common/utils/bench.h

   1 /* libnbd
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  31  */
  32
  33 #ifndef LIBNBD_BENCH_H
  34 #define LIBNBD_BENCH_H
  35
  36 #include <sys/time.h>
  37
  38 #define MICROSECONDS 1000000
  39
  40 struct bench {
  41   struct timeval start, stop;
  42 };
  43
  44 static inline void
  45 bench_start (struct bench *b)
  46 {
  47   gettimeofday (&b->start, NULL);
  48 }
  49
  50 static inline void
  51 bench_stop (struct bench *b)
  52 {
  53   gettimeofday (&b->stop, NULL);
  54 }
  55
  56 static inline double
  57 bench_sec (struct bench *b)
  58 {
  59   struct timeval dt;
  60
  61   dt.tv_sec = b->stop.tv_sec - b->start.tv_sec;
  62   dt.tv_usec = b->stop.tv_usec - b->start.tv_usec;
  63
  64   if (dt.tv_usec < 0) {
  65     dt.tv_sec -= 1;
  66     dt.tv_usec += MICROSECONDS;
  67   }
  68
  69   return ((double)dt.tv_sec * MICROSECONDS + dt.tv_usec) / MICROSECONDS;
  70 }
  71
  72 #endif /* LIBNBD_BENCH_H */