Place all code related to the object into the related file.
Having all the data model in one file made sense in early stage of
development to make progress quickly, but nowadays it hurts more than
helps, due to constantly growing size and more and more bits being
added to the model, gaining in complexity.
Currently, having lots of different objects mixed up in gsm_data.h is a hole
of despair, where nobody can make any sense were to properly put new stuff
in, ending up with functions related to same object in different files
or with wrong prefixes, declarations of non-existing functions, etc.
because people cannot make up their mind on strict relation to objects
in the data model.
Splitting them in files really helps finding code operating on a
specific object and helping with logically splitting in the future.
Change-Id: I00c15f5285b5c1a0109279b7ab192d5467a04ece
Fix neighbor config to match OsmoBSC manual: implement the plan for neighbor
configuration that was so far only described in the manual without actually
being in operation.
This first allows re-using ARFCN+BSIC pairs in and across BSS.
So far the handover_start() code always looked for handover target cells across
*all* local cells, even if they were not listed as neighbors to a source cell.
Imply all cells as neighbors only as long as there are no explicit neighbors
configured. As soon as the first 'neighbor' line appears in a 'bts' config,
only the listed neighbors are regarded as handover target cells. (The
'neighbor-list' commands are not related to this, only the relatively new
'neighbor (bts|lac|cgi|...)' commands affect actual handover procedures.)
TTCN3 tests TC_ho_neighbor_config_1 thru _7 play through the various aspects of
neighbor configuration: both the legacy implicit all-cells-are-neighbors as
well as allowing only explicit neighbors by config.
Related: OS#4056
Related: osmo-ttcn3-hacks Ia4ba0e75abd3d45a3422b2525e5f938cdc5a04cc
Change-Id: I29bca59ab232eddc74e0d4698efb9c9992443983
Implement basic support for inter-BSC HO from handover_decision_2: do inter-BSC
handover only when rxlev / rxqual / ta drop below the minimum requirements.
I considered adding a vty config flag to disable/enable remote-BSS handover,
but to avoid inter-BSC HO the user can simply refrain from configuring
neighbors for a particular cell.
In collect_assignment_candidate(), it is important to clear out any new
candidate entry. Hence adopt the same pattern as below: first compose a new
(cleared) candidate, then write the entry into the list.
Related: OS#3638
Change-Id: Id78ac1b2016998a2931a23d62ec7a3f37bb764c6
a) Prepare for triggering handover for any candidate, remote or local.
b) drop redundant arguments.
Change-Id: I5ba8b556703010c8e232b516285a837c999f87ef
Add FSMs:
- timeslot_fsm: handle dynamic timeslots and OML+RSL availability.
- lchan_fsm: handle an individual lchan activation, RTP stream and release,
signal the appropriate calling FSMs on success, failure, release.
- mgw_endpoint_fsm: handle one entire endpoint with several CI.
- assignment_fsm: BSSMAP Assignment Request.
- handover_fsm: all of intra, inter-MO and inter-MT handover.
Above FSMs absorb large parts of the gscon FSM. The gscon FSM was surpassing
the maximum amount events (32), and it is more logical to treat assignment,
handover and MGW procedures in separate FSMs.
- Add logging macros for each FSM type:
- LOG_TS()
- LOG_LCHAN()
- LOG_MGWEP(), LOG_CI()
- LOG_ASSIGNMENT()
- LOG_HO()
These log with the osmo_fsm_inst where present.
New style decision: logging without a final newline char is awkward,
especially for gsmtap logging and when other logs interleave LOGPC() calls;
we have various cases where the final \n goes missing, and also this invokes
the log category checking N times instead of once.
So I decided to make these macros *always* append a newline, but only if
there is no final newline yet. I hope that the compiler optimizes the
strlen() of the constant format strings away. Thus I can log with or without
typing "\n" and always get an \n termination anyway.
General:
- replace osmo_timers, state enums and program-wide osmo_signal_dispatch()
with dedicated FSM timeouts, states and events.
- introduce a common way to handle Tnnn timers: gsm_timers.h/.c: struct T_def.
These can be used (with some macro magic) to define a state's timeout once,
and not make mistakes for each osmo_fsm_inst_state_chg().
Details:
bsc_subscr_conn_fsm.c:
- move most states of this FSM to lchan_fsm, assignment_fsm, handover_fsm and
mgw_endpoint_fsm.
- There is exactly one state for an ongoing Assignment, with all details
handled in conn->assignment.fi. The state relies on the assignment_fsm's
timeout.
- There is one state for an ongoing Handover; except for an incoming Handover
from a remote BSS, the gscon remains in ST_INIT until the new lchan and conn
are both established.
