xref: /linux/tools/testing/selftests/mm/transhuge-stress.c (revision 40d269c000bda9fcd276a0412a9cebd3f6e344c5)
1 /*
2  * Stress test for transparent huge pages, memory compaction and migration.
3  *
4  * Authors: Konstantin Khlebnikov <koct9i@gmail.com>
5  *
6  * This is free and unencumbered software released into the public domain.
7  */
8 
9 #include <stdlib.h>
10 #include <stdio.h>
11 #include <stdint.h>
12 #include <err.h>
13 #include <time.h>
14 #include <unistd.h>
15 #include <fcntl.h>
16 #include <string.h>
17 #include <sys/mman.h>
18 #include "vm_util.h"
19 #include "../kselftest.h"
20 
21 int backing_fd = -1;
22 int mmap_flags = MAP_ANONYMOUS | MAP_NORESERVE | MAP_PRIVATE;
23 #define PROT_RW (PROT_READ | PROT_WRITE)
24 
25 int main(int argc, char **argv)
26 {
27 	size_t ram, len;
28 	void *ptr, *p;
29 	struct timespec start, a, b;
30 	int i = 0;
31 	char *name = NULL;
32 	double s;
33 	uint8_t *map;
34 	size_t map_len;
35 	int pagemap_fd;
36 	int duration = 0;
37 
38 	ksft_print_header();
39 
40 	ram = sysconf(_SC_PHYS_PAGES);
41 	if (ram > SIZE_MAX / psize() / 4)
42 		ram = SIZE_MAX / 4;
43 	else
44 		ram *= psize();
45 	len = ram;
46 
47 	while (++i < argc) {
48 		if (!strcmp(argv[i], "-h"))
49 			ksft_exit_fail_msg("usage: %s [-f <filename>] [-d <duration>] [size in MiB]\n",
50 					   argv[0]);
51 		else if (!strcmp(argv[i], "-f"))
52 			name = argv[++i];
53 		else if (!strcmp(argv[i], "-d"))
54 			duration = atoi(argv[++i]);
55 		else
56 			len = atoll(argv[i]) << 20;
57 	}
58 
59 	ksft_set_plan(1);
60 
61 	if (name) {
62 		backing_fd = open(name, O_RDWR);
63 		if (backing_fd == -1)
64 			ksft_exit_fail_msg("open %s\n", name);
65 		mmap_flags = MAP_SHARED;
66 	}
67 
68 	warnx("allocate %zd transhuge pages, using %zd MiB virtual memory"
69 	      " and %zd MiB of ram", len >> HPAGE_SHIFT, len >> 20,
70 	      ram >> (20 + HPAGE_SHIFT - pshift() - 1));
71 
72 	pagemap_fd = open("/proc/self/pagemap", O_RDONLY);
73 	if (pagemap_fd < 0)
74 		ksft_exit_fail_msg("open pagemap\n");
75 
76 	len -= len % HPAGE_SIZE;
77 	ptr = mmap(NULL, len + HPAGE_SIZE, PROT_RW, mmap_flags, backing_fd, 0);
78 	if (ptr == MAP_FAILED)
79 		ksft_exit_fail_msg("initial mmap");
80 	ptr += HPAGE_SIZE - (uintptr_t)ptr % HPAGE_SIZE;
81 
82 	if (madvise(ptr, len, MADV_HUGEPAGE))
83 		ksft_exit_fail_msg("MADV_HUGEPAGE");
84 
85 	map_len = ram >> (HPAGE_SHIFT - 1);
86 	map = malloc(map_len);
87 	if (!map)
88 		ksft_exit_fail_msg("map malloc\n");
89 
90 	clock_gettime(CLOCK_MONOTONIC, &start);
91 
92 	while (1) {
93 		int nr_succeed = 0, nr_failed = 0, nr_pages = 0;
94 
95 		memset(map, 0, map_len);
96 
97 		clock_gettime(CLOCK_MONOTONIC, &a);
98 		for (p = ptr; p < ptr + len; p += HPAGE_SIZE) {
99 			int64_t pfn;
100 
101 			pfn = allocate_transhuge(p, pagemap_fd);
102 
103 			if (pfn < 0) {
104 				nr_failed++;
105 			} else {
106 				size_t idx = pfn >> (HPAGE_SHIFT - pshift());
107 
108 				nr_succeed++;
109 				if (idx >= map_len) {
110 					map = realloc(map, idx + 1);
111 					if (!map)
112 						ksft_exit_fail_msg("map realloc\n");
113 					memset(map + map_len, 0, idx + 1 - map_len);
114 					map_len = idx + 1;
115 				}
116 				if (!map[idx])
117 					nr_pages++;
118 				map[idx] = 1;
119 			}
120 
121 			/* split transhuge page, keep last page */
122 			if (madvise(p, HPAGE_SIZE - psize(), MADV_DONTNEED))
123 				ksft_exit_fail_msg("MADV_DONTNEED");
124 		}
125 		clock_gettime(CLOCK_MONOTONIC, &b);
126 		s = b.tv_sec - a.tv_sec + (b.tv_nsec - a.tv_nsec) / 1000000000.;
127 
128 		ksft_print_msg("%.3f s/loop, %.3f ms/page, %10.3f MiB/s\t"
129 			       "%4d succeed, %4d failed, %4d different pages\n",
130 			       s, s * 1000 / (len >> HPAGE_SHIFT), len / s / (1 << 20),
131 			       nr_succeed, nr_failed, nr_pages);
132 
133 		if (duration > 0 && b.tv_sec - start.tv_sec >= duration) {
134 			ksft_test_result_pass("Completed\n");
135 			ksft_finished();
136 		}
137 	}
138 }
139