diff options
| author | Pau Espin Pedrol <pespin@sysmocom.de> | 2021-07-22 13:25:05 +0200 |
|---|---|---|
| committer | Pau Espin Pedrol <pespin@sysmocom.de> | 2021-07-23 13:36:03 +0200 |
| commit | 56eda358741a871a519db52a7eae896af503a712 (patch) | |
| tree | f467ad91b29faed42930dd8ced40c2f16e467d96 /src/osmo-bsc/abis_rsl.c | |
| parent | 8e3320ac4835aa4b7cbe71ac3b3ccd4a7c07f20e (diff) | |
Introduce VTY option to forbid use of TCH for non-voicecall signalling
Usual allocation mechansim, when some signalling channel is needed,
first tries to reserve an SDCCH, and if all of them are exhausted, then
attempts to reserve a TCH as a last resort.
This, however, may cause TCH starvation under certain situations, for
instance if there high load on other services (LU, SMS, etc.).
Hence, it may be desirable for the operator to forbid reservation
of TCH slots once SDCCH become exhausted. This commit is thus adding a
VTY command which allows forbidding it. The default behavior (allow using
TCH timeslots when SDCCHs are exhausted) is kept as before.
The above mentioned prohibition is applied only to non-voicecall related
signalling services. That's because voicecall services will end up
requiring a TCH anyway, and forbidding reservation of TCH straighaway
when SDCCHs are exhausted would mean no voice calls could be initiated
while still TCHs would be available.
Related: SYS#5548
Change-Id: Ib08027125145df26602069bfb51847063b0ccc0c
Diffstat (limited to 'src/osmo-bsc/abis_rsl.c')
| -rw-r--r-- | src/osmo-bsc/abis_rsl.c | 24 |
1 files changed, 13 insertions, 11 deletions
diff --git a/src/osmo-bsc/abis_rsl.c b/src/osmo-bsc/abis_rsl.c index 8e4916dc0..d5b0d532e 100644 --- a/src/osmo-bsc/abis_rsl.c +++ b/src/osmo-bsc/abis_rsl.c @@ -2015,17 +2015,19 @@ void abis_rsl_chan_rqd_queue_poll(struct gsm_bts *bts) * in the code below, all other channel requests will get an SDCCH first * (if possible). */ - if (!lchan) { - LOG_BTS(bts, DRSL, LOGL_NOTICE, "CHAN RQD[%s]: no resources for %s 0x%x, retrying with %s\n", - get_value_string(gsm_chreq_descs, rqd->reason), gsm_lchant_name(GSM_LCHAN_SDCCH), - rqd->ref.ra, gsm_lchant_name(GSM_LCHAN_TCH_H)); - lchan = lchan_select_by_type(bts, GSM_LCHAN_TCH_H); - } - if (!lchan) { - LOG_BTS(bts, DRSL, LOGL_NOTICE, "CHAN RQD[%s]: no resources for %s 0x%x, retrying with %s\n", - get_value_string(gsm_chreq_descs, rqd->reason), gsm_lchant_name(GSM_LCHAN_SDCCH), - rqd->ref.ra, gsm_lchant_name(GSM_LCHAN_TCH_F)); - lchan = lchan_select_by_type(bts, GSM_LCHAN_TCH_F); + if (gsm_chreq_reason_is_voicecall(rqd->reason) || bts->chan_alloc_allow_tch_for_signalling) { + if (!lchan) { + LOG_BTS(bts, DRSL, LOGL_NOTICE, "CHAN RQD[%s]: no resources for %s 0x%x, retrying with %s\n", + get_value_string(gsm_chreq_descs, rqd->reason), gsm_lchant_name(GSM_LCHAN_SDCCH), + rqd->ref.ra, gsm_lchant_name(GSM_LCHAN_TCH_H)); + lchan = lchan_select_by_type(bts, GSM_LCHAN_TCH_H); + } + if (!lchan) { + LOG_BTS(bts, DRSL, LOGL_NOTICE, "CHAN RQD[%s]: no resources for %s 0x%x, retrying with %s\n", + get_value_string(gsm_chreq_descs, rqd->reason), gsm_lchant_name(GSM_LCHAN_SDCCH), + rqd->ref.ra, gsm_lchant_name(GSM_LCHAN_TCH_F)); + lchan = lchan_select_by_type(bts, GSM_LCHAN_TCH_F); + } } if (!lchan) { LOG_BTS(bts, DRSL, LOGL_NOTICE, "CHAN RQD[%s]: no resources for %s 0x%x\n", |