Commit Graph

215 Commits

Author SHA1 Message Date
Pau Espin 8c4f978483 Drop logging last mas report before freeing TBF
There's no much use in logging it since anyway we are immediately
getting rid of it.

Change-Id: I9b712f720b5874886cc19d998fb8fcd0e618d590
2021-08-23 17:14:21 +02:00
Pau Espin cfb61d9536 Move T3169 and T3195 to tbf_fsm
Change-Id: I599f4e7e82b0a8c0f5cf633c2d8b1975435f0b60
2021-08-23 17:14:21 +02:00
Pau Espin 55f600b702 Move RELEASING tbf_state transition to tbf_fsm
PdchUlcTest output changes because the original state NULL is not
expected when transactioning to RELEASING upon MAX N310* being hit. In
any case, none of those events should happen in NULL state, but we
don't really care about TBF states there so we are fine with whatever
the state is.

Related: OS#2709
Change-Id: I516b8d989a0d705e5664f8aeaf7d108e0105aa16
2021-08-23 17:14:21 +02:00
Pau Espin efcb046ce1 Move WAIT_RELEASE tbf_state transition to tbf_fsm
While at it, method maybe_start_new_window is renamed to
rcvd_dl_final_ack to make more sense out of the code.

Related: OS#2709
Change-Id: Iebd650c1036ef2d5132789778be7117ce3391c01
2021-08-23 17:14:21 +02:00
Pau Espin c32c4a3648 Move FINISHED tbf_state transition to tbf_fsm
Related: OS#2709
Change-Id: I81f507e3a2821254f03364a58ead02333e63099f
2021-08-23 17:14:21 +02:00
Pau Espin 65bba93afa tests: tbf: Fix dl_tbf polled for data without being in FLOW state
Prior code was wrong, as in it did stuff diferent to what is expected
and actually done in osmo-pcu. In osmo-pcu code, the function is guarded
and only called in FLOW or FINISHED state by the scheduler.

Change-Id: If8029bee90adceee128ebb20c033756efd50e90e
2021-08-23 17:14:21 +02:00
Pau Espin 720e19e7f3 Move FLOW tbf_state transition to tbf_fsm.
Related: OS#2709
Change-Id: Ia8c7de759c195d09263fb1f083fbf6cfa3087f8d
2021-08-23 17:14:21 +02:00
Pau Espin 33e8007100 Move NULL and ASSIGN tbf_state transition to tbf_fsm
At some point later in time the state_flags will most probably be split
into different variables, one ending up in a different FSM. It is moved
so far to the exsiting FSM from the C++ class since it's easier to
access it from C and C++ code, and anyway that kind of information
belongs to the FSM.

Related: OS#2709
Change-Id: I3c62e9e83965cb28065338733f182863e54d7474
2021-08-23 17:14:21 +02:00
Pau Espin 88f34812df Revert "Revert "Stop abusing T3169""
This reverts commit 112c63e9b4.

Change-Id: Ic18674ccd38f81ddd46e1ec733159df350991899
2021-08-23 17:14:19 +02:00
Neels Hofmeyr 112c63e9b4 Revert "Stop abusing T3169"
This reverts commit 846fd248dc.

The commit introduced a leak of UL-TBF, which do not time out and
accumulate indefinitely, leading to out-of-memory for the running
osmo-pcu process.

A proper fix for the leak is pending on a development branch pespin/fsm,
but that branch is not yet ready for merging. Hence let's re-introduce
timer T3169 to avoid the OOM due to lingering UL-TBF.

Related: OS#5209
Change-Id: I99a7d2ddf68a76739ce2db1d6a44967dd97667b0
2021-08-15 17:46:53 +00:00
Pau Espin c6e911cf22 pdch: Log pdch_ulc reason upon rx of pkt ctrl ack
Change-Id: I7c7a421b1e9189e2814e9a28698d66655fc9ba60
2021-06-07 18:16:55 +02:00
Pau Espin dc2aaac29f tbf: Move existing tbf_state implementation to osmo_fsm
This is only an initial implementation, where all state changes are
still done outside the FSM itself.
The idea is to do the move in several commits so that they can be
digested better in logical steps and avoid major break up.

