tools/testing/selftests/vm/gup_benchmark.c

   1 #include <fcntl.h>
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #include <unistd.h>
   5
   6 #include <sys/ioctl.h>
   7 #include <sys/mman.h>
   8 #include <sys/prctl.h>
   9 #include <sys/stat.h>
  10 #include <sys/types.h>
  11
  12 #include <linux/types.h>
  13
  14 #define MB (1UL << 20)
  15 #define PAGE_SIZE sysconf(_SC_PAGESIZE)
  16
  17 #define GUP_FAST_BENCHMARK      _IOWR('g', 1, struct gup_benchmark)
  18 #define GUP_LONGTERM_BENCHMARK  _IOWR('g', 2, struct gup_benchmark)
  19 #define GUP_BENCHMARK           _IOWR('g', 3, struct gup_benchmark)
  20
  21 /* Just the flags we need, copied from mm.h: */
  22 #define FOLL_WRITE      0x01    /* check pte is writable */
  23
  24 struct gup_benchmark {
  25         __u64 get_delta_usec;
  26         __u64 put_delta_usec;
  27         __u64 addr;
  28         __u64 size;
  29         __u32 nr_pages_per_call;
  30         __u32 flags;
  31         __u64 expansion[10];    /* For future use */
  32 };
  33
  34 int main(int argc, char **argv)
  35 {
  36         struct gup_benchmark gup;
  37         unsigned long size = 128 * MB;
  38         int i, fd, filed, opt, nr_pages = 1, thp = -1, repeats = 1, write = 0;
  39         int cmd = GUP_FAST_BENCHMARK, flags = MAP_PRIVATE;
  40         char *file = "/dev/zero";
  41         char *p;
  42
  43         while ((opt = getopt(argc, argv, "m:r:n:f:tTLUwSH")) != -1) {
  44                 switch (opt) {
  45                 case 'm':
  46                         size = atoi(optarg) * MB;
  47                         break;
  48                 case 'r':
  49                         repeats = atoi(optarg);
  50                         break;
  51                 case 'n':
  52                         nr_pages = atoi(optarg);
  53                         break;
  54                 case 't':
  55                         thp = 1;
  56                         break;
  57                 case 'T':
  58                         thp = 0;
  59                         break;
  60                 case 'L':
  61                         cmd = GUP_LONGTERM_BENCHMARK;
  62                         break;
  63                 case 'U':
  64                         cmd = GUP_BENCHMARK;
  65                         break;
  66                 case 'w':
  67                         write = 1;
  68                         break;
  69                 case 'f':
  70                         file = optarg;
  71                         break;
  72                 case 'S':
  73                         flags &= ~MAP_PRIVATE;
  74                         flags |= MAP_SHARED;
  75                         break;
  76                 case 'H':
  77                         flags |= (MAP_HUGETLB | MAP_ANONYMOUS);
  78                         break;
  79                 default:
  80                         return -1;
  81                 }
  82         }
  83
  84         filed = open(file, O_RDWR|O_CREAT);
  85         if (filed < 0) {
  86                 perror("open");
  87                 exit(filed);
  88         }
  89
  90         gup.nr_pages_per_call = nr_pages;
  91         if (write)
  92                 gup.flags |= FOLL_WRITE;
  93
  94         fd = open("/sys/kernel/debug/gup_benchmark", O_RDWR);
  95         if (fd == -1)
  96                 perror("open"), exit(1);
  97
  98         p = mmap(NULL, size, PROT_READ | PROT_WRITE, flags, filed, 0);
  99         if (p == MAP_FAILED)
 100                 perror("mmap"), exit(1);
 101         gup.addr = (unsigned long)p;
 102
 103         if (thp == 1)
 104                 madvise(p, size, MADV_HUGEPAGE);
 105         else if (thp == 0)
 106                 madvise(p, size, MADV_NOHUGEPAGE);
 107
 108         for (; (unsigned long)p < gup.addr + size; p += PAGE_SIZE)
 109                 p[0] = 0;
 110
 111         for (i = 0; i < repeats; i++) {
 112                 gup.size = size;
 113                 if (ioctl(fd, cmd, &gup))
 114                         perror("ioctl"), exit(1);
 115
 116                 printf("Time: get:%lld put:%lld us", gup.get_delta_usec,
 117                         gup.put_delta_usec);
 118                 if (gup.size != size)
 119                         printf(", truncated (size: %lld)", gup.size);
 120                 printf("\n");
 121         }
 122
 123         return 0;
 124 }