This clarifies the different paths and uniforms them. Makes code far
easier to read and debug.
New improved verification already found some misehavior in some tests.
Change-Id: I7e4a88d6e004bbb7974595320ed73742162c7ad7
Move FSM internal state checks to its own file. Re-use the helper
function in the 2 places where same stuff is checked.
Change-Id: I9ded6e1c80e6cd7bcf6883bc2e853b6dafb33f7c
Make use of the separate GPRS counters added in previous patch
I0c0a1121b4ae5f031782e7e63a0c28eb0b6c8b42 to shorten
has_gprs_only_tb_attached.
Related: SYS#4878
Change-Id: I1dd7df2c740ea604f07c65bebcb7c0051aebf9ae
Add stats needed for performance measurements in
3GPP TS 52.402 § B.2.1.54-55.
Split m_num_tbfs to count GPRS and EGPRS TBFs separately. Move the code
that updates m_num_tbfs and sets the PDCH_OCCUPIED stats to a separate
function, as it's mostly the same in the TBF attach and detach.
Related: SYS#4878
Change-Id: I0c0a1121b4ae5f031782e7e63a0c28eb0b6c8b42
Count available PDCHs (3GPP TS 52.402 § B.2.1.38) as well as occupied
PDCHs (§ B.2.1.42-44).
Related: SYS#4878
Change-Id: I74760a68ee055510a79e80854ec7bf1521669119
When a PDCH TS becomes disabled (eg due to dyn TS being used for a
call), we are currently freeing all attached PDCHs in order to avoid
further use of it. However, pdch_free_all_tbf() was only freeing TBFs
attached to the PDCH, that is, TBFs having a valid TFI assigned.
There are some cases where temporary dummy TBFs are created which have
no TFI assigned, such as when creating an ImmAssReject. Let's take those
into account too, and make sure they are freed.
Related: OS#5226
Change-Id: Ibfe78448ebdedc8b049c80664711e166d910f9b7
There's no real use in having those 2 methods separately, and only adds
complexity. Let's merge it to have 1 TBF code path handling DL ACK/NACK.
Change-Id: I546d2e46bda96a2f551b28673464e57831c71828
The flag is only used to print some non interesting stuff, let's drop it
in order to simplify code. We can add later whatever we want in the new
shiny FSM.
Change-Id: I13f92f058c219f230d57b3c00b8ae1d187603813
The flag is only used to print some uninteresting stuff, let's drop it
in order to simplify code. We can add later whatever we want in the new
shiny FSM.
Change-Id: I20aa7f83cc4f32de129e64c74a91745b983a7b16
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
Go through all callers of as_dl_tbf() and as_ul_tbf(), and make sure
they can handle the possible NULL return value.
OS#5205 reports a NULL deref crash of osmo-pcu at pdch.cpp:525. The
immediate cause is that as_dl_tbf() may well return NULL, which this
caller does not handle and instead dereferences immediately.
This is a code path that apparently assumes that a DL-TBF should always
be present. The higher level cause for the NULL DL-TBF has not been
identified.
Related: OS#5205 SYS#5561
Change-Id: I8ce21be6836549b47a606c00b793d6f005964c5c
In existing previous code, pdch->ulc would be freed in
gprs_rlcmac_pdch::free_resources() when it became disabled as per PCUIF
info_ind (for instance, when a DYN TS is switched PDCH->SDCCH8).
However, pdch->ulc was so far only allocated during pdch_init, which is
only called during bts_alloc() time.
Hence, after first info_ind disabling it, if it became again enabled
(again by info_ind re-enabling it after SDCCH8 was not longer in use),
the pdch->ulc would be used again but it would point to freed memory.
Let's rearrange how/when resources are freed to make it more logical.
With this patch, pdch internal resources are freed upon ->disable(), and
re-allocated upon ->enable().
Change-Id: Id51f5f6a54ac9f24b784c17bc360ac38f5726fc7
If bts_ms_by_tlli() at the start of the function fails, ms could be
NULL. As a result "ms->nacc" access at the end of the function would
crash.
Solution:
In the function, we get the related expected TBF from pdch_ulc, and we only
continue if a TBF is found. Since tbf objects are always expected to
have a GprsMs, simply gather it from there.
Change-Id: I666ed5d157f42e74956fa49fc9eea85d27e63d44
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
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
During RELEASING state the TFI, USFs, etc. are still reserved and
assigned to the TBF, and hence the TBF may still use it.
If callers of this function rely on not taking TBFs under RELEASING
state, they should check that explicitly.
It still makes sense being to operate on RELEASING TBFs, since under
some circumstances the TBF may go under a previous state. See for
instance 3GPP TS 44.060 sec 8.1.1.3a.2:
"""
If N3101 reaches the value N3101max, the network shall stop sending
PACKET UPLINK ACK/NACK messages to the mobile station for that TBF
and shall start timer T3169 for the TBF. If an RLC/MAC block is received
from the TBF when timer T3169 is running, the network shall stop timer
T3169 and resume sending PACKET UPLINK ACK/NACK messages to the TBF.
When T3169 expires, the network may consider the TBF as released and
reuse the TFI value.
"""
Change-Id: Ibb471e727388512d42794d3faa26597e2545b852
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
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
This allows easily checking the initial reason to trigger the poll when
either it is received or times out.
Later on this reason can be transformed into an FSM event and sent to
the related FSM.
Related: OS#5020
Change-Id: Ie8fefd1f47ad674ce597a8065b15284088956bde
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
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
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
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
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: I17c28abf63b153448b533971ac5cf2e48daadea8
Use the fact that the MS must answer the RRBP of the Pkt Cell Change
Continue with a CTRL ACK to find out whether the message was received
successfuly or a retransmission is potentially required.
