiB/s\n", (map_size / MB) /695					       ((double)scan_time_ns / NSEC_PER_SEC));696 697	munmap(map_ptr, map_size);698	return KSFT_PASS;699 700err_out:701	printf("Not OK\n");702	munmap(map_ptr, map_size);703	return KSFT_FAIL;704}705 706static int ksm_cow_time(int merge_type, int mapping, int prot, int timeout, size_t page_size)707{708	void *map_ptr;709	struct timespec start_time, end_time;710	unsigned long cow_time_ns;711 712	/* page_count must be less than 2*page_size */713	size_t page_count = 4000;714 715	map_ptr = allocate_memory(NULL, prot, mapping, '*', page_size * page_count);716	if (!map_ptr)717		return KSFT_FAIL;718 719	if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {720		perror("clock_gettime");721		return KSFT_FAIL;722	}723	for (size_t i = 0; i < page_count - 1; i = i + 2)724		memset(map_ptr + page_size * i, '-', 1);725	if (clock_gettime(CLOCK_MONOTONIC_RAW, &end_time)) {726		perror("clock_gettime");727		return KSFT_FAIL;728	}729 730	cow_time_ns = (end_time.tv_sec - start_time.tv_sec) * NSEC_PER_SEC +731		       (end_time.tv_nsec - start_time.tv_nsec);732 733	printf("Total size:    %lu MiB\n\n", (page_size * page_count) / MB);734	printf("Not merged pages:\n");735	printf("Total time:     %ld.%09ld s\n", cow_time_ns / NSEC_PER_SEC,736	       cow_time_ns % NSEC_PER_SEC);737	printf("Average speed:  %.3f MiB/s\n\n", ((page_size * (page_count / 2)) / MB) /738					       ((double)cow_time_ns / NSEC_PER_SEC));739 740	/* Create 2000 pairs of duplicate pages */741	for (size_t i = 0; i < page_count - 1; i = i + 2) {742		memset(map_ptr + page_size * i, '+', i / 2 + 1);743		memset(map_ptr + page_size * (i + 1), '+', i / 2 + 1);744	}745	if (ksm_merge_pages(merge_type, map_ptr, page_size * page_count, start_time, timeout))746		goto err_out;747 748	if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {749		perror("clock_gettime");750		goto err_out;751	}752	for (size_t i = 0; i < page_count - 1; i = i + 2)753		memset(map_ptr + page_size * i, '-', 1);754	if (clock_gettime(CLOCK_MONOTONIC_RAW, &end_time)) {755		perror("clock_gettime");756		goto err_out;757	}758 759	cow_time_ns = (end_time.tv_sec - start_time.tv_sec) * NSEC_PER_SEC +760		       (end_time.tv_nsec - start_time.tv_nsec);761 762	printf("Merged pages:\n");763	printf("Total time:     %ld.%09ld s\n", cow_time_ns / NSEC_PER_SEC,764	       cow_time_ns % NSEC_PER_SEC);765	printf("Average speed:  %.3f MiB/s\n", ((page_size * (page_count / 2)) / MB) /766					       ((double)cow_time_ns / NSEC_PER_SEC));767 768	munmap(map_ptr, page_size * page_count);769	return KSFT_PASS;770 771err_out:772	printf("Not OK\n");773	munmap(map_ptr, page_size * page_count);774	return KSFT_FAIL;775}776 777int main(int argc, char *argv[])778{779	int ret, opt;780	int prot = 0;781	int ksm_scan_limit_sec = KSM_SCAN_LIMIT_SEC_DEFAULT;782	int merge_type = KSM_MERGE_TYPE_DEFAULT;783	long page_count = KSM_PAGE_COUNT_DEFAULT;784	size_t page_size = sysconf(_SC_PAGESIZE);785	struct ksm_sysfs ksm_sysfs_old;786	int test_name = CHECK_KSM_MERGE;787	bool use_zero_pages = KSM_USE_ZERO_PAGES_DEFAULT;788	bool merge_across_nodes = KSM_MERGE_ACROSS_NODES_DEFAULT;789	long size_MB = 0;790 791	while ((opt = getopt(argc, argv, "dha:p:l:z:m:s:t:MUZNPCHD")) != -1) {792		switch (opt) {793		case 'a':794			prot = str_to_prot(optarg);795			break;796		case 'p':797			page_count = atol(optarg);798			if (page_count <= 0) {799				printf("The number of pages must be greater than 0\n");800				return KSFT_FAIL;801			}802			break;803		case 'l':804			ksm_scan_limit_sec = atoi(optarg);805			if (ksm_scan_limit_sec <= 0) {806				printf("Timeout value must be greater than 0\n");807				return KSFT_FAIL;808			