When Packet resource request is received, PCU will generate the
packet access reject if no resources are present. The encoding is done
based on section 7.1.3.2.1 and 8.1.2.5 of 44.060 version 7.27.0 Release 7.
This patch also includes the test case to validate the generated
packet access reject message.
This patch is integration tested on Osmo-trx setup with Ettus B210 board
and LG F70 MS with some simulation code changes in Osmo-pcu.
Change-Id: I05ff25124b58905586caa0c0c37023d69724f121
Adds spb counters at BTS level(show bts statistics).
Adds RLC/MAC downlink control msg at ms level(show ms imsi <imsi_val>).
Adds the number of coding schemes counter for UL at TBF level.
Change-Id: Icbe4ba95e34bea89ee36f532d099db68204b7c38
When PDAN/EPDAN with channel description is received, PCU will generate the
packet access reject if no resources are present. The encoding is done
based on section 7.1.3.2.1 and 8.1.2.5 of 44.060 version 7.27.0 Release 7.
This patch also includes the test case to validate the generated
packet access reject message.
This patch is integration tested on Osmo-trx setup with Ettus B210 board
and LG F70 MS with some simulation code changes in Osmo-pcu.
Change-Id: I096a3bb44a65533b9e9b091925dd5f70a8696d6
ARFCN is already part of TRX struct so there's no need to supply it
explicitly in a separate parameter. I've tested and those are the same
anyway.
Change-Id: I8e975c52cbc819427880093b1e5371fe1f8ce460
rlc_sent_dummy count the amount of dummy package which are
sent in case no data packet is in the queue.
Change-Id: Ia60eab853d9145980f30d63e4ce4b520b8c51381
Reviewed-on: https://gerrit.osmocom.org/85
Tested-by: Jenkins Builder
Reviewed-by: Holger Freyther <holger@freyther.de>
The counter rlc_sent has nothing to do with the TBF.
The RLC packet got sent in the gprs_rlcmac_sched().
Change-Id: I5d2b910ea7cc250f17530406eda3be9b29b051fd
Reviewed-on: https://gerrit.osmocom.org/84
Tested-by: Jenkins Builder
Reviewed-by: Holger Freyther <holger@freyther.de>
Currently the selection of a pending control message is done round
robin. It can possibly happen, that a DL assigment is sent on a DL
TBF while an UL assignment is pending. The MS will replace the old
DL TBF in that case, so that it can no longer be used for the PACCH
so that the UL assignment is lost.
Give assigment requests for the same direction a lower priority.
Sponsored-by: On-Waves ehf
Currently there are some places where tbf->control_ts != ts is
evaluated to check, whether ts is a control slot.
Replace these expressions by tbf->is_control_ts(ts) which does
the same whitout exposing internal fields.
Sponsored-by: On-Waves ehf
Currently the checks in that function are based on the different
internal TS values of a TBF. It is assumed that they match the TS
that the current RTS refers to.
This commit adds a TS parameter to create_ul_ass, create_dl_ass,
and create_ul_ack to make this more explicit.
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
Currently the msg data is accessed and index 0 assuming the msg is
not empty. While this should be always the case, the msg can be
empty if there are software errors in the message creation functions.
This commit adds an assertion to catch this kind of bugs.
Sponsored-by: On-Waves ehf
Currently the control block scheduler does not seem to be fair in all
cases. At least it happend while testing the EGPRS code, that a
Uplink Ack/Nack message got never be sent, because a Downlink
assignment took over all the times.
This commit changes the round robin code to always increment the
priority offset by 1 instead of (i + 1). The former definitely
ensures that every message type gets the highest priority after some
steps. The latter might be more fair in some situations, but that and
its correctness are not proven.
Sponsored-by: On-Waves ehf
The leak rate sent to the SGSN does not reflect the current CS level,
lost frames, and control message overhead. So the SGSN cannot do
proper queue control under non-optimal conditions.
This commit computes the leak rate for the last flow control interval
by computing the maximum theoretical leak rate and basically
substracting control blocks, nacked blocks, and reduced block sizes
due to CS downgrade. By using this approach, the value will by more
stable on low load, where the value will tend to be near the value
derived from the configuration. On full load the transmitted value is
completely derived from the measurements.
Note that the MS default values are no adapted to the adapted BVC
leak rate, since a single MS which has a lower link quality would
otherwise be reducing the rate of another MS with good radio
conditions, which would not make much sense if they did not share any
PDCH.
