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 struct gup_benchmark {
  22         __u64 get_delta_usec;
  23         __u64 put_delta_usec;
  24         __u64 addr;
  25         __u64 size;
  26         __u32 nr_pages_per_call;
  27         __u32 flags;
  28 };
  29
  30 int main(int argc, char **argv)
  31 {
  32         struct gup_benchmark gup;
  33         unsigned long size = 128 * MB;
  34         int i, fd, opt, nr_pages = 1, thp = -1, repeats = 1, write = 0;
  35         int cmd = GUP_FAST_BENCHMARK;
  36         char *p;
  37
  38         while ((opt = getopt(argc, argv, "m:r:n:tTLU")) != -1) {
  39                 switch (opt) {
  40                 case 'm':
  41                         size = atoi(optarg) * MB;
  42                         break;
  43                 case 'r':
  44                         repeats = atoi(optarg);
  45                         break;
  46                 case 'n':
  47                         nr_pages = atoi(optarg);
  48                         break;
  49                 case 't':
  50                         thp = 1;
  51                         break;
  52                 case 'T':
  53                         thp = 0;
  54                         break;
  55                 case 'L':
  56                         cmd = GUP_LONGTERM_BENCHMARK;
  57                         break;
  58                 case 'U':
  59                         cmd = GUP_BENCHMARK;
  60                         break;
  61                 case 'w':
  62                         write = 1;
  63                 default:
  64                         return -1;
  65                 }
  66         }
  67
  68         gup.nr_pages_per_call = nr_pages;
  69         gup.flags = write;
  70
  71         fd = open("/sys/kernel/debug/gup_benchmark", O_RDWR);
  72         if (fd == -1)
  73                 perror("open"), exit(1);
  74
  75         p = mmap(NULL, size, PROT_READ | PROT_WRITE,
  76                         MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
  77         if (p == MAP_FAILED)
  78                 perror("mmap"), exit(1);
  79         gup.addr = (unsigned long)p;
  80
  81         if (thp == 1)
  82                 madvise(p, size, MADV_HUGEPAGE);
  83         else if (thp == 0)
  84                 madvise(p, size, MADV_NOHUGEPAGE);
  85
  86         for (; (unsigned long)p < gup.addr + size; p += PAGE_SIZE)
  87                 p[0] = 0;
  88
  89         for (i = 0; i < repeats; i++) {
  90                 gup.size = size;
  91                 if (ioctl(fd, cmd, &gup))
  92                         perror("ioctl"), exit(1);
  93
  94                 printf("Time: get:%lld put:%lld us", gup.get_delta_usec,
  95                         gup.put_delta_usec);
  96                 if (gup.size != size)
  97                         printf(", truncated (size: %lld)", gup.size);
  98                 printf("\n");
  99         }
 100
 101         return 0;
 102 }