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, filed, opt, nr_pages = 1, thp = -1, repeats = 1, write = 0;
  35         int cmd = GUP_FAST_BENCHMARK, flags = MAP_PRIVATE;
  36         char *file = "/dev/zero";
  37         char *p;
  38
  39         while ((opt = getopt(argc, argv, "m:r:n:f:tTLUSH")) != -1) {
  40                 switch (opt) {
  41                 case 'm':
  42                         size = atoi(optarg) * MB;
  43                         break;
  44                 case 'r':
  45                         repeats = atoi(optarg);
  46                         break;
  47                 case 'n':
  48                         nr_pages = atoi(optarg);
  49                         break;
  50                 case 't':
  51                         thp = 1;
  52                         break;
  53                 case 'T':
  54                         thp = 0;
  55                         break;
  56                 case 'L':
  57                         cmd = GUP_LONGTERM_BENCHMARK;
  58                         break;
  59                 case 'U':
  60                         cmd = GUP_BENCHMARK;
  61                         break;
  62                 case 'w':
  63                         write = 1;
  64                         break;
  65                 case 'f':
  66                         file = optarg;
  67                         break;
  68                 case 'S':
  69                         flags &= ~MAP_PRIVATE;
  70                         flags |= MAP_SHARED;
  71                         break;
  72                 case 'H':
  73                         flags |= MAP_HUGETLB;
  74                         break;
  75                 default:
  76                         return -1;
  77                 }
  78         }
  79
  80         filed = open(file, O_RDWR|O_CREAT);
  81         if (filed < 0) {
  82                 perror("open");
  83                 exit(filed);
  84         }
  85
  86         gup.nr_pages_per_call = nr_pages;
  87         gup.flags = write;
  88
  89         fd = open("/sys/kernel/debug/gup_benchmark", O_RDWR);
  90         if (fd == -1)
  91                 perror("open"), exit(1);
  92
  93         p = mmap(NULL, size, PROT_READ | PROT_WRITE, flags, filed, 0);
  94         if (p == MAP_FAILED)
  95                 perror("mmap"), exit(1);
  96         gup.addr = (unsigned long)p;
  97
  98         if (thp == 1)
  99                 madvise(p, size, MADV_HUGEPAGE);
 100         else if (thp == 0)
 101                 madvise(p, size, MADV_NOHUGEPAGE);
 102
 103         for (; (unsigned long)p < gup.addr + size; p += PAGE_SIZE)
 104                 p[0] = 0;
 105
 106         for (i = 0; i < repeats; i++) {
 107                 gup.size = size;
 108                 if (ioctl(fd, cmd, &gup))
 109                         perror("ioctl"), exit(1);
 110
 111                 printf("Time: get:%lld put:%lld us", gup.get_delta_usec,
 112                         gup.put_delta_usec);
 113                 if (gup.size != size)
 114                         printf(", truncated (size: %lld)", gup.size);
 115                 printf("\n");
 116         }
 117
 118         return 0;
 119 }