Sponsored-by: On-Waves ehf
If an MS wants to open a new UL TBF, it can either use (P)RACH or
request one in a Ack/Nack message for a DL TBF (PACCH). When a TBF
becomes idle (LCC queue is empty but the TBF is kept open), there
aren't any Ack/Nack requests that can be used by the MS to ask for an
UL TBF, therefore it has to use the RACH. This leads to many RACH
requests even for a single HTTP transaction, so it takes some time to
retrieve even a simple web page.
This commit modifies the scheduler to regularly send Ack/Nack
requests on idle DL TBFs. It does so by extending the priority based
scheduling algorithm to have 5 priority levels (highest priority
first):
- Control block is pending
- High age (100%) threshold reached (-> request Ack/Nack)
- Data is waiting or there are pending Nacks
- Low age (200ms) threshold reached (-> request Ack/Nack)
- Pending Nacks that have been resent already
- None of the above (-> send DL dummy control block)
The 'age' refers to the time since since the last control block has
been sent on the TBF. This high age threshold is set to
dl-tbf-idle-time or to 50% of T3190 (whichever is smaller), aiming
for at least a poll (and TBF shutdown) after the TBF has expired and
to safely prevent expiry of T3190. So if dl-tbf-idle-time > 200ms,
there will be a poll every 200ms and a final poll after
dl-tbf-idle-time. On high load, the interval between polls can get
higher, but the 'high age' poll should be in place.
This commit implements the scheduling with respect to GSM 44.060,
9.3.1a ("Delayed release of downlink TBF").
Ticket: #556
Sponsored-by: On-Waves ehf
Currently the DL blocks are scheduled round robin to each TBF that is
either in state FLOW or FINISHED and not waiting for an IMM.ASS
confirmation. This way, if single blocks has been NACK'ed by the MS
and the PCU has already resent the missing packets, the PCU starts
retransmitting them until it has received an ACK/NACK even if other
TBF have RLC blocks that need to be transmitted.
This commit changes sched_select_downlink to select the next TBF with
the highest priority, where blocks that are going to be resent again
have a lower priority unless the window is stalling. If there is only
one TBF the old behaviour is kept, since there is no other TBF that
can have a higher priority.
If there is much packet loss on a single phone, this modification can
lead to a higher latency for that MS.
Sponsored-by: On-Waves ehf
There is no need for the union/struct anymore. Make the variable members
of the UL/DL class.
As a result gprs_rlc_dl_window gets a reset() method because
memset(&dir.dl, 0, sizeof(dir.dl)) doesn't work anymore in reuse_tbf().
Ticket: SYS#389
Sponsored by: On-Waves ehf
These functions are only used for DL TBFs so move them.
sched_select_downlink() in src/gprs_rlcmac_sched.cpp now needs to deal
with DL TBFs instead of the base class.
Ticket: SYS#389
Sponsored-by: On-Waves ehf
The PODS struct has a back pointer to access the actual object.
llist_pods_for_each_entry traverses the list of struct llist_pods and
makes the entry available (through the back pointer).
Ticket: SYS#389
Sponsored-by: On-Waves ehf
It is possible that certain UL ACK messages are not sent when there
are many many uplink and downlink assignments. Try to be more fair
and schedule them round-robin. This way no starvation should occur.
All logging code that used tbf->tfi is now using tbf_name to
print the the TBF. External code is now using tfi() which is
inlined and should result in the same code being generated as
before (+debug code that can be stripped).
TLLIs got printed as TBF. Fix that but also rename things to
TFI. The TFI is not required to be unique per BTS but it is
the indicator we use right now.
The list belongs to the BTS. This makes cleaning this up more easy
and establishes a hierachy of resources that start from the BTS. The
debug_diagram code is now broken.
The PollController is a friend of the SBAController and is allowed
to access the internal list. The list is hidden from everyone else.
This is done because the calculation of timeout should belong into
the PollController and not into the SBAController.
Rely on packet_paging_request returning NULL in case the queue
is empty. We should move the write_packet_paging_request into
a separate file/object as well.
When a PDCH is disabled all resources should be freed. This is
currently not possible as the PDCH does not know where it belongs
to. On top of that the list (and other resources) should be
properly initialized on construction so that disable() is idempotent
and does not check if it was disabled. During the re-factoring I
noticed that during a sysmobts re-start some resources are not
freed. I left a warning in the code to resolve this issue later.
aravind sirsikar
Neels Hofmeyr
Daniel Willmann