- move bssmap_add_lcls_status() to osmo_bsc_lcls.c
abis_rsl.c:
- move all dynamic timeslot logic away into timeslot_fsm. Only keep plain send/receive functions in
abis_rsl.c
- reduce some rsl functions to merely send a message, rename to "_tx_".
- rsl_ipacc_mdcx(): add '_tx_' in the name; move parts that change the lchan state out into the
lchan_fsm, the lchan->abis_ip.* are now set there prior to invoking this function.
- move all timers and error/release handling away into various FSMs.
- tweak ipa_smod_s_for_lchan() and ipa_rtp_pt_for_lchan() to not require an
lchan passed, but just mode,type that they require. Rename to
ipacc_speech_mode*() and ipacc_payload_type().
- add rsl_forward_layer3_info, used for inter-BSC HO MO, to just send the RR
message received during BSSMAP Handover Command.
- move various logging to LOG_LCHAN() in order to log with the lchan FSM instance.
One drawback is that the lchan FSM is limited to one logging category, i.e. this moves some logging
from DRR to DRSL. It might actually make sense to combine those categories.
- lose LOGP...LOGPC logging cascades: they are bad for gsmtap logging and for performance.
- handle_classmark_chg(): change logging, move cm2 len check out of the cm3 condition (I hope that's
correct).
- gsm48_send_ho_cmd(): split off gsm48_make_ho_cmd() which doesn't send right away, so that during
inter-bsc HO we can make an RR Handover Command to send via the MSC to the remote BSS.
assignment_fsm.c:
- the Chan Mode Modify in case of re-using the same lchan is not implemented
yet, because this was also missing in the previous implementation (OS#3357).
osmo_bsc_api.c:
- simplify bsc_mr_config() and move to lchan_fsm.c, the only caller; rename to
lchan_mr_config(). (bsc_mr_config() used to copy the values to mr_bts_lv
twice, once by member assignment and then again with a memcpy.)
- During handover, we used to copy the MR config from the old lchan. Since we
may handover between FR and HR, rather set the MR Config anew every time, so
that FR rates are always available on FR lchans, and never on HR lchans.
Depends: I03ee7ce840ecfa0b6a33358e7385528aabd4873f (libosmocore),
I1f2918418c38918c5ac70acaa51a47adfca12b5e (libosmocore)
Change-Id: I82e3f918295daa83274a4cf803f046979f284366
Move all of libbsc/ into osmo-bsc/, and separate/move some implementations to
allow linking from utils/* and ipaccess/* without pulling in unccessary
dependencies.
Some utilities use gsm_network and gsm_bts structs, which already include data
structures for fairly advanced uses. Move initialization that only osmo-bsc
needs into new bsc_network_init() and bsc_bts_alloc_register() functions, so
that the leaner tools can use the old gsm_* versions without the need to link
everything (e.g. handover and lchan alloc code).
In some instances, there need to be stubs if to cut off linking "just before
the RSL level" and prevent dependencies from creeping in.
- abis_rsl_rcvmsg(): the only program currently interpreting RSL messages is
osmo-bsc, the utils are merely concerned with OML, if at all.
- paging_flush_bts(): ip.access nanobts models call this when the RSL link is
dropped. Only osmo-bsc actually needs to do anything there.
- on_gsm_ts_init(): the mechanism to trigger timeslot initialization is related
to OML, while this action to take on init would pull in RSL dependencies.
utils/ and ipaccess/ each have a stubs.c file to implement these stubs. Tests
implement stubs inline where required.
From src/utils/, src/ipaccess/ and tests/*/, link in .o files from osmo-bsc/.
In order for this to work, the osmo-bsc subdir must be built before the other
source trees. (An alternative would be to include the .c files as sources, but
that would re-compile them in every source tree. Not a large burden really, but
unless linking .o files gives problems, let's have the quicker build.)
Minor obvious cleanups creep in with this patch, I will not bother to name them
individually now unless code review asks me to.
Rationale:
1) libbsc has been separate to use it for osmo-nitb and osmo-bsc in the old
openbsc.git. This is no longer required, and spreading over libbsc and osmo-bsc
is distracting.
2) Recently, ridiculous linking requirements have made adding new functions
cumbersome, because libbsc has started depending on osmo-bsc/*.c
implementations: on gscon FSM and bssap functions. For example, neither
bs11_config nor ipaccess-config nor bts_test need handover_cfg or BSSMAP
message composition. It makes no sense to link the entire osmo-bsc to it, nor
do we want to keep adding stubs to each linking realm.
Change-Id: I36a586726f5818121abe54d25654819fc451d3bf
Pau Espin
Martin Hauke
Neels Hofmeyr