}809			break;810		case 'h':811			print_help();812			break;813		case 'z':814			if (strcmp(optarg, "0") == 0)815				use_zero_pages = 0;816			else817				use_zero_pages = 1;818			break;819		case 'm':820			if (strcmp(optarg, "0") == 0)821				merge_across_nodes = 0;822			else823				merge_across_nodes = 1;824			break;825		case 'd':826			debug = 1;827			break;828		case 's':829			size_MB = atoi(optarg);830			if (size_MB <= 0) {831				printf("Size must be greater than 0\n");832				return KSFT_FAIL;833			}834			break;835		case 't':836			{837				int tmp = atoi(optarg);838 839				if (tmp < 0 || tmp > KSM_MERGE_LAST) {840					printf("Invalid merge type\n");841					return KSFT_FAIL;842				}843				merge_type = tmp;844			}845			break;846		case 'M':847			break;848		case 'U':849			test_name = CHECK_KSM_UNMERGE;850			break;851		case 'Z':852			test_name = CHECK_KSM_ZERO_PAGE_MERGE;853			break;854		case 'N':855			test_name = CHECK_KSM_NUMA_MERGE;856			break;857		case 'P':858			test_name = KSM_MERGE_TIME;859			break;860		case 'H':861			test_name = KSM_MERGE_TIME_HUGE_PAGES;862			break;863		case 'D':864			test_name = KSM_UNMERGE_TIME;865			break;866		case 'C':867			test_name = KSM_COW_TIME;868			break;869		default:870			return KSFT_FAIL;871		}872	}873 874	if (prot == 0)875		prot = str_to_prot(KSM_PROT_STR_DEFAULT);876 877	if (access(KSM_SYSFS_PATH, F_OK)) {878		printf("Config KSM not enabled\n");879		return KSFT_SKIP;880	}881 882	if (ksm_save_def(&ksm_sysfs_old)) {883		printf("Cannot save default tunables\n");884		return KSFT_FAIL;885	}886 887	if (ksm_write_sysfs(KSM_FP("run"), 2) ||888	    ksm_write_sysfs(KSM_FP("sleep_millisecs"), 0) ||889	    numa_available() ? 0 :890		ksm_write_sysfs(KSM_FP("merge_across_nodes"), 1) ||891	    ksm_write_sysfs(KSM_FP("pages_to_scan"), page_count))892		return KSFT_FAIL;893 894	switch (test_name) {895	case CHECK_KSM_MERGE:896		ret = check_ksm_merge(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot, page_count,897				      ksm_scan_limit_sec, page_size);898		break;899	case CHECK_KSM_UNMERGE:900		ret = check_ksm_unmerge(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot,901					ksm_scan_limit_sec, page_size);902		break;903	case CHECK_KSM_ZERO_PAGE_MERGE:904		ret = check_ksm_zero_page_merge(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot,905						page_count, ksm_scan_limit_sec, use_zero_pages,906						page_size);907		break;908	case CHECK_KSM_NUMA_MERGE:909		ret = check_ksm_numa_merge(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot,910					ksm_scan_limit_sec, merge_across_nodes, page_size);911		break;912	case KSM_MERGE_TIME:913		if (size_MB == 0) {914			printf("Option '-s' is required.\n");915			return KSFT_FAIL;916		}917		ret = ksm_merge_time(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot,918				ksm_scan_limit_sec, size_MB);919		break;920	case KSM_MERGE_TIME_HUGE_PAGES:921		if (size_MB == 0) {922			printf("Option '-s' is required.\n");923			return KSFT_FAIL;924		}925		ret = ksm_merge_hugepages_time(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot,926				ksm_scan_limit_sec, size_MB);927		break;928	case KSM_UNMERGE_TIME:929		if (size_MB == 0) {930			printf("Option '-s' is required.\n");931			return KSFT_FAIL;932		}933		ret = ksm_unmerge_time(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot,934				       ksm_scan_limit_sec, size_MB);935		break;936	case KSM_COW_TIME:937		ret = ksm_cow_time(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot,938				ksm_scan_limit_sec, page_size);939		break;940	}941 942	if (ksm_restore(&ksm_sysfs_old)) {943		printf("Cannot restore default tunables\n");944		return KSFT_FAIL;945	}946 947	return ret;948}949