Related: OS#2709
Change-Id: I6bb4baea2dee191ba5bbcbec2ea9dcf681aa1237
2021-05-19 12:50:25 +02:00
Pau Espin 632542348a sched: Clean up helper function and improve logging
Change-Id: I8c19d0924e73c324a36ea038cab7cc4e096b866b
2021-05-12 14:23:59 +02:00
Pau Espin 4b6f0bfe69 Implement T3141
Related: OS#1940
Change-Id: I154984b835b2b436b1ebe4631a8afcebb7338c65
2021-05-11 11:32:44 +02:00
Pau Espin 20271c421c Split ul_tbf alloc on CCCH into new function
This allows more easily finding when this specific scenario happens, and
can easily be compared against the PACCH one.

Change-Id: I609792a40fda2a798ca71a0e9f5639d0a0f011d7
2021-05-11 11:32:44 +02:00
Pau Espin 393484a5d0 Simplify helper function tbf_select_slot_set()
Store direction check to simplify the code.
Get rid of 2-step LOGP to avoid multi-row logs in gsmtap log.

Change-Id: Ia2e061da82ddce564b2d768d8ade1672c22934e2
2021-05-10 11:21:52 +02:00
Pau Espin 2ab840a1fa Make WaitIndication T3172 configurable
Tbftest expectatins need to change because 5000/20 = 250 < 255, hence
the message is now sent as units of 20ms instead of seconds.

Related: OS#3928
Change-Id: I48b34b94b1a5dfb046a3a6cf8a0d944a7c9b6754
2021-04-26 17:53:09 +02:00
Pau Espin 54742f287c ul_tbf: Clean up handle_tbf_reject()
Document the function, make it look similar to usual TBF creation path
tbf_alloc_ul()->tbf_alloc_ul_tbf->tbf::setup(), which it mimics with
some differences.
Get rid of unneeded stuff like creating MS and settings its TLLI (that's
already done in only caller of the function). There's no need for
calling update_ms() either.

Change-Id: I61df2e4f0f0df1f8db941741a2d35a2319252c5e
2021-04-26 17:19:07 +02:00
Pau Espin 846fd248dc Stop abusing T3169
Now that we finally handle N3101 and N3103 correctly, we can fix abuse
of T3169 we were doing to make sure TBFs were freed.

According to 3GPP TS 44.060, T3169 should be armed:
* N3101_MAX reached
* N3103_MAX reached

Furthermore, when T3169 is enabled, the tbf should be in state
RELEASING so that its USF is not used.

See full description: https://osmocom.org/issues/5033#note-2

Related: OS#5033
Change-Id: I2cec531e2633281b88f69ba065c0105580c81076
2021-04-26 11:20:19 +02:00
Pau Espin 434799720c pdch: rcv_resource_request: Improve robustness
Use recently added PDCH UL Controller to verify expectancies.

Test test_packet_access_rej_prr is rewritten since it didn't make sense
as it was before, since it relied on osmo-pcu not checking stuff
properly to trigger the reject. The RACH requests are changed to
allocate 8 SBAs (maximum of 7 concurrent USFs). Allocating the SBA
doesn't reserve a USF, that happens at PKT RESOURCE REQUEST, hence we
end up exhausting resources there and triggering the REJECT at that
point.
Previous version of the patch allocated TBFs directly through RACH req,
and then submitted an extra PKT RESOURCE REQUEST which PCU didn't expect
to trigger the reject.

Change-Id: I157e72160317340ee7742c78c62a25d3d98fc01e
2021-04-22 20:28:40 +02:00
Pau Espin 58046e45d1 tbf: Get rid of attribute poll_fn
That field is not needed anymore, and it works only under the assumption
that only 1 poll request can be active at a time per TBF, which is not
true.

Change-Id: I63a34a702f028b871530fb7caeb13e8ea1cc78ac
2021-03-31 17:39:50 +02:00
Pau Espin 2c0931cedc Get rid of param 'poll' with constant value
Value 'false' is always passed by all callers of the function, so
there's no need to pass it. Furthermore, since it's false, there's no
need to access poll_fn since RRBP will always be invalid.

Change-Id: Ia48ce2a021865e76e813dedb22aca9c2522c5693
2021-03-31 17:39:50 +02:00
Pau Espin 127e7392f6 tbf: get rid of poll_state completely
The poll_state logic was part of previous implementation (prior to pdch
ul controller) where the ssumption was that TBF could only had 1 POLL
request in transit, which is really not true. With current
infrastructure we don't need this state tracking at all.

Change-Id: Ie5b807ccd38aa736ae11b3310ca61ad0156ca4d4
2021-03-31 17:39:50 +02:00
Pau Espin 42445ea944 tbf: Allow multiple concurrent polls
There's no good reason to allow only for 1 concurrent POLL requested to
a TBF, it was onyl done this was as an implementation limitation factor.
It can well happen that several multiple POLLs may be in transit at the
same time, eg to get DL ACK/NACK as well as to get a CTRL ACK for a Pkt
Cell Change Continue (NACC).

