Commit Graph

203 Commits

Author SHA1 Message Date
Pau Espin bd54205475 Optimize PAGING-CS PDCH set selection when target MS is known
Before this patch, when a PAGING-GS was received in PCU from SGSN, it
would always forward the paging request to all PDCHs in all TRXs of all
BTS (well, it did some heuristics to avoid sending it in some PDCHs
where onyl repeated TBFs would be listening).

The previous behavior, didn't make much sense in the case where the PCU
is asked to page an MS which it knows (ie in which PDCHs is listening
to). Hence, in that case it makes sense to simply send the paging
request on 1 PDCH where the MS is listening, instead of sending it in a
big set of different PDCHs.

This commit also splits the old get_paging_mi() helper which was
erroneously created to parseboth CS/PS-PAGING requesst, since they
actually use a different set of target subscriber information (for
instance, CS-PAGING provides optionally a TLLI, and one provides P-TMSI
while the other provides TMSI).

In this patch, the handling of CS paging request is split into 2 parts:
1- A new helper "struct paging_req_cs" is introduced, where incoming
CS-PAGING requests (from both SGSN over BSSGP and BTS/BSC over PCUIF)
are parsed and information stored. Then, from available information, it
tries to find a target MS if avaialable
2- bts_add_paging() is called from both BSSGP and PCUIF paths with the
helper struct and the target MS (NULL if not found). If MS exists,
paging is forwarding only on 1 PDCH that MS is attached to. If no MS
exists, then the old heursitics are used to forward the request to all
MS.

Change-Id: Iea46d5321a29d800813b1aa2bf4ce175ce45e2cf
2021-05-19 12:46:00 +02:00
Pau Espin 4b7a71f93f bts: constify arg in func bts_ms_store()
Change-Id: I4cc8c4fc075cdd07e689511df8f1c267e5360014
2021-04-30 17:42:25 +00:00
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 fecab50066 sysmo: fix wrong FN jumps in rx RA.ind
There's no need for setting the FN in RA.ind since we anyway already
receive a DATA.ind beforehand.
Furthermore, the applied delay of 5 in the call is not really used at
all.

Change-Id: I437f4f95d054aea96bec3b9343e495451020ff3c
2021-03-17 15:58:16 +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 702ebee751 Introduce init() APIs for PDCH and TRX objects
This will make it easier to keep object specific initializations in
expected place.

Change-Id: Idf1dbdf8bc0b1e16d86eeeffb1193fdf3a57d6ef
2021-03-12 07:40:11 +00:00
Pau Espin 9688dc9aca bts: Add new stats to detect TBF allocation failure reasons
This is specially useful to detect for instance if a cell is handling
too many users, ending up in TFI or USF exhaustions. This information
can be later in the future used to tune TBF allocation algorithm behavior
(either manually/statially through config file, or
automatically/dynamically in code based on some thresholds).

Related: OS#5042
Change-Id: I5402e937ff8d800684655e500ef8e5c867141dc3
2021-03-01 13:18:36 +01:00
Pau Espin 4e1c9adb67 bts: Count TBF TS allocation failure
Related: OS#2282
Change-Id: I0696bf77364bd31b96c00614a58ce66809683d1c
2021-02-25 17:49:59 +01:00
Pau Espin Pedrol fe8de457ac Use ALPHA value received in SI13 from PCUIF
The old VTY command is marked as deprecated and still overrides the use
in case it's used.

Related: SYS#5358
Depends: libosmocore.git Change-Id I74fb0a3afc1ac4aadbfc609b882d929401f790eb
Depends: osmo-bsc.git Change-Id I8b97ea11bad5fe05f2f634945b5703ee9abde81d
Change-Id: I46f2a955b157a409055fca7fb917dc4f75482426
2021-02-22 12:29:12 +00:00
Philipp Maier a58ec61514 gprs_bssgp_rim: add serving BSS NACC application
Answer an incoming RAN INFORMATION REQUEST RIM PDU with RAN INFORMATION
PDU that contains system information type 1, 3 and 13

Depends: osmo-bts I5138ab183793e7eee4dc494318d984e9f1f56932
Change-Id: Id72118120c14984d2fb1b918b41fac4868150d41
Related: SYS#5103
2021-02-02 21:57:09 +01:00
Pau Espin c0a250d17d Introduce NACC support
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
2021-01-29 12:59:30 +01:00
Pau Espin 2e6b60df45 bts: Store RAC+CI from info_ind
Having those values at hand will be needed later for RIM / NACC related
purposes.

Change-Id: Ia3596e9e81cd71443be2cc6f2450bb7f91d2667d
2021-01-20 15:00:38 +01:00
Pau Espin d1049dc8cc Allow multiple bts objects in PCU
This patch doesn't really tests whether osmo-pcu can work on a multi-bts
environment, but it prepares the data structures to be able to do so at
any later point in time.

Change-Id: I6b10913f46c19d438c4e250a436a7446694b725a
2021-01-20 12:36:21 +01:00
Pau Espin 906aafc9e2 Move tbf::free_all static methods to proper object files
Move each method to the object on which they operate, be it a trx or a
pdch ts.

