tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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#include "thp_settings.h"
21
22int backing_fd = -1;
23int mmap_flags = MAP_ANONYMOUS | MAP_NORESERVE | MAP_PRIVATE;
24#define PROT_RW (PROT_READ | PROT_WRITE)
25
26int main(int argc, char **argv)
27{
28 size_t ram, len;
29 void *ptr, *p;
30 struct timespec start, a, b;
31 int i = 0;
32 char *name = NULL;
33 double s;
34 uint8_t *map;
35 size_t map_len;
36 int pagemap_fd;
37 int duration = 0;
38
39 ksft_print_header();
40
41 if (!thp_is_enabled())
42 ksft_exit_skip("Transparent Hugepages not available\n");
43
44 ram = sysconf(_SC_PHYS_PAGES);
45 if (ram > SIZE_MAX / psize() / 4)
46 ram = SIZE_MAX / 4;
47 else
48 ram *= psize();
49 len = ram;
50
51 while (++i < argc) {
52 if (!strcmp(argv[i], "-h"))
53 ksft_exit_fail_msg("usage: %s [-f <filename>] [-d <duration>] [size in MiB]\n",
54 argv[0]);
55 else if (!strcmp(argv[i], "-f"))
56 name = argv[++i];
57 else if (!strcmp(argv[i], "-d"))
58 duration = atoi(argv[++i]);
59 else
60 len = atoll(argv[i]) << 20;
61 }
62
63 ksft_set_plan(1);
64
65 if (name) {
66 backing_fd = open(name, O_RDWR);
67 if (backing_fd == -1)
68 ksft_exit_fail_msg("open %s\n", name);
69 mmap_flags = MAP_SHARED;
70 }
71
72 warnx("allocate %zd transhuge pages, using %zd MiB virtual memory"
73 " and %zd MiB of ram", len >> HPAGE_SHIFT, len >> 20,
74 ram >> (20 + HPAGE_SHIFT - pshift() - 1));
75
76 pagemap_fd = open("/proc/self/pagemap", O_RDONLY);
77 if (pagemap_fd < 0)
78 ksft_exit_fail_msg("open pagemap\n");
79
80 len -= len % HPAGE_SIZE;
81 ptr = mmap(NULL, len + HPAGE_SIZE, PROT_RW, mmap_flags, backing_fd, 0);
82 if (ptr == MAP_FAILED)
83 ksft_exit_fail_msg("initial mmap");
84 ptr += HPAGE_SIZE - (uintptr_t)ptr % HPAGE_SIZE;
85
86 if (madvise(ptr, len, MADV_HUGEPAGE))
87 ksft_exit_fail_msg("MADV_HUGEPAGE");
88
89 map_len = ram >> (HPAGE_SHIFT - 1);
90 map = malloc(map_len);
91 if (!map)
92 ksft_exit_fail_msg("map malloc\n");
93
94 clock_gettime(CLOCK_MONOTONIC, &start);
95
96 while (1) {
97 int nr_succeed = 0, nr_failed = 0, nr_pages = 0;
98
99 memset(map, 0, map_len);
100
101 clock_gettime(CLOCK_MONOTONIC, &a);
102 for (p = ptr; p < ptr + len; p += HPAGE_SIZE) {
103 int64_t pfn;
104
105 pfn = allocate_transhuge(p, pagemap_fd);
106
107 if (pfn < 0) {
108 nr_failed++;
109 } else {
110 size_t idx = pfn >> (HPAGE_SHIFT - pshift());
111
112 nr_succeed++;
113 if (idx >= map_len) {
114 map = realloc(map, idx + 1);
115 if (!map)
116 ksft_exit_fail_msg("map realloc\n");
117 memset(map + map_len, 0, idx + 1 - map_len);
118 map_len = idx + 1;
119 }
120 if (!map[idx])
121 nr_pages++;
122 map[idx] = 1;
123 }
124
125 /* split transhuge page, keep last page */
126 if (madvise(p, HPAGE_SIZE - psize(), MADV_DONTNEED))
127 ksft_exit_fail_msg("MADV_DONTNEED");
128 }
129 clock_gettime(CLOCK_MONOTONIC, &b);
130 s = b.tv_sec - a.tv_sec + (b.tv_nsec - a.tv_nsec) / 1000000000.;
131
132 ksft_print_msg("%.3f s/loop, %.3f ms/page, %10.3f MiB/s\t"
133 "%4d succeed, %4d failed, %4d different pages\n",
134 s, s * 1000 / (len >> HPAGE_SHIFT), len / s / (1 << 20),
135 nr_succeed, nr_failed, nr_pages);
136
137 if (duration > 0 && b.tv_sec - start.tv_sec >= duration) {
138 ksft_test_result_pass("Completed\n");
139 ksft_finished();
140 }
141 }
142}