tools/testing/selftests/mm/transhuge-stress.c

   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 }