When the SDCCH gets released while the TCH still beeing activated, then
the ChanActivACK that is received after the TCH is activated will trigger
a segmentation fault in the assignment_fsm. The reason for this is that
conn->lchan, which holds the SDCCH at that point in time, is now NULL.
To prevent osmo-bsc from crashing, the FSM should check for the presence
of conn->lchan first. If it does not exist, the FSM should terminate.
(Assignment failed)
Change-Id: I3b1cd88bea62ef0032f6c035bac95d3df9fdca7a
Related: SYS#5627
Changing the BTS type is not supported, so don't allow it.
For example, Changing from type sysmobts to type rbs2000
may hit an OSMO_ASSERT in om2k_bts_fsm_alloc()
The default BTS type if osmo-bsc is started with an empty
configuration and the operator issues config terminal->network->bts 0
will be "unknown". This type and only this type can be
changed from the vty config node.
Change-Id: I0df97ef128a1bbd84c787654d1d842dce4dad819
The function is not really handover specific, and will be used in other
places in subsequent patches.
Change-Id: Icae8b9045e497f850f22cb3b6f93acbf61b84746
Many years prior to the implementation of osmo-cbc, we introduced
a way how raw RSL SMSCB COMMANMD can be injected from the VTY.
These days, people should use the CBSP interface with osmo-cbc or any
other CBC. We should not advertise the VTY command hack
as a standard feature anymore.
Change-Id: If5ddc3db989763a1f47d4cbc026e293e3134d8ef
Related: OS#4753
So far osmo-bsc would enable Uplink DPC (Dynamic Power Control) only
for osmo-bts, and the 'static' mode for all other BTS models. This
decision dates back to the time when ip.access specific encoding for
dynamic power control parameters was not implemented, and the MS
Power Parameters IE was sent empty in the RSL messages.
Let's make a step forward by enabling Uplink DPC by default for
all BTS models which declare the API for vendor-specific encoding
of the power control parameters. Currently this includes osmo-bts
and nanoBTS, both supporting ip.access specific format.
Change-Id: If86d27d4332af3d82f862737340d061e42e34eba
Related: SYS#4918
On lchan activation, we already know the Timing Advance in most
situations: from the Channel Request RACH, or from a previous lchan in
the same cell. Place this information in lchan->activate.info.ta.
So far, the lchan->last_ta (until recently called rqd_ta) was used to
store the initial TA for channel activation -- move the initial TA to
lchan->activate.info.ta, for proper scoping.
Only an inter-cell handover does not yet know a Timing Advance (until
the Handover Detection RACH is received), so indicate
activate.info.ta_known = false for that case.
If ta_known is false, do not include an Access Delay IE in the Channel
Activation message, ensuring that the BTS does not use an arbitrary TA
that is likely inaccurate.
The effect for OsmoBTS is that we will *not* start the downlink SACCH on
channel activation for inter-cell handover, but will wait for a HO RACH
first, and then use the correct TA when enabling downlink SACCH.
Related: OS#4008 SYS#5192
Change-Id: I986bf93e8acd6aef7eaf63ac962480b680aa894f
Originally, the lchan stored only the Timing Advance from the initial
channel request, hence it was called rqd_ta.
Since quite a while now, rqd_ta also stores the most recent Timing
Advance from each received Measurement Report. So rename to last_ta.
This is cosmetic preparation for an upcoming patch that clarifies
whether the Timing Advance is already known for Channel Activation.
Change-Id: I1049526a173819baeb4978db5bf018ba3f1006a0
This is a non-standard RSL message that must be sent after each traffic
channel has been established. Without it, any voice call will be
disconnected within seconds.
This is a hack; we need to store the subscribers classmark2 value and
use it here.
Change-Id: I6cb6d25e405aa888c4df4022d897330a6af9e946
Related: OS#2389
This is required in order to tell MS that osmo-pcu now supports
Network Assisted Cell Change (NACC).