Change-Id: Ic4080db684a4626cae90dd574d123081981284ca
2021-03-31 17:39:50 +02:00
Pau Espin ed066b5328 tbf: Get rid of unneeded poll_scheduled()
This API is not really needed anymore, since anyway it works under the
assumption there can only be 1 POLL in transit per TBF, which isn't
necessarily true.

Change-Id: I875f51cade95faeb2d79dcebfead4c83e23a731b
2021-03-31 17:39:50 +02:00
Pau Espin 50a1ede693 pdch_ulc: Support picking RRBP other than N+13
Current algo always tries to sched RRBP the soonest possible.

Related: OS#5020
Change-Id: Ic6ddeea70e1f914cf423d0daab8fc492d0c992e2
2021-03-31 17:39:50 +02:00
Pau Espin 0b998b15da Properly implement N3101
N3101 is incremented by unanswered USF requests, not from unanswered
POLLs.

Related: OS#5033
Change-Id: I1a55bdd39db8843976915b9f74fadb0942298413
2021-03-24 17:16:29 +01:00
Pau Espin c1f38c7f0b Track scheduled UL blocks through USF
This way PCU can now detect whether scheduled UL blocks through USF
were never received. This allows in a follow-up patch to start
increasing N3101 properly.

Related: OS#5033
Change-Id: Ia99c9edad6e5bd837e9baeb4fb2683b227887957
2021-03-24 17:14:19 +01:00
Pau Espin 3a42d17b14 bts: Detect FN jumps
Change-Id: I29fb27981597edc69abb976049ba41aa840488cb
2021-03-15 19:34:35 +01:00
Pau Espin 99360a304f Replace PollController with newly added PDCH UL Controller
TbfTest is updated to submit empty blocks to have somehow meaningful
output (at least as meaningful test results as before, not much). That's
because we must update bts->curr_fn to have polls expire.

Related: OS#5020
Change-Id: I683ca738ce5a133c49c36a1d94439a942d64a831
2021-03-15 19:32:36 +01:00
Pau Espin 15c58ace75 Add new PDCH UL Controller, drop SBAllocator class
Right now we handle different types of UL allocations in different
classes like PollAllocator and SBAllocator, and they usually don't take
into account the other one in most cases. Furthermore, those objects are
usually per-BTS object, instead of per PDCH object.

This is a first step towards having a unified per-PDCH controller which
takes care of controlling what is scheduled and hence expected on the
uplink. Each PDCH has a UL Controller which keeps track of all reserved
uplink frame, be it SB, RRBP poll or USF assigned, all under the same
API.

As a first step, only the SBA part is fully implemented and used (being
it the easiest part to replace); TBF poll+usf will come in follow-up
patches later on. As a result, the SBAllocator per-BTS class dissappears
but some of its code is refactored/reused to provide more features to the
gprs_rlcmac_sba object, which is also further integrated into the new UL
Controller.

Related: OS#5020
Change-Id: I84b24beea4a1aa2c1528f41435f77bd16df2b947
2021-03-15 19:32:26 +01:00
Pau Espin 68bfdff3f0 pdch: Log FN when decoding UL Ctrl block
Change-Id: I5a44ebf49f7489211a77607052db6d9731f38704
2021-03-12 07:40:11 +00:00
Pau Espin 30617115ba Track TDMA clock with DATA.ind instead of TIME.ind
Since recently (see Depends below), BTS side submits DATA.ind with len=0
to announce nothing was received on that UL block FN. This will allow
osmo-pcu track time more accurately, and use this information to quickly
find out if a UL block was expected as requested by RRBP or USF poll and
increment counters such as N3101 (finally being able to properly
implement timers such as T3619).

Depends: osmo-bts.git Change-Id I343c7a721dab72411edbca816c8864926bc329fb
Related: OS#5020

Change-Id: Ibc495173119465e74f726ddc36e312334e6dc0fd
2021-03-12 07:40:11 +00:00
Pau Espin 58fdc54a7f tbf: Log N310* counter increments
Change-Id: Iacd2fb894b4f2a9aade7e66aa40969fea031c3b2
2021-03-04 14:11:23 +01:00
Pau Espin 2ad15d51fa sched: sched_select_downlink(): Clean up param list and improve logging
Passing TRX and TS is redundant since the info is contained in pdch
object.

