tools/tests/perf_index/stress_fault.c

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