diff options
Diffstat (limited to 'VNFs/DPPD-PROX/handle_lat.c')
| -rw-r--r-- | VNFs/DPPD-PROX/handle_lat.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/VNFs/DPPD-PROX/handle_lat.c b/VNFs/DPPD-PROX/handle_lat.c index 3962b21d..f6ecbf79 100644 --- a/VNFs/DPPD-PROX/handle_lat.c +++ b/VNFs/DPPD-PROX/handle_lat.c @@ -115,10 +115,16 @@ struct task_lat { FILE *fp_tx; struct prox_port_cfg *port; }; - -static uint32_t diff_or_zero(uint32_t a, uint32_t b) +/* This function calculate the difference between rx and tx_time + * Both values are uint32_t (see handle_lat_bulk) + * rx time should be higher than tx_time...except every UINT32_MAX + * cycles, when rx_time overflows. + * As the return value is also uint32_t, returning (rx_time - tx_time) + * is also fine when it overflows. + */ +static uint32_t diff_time(uint32_t rx_time, uint32_t tx_time) { - return a < b? 0 : a - b; + return rx_time - tx_time; } struct lat_test *task_lat_get_latency_meassurement(struct task_lat *task) @@ -257,7 +263,7 @@ static uint64_t lat_latency_buffer_get_min_tsc(struct task_lat *task) static uint64_t lat_info_get_lat_tsc(struct lat_info *lat_info) { - uint64_t lat = diff_or_zero(lat_info->rx_time, lat_info->tx_time); + uint64_t lat = diff_time(lat_info->rx_time, lat_info->tx_time); return lat << LATENCY_ACCURACY; } @@ -498,7 +504,7 @@ static void task_lat_store_lat(struct task_lat *task, uint64_t rx_packet_index, { if (tx_time == 0) return; - uint32_t lat_tsc = diff_or_zero(rx_time, tx_time) << LATENCY_ACCURACY; + uint32_t lat_tsc = diff_time(rx_time, tx_time) << LATENCY_ACCURACY; lat_test_add_latency(task->lat_test, lat_tsc, rx_error + tx_error); |