tools/tests/perf_index/test_fault_helper.c

   1 #include "test_fault_helper.h"
   2 #include "fail.h"
   3 #include <sys/mman.h>
   4 #include <stdlib.h>
   5 #include <unistd.h>
   6 #include <assert.h>
   7 #include <TargetConditionals.h>
   8
   9 #if TARGET_OS_EMBEDDED
  10 #define MEMSIZE (1L<<28)
  11 #else
  12 #define MEMSIZE (1L<<30)
  13 #endif
  14
  15 static char* memblock;
  16
  17 int test_fault_setup() {
  18     char *ptr;
  19     int pgsz = getpagesize();
  20     int retval;
  21
  22     memblock = (char *)mmap(NULL, MEMSIZE, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0);
  23     VERIFY(memblock != MAP_FAILED, "mmap failed");
  24
  25     /* make sure memory is paged */
  26     for(ptr = memblock; ptr<memblock+MEMSIZE; ptr+= pgsz) {
  27         *ptr = 1;
  28     }
  29
  30     /* set to read only, then back to read write so it faults on first write */
  31     retval = mprotect(memblock, MEMSIZE, PROT_READ);
  32     VERIFY(retval == 0, "mprotect failed");
  33
  34     retval = mprotect(memblock, MEMSIZE, PROT_READ | PROT_WRITE);
  35     VERIFY(retval == 0, "mprotect failed");
  36
  37     return PERFINDEX_SUCCESS;
  38 }
  39
  40 int test_fault_helper(int thread_id, int num_threads, long long length, testtype_t testtype) {
  41     char *ptr;
  42     int pgsz = getpagesize();
  43     int retval;
  44
  45     long long num_pages = MEMSIZE / pgsz;
  46     long long region_len = num_pages/num_threads;
  47     long long region_start = region_len * thread_id;
  48     long long region_end;
  49
  50     if(thread_id < num_pages % num_threads) {
  51         region_start += thread_id;
  52         region_len++;
  53     }
  54     else {
  55         region_start += num_pages % num_threads;
  56     }
  57
  58     region_start *= pgsz;
  59     region_len *= pgsz;
  60     region_end = region_start + region_len;
  61
  62     long long left = length;
  63
  64     while(1) {
  65         for(ptr = memblock+region_start; ptr<memblock+region_end; ptr+= pgsz) {
  66             *ptr = 1;
  67             left--;
  68             if(left==0)
  69                 break;
  70         }
  71
  72         if(left==0)
  73             break;
  74
  75         if(testtype == TESTFAULT) {
  76             retval = mprotect(memblock+region_start, region_len, PROT_READ) == 0;
  77             VERIFY(retval == 0, "mprotect failed");
  78             retval = mprotect(memblock+region_start, region_len, PROT_READ | PROT_WRITE) == 0;
  79             VERIFY(retval == 0, "mprotect failed");
  80         }
  81
  82         else if(testtype == TESTZFOD) {
  83             retval = munmap(memblock+region_start, region_len) == 0;
  84             VERIFY(retval == 0, "munmap failed");
  85             ptr = mmap(memblock+region_start, region_len, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE | MAP_FIXED, -1, 0);
  86             VERIFY(ptr != 0, "mmap failed");
  87         }
  88     }
  89     return PERFINDEX_SUCCESS;
  90 }