Commit Graph

7 Commits

Author SHA1 Message Date
Philipp Maier 3632ffe65a timeslot_fsm: fix sourcecode indenting
Change-Id: I1cfd377cd8014e42aa45f9f0da664598ee88e02d
2023-02-28 10:01:50 +00:00
Neels Hofmeyr 8700803fa8 for linter: s/while(0)/while (0)
Change-Id: Ib422e7d1a7d543dcd8738581839ce55bb8fc29d2
2021-11-06 17:01:58 +01:00
Pau Espin 40c7410f9e Move ts_fsm_init to static constructor [3/4]
This allows having it initialized automatically, as we usually do with
this type of code. As a result, tests or other apps importing libbsc
don't need to take care of calling it.

NOTE: This fix is required by follow-up patches where some stubs are removed
and hence some tests start using FSMs internally. Since tests were not
using those FSMs before, there was no need to call ts_fsm_init().

This is one further step towards fixing interdependency mess of symbols
and stubs.

Change-Id: I0e4b95b5e73fbb3844d83ba33e66786831088e1f
2021-10-07 14:08:22 +02:00
Pau Espin 7974008436 bts_trx: Fix timeslot_fsm not properly freed during trx free() [1/4]
osmo_fsm_inst_free() must be called explicitly, otherwise the instance
is kept in the llist of instances and produces heap-use-after-free.

Note: This fix is required by follow-up patches where some stubs are removed
and hence some tests start using FSMs internally. Due to this bug, tests
will crash due to reason explain in previous paragraph.

This patch itself may introduced failures to build due to some new
interdependencies being introduced in same follow-up patches mentioned
above, which are in turn fixed by this present patch.
So they are expected to be merged together.

Change-Id: Ib0e5560efe518833f76f846d7269e82d85c186a1
2021-10-07 14:07:52 +02:00
Neels Hofmeyr e262919892 add fields to reflect nr of lchans in ts struct
So far the number of usable lchans is determined on-the-fly by the
physical channel config. With VAMOS, this becomes more complex, namely
determining whether the BTS is vamos capable.

Instead of calling a function to determine the number of lchans for
every use, rather place the number of valid lchans in int members of the
timeslot struct, and initialize those during timeslot setup.

Actual use of these new fields will follow in a subsequent patch, which
introduces the ts_for_n_lchans() macro to replace current lchan
iteration macros.

Related: SYS#5315 OS#4940
Change-Id: I08027d79db71a23e874b729c4e6173b0f269ee4f
2021-05-31 05:20:03 +00:00
Neels Hofmeyr dad4e7c3f7 fix TCH/H allocation: use half occupied dyn TS instead of switching more dyn TS
Change-Id: I5a8d943f31774af00664d037550be14e767d312a
2020-11-17 03:32:17 +01:00
Neels Hofmeyr 31f525e756 large refactoring: use FSMs for lchans; add inter-BSC HO
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
2018-07-28 12:18:23 +02:00