Other BTS are not enabled by default since NACC support is not known to
work nor tested there.
Depends: libosmocore.git Change-Id I61991266b95d0c13d51b47906cc07846e9cf1390
Related: SYS#4909
Change-Id: If91d85331d402c3ab9c32b70c2c66cd7ba6ceb28
We cannot simply use the highest 'x' in A5/x codecs.
For A5/7 through A5/3, larger 'x' means better.
But: A5/1 is better than A5/2, so we need to prefer the former
over the latter.
Change-Id: I399fff8d07d1bfcbc6b385e90914ff6d9e00eb73
Closes: OS#4975
If an emergency call arrives at the BSC while all TCH are busy, one TCH
is cleared in favor of the emergency call. However, if emergency calls
are disabled (system information), it is still possible that an MS might
try an emergency call anyway or that due to interference a regular call
might look like an emergency call (channel request reason). In those
cases the preemption must not happen and the emergency call must be
rejected.
Change-Id: I1af1f4fefcbe6a886bb5396901ce0cb2368a0e19
Related: OS#4976
When setting the BER threshold for ACCH repetition the VTY displays
wrong threshold values in the online help.
Change-Id: I4c89ad130da328aba99663e5a2931a4007772bca
Related: SYS#5114
When balancing congestion, not only look at TCH/F or TCH/H separately,
but also to take into account the effects on the other TCH kind from
using/freeing dynamic TS.
Related: OS#5298
Change-Id: I433df6f343650f9056b1bab926bc19ac1d867ad5
Add bool log argument to lchan_avail_by_type() and omit logging when
passed as false. From handover_decision_2.c, pass 'log' as false, from
all other callers pass true, i.e. for unchanged behavior.
Rationale:
Usually, we use lchan_avail_by_type() to select a new lchan to initiate
actual service. For that, it is interesting to see how osmo-bsc decides
which lchan will be used.
For handover decision 2, we since recently call lchan_avail_by_type()
for each and every handover candidate, to determine whether it will
occupy a dynamic timeslot or not (to know whether we would congest the
other TCH kind). So this happens for each permutation of source lchan
and target cell. That produces a lot of logging, out of proportion of
being useful to the maintainer.
Change-Id: Ia403f8fc853ca9ea9e81f7a7395df6b23845ebed
For handover algorithm 2, properly figure out what effects the target
cell will see for the *other* TCH kind when a handover would occupy a
dynamic timeslot.
Before this, only TCH/F or TCH/H would be regarded at a time. This
introduces detection of whether a dynamic timeslot would be occupied by
a handover, and how losing one unused dynamic timeslot affects the
congestion situation for the TCH kind that is not targeted by the
handover.
In other words, if a handover to TCH/F causes congestion in TCH/H
because of a dynamic timeslot becoming occupied, the handover will not
be performed. Before this, oscillation situations could occur.
A subsequent patch will do the same for congestion balancing.
Related: SYS#5297
Change-Id: I1536b60f03cb0aeb6ba14a72b518aec82fa572fe
The following message makes no sense:
DRLL DEBUG gsm_data.c:844 MS Power class update: 4 -> 4
because nothing really changed, MS Power class remains 4. Neither
it makes sense to call lchan_update_ms_power_ctrl_level().
Change-Id: I519d2d1575cbb5352cc381a60513db8e0e2cb0a0
Allocating a new list of supported codecs *before* checking the
command arguments is a bad idea. The operator may simply mistype
one of the codecs and will end up with a list of NULL pointers.
The functions calling audio_support_to_gsm88() assume that this
list always does contain valid pointers, so if a new subscriber
connection gets established, or the operator simply invokes
'show running-config', osmo-bsc would crash due to NULL pointer
dereference.
Steps to reproduce:
1. In the VTY, do: 'en' -> 'configure terminal' -> 'msc';
2. Configure any invalid codec list, e.g. 'codec-list Boom!';
3. Invoke 'show running-config', boom!
Let's check the input before changing the internal structures.
