LttTime prev_event_time; //the time of the previous event
LttCycleCount pre_cycle_count; //previous cycle count of the event
int count; //the number of overflow of cycle count
+ gint64 overflow_nsec; //precalculated nsec for overflows
/* end of workaround */
};
void * cur_event_pos; //the position of the current event
void * buffer; //the buffer containing the block
double nsec_per_cycle; //Nsec per cycle
+ guint64 one_overflow_nsec; //nsec for one overflow
+ gint64 overflow_nsec; //precalculated nsec for overflows
+ //can be negative to include value
+ //of block start cycle count.
+ //incremented at each overflow while
+ //reading.
//LttCycleCount cycles_per_nsec_reciprocal; // Optimisation for speed
unsigned cur_heart_beat_number; //current number of heart beat in the buf
LttCycleCount cur_cycle_count; //current cycle count of the event
LttTime prev_event_time; //the time of the previous event
LttCycleCount pre_cycle_count; //previous cycle count of the event
int count; //the number of overflow of cycle count
+ gint64 overflow_nsec; //precalculated nsec for overflows
/* end of workaround */
};
t->prev_event_time = ep->prev_event_time;
t->pre_cycle_count = ep->pre_cycle_count;
t->count = ep->count;
+ t->overflow_nsec = ep->overflow_nsec;
/* end of workaround */
//update the fields of the current event and go to the next event
event->prev_event_time = t->prev_event_time;
event->pre_cycle_count = t->pre_cycle_count;
event->count = t->count;
+ event->overflow_nsec = t->overflow_nsec;
+
/* end of workaround */
*/
getCyclePerNsec(tf);
/* we are at end position, make end time more precise */
+ /* Start overflow_nsec to a negative value : takes account of the
+ * start of block cycle counter */
+ tf->overflow_nsec = (-((double)tf->a_block_start->cycle_count)
+ * tf->nsec_per_cycle);
+ /* put back the numbers corresponding to end time */
+ tf->overflow_nsec += tf->one_overflow_nsec * tf->count;
+
tf->a_block_end->time = getEventTime(tf);
//g_debug("precalculating cycles end for block %i", whichBlock);
tf->cur_heart_beat_number = 0;
/* Make start time more precise */
+ /* Start overflow_nsec to a negative value : takes account of the
+ * start of block cycle counter */
+ tf->overflow_nsec = (-((double)tf->a_block_start->cycle_count)
+ * tf->nsec_per_cycle);
+
+
tf->a_block_start->time = getEventTime(tf);
/* recalculate the cycles per nsec, with now more precise start and end time
*/
getCyclePerNsec(tf);
+ tf->overflow_nsec = (-((double)tf->a_block_start->cycle_count)
+ * tf->nsec_per_cycle);
+
+
tf->current_event_time = getEventTime(tf);
tf->prev_event_time.tv_sec = 0;
tf->prev_event_time.tv_nsec = 0;
+ tf->count = 0;
+
+ tf->overflow_nsec = (-((double)tf->a_block_start->cycle_count)
+ * tf->nsec_per_cycle);
+
}
/*****************************************************************************
lBufTotalNSec = ltt_time_to_double(lBufTotalTime);
t->nsec_per_cycle = (double)lBufTotalNSec / (double)lBufTotalCycle;
+ /* Pre-multiply one overflow (2^32 cycles) by nsec_per_cycle */
+ t->one_overflow_nsec = t->nsec_per_cycle * (double)0x100000000ULL;
+
/* See : http://www.azillionmonkeys.com/qed/adiv.html */
// precalculate the reciprocal, so divisions will be really fast.
// 2^32-1 == 0xFFFFFFFFULL
{
LttTime time;
LttCycleCount cycle_count; // cycle count for the current event
- LttCycleCount lEventTotalCycle; // Total cycles from start for event
- LttCycleCount lEventNSec; // Total nsecs from start for event
+ //LttCycleCount lEventTotalCycle; // Total cycles from start for event
+ gint64 lEventNSec; // Total nsecs from start for event
LttTime lTimeOffset; // Time offset in struct LttTime
guint16 evId;
if(unlikely(comp_count)) {
/* Wrapped */
- tf->count++; //increment wrap count
+ tf->overflow_nsec += tf->one_overflow_nsec;
+ tf->count++; //increment overflow count
}
//if(unlikely(cycle_count < tf->pre_cycle_count)) tf->count++;
// cycle_count += (tf->cur_heart_beat_number - tf->count) << 32;
//tf->cur_cycle_count = tf->cur_cycle_count + res_delta_count;
+ //
+ //
// Total cycle counter of the event.
- tf->cur_cycle_count = cycle_count | ((LttCycleCount)tf->count << 32);
+ //tf->cur_cycle_count = cycle_count | ((LttCycleCount)tf->count << 32);
//g_debug("cur cycle count %llu", tf->cur_cycle_count);
// Total number of cycles since the beginning of the block
- lEventTotalCycle = tf->cur_cycle_count
- - tf->a_block_start->cycle_count;
+ //lEventTotalCycle = tf->cur_cycle_count
+ // - tf->a_block_start->cycle_count;
lEventTotalCycle -= tf->a_block_start->cycle_count;
#endif //0
// Convert it to nsecs
- lEventNSec = (double)lEventTotalCycle * (double)tf->nsec_per_cycle;
+ //lEventNSec = (double)lEventTotalCycle * (double)tf->nsec_per_cycle;
//lEventNSec = (tf->cycles_per_nsec_reciprocal * lEventTotalCycle) >> 16;
// Determine offset in struct LttTime
- lTimeOffset = ltt_time_from_double(lEventNSec);
-
+ //lTimeOffset = ltt_time_from_double(lEventNSec);
+ //
+ // We do not substract block start cycle count here, it has already been done
+ // on the overflow_nsec
+ // The result should never be negative, because the cycle count of
+ // the event following the block start should be >= the previous one.
+ lEventNSec = (gint64)((double)cycle_count * tf->nsec_per_cycle)
+ +tf->overflow_nsec;
+ //g_assert(lEventNSec >= 0);
+ lTimeOffset = ltt_time_from_uint64(lEventNSec);
+
time = ltt_time_add(tf->a_block_start->time, lTimeOffset);
return time;