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
NS2 introduce a ns dialect to differentiate
between the 4 possible dialects.
Related: OS#4472, OS#4890
Depends: libosmocore.git Ia118bb6f994845d84db09de7a94856f5ca573404
Change-Id: I16dc82c38eb75c2b9d1197640a955fec7df84efc
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
This VTY command was added due to EGPRS being introduced later as an
experimental feature. It's no longer needed and causes more problems
than goodness (since people sometimes forgets to enable it).
Let's rather simply enable EGPRS support based on what BTS/BSC requests
over PCUIF.
Related: OS#4544
Change-Id: Ic80970a136361584da9c912252a07e7c3c9d85d0
Since I2b32b4fe20732728db6e9cdac7e484d96ab86dc5, go_parent_cb()
is completely optional. It no longer has the task to determine
the correct parent node. The is_config_node() callback is no
longer needed too. Get rid of them.
Since Ic5e69a396df659933fd4d50298b9925e837a6861 we depend on 1.3.0.
Change-Id: Id7ce8c4e1ac43747ad40a06d01433c366da07b42
Others projects don't contain a dash in there, and it seems to cause
problems with TTCN3 VTY expectations.
Change-Id: I3430abb5fc622dec293457466e760de95fa3a05c
Some are used to control (M)CS values for downlink while some do it for
uplink. Let's make clear which one is used for what. Take the chance to
document the fields a bit better than they were.
Some more information about the origin of cs_downgrade_threshold can be
found in the commit introducing it: 70b96aa232.
Related: OS#4286
Change-Id: I4e890e924b094a1937fbd3794de96704cf0421a8
For a long time the VTY command to show all active TBFs was broken.
The TBF filtering (by allocation origin) logic allows one to show
TBFs allocated on CCCH, PACCH, or on both of them. In the latter
case we have been checking whether a TBF was allocated on both
logical channels at the same time.
Let's fix this by passing a flag-mask instead of boolean arguments.
To be able to use GPRS_RLCMAC_FLAG_* definitions from "tbf.h", let's
exclude them from "#ifdef __cplusplus ... #endif" block.
Change-Id: I1c9f401368af880a97d32905c4cce0da481ffc21
This commit would also remove the option from config_write_pcu() since
it's automatically filled in by osmo_tdef, but there was actually a bug
because that param was never printed when saving the config...
Change-Id: Id8e70b0f44ef2f7e20ecdb3fd8ca93ae2a05b9a3
This will allow for configuration of some of the timers by the user,
and allow him to inspect current values being used.
It will be also useful for TTCN3 tests which may want to test some of
the timers without having to wait for lots of time.
Timers are splitted into 2 groups: BTS controlled ones and PCU controlled
ones. The BTS controlled ones are read-only by the user (hence no
"timer" VTY command is provided to change them).
TbfTest.err output changes due to timers being set up correctly as a
consequence of changes. Other application such as pcu_emu.cpp and
pcu_main.cpp had to previosuly set the initial values by hand (and did
so), but apparently TbfTest.c was missing that part, which is now fixed
for free.
Depends: libosmocore.git Id56a1226d724a374f04231df85fe5b49ffd2c43c
Change-Id: I5cfb9ef01706124be262d4536617b9edb4601dd5
Since [1], OsmoPCU already starts to retransmit downlink blocks before
the MS has had a chance to receive them and/or send the related
acknowledgement in uplink. Make this optional with the new VTY option
"no dl-tbf-preemptive-retransmission".
[1] e25b5b91f6 ("tbf: Only create dummy frames if necessary")
Related: OS#2408
Change-Id: Id08aed513d4033aa0d4324c6ce07cbb2852f2f92
Since March 15th 2017, libosmocore API logging_vty_add_cmds() had its
parameter removed (c65c5b4ea075ef6cef11fff9442ae0b15c1d6af7). However,
definition in C file doesn't contain "(void)", which means number of
parameters is undefined and thus compiler doesn't complain. Let's remove
parameters from all callers before enforcing "(void)" on it.
API osmo_stats_vty_add_cmds never had a param list but has seem problem
(no "void"), so some users decided to pass a parameter to it.
Related: OS#4138
Change-Id: Ic1ac815eafab49577ff883a5d700ecca5936d216
This change add support for the recently-introduced GPRS Gb interface
auto-configuration using the NS IP Sub-Network Service (SNS) procedures.
It requires a Change-Id I84786c3b43a8ae34ef3b3ba84b33c90042d234ea of
libosmocore.
