time.c

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