Change-Id: I1b154d82c4a3e09f7fe7ef771de2abca0160cc7b
2021-03-03 20:52:26 +01:00
Pau Espin 3973eb5fe8 sched: sched_select_ctrl_msg(): Clean up param list and improve logging
Passing TRX and TS is redundant since the info is contained in pdch
object.

Change-Id: Ic3ec7547cae2ddd0f9c33b82e15ec83cd941e6c8
2021-03-03 20:47:09 +01:00
Pau Espin 11f01105a0 gprs_ms: Use standarized logging on more messages
Change-Id: If7f471f4932c2347cd857cd59f761a36d9e735d1
2021-03-03 20:37:38 +01:00
Pau Espin 4fe090146f ms: clarify delayed MS release process related code and logging
Change-Id: Ieaea6ab07b4b2822bcf394f2d0e9298b9f3c5854
2021-03-03 20:28:51 +01:00
Pau Espin Pedrol cf6c71263f tbf_dl: fix FBI not set upon X2031 = 0
If Idle TBF timer (X2031) is set to 0, it means the TBF release is
immediately started once all queued data has been scheduled. In that
case, we must set FBI=1 (by setting cv=0) and move to FINISH state.

This used to work over the usual path where X2031 != 0, because release
start will alays happen at a later sched poll time where a dummy LLC
frame is sent and FBI set accordingly.

Change-Id: Ib20602936ae084c413f6bfe14eea33b602020be0
2021-03-02 18:25:33 +01:00
Pau Espin Pedrol 8afc6bad80 tbf_dl: Fix m_last_dl_drained_fn not set under some conditions
Old commit getting rid of LLC UI dummy and updating create_new_bsn()
function introduced a bug by not moving update of value m_last_dl_drained_fn
prior to a new break introduced.
As a result, the value is not updated in the case LLC queue becomes
drained but last few bytes are drained at exactly that moment.
Furthermore, then the IDLE tbf timer (X2031, keep_open())) returns always
true since according to it the drain never happened.

The impact of the bug is basically delaying a bit more than expected the
time the TBF stays in IDLE state with the TBF release process yet
to be started.

Related: OS#4849
Fixes: 7d0f9a0ec3
Change-Id: I7420aeffda3500bcdc990291e4a56511af433ff9
2021-03-02 18:24:46 +01:00
Pau Espin Pedrol 5b9d0bb8e5 tbf: log keep_open condition status
Change-Id: I069e84926aaa8f13b23c3ea4083b4c68dbc6cff2
2021-03-02 13:13:52 +01:00
Pau Espin 36177c6b58 tbf: Improve logging when TBF being allocated or no TBF avail
Change-Id: I68491fe2c643262e35b4d4f1ecac34afcf61848f
2021-02-26 11:50:15 +01:00
Pau Espin 95e2266832 pdch: Standarize and improve logging
Change-Id: I1686a72eb9f9014ed3365376bc43d59d60bee8a5
2021-02-26 11:36:55 +01:00
Pau Espin 7c9a4a41bc tbf: Log timeslot allocation failure
Change-Id: I48fc1eac37eeb74649bfc0888e06afc0079a58f8
2021-02-25 17:21:10 +01:00
Pau Espin ac3fd12026 Split PCU global PCU object from BTS object
Currently the BTS object (and gprs_rlcmac_bts struct) are used to hold
both PCU global fields and BTS specific fields, all mangled together.
The BTS is even accessed in lots of places by means of a singleton.

This patch introduces a new struct gprs_pcu object aimed at holding all
global state, and several fields are already moved from BTS to it. The
new object can be accessed as global variable "the_pcu", reusing and
including an already exisitng "the_pcu" global variable only used for
bssgp related purposes so far.

This is only a first step towards having a complete split global pcu and
BTS, some fields are still kept in BTS and will be moved over follow-up
smaller patches in the future (since this patch is already quite big).
So far, the code still only supports one BTS, which can be accessed
using the_pcu->bts. In the future that field will be replaced with a
list, and the BTS singletons will be removed.

The cur_fn output changes in TbfTest are actually a side effect fix,
since the singleton main_bts() now points internally to the_pcu->bts,
hence the same we allocate and assign in the test. Beforehand, "the_bts"
was allocated in the stack while main_bts() still returned an unrelated
singleton BTS object instance.