Related: OS#3372
Depends: I84786c3b43a8ae34ef3b3ba84b33c90042d234ea (libosmcore)
Change-Id: I256b40ac592d3b6e75dd581bf7b9512f69b11e83
The PDCH class and corresponding functions are rather self-contained and
independent from BTS implementation. Let's move them into separate file
to make bts.cpp more manageable. As additional benefit it allow us to
somewhat untangle all the different cross-dependent includes.
Change-Id: Ie05e25361e6741a81b024679f9675c98d4923683
Related: OS#1539
vty_install_default() and install_default() will soon be deprecated.
Depends: I5021c64a787b63314e0f2f1cba0b8fc7bff4f09b
Change-Id: I6c9f928f4a4d7fd6bf37c64a64ee5d843ad5bb7a
We have seen that UL MCS5- MCS9 link adaptation has not been implemented in current PCU implementation.
If the MS slowly moves far away from the BTS, the UL MCS will always stick at MCS9 no matter UL link quality values leading to poor data service experience.
The UL MCS is expected to adapt from MCS9 -> MCSx due to bad UL quality.
Below PCU traces indicate that UL MCS is quickly increasing to MCS9 (max MCS 9 was used in this test) and it never changes to other UL MCS due zero thresholds.
<0004> gprs_ms.cpp:670 MS (IMSI ): Link quality 23dB (23dB) left window [0, 0], modifying uplink CS level: MCS-6 -> MCS-7
<0004> gprs_ms.cpp:670 MS (IMSI 000): Link quality 23dB (23dB) left window [0, 0], modifying uplink CS level: MCS-7 -> MCS-8
<0004> gprs_ms.cpp:670 MS (IMSI 000): Link quality 23dB (23dB) left window [0, 0], modifying uplink CS level: MCS-8 -> MCS-9
Change-Id: I9272c337ad6399da4a47cc6e2736e25f24e099d8
osmo-bts already supports configuring a different path for the bts<->pcu
socket by using the 'pcu-socket' config field.
Change-Id: I9b3e1171da467519750b201849ec892a1e318129
When looking at GSMTAP output so far, one is easily overwhelmed by way
too much information being presented. A lot of is consists of DUMMY
frames, which are probably of lowest interest, ever.
A concept similar to the "gsmtap-sapi" of OsmoBTS is introduced, by
which the user can configure which particular categories (uplink or
downlink control or data, gprs or egprs, ...) he actually wants to
see in his logs.
Change-Id: I297183690e98a7234dfc1608c18847d8981306e4
Modify the EGPRS DL TBF flow to support Split block during
Retx. This patch will also Upgrade the test suite with test cases
to validate the EGPRS Downlink SPB for Retransmission
Scenarios like MCS6->MCS3, MCS4->MCS1, MCS5->MCS2, MCS9->MCS3
MCS7->MCS2, MCS8->MCS3 have been simulated and Integration tested
in NuRAN 1.0 hardware thoroughly.
Change-Id: I242afdd8ae7622dec8593b26382ad66bad5b9516
This warning is not valid since the PCU is not failing when EGPRS is
activated. So removing this trace
Change-Id: I62278f998adc691b9a3563ac2a46d756e7bfb66c
This adds the following VTY command (config-pcu node):
- mcs <1-9> sets initial DL and UL MCS to the same value
- mcs <1-9> <1-9> sets initial DL and UL MCS separately
- no mcs sets the default values
Sponsored-by: On-Waves ehf
Currently the window size is fixed to 64 even for EGPRS.
Support dynamic window sizes depending on the number of PDCH. The
WS can be set to b + f * N_PDCH. If the result is not valid according
to TS 44.060, Table 9.1.9.2.1, the value will be corrected to use the
next lower valid value (or 64).
The following VTY commands are added (config-pcu node):
window-size <0-1024> set base (b) value and leave f unchanged
window-size <0-1024> <0-256> set base (b) and factor (f)
Sponsored-by: On-Waves ehf
Currently the plain 'egprs' command enables EGPRS but doesn't prevent
phones from being served in GPRS mode if they do not support EGPRS.
This involves complex frame allocation implementations in dynamic
mode, especially if 8PSK is being used. This is due to the inability
of non-EGPRS phone to decode 8PSK USF and ES/P altogether. Since
polling has a higher priority than USF, collisions will have to be
prevented by the PCU by never using an GPRS USF if it refers to a FN
that is already being used for polling.
This commit just disables mixed usage by ignoring GPRS-only request
if EGPRS is enabled.
The following VTY command (config-pcu node) is changed:
egprs -> egprs only
Sponsored-by: On-Waves ehf
This sets the maximum MCS encoding used for EGPRS RLC data blocks
in either direction.
