follow-up to I9ad094d272254d7aee9b0a676201d4ed8cd727ca because it was merged
before fixeria's code review could be incorporated.
Change-Id: I474cf1a58d1f00ec5b0ae52bd095a60aad763975
Set flag lchan->activate.immediate_assignment_sent to true when sending, and
omit a reject after that.
lchan->activate gets completely zeroed in lchan_reset(), which sets that flag
back to false whenever an lchan becomes inactive.
Related: OS#3709
Change-Id: I9ad094d272254d7aee9b0a676201d4ed8cd727ca
Put all lchan release related flags and settings in a sub-struct named
'release' to better indicate what those fields are for. There is no functional
change.
Change-Id: Icfddc6010e5d7c309f1a7ed3526b5b635ffeaf11
If an lchan is being released and had a SACCH active, there is no reason to
omit the Deact SACCH message ever. All of the callers that passed
do_deact_sacch = false did so for no good reason.
Drop the do_deact_sacch flag everywhere and, when the lchan type matches and
SAPI[0] is still active, simply always send a Deact SACCH message.
The do_deact_sacch flag was carried over from legacy code, by me, mainly
because I never really understood why it was there. I do hope I'm correct now,
asserting that having this flag makes no sense.
Change-Id: Id3301df059582da2377ef82feae554e94fa42035
In the case where there is a release in error and we skip immediately to the RF
Release state, send all of Deact SACCH, RR Release messages and also signal the
lchan_rtp_fsm as appropriate.
Move that code to static lchan_do_release() and call from both
lchan_fsm_wait_rll_rtp_released_onenter() in the normal case, as well as
lchan_release() when skipping that.
When releasing in error, but we're already in LCHAN_ST_WAIT_RLL_RTP_RELEASED,
those messages have already been sent and we can skip them.
Change-Id: I648a9826ce56b611359f81462ca03e4ab4c736aa
After commit [1], the code makes sure to disassociate lchan and conn before
invoking the lchan release. However, we only send RR Release if a conn is
present, which clearly is nonsense after [1].
[1] commit 8b818a01b0
"subscr conn: properly forget lchan before release"
Change-Id: I4fd582b41ba4599af704d670af83651d2450b1db
Manage sending of RR Release via a flag, set during invoking lchan release.
Add do_rr_release arg to lchan_release(), gscon_release_lchans(). In
lchan_fsm.c, send RR Release only if do_rr_release was passed true; do not care
whether a conn is still associated (because it won't ever be since [1]).
That way we can intelligently decide what release process makes sense (whether
the lchan terminates the subscriber connection or whether the connection goes
on at another lchan), and still disassociate lchan and conn early.
BTW, this problem wasn't caught by the stock OsmoBSC TTCN3 tests, because the
f_expect_chan_rel() don't care whether an RR Release happens or not. This is
being fixed by Ibc64058f1e214bea585f4e8dcb66f3df8ead3845.
So far this patch should fix BSC_Tests_LCLS.TC_lcls_connect_clear.
Related: OS#3413
Change-Id: I666b3b4f45706d898d664d380bd0fd2b018be358
When reading the log of OS#3686, I wished for explicit logging of when exactly
an lchan disassociates from a conn. Here is the debug logging I would have
liked to see.
I'm not sure whether we really need to merge this patch...
Change-Id: I97558b899e7f2578ba98287e7352dc072d02ce44
lchan_fsm_wait_rf_release_ack_onenter() calls gscon_forget_lchan(). At the
point where the conn has no lchan, the lchan must not have a conn. Make sure
that conn is NULL after gscon_forget_lchan().
I hope this fixes OS#3686, it is the only situation I could find where the
disassociation is potentially one-sided.
I get the feeling that this should be hardcoded in gscon_forget_lchan(), but I
dimly remember other situations that are less trivial, where it doesn't
necessarily make sense to forget reciprocically. So only fixing this one now.
Related: OS#3686
Change-Id: If0c6e495e419b9dbb44443c3fc3f54dd4b714aa5
Right below this call, we invoke lchan_reset(), and the first thing it does is
gscon_forget_lchan(). Drop this redundant invocation.
Change-Id: I503efceb6d34c8df0cdfef3dfc83fa1e61271c47
During the generation of the multirate configuration IE in the channel
activation message that is sent over RSL, all AMR rates except the
highest one are trimmed. This was to ensure that the multirate
configuration IE only contains one codec rate per active set. Lets fix
that and generate a proper IE with threshold and hysteresis values.