Related: OS#4935
Change-Id: I88e3c6471b80245ce3798223f1a61190f14aa840
2021-01-18 10:37:05 +00:00
Pau Espin c2d3625bf6 tbf: remove 'software error' logs from tbf_free
It is expected that the tbf object is freed at any moment in time, for
instance if osmo-pcu drops PCUIF connection with osmo-bts. I couldn't
find any reason why it would e dangerous to free the tbf, so let's
remove this message.

related: OS#4779
Change-Id: I4ab5ccaa5bf6257b18d8fd5ba06baab083821817
2021-01-11 19:17:05 +01:00
Pau Espin 7d0f9a0ec3 Dl TBF: Get rid of LLC UI dummy blocks following other data
According to:
* 3GPP TS 44.060 version 16.0.0 "9.3.1a Delayed release of downlink Temporary Block Flow"
* 3GPP TS 44.064 version 16.0.0 "6.4.2.2 Unconfirmed Information (UI) Dummy command"

LLC UI Dummy frames are to be used when there no more data to send, only
in order to delay the release of a TBF. Hence, while not incorrect per
se, makes no sense to send those LLC UI Dummy frames inserted into
rlcmac blocks which already contain other LLC frames, since the MS in
that case is already being kept active.
It only makes sense to send those LLC UI Dummy frames when we have
nothing else to send, that is, alone inside a RLCMAC block without other
LLC frames.

Related: OS#4849
Change-Id: Ifae1a7b2b3dfad8df19585063088ba0df2749c8f
2020-12-01 15:57:37 +01:00
Pau Espin 022f9e56e5 Implement downgrade to DL MCS1-4 when USF for GPRS_only MS
In previous status, if USF for GPRS-only MS was selected, then EGPRS
TBFs were skipped and either a GPRS TBF was selected or a Dummy Block
was sent. That means the behavior was unfair towards EGPRS TBFs, because
sometimes they were skipped in favor of GPRS ones.
This patch imporves the situation in the above mentioned USF scenario, by
first, under specific conditions, allowing selection of an EGPRS TBF and
then forcing it to transmit in EGPRS-GMSK (MCS1-4) so that the
USF-targeted MS can still decode the USF, while at the same time
providing more fairness by allowing the EGPRS TBF to transmit data.

The specific conditions mentioned above are, mainly, related to the fact
that once a DL data block has been sent, and hence a BSN was assigned to
it, it cannot be retransmitted later using another MCS, since lower
MCS1-4 wouldn't be able to contain higher MCS RLC payload.

The set of conditions could be expanded in the future by also selecting
the EGPRS TBF if retransmition is required and the block to be
retransmitted was originally transmitted as MCS1-4.

Related: OS#4544
Change-Id: I9af23e175435fe9ae7b0e4119ad52fcd4707b9ca
2020-12-01 11:56:01 +00:00
Vadim Yanitskiy cb98894eb1 TLLI 0x00000000 is a valid TLLI, use 0xffffffff instead
The assumption that TLLI 0x00000000 is invalid and can be used
as the initializer is wrong.  Similar to TMSI, 0x00000000 is a
perfectly valid value, while 0xffffffff is reserved - use it.

According to 3GPP TS 23.003, section 2.4, a TMSI/P-TMSI with
all 32 bits equal to 1 is special and shall not be allocated by
the network.  The reason is that it must be stored on the SIM,
where 'ff'O represents the erased state.  According to section
2.6 of the same document, a local/foreign TLLI is derived from
P-TMSI, so the same rule applies to TLLI.

I manually checked and corrected all occurances of 'tlli' in the
code.  The test expectations have been adjusted with this command:

  $ find tests/ -name "*.err" | xargs sed -i "s/0x00000000/0xffffffff/g"

so there should be no behavior change.  The only exception is
the 'TypesTest', where TLLI 0xffffffff is being encoded and
expected in the hexdump, so I regenerated the test output.

Change-Id: Ie89fab75ecc1d8b5e238d3ff214ea7ac830b68b5
Related: OS#4844
2020-11-10 17:06:39 +00:00
Pau Espin 569f0d27c7 tbf_dl: Don't fake EGPRS MS class when no related info is available
For instance if PCU received DL data to be sent to an MS from an SGSN,
and the MS is not currently cached in the PCU (because there's no TBF
active for it), it will page it and transmit the DL data to it.
The SGSN is capable of sending (EGPRS) MS Class information in that same
DL data message, so it's the one responsible for providing that
information if not available at the PCU.
In the PCU if we don't have information about that MS and SGSN didn't
provide us information about it, we cannot assume the MS is going to be
EGPRS capable and even less expecting a specific EGPRS MS class.
So let's drop this code.

Related: OS#4544
Change-Id: Icce66cadb51af25ae0c3b3719940eccb548fe33b
2020-11-04 21:39:42 +01:00