The following VTY command are added to node config-pcu:
- mcs max <1-9> set maximum for both, uplink and downlink
- mcs max <1-9> <1-9> set maximum for downlink and uplink (in that
order)
- no mcs max do not limit
Note that using a value of 4 or below for each direction implies
that a GMSK-only TBF may be assumed, which for instance would allow
the use of the GPRS MS class instead of the possibly more restrictive
EGPRS MS class.
Sponsored-by: On-Waves ehf
LListHead does basically the same like llist_pods, but more C++ish
and with type safety.
This commit turns the former list field of gprs_rlcmac_tbf into a
private field, provides accessors, moves the related code from
pcu_vty.c to pcu_vty_functions.cpp, and removes the llist_pods
type and related code.
Sponsored-by: On-Waves ehf
Enable the TBF to use EGPRS if the bts->egprs_enabled config variable
has been set via the VTY "egprs" command and if the MS has signaled a
EGPRS multislot class.
Tell the MS to use EGPRS if the condition above holds.
Note that this will cause the MS to use EGPRS RLC block formats for
further messages which are not yet understood by the PCU.
Sponsored-by: On-Waves ehf
Add a global config flag to enable the use EDGE/EGPRS.
The following VTY commands are added to node config-pcu:
- egprs Enables EGPRS
- no egprs Disable EGPRS
Note that enabling EGPRS is experimental and will most likely break
packet transmission until a minimal required set of EGPRS
functionality is implemented.
Sponsored-by: On-Waves ehf
This commit fixes the go_parent_cb API according to libosmocore's
commit of the same name.
Fixes:
pcu_vty.c:799:2: warning: initialization from incompatible pointer
type [enabled by default]
.go_parent_cb = pcu_vty_go_parent,
Sponsored-by: On-Waves ehf
Currently packets are only dropped if they have reached their maximum
life time. This leads to LLC queues being constantly filled under
load, increasing the latency up to the maximum life time. This kind
of bufferbloat hinders TCP's congestion avoidance algorithms. To keep
the queues short, the CoDel active queue management algorithm can be
used.
This commit changes to llc_dequeue method to apply the CoDel
algorithm to selectively drop LLC frames before they passed to the
TBF layer to be encoded in BSNs. This feature is currently disabled
by default.
The CoDel state is managed per MS since the LLC queues are also kept
in the MS objects.
Note that there is still some buffering in the TBF objects, in the
worst case (CS4) 3.5kByte + LLC-MTU octets are stored there. The
resulting additional packet delay is not (yet) taken into account for
CoDel.
Also note that configuration changes are applied to new MS objects
only.
The following VTY commands are added to the 'pcu' node:
- queue codel activates CoDel, the interval is selected by
the implementation
- queue codel interval <1-1000>
activates CoDel with a fixed interval given
in centiseconds (10ms-10s)
- no queue codel deactivates CoDel
Which interval value to use is still an open issue. For high speed
links (e.g. Ethernet), CoDel suggests 100ms. For slower links, the
expected RTT is recommended. The current implementation uses a
default value of 2000ms.
Measurements:
Note that the following measurements depend on several other factors,
most notably the interaction with the SGSN's flow control. They are
just examples to give an idea how CoDel might influence some
parameters.
The measurements have been done with a single E71, first with a
running ping only (Idle), then with an additional TCP download
of a 360k file (Busy). The CoDel interval was set to 1s.
- Idle :
ping ~400ms, avg queue delay 0ms, dropped 0
- Busy, No CoDel:
ping ~6s, avg queue delay 4-6s,
dropped 0, scheduled 948, duration 54s
- Busy, CoDel:
ping 500-1500ms, avg queue delay ~600ms,
dropped 77, scheduled 1040, duration 60s
More measurements with two MS downloading in parallel (two
independant measurements per case).
- Busy, No CoDel:
dropped 0, scheduled 1883, duration 121s
dropped 19, scheduled 2003, duration 133s
- Busy, CoDel:
dropped 22, scheduled 1926, duration 116s
dropped 22, scheduled 1955, duration 108s
Sponsored-by: On-Waves ehf
The idea behind this meta algorithm is to automatically select one of
the other algorithms based on the system state. Basically algorithm B
will be selected if the PDCH usage is low to improve throughput and
latency. Algorithm A will be selected to support more concurrent MS.
This commit adds a first simple state-less version of this algorithm
that always tries B first and only if that fails A is tried
afterwards.
The following VTY command is added to the 'pcu' node:
- alloc-algorithm dynamic
Ticket: #1934
Sponsored-by: On-Waves ehf
Pau Espin
Alexander Couzens
Philipp Maier
Vadim Yanitskiy
Oliver Smith
Harald Welte
Neels Hofmeyr