tools/testing/selftests/vm/gup_test.c

   1 #include <fcntl.h>
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #include <unistd.h>
   5 #include <sys/ioctl.h>
   6 #include <sys/mman.h>
   7 #include <sys/stat.h>
   8 #include <sys/types.h>
   9 #include "../../../../mm/gup_test.h"
  10
  11 #define MB (1UL << 20)
  12 #define PAGE_SIZE sysconf(_SC_PAGESIZE)
  13
  14 /* Just the flags we need, copied from mm.h: */
  15 #define FOLL_WRITE      0x01    /* check pte is writable */
  16 #define FOLL_TOUCH      0x02    /* mark page accessed */
  17
  18 static char *cmd_to_str(unsigned long cmd)
  19 {
  20         switch (cmd) {
  21         case GUP_FAST_BENCHMARK:
  22                 return "GUP_FAST_BENCHMARK";
  23         case PIN_FAST_BENCHMARK:
  24                 return "PIN_FAST_BENCHMARK";
  25         case PIN_LONGTERM_BENCHMARK:
  26                 return "PIN_LONGTERM_BENCHMARK";
  27         case GUP_BASIC_TEST:
  28                 return "GUP_BASIC_TEST";
  29         case PIN_BASIC_TEST:
  30                 return "PIN_BASIC_TEST";
  31         case DUMP_USER_PAGES_TEST:
  32                 return "DUMP_USER_PAGES_TEST";
  33         }
  34         return "Unknown command";
  35 }
  36
  37 int main(int argc, char **argv)
  38 {
  39         struct gup_test gup = { 0 };
  40         unsigned long size = 128 * MB;
  41         int i, fd, filed, opt, nr_pages = 1, thp = -1, repeats = 1, write = 1;
  42         unsigned long cmd = GUP_FAST_BENCHMARK;
  43         int flags = MAP_PRIVATE, touch = 0;
  44         char *file = "/dev/zero";
  45         char *p;
  46
  47         while ((opt = getopt(argc, argv, "m:r:n:F:f:abctTLUuwWSHpz")) != -1) {
  48                 switch (opt) {
  49                 case 'a':
  50                         cmd = PIN_FAST_BENCHMARK;
  51                         break;
  52                 case 'b':
  53                         cmd = PIN_BASIC_TEST;
  54                         break;
  55                 case 'L':
  56                         cmd = PIN_LONGTERM_BENCHMARK;
  57                         break;
  58                 case 'c':
  59                         cmd = DUMP_USER_PAGES_TEST;
  60                         /*
  61                          * Dump page 0 (index 1). May be overridden later, by
  62                          * user's non-option arguments.
  63                          *
  64                          * .which_pages is zero-based, so that zero can mean "do
  65                          * nothing".
  66                          */
  67                         gup.which_pages[0] = 1;
  68                         break;
  69                 case 'p':
  70                         /* works only with DUMP_USER_PAGES_TEST */
  71                         gup.test_flags |= GUP_TEST_FLAG_DUMP_PAGES_USE_PIN;
  72                         break;
  73                 case 'F':
  74                         /* strtol, so you can pass flags in hex form */
  75                         gup.gup_flags = strtol(optarg, 0, 0);
  76                         break;
  77                 case 'm':
  78                         size = atoi(optarg) * MB;
  79                         break;
  80                 case 'r':
  81                         repeats = atoi(optarg);
  82                         break;
  83                 case 'n':
  84                         nr_pages = atoi(optarg);
  85                         break;
  86                 case 't':
  87                         thp = 1;
  88                         break;
  89                 case 'T':
  90                         thp = 0;
  91                         break;
  92                 case 'U':
  93                         cmd = GUP_BASIC_TEST;
  94                         break;
  95                 case 'u':
  96                         cmd = GUP_FAST_BENCHMARK;
  97                         break;
  98                 case 'w':
  99                         write = 1;
 100                         break;
 101                 case 'W':
 102                         write = 0;
 103                         break;
 104                 case 'f':
 105                         file = optarg;
 106                         break;
 107                 case 'S':
 108                         flags &= ~MAP_PRIVATE;
 109                         flags |= MAP_SHARED;
 110                         break;
 111                 case 'H':
 112                         flags |= (MAP_HUGETLB | MAP_ANONYMOUS);
 113                         break;
 114                 case 'z':
 115                         /* fault pages in gup, do not fault in userland */
 116                         touch = 1;
 117                         break;
 118                 default:
 119                         return -1;
 120                 }
 121         }
 122
 123         if (optind < argc) {
 124                 int extra_arg_count = 0;
 125                 /*
 126                  * For example:
 127                  *
 128                  *   ./gup_test -c 0 1 0x1001
 129                  *
 130                  * ...to dump pages 0, 1, and 4097
 131                  */
 132
 133                 while ((optind < argc) &&
 134                        (extra_arg_count < GUP_TEST_MAX_PAGES_TO_DUMP)) {
 135                         /*
 136                          * Do the 1-based indexing here, so that the user can
 137                          * use normal 0-based indexing on the command line.