- extend lchan_mr_config so that it can generate a full multirate
configuration IE
Change-Id: I7f9f8e8d9e2724cbe3ce2f3599bc0e5185fd8453
Related: OS#3529
Usually, conn->lchan is set to NULL before/upon releasing it. However, if the
lchan is still associated with a conn upon/after release, make sure the conn
realizes it has no lchan and sends a BSSMAP Clear Request to the MSC.
lchan_reset() is the last step before an lchan is fully unused. In there, make
sure to notify any conn that might still be associated, with
gscon_forget_lchan().
lchan_cleanup() does the same, but in fact this is only called when an lchan is
*deallocated*, but instead it usually merely goes to the UNUSED state.
It may make sense to call gscon_forget_lchan() sooner, e.g. when entering a
releasing state. This here nevertheless is a final safeguard.
Related: osmo-ttcn3-hacks If772dbbc5f9790d3f911465e1303dd0a99811154
Change-Id: I88337a18246c44ba48da64bb611a3cbb647a750e
Opposed to all other codecs that are common in GSM, AMR requires a codec
configuration that is expressed by a bitmask (S0 to S15) in the speech
codec list in the ASSIGNMENT REQUEST. Also the BSC acknowledges those
configuration in the ASSIGNMENT COMPLETE message.
At the moment osmo-bsc ignores all incoming configuration bits. The bits
in the ASSIGNMENT COMPLETE speech codec (choosen) field are hardcoded.
- Store the configuration bits while parsing the ASSIGNMENT COMPLETE
- Create an intersection with the configuration that is actually
supported by the BSS
- Return the resulting (chosen) configuration bits with the assignment
complete message.
- Use the (highest of the) agreed codec rates in RSL channel activation.
Change-Id: I2d8ded51b3eb4c003fe2da6f2d6f48d001b73737
Related: OS#3529
In case a given channel combination contains a CBCH, it replaces sub-slot 2
with a CBCH, i.e. we must not attempt to allocate the same for SDCCH.
On timeslot initialization, immediately place such an lchan FSM into new state
LCHAN_ST_CBCH, so that it never appears unused and never is picked during
lchan_select(). Also set lchan->type = GSM_LCHAN_CBCH.
Verified by configuring CBCH timeslots and watching 'show lchan summary'.
Immediately after RSL and OML are up, these pchan types show lchan 2 in state
CBCH:
BTS 0, TRX 0, Timeslot 0 CCCH+SDCCH4+CBCH, Lchan 2, Type CBCH, State CBCH - L1 MS Power: 0 dBm RXL-FULL-dl: -110 dBm RXL-FULL-ul: -110 dBm
BTS 0, TRX 0, Timeslot 1 SDCCH8+CBCH, Lchan 2, Type CBCH, State CBCH - L1 MS Power: 0 dBm RXL-FULL-dl: -110 dBm RXL-FULL-ul: -110 dBm
With a 'phys_chan_config ccch+sdcch4+cbch' and three phones simultaneously
requesting USSD, I see:
BTS 0, TRX 0, Timeslot 0 CCCH+SDCCH4+CBCH, Lchan 0, Type SDCCH, State ESTABLISHED - L1 MS Power: 14 dBm RXL-FULL-dl: -53 dBm RXL-FULL-ul: -47 dBm
BTS 0, TRX 0, Timeslot 0 CCCH+SDCCH4+CBCH, Lchan 1, Type SDCCH, State ESTABLISHED - L1 MS Power: 30 dBm RXL-FULL-dl: -47 dBm RXL-FULL-ul: -47 dBm
BTS 0, TRX 0, Timeslot 0 CCCH+SDCCH4+CBCH, Lchan 2, Type CBCH, State CBCH - L1 MS Power: 0 dBm RXL-FULL-dl: -110 dBm RXL-FULL-ul: -110 dBm
BTS 0, TRX 0, Timeslot 0 CCCH+SDCCH4+CBCH, Lchan 3, Type SDCCH, State ESTABLISHED - L1 MS Power: 16 dBm RXL-FULL-dl: -47 dBm RXL-FULL-ul: -47 dBm
With 'phys_chan_config SDCCH8+CBCH' and three phones simultaneously attaching,
I see:
BTS 0, TRX 0, Timeslot 1 SDCCH8+CBCH, Lchan 0, Type SDCCH, State WAIT_RLL_RTP_ESTABLISH - L1 MS Power: 0 dBm RXL-FULL-dl: -110 dBm RXL-FULL-ul: -110 dBm
BTS 0, TRX 0, Timeslot 1 SDCCH8+CBCH, Lchan 1, Type SDCCH, State WAIT_RLL_RTP_ESTABLISH - L1 MS Power: 0 dBm RXL-FULL-dl: -110 dBm RXL-FULL-ul: -110 dBm
BTS 0, TRX 0, Timeslot 1 SDCCH8+CBCH, Lchan 2, Type CBCH, State CBCH - L1 MS Power: 0 dBm RXL-FULL-dl: -110 dBm RXL-FULL-ul: -110 dBm
BTS 0, TRX 0, Timeslot 1 SDCCH8+CBCH, Lchan 3, Type SDCCH, State WAIT_RLL_RTP_ESTABLISH - L1 MS Power: 0 dBm RXL-FULL-dl: -110 dBm RXL-FULL-ul: -110 dBm
i.e. in all cases the CBCH lchan remains occupied and is not allocated as
SDCCH.