Change-Id: Ida715cbf384431d37b2b192fbd7882957c93a4d1
2021-01-19 16:28:13 +01:00
Pau Espin a45aafd39c Get rid of bts singletons
There's no BTS single global object anymore, get rid of those APIs. Move
users to use "pcu->bts", which will evolve to a linked list in the
future.

Change-Id: I9cf762b0d3cb9e2cc3582727e07fa82c8e183ec5
2021-01-19 16:28:13 +01:00
Pau Espin 2182e627cd Unify BTS into a C usable structure
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
2021-01-19 16:28:10 +01:00
Pau Espin 793583ea21 Fix configuration mess of initial_cs/mcs between PCUIF and VTY
Both values (optionally) set (forced) by VTY and the values received
from PCUIF were stored in the same variable, meaning that for instance
the PCUIF values wouldn't really be used if someone applied eg "no cs"
during runtime.

This commit does something similar to what was already done for the
max_(m)cs fields. We store PCUIF values in one place and VTY ones in
another place, and then trigger a bts object internal process to find
out exactly which initial CS should it be using.

Change-Id: I80a6ba401f9c0c85bdf6e0cc99a9d2008d31e1b0
2021-01-18 11:57:14 +01:00
Pau Espin f473ec9d7a Move llc_* fields from BTS to PCU
Change-Id: Iffb916e53fdf99164ad07cd19e4b35a64136307e
2021-01-18 11:54:57 +01:00
Pau Espin 519d071131 Move ws_* fields from BTS to PCU
Change-Id: I997bc52f0d924c8f2a0b1d6cf23af98828ad4258
2021-01-18 11:54:57 +01:00
Pau Espin e891222920 Move fc_* fields from BTS to PCU
Change-Id: I816d49e732d0fc7a3c9aa1f0e9a83b83d25e6a32
2021-01-18 11:54:57 +01:00
Pau Espin 113fb419ec Move ns_dialect field from BTS to PCU
Change-Id: Iffb22b776b91f93d6d2a7ccfa47deeecc22c33f0
2021-01-18 11:54:57 +01:00
Pau Espin 54b159aab9 Move (m)cs_lqual_ranges fields from BTS to PCU
Change-Id: I39e2fc7e229851610d797c594d84902af6079411
2021-01-18 11:54:57 +01:00
Pau Espin ad79b857cd Move cs_downgrade_threshold field from BTS to PCU
Change-Id: I3e1c65eb3cccff565d5d84588bdce93a47909a0f
2021-01-18 11:54:57 +01:00
Pau Espin e8dcf64881 Move cs_adj* fields from BTS to PCU
Change-Id: I2b00a83279dccd4feeeeb95e34878c4405e7972c
2021-01-18 11:54:57 +01:00
Pau Espin 97296b299c Move dl_arq_type field from BTS to PCU
Change-Id: I0b82ab59edd58d60e5581c707dc49f58de0ba203
2021-01-18 11:54:53 +01:00
Pau Espin 05f9f59a67 Move dl_tbf_preemptive_retransmission field from BTS to PCU
Change-Id: I3ab32fcafe83f3ecb116a5b8a05f58f3fddc5451
2021-01-18 11:38:38 +01:00
Pau Espin a281495008 Move alpha,gamma fields from BTS to PCU
Change-Id: I2fdd9c8a7393157183fff64084bb10e2a3b1dc63
2021-01-18 11:38:38 +01:00
Pau Espin 03de898d19 Move force_two_phase field from BTS to PCU
Change-Id: I68a6e032f725cde87992b99f039c5280e912faf7
2021-01-18 10:37:05 +00:00
Pau Espin 924aaad4bc Move T_defs_pcu from BTS to PCU object
Change-Id: I0cac5c12dff2e90b52d00383a00b4b94a9603a0a
2021-01-18 10:37:05 +00:00
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 Pedrol da971ee502 Convert GprsMS and helpers classes to C
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
2021-01-05 10:34:25 +00:00
Alexander Couzens 5012e07685 ns2: follow ns2 dialect changes
NS2 introduce a ns dialect to differentiate
between the 4 possible dialects.

Related: OS#4472, OS#4890
Depends: libosmocore.git Ia118bb6f994845d84db09de7a94856f5ca573404
Change-Id: I16dc82c38eb75c2b9d1197640a955fec7df84efc
2020-12-16 12:50:50 +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 b47b137c66 Fix configuration of initial_(m)cs
Properly clip initial_(m)cs values to be lower-equal than maximum
configured.

Regarding initial_mcs, use values provided by BTS, which were not used
before.

Change-Id: Ifc6bc7c2734d1ae404adc2497afec5366e4f9e50
2020-11-04 21:39:43 +01:00
Pau Espin 87eec1fd74 Get rid of bts->egprs_enabled
BTS simply notifies the PCU about the supported MCS, and PCU is
responsible for providing correct data formatting supported for the BTS
and the target MS.