3GPP TS 44.060:
"""
When the mobile station receives the PACKET CELL CHANGE ORDER or
the PACKET CELL CHANGE CONTINUE message the mobile station shall
transmit a PACKET CONTROL ACKNOWLEDGMENT message in the specified
uplink radio block if a valid RRBP field is received as part of the
message; the mobile station may then switch to a new cell.
"""
Related: SYS#4909
Change-Id: I7cc28922e71699598da0ef6eb90136a47d3c002f
A new nacc_fsm is introduced per MS object, with its partner priv
structure struct nacc_fsm_ctx, which exists and is available in the MS
object only during the duration of the NACC procedure.
The NACC context is created on an MS whenever a Pkt Cell Change
Notification is received on Uplink RLCMAC, which asks for neighbor
information of a given ARFCN+BSIC.
First, the target ARFCN+BSIC needs to be translated into a CGI-PS
(RAC+CI) address. That's done by asking the BSC through the Neighbour
Resolution Service available in osmo-bsc using the CTRL interface.
Once the CGI-PS of the target cell is known, PCU starts a RIM RAN-INFO
request against the SGSN (which will route the request as needed), and
wait for a response containing the SI bits from the target cell.
After the SI are received, the scheduler is instructed to eventually
poll a TBF for the MS originating the CCN, so that we can send the SI
encapsulated into multiple Packet Neighbor Cell Data messages on the
downlink.
One all the SI bits are sent, the scheduler is instructed to send a
Packet Cell Change Continue message.
Once the message above has been sent, the FSM autodestroys itself.
Caches are also introduced in this patch which allows for re-using
recently known translations ARFCN+BSIC -> CGI-PS and CGI-PS -> SI_INFO
respectively.
Change-Id: Id35f40d05f3e081f32fddbf1fa34cb338db452ca
There's no real point in using C++ there, and using C++ makes the
compiler fail to use llist_head in multi-bts patches added later due to:
"""
'offsetof' within non-standard-layout type is conditionally-supported
"""
Change-Id: I8965b5cc5a713e64788b5b6aa183d3035341ddbb
There's no real use of C++ in that file, and it causes problems when
using llist_head entry macros in future patches adding initial support
for multiple BTS in PCU object, so let's move it to plain C.
Change-Id: Ic771a89fd78b5e66151a5384f0ff6a8895589466
Before, we used tho have a BTs object split into 2 parts, a C
gprs_rlcmac_bts struct and a C++ BTS struct, and "bts_data" naming was
used to distinguish them in variable names. Nowadays the struct is
finally combined into one, so there's no point in using this "bts_data"
terminology, we use always "bts".
Change-Id: I9852bf439292d1abc70711bea65698b21bde0ee8
Previous work on BTS class started to get stuff out of the C++ struct
into a C struct (BTS -> struct gprs_glcmac_bts) so that some parts of
it were accessible from C code. Doing so, however, ended up being messy
too, since all code needs to be switching from one object to another,
which actually refer to the same logical component.
Let's instead rejoin the structures and make sure the struct is
accessible and usable from both C and C++ code by rewriting all methods
to be C compatible and converting 3 allocated suboject as pointers.
This way BTS can internally still use those C++ objects while providing
a clean APi to both C and C++ code.
Change-Id: I7d12c896c5ded659ca9d3bff4cf3a3fc857db9dd
As we integrate osmo-pcu more and more with libosmocore features, it
becomes really hard to use them since libosmocore relies heavily on C
specific compilation features, which are not available in old C++
compilers (such as designated initializers for complex types in FSMs).
GprsMs is right now a quite simple object since initial design of
osmo-pcu made it optional and most of the logic was placed and stored
duplicated in TBF objects. However, that's changing as we introduce more
features, with the GprsMS class getting more weight. Hence, let's move
it now to be a C struct in order to be able to easily use libosmocore
features there, such as FSMs.
Some helper classes which GprsMs uses are also mostly move to C since
they are mostly structs with methods, so there's no point in having
duplicated APIs for C++ and C for such simple cases.
For some more complex classes, like (ul_,dl_)tbf, C API bindings are
added where needed so that GprsMs can use functionalitites from that
class. Most of those APIs can be kept afterwards and drop the C++ ones
since they provide no benefit in general.
Change-Id: I0b50e3367aaad9dcada76da97b438e452c8b230c
dequeue_paging() dequeues the first paging (at the start of the list).
If a paging request is dequeued but later it cannot be added to the
message being sent, it has to be re-added to the list for later
processing on next message. However, existing code was enqueueing it at
the end, which meant that paging request was delayed for no reason.
Change-Id: Iad8e7045267d56e32f42db0fbb8448b1b1185f05
There are some restrictions to have both GPRS-only and EGPRS MS attached
to the same MS:
* Any MS needs to be able to successfully decode a DL block at least
every 18 DL blocks (360 ms). That means a Dl block with CS1-4 must be
sent at least once during that time.
* Any MS needs to be able to decode USF targeting it. GPRS-only MS can
successfully decode USF from DL blocks using GMSK: CS1-4 and MCS1-4.
In this patch, if USF of a GPRS-only MS is selected, then all DL EGPRS
TBFs are discarded from data block selection. However, this logic can be
further improved later by still allowing selection of DL EGPRS TBFs and
then forcing construction of a DL EGPRS data block using MCS1-4.
Sources:
* 3GPP TS 03.64 version 8.12.0 "6.6.4.1.1.2 Multiplexing of GPRS and EGPRS MSs"
* 3GPP TS 05.08 version 8.23.0 "10.2.2 BTS output power"
Related: OS#4544
Change-Id: Ib4991c864eda6864533363443f76ae5d999532ae
Pau Espin
Oliver Smith
Neels Hofmeyr