Detaching and re-attaching the BTS reliably brings back the CBCH state. Also
verified that changing the osmo-bsc config from telnet vty and dropping oml
followed by the BTS re-attaching brings back the CBCH state.
Change-Id: I2bafc5f696e818e38f8907ad0c8f38494df0623d
When activating an lchan, the power levels should be maximum and TA zero. Only
if a new lchan is assigned within the same cell does it make sense to take over
the previous power and TA levels.
In LCHAN_EV_ACTIVATE:
- Separate the code that copies previous encryption data. This should happen
regardless of whether we're staying in the same cell or not.
- For the power,TA levels, take over an old lchan's values only when it is
assigning a new lchan in the same cell.
Change-Id: I360b003398487fa6f934296ff03643c33ec61a35
Drop the todo comments about "for_conn->encr". I have intended that as an idea
to store encryption info in the conn instead of the lchan, which might make
sense, but there's no use in these comments.
Change-Id: I47e90062c784dd7919fff3115e2bee3314b30cd5
In lchan state UNUSED, on activating an lchan, we zero out the lchan->mr_ms_lv
and mr_bts_lv. However, in UNUSED's onenter function, we already called
lchan_reset(), clearing out the lchan completely.
Drop two lines of unnecessary code.
Change-Id: I8b38f222f1c8c822e8e5e776850dbc60e30e8b8d
The flag lchan->activate.concluded prevents entering the
lchan_on_fully_established()/lchan_on_activation_failure() more than once. So
far it was checked by callers, instead place in the functions themselves.
There is a potential functional change here, since during lchan_fail(), the
concluded flag was set only after entering lchan_on_activation_failure(). Now
it is already set at the start and prevents multiple re-entry beyond doubt.
This patch is not a result of an actual observed faulty behavior, just from
reading the code and seeing the slight loophole.
Change-Id: I0c906438b05442d66255203eb816453b7193a6d8
Early on during failure, log which state transition is intended after failure
handling.
If such state is already reached after failure handling, do not log "state
transition not permitted", but rather skip the state change and log "Already in
state X".
Change-Id: I81f53b38637823e62860cb773b7573bb5c21fdb0
lchan_fail_to() is a macro to preserve useful source file:line information in
logging. But a side effect is that its target state argument might evaluate
differently at the end of the macro, if, say, the fi->state has changed.
I hit such an instance on timeout of WAIT_RLL_RTP_ESTABLISH:
lchan_fsm_timer_cb() calls macro lchan_fail(), which calls
lchan_fail_to(lchan_fsm_on_error[fi->state]). Unlike for normal function
invocation, this argument changes as fi->state changes. Since releasing the
lchan_rtp_fsm already transitions the lchan fi into WAIT_RF_RELEASE_ACK, the
final state change of lchan_fail_to() suddenly evaluates to the broken state
instead of the intended WAIT_RF_RELEASE_ACK.
Early in lchan_fail_to(), store the argument's value as of macro invocation.
Change-Id: Id9bf4580a112ee5629f553a8bcb6b5b03b1c5f53
If a release event is being handled, ignore other ricocheting release events
until that release handling has concluded.
For example, if an lchan is regularly released, it signals the lchan RTP FSM to
release, which then calls back to say "RTP is released" on termination -- this
should not trigger other state changes than the initial release intends.
Change-Id: Iec41e006b6ab9d0f618d36925341f9536353e5d8
In various FSMs, some events may appear later or earlier without need of
action. Do not indicate these as 'ERROR' (event not permitted), but allow and
ignore them.
Debug-log about some of those.
From the old code, we've taken over the habit to change into
WAIT_BEFORE_RF_RELEASE even before SAPI[0] is released. Hence we may still
receive a SAPI[0] REL_IND in WAIT_BEFORE_RF_RELEASE. Don't show this as error
message, just silently accept it.
Change-Id: Ie320c7c6a1436184aaf2ec5a1843e04f4b3414ab
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
Neels Hofmeyr
Philipp Maier