 138                          */
 139                         long page_index = strtol(argv[optind], 0, 0) + 1;
 140
 141                         gup.which_pages[extra_arg_count] = page_index;
 142                         extra_arg_count++;
 143                         optind++;
 144                 }
 145         }
 146
 147         filed = open(file, O_RDWR|O_CREAT);
 148         if (filed < 0) {
 149                 perror("open");
 150                 exit(filed);
 151         }
 152
 153         gup.nr_pages_per_call = nr_pages;
 154         if (write)
 155                 gup.gup_flags |= FOLL_WRITE;
 156
 157         fd = open("/sys/kernel/debug/gup_test", O_RDWR);
 158         if (fd == -1) {
 159                 perror("open");
 160                 exit(1);
 161         }
 162
 163         p = mmap(NULL, size, PROT_READ | PROT_WRITE, flags, filed, 0);
 164         if (p == MAP_FAILED) {
 165                 perror("mmap");
 166                 exit(1);
 167         }
 168         gup.addr = (unsigned long)p;
 169
 170         if (thp == 1)
 171                 madvise(p, size, MADV_HUGEPAGE);
 172         else if (thp == 0)
 173                 madvise(p, size, MADV_NOHUGEPAGE);
 174
 175         /*
 176          * FOLL_TOUCH, in gup_test, is used as an either/or case: either
 177          * fault pages in from the kernel via FOLL_TOUCH, or fault them
 178          * in here, from user space. This allows comparison of performance
 179          * between those two cases.
 180          */
 181         if (touch) {
 182                 gup.gup_flags |= FOLL_TOUCH;
 183         } else {
 184                 for (; (unsigned long)p < gup.addr + size; p += PAGE_SIZE)
 185                         p[0] = 0;
 186         }
 187
 188         /* Only report timing information on the *_BENCHMARK commands: */
 189         if ((cmd == PIN_FAST_BENCHMARK) || (cmd == GUP_FAST_BENCHMARK) ||
 190              (cmd == PIN_LONGTERM_BENCHMARK)) {
 191                 for (i = 0; i < repeats; i++) {
 192                         gup.size = size;
 193                         if (ioctl(fd, cmd, &gup))
 194                                 perror("ioctl"), exit(1);
 195
 196                         printf("%s: Time: get:%lld put:%lld us",
 197                                cmd_to_str(cmd), gup.get_delta_usec,
 198                                gup.put_delta_usec);
 199                         if (gup.size != size)
 200                                 printf(", truncated (size: %lld)", gup.size);
 201                         printf("\n");
 202                 }
 203         } else {
 204                 gup.size = size;
 205                 if (ioctl(fd, cmd, &gup)) {
 206                         perror("ioctl");
 207                         exit(1);
 208                 }
 209
 210                 printf("%s: done\n", cmd_to_str(cmd));
 211                 if (gup.size != size)
 212                         printf("Truncated (size: %lld)\n", gup.size);
 213         }
 214
 215         return 0;
 216 }