Change-Id: I35b740a39c9cf3716d286e717486ef505bc61522
Fixes: OS#4946
My assumption that lchan_reset() is called on CHANnel ACTIVation
was wrong - it's actually called on CHANnel RELease. Therefore
(re)setting per-lchan BS power value must be done in the other
function that is responsible for channel activation.
Change-Id: I056c448ce017458dc4a004374ddca86d44dc35b4
Related: SYS#4918
config_write_bts_gprs() currently writes the remote address of an
NSVC even if osmo_sockaddr_str_from_sockaddr() returns non-zero
code. Thus saving a configuration with only one configured NSVC
to a file would produce the following:
bts N
...
gprs nsvc 0 nsvci 101
gprs nsvc 0 local udp port 23023
gprs nsvc 0 remote ip 127.0.0.1
gprs nsvc 0 remote udp port 23000
gprs nsvc 1 nsvci 0
gprs nsvc 1 local udp port 0
gprs nsvc 1 remote ip
and next time osmo-bsc would refuse to start due to:
Error occurred during reading the below line:
gprs nsvc 1 remote ip
The related condition consists of the following two parts:
- checking if osmo_sockaddr_str_from_sockaddr() != 0;
- checking if 'remote.af != AF_UNSPEC'.
The first one is wrong, because osmo_sockaddr_str_from_sockaddr(),
like many other functions, returns 0 on success. Let's fix this.
After the fix, the second part does not seem to make sense, because
remote.af would remain AF_UNSPEC (0) if the function call succeeds.
Printing the remote port alone does not make sense, let's avoid
printing it if the address cannot be parsed into a string.
Change-Id: I5d6cbde4f605c8184db4ade87de5644a849c05db
Fixes: I621360cab1e12c22248e33d62a9929995053ce04
For balancing load across congested cells and across congested TCH/*
kinds, instead of comparing the number of lchans above the configured
congestion threshold, compare the percent of lchans of overload.
In short, using a percentage prevents cells with less min-free-slots to
fill up 100% while neighbor cells still may have several free lchans
available.
An obvious example of why this is desirable is illustrated by
test_balance_congestion_by_percentage.ho_vty:
Cell A has min-free-slots 2, and has all slots occupied.
Cell B has min-free-slots 4, and has 2 slots remaining free.
If we count congested lchans as in current master: cell A has a
congestion count of 2: two more lchans in use than "allowed". If we move
one lchan over to cell B, it ends up with a congestion count of 3, which
is worse than 2. So when counting lchans, we decide that cell A should
remain full.
Instead, when comparing percentage of remaining lchans, we would see
that cell A is loaded 100% above congestion (2 of 2 remaining lchans in
use), but when moving one lchan to cell B, that would only be 75% loaded
above its treshold (3 of 4 remaining lchans in use). So a percentage
comparison would cause a handover to cell B.
Related: SYS#5259
Change-Id: I55234c6c99eb02ceee52be0d7388bea14304930f
This new CTRL interface allows users of this BSC (such as attached PCU)
to gather neighbor information.
This interface is needed for PCU to translate ARFCN+BSIC keys provided
by MS in the Um side into CGI + RAC keys used to identify target cells
in RIM procedures against SGSNs on the Gb interface.
This patch extends the already existing neighbor information storage in
the VTY by allowing storage of CGI + RAC (RAC couldn't be stored
beforehand).
Related: SYS#4909
Depends: libosmocore.git Change-Id If48f412c32e8e5a3e604a78d12b74787a4786374
Change-Id: Ib07c9d23026332a207d4b7a0f7b4e76c0094e379
When evenly distributing congestion across cells, count the number of
occupied lchans surpassing congestion, and not the overall number of
free lchans -- which disregards congestion thresholds.
Fix the bugs shown by
test_congestion_no_oscillation.ho_vty
test_balance_congestion_tchf_tchh.ho_vty
This implements a simple calculation for congestion load by counting
lchans in use above congestion. An improvement of this calculation
using percent follows in I55234c6c99eb02ceee52be0d7388bea14304930f.
