time.c

   1 #include <time.h>
   2 #include <sys/time.h>
   3
   4 #include "fio.h"
   5
   6 static struct timeval genesis;
   7
   8 unsigned long utime_since(struct timeval *s, struct timeval *e)
   9 {
  10         long sec, usec;
  11
  12         sec = e->tv_sec - s->tv_sec;
  13         usec = e->tv_usec - s->tv_usec;
  14         if (sec > 0 && usec < 0) {
  15                 sec--;
  16                 usec += 1000000;
  17         }
  18
  19         sec *= (double) 1000000;
  20
  21         return sec + usec;
  22 }
  23
  24 unsigned long utime_since_now(struct timeval *s)
  25 {
  26         struct timeval t;
  27
  28         fio_gettime(&t, NULL);
  29         return utime_since(s, &t);
  30 }
  31
  32 unsigned long mtime_since(struct timeval *s, struct timeval *e)
  33 {
  34         long sec, usec;
  35
  36         sec = e->tv_sec - s->tv_sec;
  37         usec = e->tv_usec - s->tv_usec;
  38         if (sec > 0 && usec < 0) {
  39                 sec--;
  40                 usec += 1000000;
  41         }
  42
  43         sec *= (double) 1000;
  44         usec /= (double) 1000;
  45
  46         return sec + usec;
  47 }
  48
  49 unsigned long mtime_since_now(struct timeval *s)
  50 {
  51         struct timeval t;
  52         void *p = __builtin_return_address(0);
  53
  54         fio_gettime(&t, p);
  55         return mtime_since(s, &t);
  56 }
  57
  58 unsigned long time_since_now(struct timeval *s)
  59 {
  60         return mtime_since_now(s) / 1000;
  61 }
  62
  63 /*
  64  * busy looping version for the last few usec
  65  */
  66 void __usec_sleep(unsigned int usec)
  67 {
  68         struct timeval start;
  69
  70         fio_gettime(&start, NULL);
  71         while (utime_since_now(&start) < usec)
  72                 nop;
  73 }
  74
  75 void usec_sleep(struct thread_data *td, unsigned long usec)
  76 {
  77         struct timespec req, rem;
  78
  79         req.tv_sec = usec / 1000000;
  80         req.tv_nsec = usec * 1000 - req.tv_sec * 1000000;
  81
  82         do {
  83                 if (usec < 5000) {
  84                         __usec_sleep(usec);
  85                         break;
  86                 }
  87
  88                 rem.tv_sec = rem.tv_nsec = 0;
  89                 if (nanosleep(&req, &rem) < 0)
  90                         break;
  91
  92                 if ((rem.tv_sec + rem.tv_nsec) == 0)
  93                         break;
  94
  95                 req.tv_nsec = rem.tv_nsec;
  96                 req.tv_sec = rem.tv_sec;
  97
  98                 usec = rem.tv_sec * 1000000 + rem.tv_nsec / 1000;
  99         } while (!td->terminate);
 100 }
 101
 102 void rate_throttle(struct thread_data *td, unsigned long time_spent,
 103                    unsigned int bytes, int ddir)
 104 {
 105         unsigned long usec_cycle;
 106
 107         if (!td->rate)
 108                 return;
 109
 110         usec_cycle = td->rate_usec_cycle * (bytes / td->min_bs[ddir]);
 111
 112         if (time_spent < usec_cycle) {
 113                 unsigned long s = usec_cycle - time_spent;
 114
 115                 td->rate_pending_usleep += s;
 116                 if (td->rate_pending_usleep >= 100000) {
 117                         usec_sleep(td, td->rate_pending_usleep);
 118                         td->rate_pending_usleep = 0;
 119                 }
 120         } else {
 121                 long overtime = time_spent - usec_cycle;
 122
 123                 td->rate_pending_usleep -= overtime;
 124         }
 125 }
 126
 127 unsigned long mtime_since_genesis(void)
 128 {
 129         return mtime_since_now(&genesis);
 130 }
 131
 132 static void fio_init time_init(void)
 133 {
 134         fio_gettime(&genesis, NULL);
 135 }
 136
 137 void fill_start_time(struct timeval *t)
 138 {
 139         memcpy(t, &genesis, sizeof(genesis));
 140 }