cellular-infrastructure
/
osmo-pcu
mirror of https://gerrit.osmocom.org/osmo-pcu
9
0
Fork 1
Code Issues Releases Wiki Activity

fix time-delta calculations for measurement reports 

The previous implementation unconditionally subtracted nanosecond
values from different time measurements, causing overflow if the
current measurement was taken in less of a fraction of a second
than the past measurement. Use timespecsub() instead, which
accounts for nanoseconds correctly.

Also, fix calculations of KBit/s throughtput. It was not being
calculated correctly, since it was actually accounting for one
KB per 128th-part-of-a-second.

Change-Id: I7d22e7b5902c230efeae66eb20c17026a4037887
Related: OS#3225
This commit is contained in:
Stefan Sperling 2018-05-31 12:28:55 +02:00
parent f0f7df1b87
commit 78ab624c2a
1 changed files with 14 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

31
src/gprs_rlcmac_meas.cpp
View File

@ -17,6 +17,8 @@
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <osmocom/core/timer_compat.h>
#include <gprs_rlcmac.h>
#include <gprs_debug.h>
#include <pcu_l1_if.h>
@ -72,15 +74,15 @@ int gprs_rlcmac_meas_rep(Packet_Measurement_Report_t *pmr)
int gprs_rlcmac_rssi(struct gprs_rlcmac_tbf *tbf, int8_t rssi)
{
struct timespec now_tv, *rssi_tv = &tbf->meas.rssi_tv;
uint32_t elapsed;
struct timespec elapsed;
tbf->meas.rssi_sum += rssi;
tbf->meas.rssi_num++;
osmo_clock_gettime(CLOCK_MONOTONIC, &now_tv);
elapsed = ((now_tv.tv_sec - rssi_tv->tv_sec) << 7)
+ (((now_tv.tv_nsec - rssi_tv->tv_nsec)/1000) << 7) / 1000000;
if (elapsed < 128)
timespecsub(&now_tv, rssi_tv, &elapsed);
if (elapsed.tv_sec < 1)
return 0;
gprs_rlcmac_rssi_rep(tbf);
@ -116,7 +118,7 @@ int gprs_rlcmac_received_lost(struct gprs_rlcmac_dl_tbf *tbf, uint16_t received,
uint16_t lost)
{
struct timespec now_tv, *loss_tv = &tbf->m_bw.dl_loss_tv;
uint32_t elapsed;
struct timespec elapsed;
uint16_t sum = received + lost;
/* No measurement values */
@ -129,10 +131,8 @@ int gprs_rlcmac_received_lost(struct gprs_rlcmac_dl_tbf *tbf, uint16_t received,
tbf->m_bw.dl_loss_received += received;
tbf->m_bw.dl_loss_lost += lost;
osmo_clock_gettime(CLOCK_MONOTONIC, &now_tv);
elapsed = ((now_tv.tv_sec - loss_tv->tv_sec) << 7)
+ (((now_tv.tv_nsec - loss_tv->tv_nsec)/1000) << 7) / 1000000;
if (elapsed < 128)
timespecsub(&now_tv, loss_tv, &elapsed);
if (elapsed.tv_sec < 1)
return 0;
gprs_rlcmac_lost_rep(tbf);
@ -169,21 +169,18 @@ int gprs_rlcmac_lost_rep(struct gprs_rlcmac_dl_tbf *tbf)
int gprs_rlcmac_dl_bw(struct gprs_rlcmac_dl_tbf *tbf, uint16_t octets)
{
struct timespec now_tv, *bw_tv = &tbf->m_bw.dl_bw_tv;
uint32_t elapsed;
struct timespec elapsed;
tbf->m_bw.dl_bw_octets += octets;
osmo_clock_gettime(CLOCK_MONOTONIC, &now_tv);
elapsed = ((now_tv.tv_sec - bw_tv->tv_sec) << 7)
+ (((now_tv.tv_nsec - bw_tv->tv_nsec)/1000) << 7) / 1000000;
if (elapsed < 128)
timespecsub(&now_tv, bw_tv, &elapsed);
if (elapsed.tv_sec < 1)
return 0;
tbf->m_bw.dl_throughput = (tbf->m_bw.dl_bw_octets/elapsed);
tbf->m_bw.dl_throughput = (tbf->m_bw.dl_bw_octets << 10) / ((elapsed.tv_sec << 10) + (elapsed.tv_nsec >> 20));
LOGP(DRLCMACMEAS, LOGL_INFO, "DL Bandwitdh of IMSI=%s / TLLI=0x%08x: "
"%d KBits/s\n", tbf->imsi(), tbf->tlli(),
tbf->m_bw.dl_bw_octets / elapsed);
"%d KBits/s\n", tbf->imsi(), tbf->tlli(), tbf->m_bw.dl_throughput);
/* reset bandwidth values timestamp */
memcpy(bw_tv, &now_tv, sizeof(*bw_tv));