Related: OS#4544
Change-Id: Ifcf23771bd23afc64ca6fea38948f98f2d134ecb
2020-11-04 21:39:43 +01:00
Pau Espin 133fe4a852 tbf_ul: Allow non-egprs phones if EGPRS is enabled
We'll be able to still serve GPRS-only phones if EGPRS is enabled.

Related: OS#4544
Change-Id: I2e01b9d0de7506e0c0960342d73dba29187fe61f
2020-11-04 21:39:43 +01:00
Pau Espin 343ec9b9fd Take into account BTS supported (M)CS values when retrieving the maximum
Change-Id: I2d3a8bbae2f9887400ce56d2f8303ea30abaecfa
2020-11-04 21:39:42 +01:00
Pau Espin d87722d03c pcuif: Improve BTS-supported CS/MCS handling
Take into account the MCS values supported by the BTS. In osmo-bts,
in general all MCS are enabled if "mode egprs" is selected in BSC,
and none otherwise.

Change-Id: Ie8f0215ba17da1e545e98bec9325c02f1e8efaea
2020-11-04 21:39:42 +01:00
Pau Espin 4d1663594b bts: define egprs_enabled as bool
Change-Id: I66a8254ee392ad75226c58b7df5746f409463f0f
2020-10-29 11:34:17 +00:00
Vadim Yanitskiy d038361e95 struct gprs_rlcmac_bts: remove unused 'nsei' field
The code in gprs_nsvc_create_and_connect() stores NSEI there for
no reason, despite it's already stored in struct gprs_ns2_nse.

Change-Id: Ib30152a12384cf0448104a1ee1cfb949f4a27553
2020-10-10 05:05:33 +07:00
Alexander Couzens 290d9030e9 Use the new NS2 lib
Depends: Id7edb8feb96436ba170383fc62d43ceb16955d53 (libosmocore)
Depends: I2a9dcd14f4ad16211c0f6d98812ad4a13e910c2a (libosmocore)
Change-Id: Ib389925cf5c9f18951af6242c31ea70476218e9a
2020-10-06 16:38:38 +02:00
Neels Hofmeyr 59fc0bda6e paging: pass struct osmo_mobile_identity, not encoded IE bytes
In get_paging_mi(), before this, an encoded buffer of Mobile Identity bytes is
returned. Code paths following this repeatedly decode the Mobile Identity
bytes, e.g. for logging. Also, in get_paging_mi(), since the TMSI is read in
from a different encoding than a typical Mobile Identity IE, the TMSI was
manually encoded into a typical Mobile Identity IE. This is essentially a code
dup of osmo_mobile_identity_encode(). Stop this madness.

Instead, in get_paging_mi(), return a decoded struct osmo_mobile_identity. Code
paths after this use the struct osmo_mobile_identity directly without repeated
decoding.

At the point of finally needing an encoded Mobile Identity IE (in
Encoding::write_paging_request()), do a proper osmo_mobile_identity_encode().

Since this may return errors, add an rc check for the caller of
write_paging_request(), gprs_rlcmac_paging_request().

A side effect is stricter validation of the Mobile Identity passing through the
Paging code path. Before, invalid MI might have passed through unnoticed.

Change-Id: Iad845acb0096b75dc453105c9c16b2252879b4ca
2020-08-24 01:12:16 +00:00
Vadim Yanitskiy 07b6487c5a bts: add send_gsmtap_rach(), also send PTCCH/U over GSMTAP
Change-Id: I5cc4c3d2522215a31924121f83fcc2ac9ac6fe9c
2020-06-11 01:29:12 +07:00
Vadim Yanitskiy a0a0b7fb0e bts: refactor handling and parsing of RACH.ind
This patch is a set of tightly related changes:

  - group all RACH.ind parameters into struct 'rach_ind_params';
  - group Channel Request parameters into struct 'chan_req_params';
  - get rid of egprs_mslot_class_from_ra(), priority_from_ra(),
    and is_single_block(), introduce unified parse_rach_ind();
  - improve logging, get rid of redundant information.

This is needed for proper EGPRS Packet Channel Request handling.

Change-Id: I5fe7e0f51bf5c9eac073935cc4f4edd667c67c6e
Related: OS#1548
2020-06-03 12:49:40 +00:00
Pau Espin 0b0391ff66 gsmtap: Set signal level and SNR fields
lqual (containing C/I value) is passed instead of SNR, but let's have
that better than nothing.

Change-Id: Ibe9502d42c8bd1b984069e7fd805dde87ecbab0c
2020-05-20 14:20:56 +02:00
Pau Espin 2ae8337669 Get rid of class GprsCodingScheme
We have same kind of object splitted into two layers, in coding_scheme
and gprs_coding_scheme. Let's merge them together and get rid of the
class, which is not really useful because it's only a set of functions
operating on one enum value.

This change also fixes gcc 10.1.0 error about memseting a complex type
in rlc.h init().

Change-Id: Ie9ce2144ba9e8dbba9704d4e0000a2929e3e41df
2020-05-20 11:07:07 +00:00
Pau Espin 97e88fd35f bts: Drop specific functions to add values to stats
Change-Id: I877a9c9a35b6c94c3dd6b1ab3019bc57f6c8568a
2020-05-14 11:19:05 +00:00