add_stat_sample(&ts->slat_stat[ddir], usec);
if (td->slat_log)
add_log_sample(td, td->slat_log, sample_val(usec), ddir, bs, offset);
add_stat_sample(&ts->slat_stat[ddir], usec);
if (td->slat_log)
add_log_sample(td, td->slat_log, sample_val(usec), ddir, bs, offset);