Related: SYS#5259
Change-Id: Icb373dc6bfc9819446db5e96f71921781fe2026d
Store the number of free lchans and the min-free-slots settings in
ho_candidate, instead of figuring those out in various places, to make
it easier to read.
Prepare for upcoming patch which also requires these values to fix a
bug.
Change-Id: Ie6ca5af5e8d0ebb8deaaaa637e2728008ecba517
So far it is often confusing which cell a specific member refers to.
Clarify lchan, bts, ... to current.lchan, target.bts, ...
Also move the rxlev_{current,target} to {current,target}.rxlev.
Eliminate numerous local variables to make it easier to read which side
is being used (e.g. "c->target.bts" instead of just "bts").
No functional change.
Change-Id: I06898eb745a5be548df0b76fa760ce790cfab3ed
Fix flaws in picking a candidate for congestion resolution, shown in
recently added tests.
- For TCH/H->TCH/F upgrading, do not favor moving to a weaker neighbor
cell.
- When comparing dynamic timeslots on the same cell, favor a dynamic
timeslot that frees an entire dyn TS even though the target rxlev
differs.
Do not separate the passes for inter-cell and intra-cell candidates:
before, the inter-cell pass would already pick a candidate and start
handover, even though the subsequent intra-cell pass would have revealed
a better candidate. Join the intra-cell considerations into
pick_better_lchan_to_move().
The intra-cell pass was separate, because it would find the *weakest*
current rxlev, to give a TCH/H to TCH/F upgrade to the currently weakest
lchan.
Instead of the separate pass for weakest rxlev, in addition to the
target cell's rxlev, also consider the rxlev *change* in
pick_better_lchan_to_move(): For candidates that do not change the rxlev
(usually those that stay in the same cell) and that upgrade to TCH/F,
favor a candidate with weaker current rxlev.
Completely revisit the conditions in pick_better_lchan_to_move() to
yield the desired prioritization of candidate preferences.
In three handover tests, remove the "FAIL" comments and adjust to now
expect the actually desired behavior.
Related: SYS#5032
Change-Id: I2704899c85c35dfd4eba43468452483f40016ca2
Instead of passing the TCH/H -> TCH/F bias (AFS bias) in local
variables, rather store it in the ho_candidate struct next to the other
rxlev related values.
Add the AFS bias to the compared rxlev in pick_better_lchan_to_move().
Modify pick_better_lchan_to_move() to simpler semantics of returning
either a or b.
No functional change.
Change-Id: I73860abdf2a77270ca4851ad58c09767d1bb08f1
Store the rxlev of the current lchan and the target BTS in the
ho_candidate, to clarify the code.
No functional change, cosmetically prepare for
I2704899c85c35dfd4eba43468452483f40016ca2.
Change-Id: Ie6c165e17bb3c99eebc967a6bb02529db8bdfc98
In handover_decision_2.c, instead of repeating a similar loop four
times, put that loop in a function and parameterize it.
Prepare for a fix of two problems in handover decision 2, see
I2704899c85c35dfd4eba43468452483f40016ca2.
Change-Id: I7c32d08e490a88a7f044b0a71dc4b07d748dd572
Adding SMSCB messages to a BTS so far only worked if there were
existing messages with a lower scheduling period than the new message.
Before this patch, it fails for new messages if they are of equal or
lower scheduling period than the existing messages.
Change-Id: I69a05b22200b3a1ee406b0673553e135603d723b
None of those commands apply immediately, they only affect newly
established logical channels. The reason is that the related
IEs are only getting sent on channel activation / assignment.
Change-Id: I06c7851115fb31d1eb92c400d9724f4f051bd171
Related: SYS#5114
Philipp Maier
Vadim Yanitskiy
Keith Whyte
Pau Espin Pedrol
Harald Welte
Pau Espin