Method record

runtime/TimeTrace.cc:125–147

* Record an event in the buffer. * * \param timestamp * Identifies the time at which the event occurred. * \param format * A format string for snprintf that will be used, along with * arg0..arg3, to generate a human-readable message describing what * happened, when the time trace is printed. The message is generated * by calling snprintf as follows: * snprint

 *      Argument to use when printing a message about this event.
 */
void TimeTrace::Buffer::record(uint64_t timestamp, const char* format,
        uint32_t arg0, uint32_t arg1, uint32_t arg2, uint32_t arg3)
{
    if (activeReaders > 0) {
        return;
    }

    Event* event = &events[nextIndex];
    nextIndex = (nextIndex + 1) & BUFFER_MASK;

    // There used to be code here for prefetching the next few events,
    // in order to minimize cache misses on the array of events. However,
    // performance measurements indicate that this actually slows things
    // down by 2ns per invocation.
    // prefetch(event+1, NUM_PREFETCH*sizeof(Event));

    event->timestamp = timestamp;
    event->format = format;
    event->arg0 = arg0;
    event->arg1 = arg1;
    event->arg2 = arg2;
    event->arg3 = arg3;
}

/**
 * Return a string containing a printout of the records in the buffer.