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         __u64 expansion[10];    /* For future use */
  29 };
  30
  31 int main(int argc, char **argv)
  32 {
  33         struct gup_benchmark gup;
  34         unsigned long size = 128 * MB;
  35         int i, fd, filed, opt, nr_pages = 1, thp = -1, repeats = 1, write = 0;
  36         int cmd = GUP_FAST_BENCHMARK, flags = MAP_PRIVATE;
  37         char *file = "/dev/zero";
  38         char *p;
  39
  40         while ((opt = getopt(argc, argv, "m:r:n:f:tTLUSH")) != -1) {
  41                 switch (opt) {
  42                 case 'm':
  43                         size = atoi(optarg) * MB;
  44                         break;
  45                 case 'r':
  46                         repeats = atoi(optarg);
  47                         break;
  48                 case 'n':
  49                         nr_pages = atoi(optarg);
  50                         break;
  51                 case 't':
  52                         thp = 1;
  53                         break;
  54                 case 'T':
  55                         thp = 0;
  56                         break;
  57                 case 'L':
  58                         cmd = GUP_LONGTERM_BENCHMARK;
  59                         break;
  60                 case 'U':
  61                         cmd = GUP_BENCHMARK;
  62                         break;
  63                 case 'w':
  64                         write = 1;
  65                         break;
  66                 case 'f':
  67                         file = optarg;
  68                         break;
  69                 case 'S':
  70                         flags &= ~MAP_PRIVATE;
  71                         flags |= MAP_SHARED;
  72                         break;
  73                 case 'H':
  74                         flags |= MAP_HUGETLB;
  75                         break;
  76                 default:
  77                         return -1;
  78                 }
  79         }
  80
  81         filed = open(file, O_RDWR|O_CREAT);
  82         if (filed < 0) {
  83                 perror("open");
  84                 exit(filed);
  85         }
  86
  87         gup.nr_pages_per_call = nr_pages;
  88         gup.flags = write;
  89
  90         fd = open("/sys/kernel/debug/gup_benchmark", O_RDWR);
  91         if (fd == -1)
  92                 perror("open"), exit(1);
  93
  94         p = mmap(NULL, size, PROT_READ | PROT_WRITE, flags, filed, 0);
  95         if (p == MAP_FAILED)
  96                 perror("mmap"), exit(1);
  97         gup.addr = (unsigned long)p;
  98
  99         if (thp == 1)
 100                 madvise(p, size, MADV_HUGEPAGE);
 101         else if (thp == 0)
 102                 madvise(p, size, MADV_NOHUGEPAGE);
 103
 104         for (; (unsigned long)p < gup.addr + size; p += PAGE_SIZE)
 105                 p[0] = 0;
 106
 107         for (i = 0; i < repeats; i++) {
 108                 gup.size = size;
 109                 if (ioctl(fd, cmd, &gup))
 110                         perror("ioctl"), exit(1);
 111
 112                 printf("Time: get:%lld put:%lld us", gup.get_delta_usec,
 113                         gup.put_delta_usec);
 114                 if (gup.size != size)
 115                         printf(", truncated (size: %lld)", gup.size);
 116                 printf("\n");
 117         }
 118
 119         return 0;
 120 }