These fixes do not affect the semantics of the code. They either help
gcc by providing default values that won't be used ("may be
uninitialised"), remove unused variables, or change signed to
unsigned variables to avoid comparison warnings.
Addresses:
bts.cpp:494:32: warning: 'tbf' may be used uninitialized in this
function
emu/test_replay_gprs_attach.cpp:81:27: warning: comparison between
signed and unsigned integer expressions
emu/test_pdp_activation.cpp:95:23: warning: unused variable ‘budh’
emu/test_pdp_activation.cpp:97:6: warning: variable ‘rc’ set but
not used
emu/pcu_emu.cpp:109:26: warning: unused variable ‘bts’
alloc/AllocTest.cpp:74:27: warning: unused variable ‘tbf’
osmocom/core/utils.h:13:50: warning: comparison between signed and
unsigned integer expressions
types/TypesTest.cpp:319:7: warning: unused variable ‘count’
types/TypesTest.cpp:320:11: warning: unused variable ‘rbb’
alloc/AllocTest.cpp:74:27: warning: unused variable ‘tbf’
alloc/AllocTest.cpp:132:11: warning: unused variable ‘ts_no’
Currently two DL TBF objects with the same TLLI exist after reuse_tbf
which make the result of tbf_by_tlli undefined. This leads to several
DL TBFs belonging to the same TLLI.
This commit extends tbf_by_tlli to check the m_tlli_valid flag for
DL, too. That flag is set to 0 in reuse_tbf to mark the 'old' DL TBF
as invalid after its LLC data has been copied to the new one.
Sponsored-by: On-Waves ehf
There are a couple of possibilities where one TBF is used to assign a
new one:
1. Assign a DL TBF from a UL TBF
2. Assign a UL TBF from a DL TBF
3. Assign a DL TBF from a DL TBF which is in wait-release state (T3193 is
running)
In these cases the assignment is sent on the existing TBF and triggers
the assignement of the new TBF (with different TFI/direction).
The current code detects these situations by looking at dl/ul_ass_state
and then chosing the TBF with the opposite direction (DL/UL) that has
the same TLLI. This does not work in the case 3 above where a new DL TBF
is triggered for a DL TBF. The current code reuses the old TBF (and
TFI), but this violates the spec.
This patch introduces a m_new_tbf member which is set to the new TBF to
be assigned. When receiving a control ack the code looks up the
n_new_tbf member of the tbf that requested the control ack and completes
the ul/dl assignment. If the old TBF was in the wait release state
(T3193 is running) it is released.
From 3GPP TS 04.60 9.3.2.6:
"""
If the network has received the PACKET DOWNLINK ACK/NACK message with
the Final Ack Indicator bit set to '1' and has new data to transmit for
the mobile station, the network may establish a new downlink TBF for the
mobile station by sending the PACKET DOWNLINK ASSIGNMENT or PACKET
TIMESLOT RECONFIGURE message with the Control Ack bit set to '1' on
PACCH. In case the network establishes a new downlink TBF for the mobile
station, the network shall stop timer T3193.
"""
reuse_tbf() is modified to allocate a new TBF with a new TFI and trigger
a dl assignment for that TBF on the old TBF. All pending data is moved
to the new TBF.
Ticket: SYS#382
Sponsored-by: On-Waves ehf
All the function did was add debug output and call the set_state method.
Move the debugging into the method and remove the function.
Ticket: SYS#389
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
This method is only userul for DL TBFs so move it. As a result
gprs_rlcmac_pdch::rcv_control_ack needs to work with dl_tbfs.
Ticket: SYS#389
Sponsored-by: On-Waves ehf
llist_add is called on the TBF lists in tbf_alloc_ul/dl_tbf or in
rotate_in_list. All three places check the direction/add the new TBF to
the correct list so an ASSERT on entry is not needed.
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
UL and DL tbfs are used in very separate parts and are not the same
thing so split the alloc function and use the UL/DL version throughout
the code.
Ticket: SYS#389
Sponsored-by: On-Waves ehf
Many functions only ever deal with or return a UL or a DL TBF.
Explicitly change the type to reflect which TBF is used where.
Ticket: SYS#389
Sponsored-by: On-Waves ehf
rcv_control_dl_ack_nack is only meaningful for dl tbf while
rcv_control_ack can be sent in response to a dl or ul tbf. So
rcv_control_ack still needs to check for ul and dl tbfs.
Ticket: SYS#389
Sponsored-by: On-Waves ehf
The current code keeps a reference to all tbfs in the bts and another
reference in the pdch. This allows for the possibility of both lists to
go out of sync.
This patch removes the pdch-specific list of ul and dl tbfs and uses the
lists in the bts to lookup tbfs everywhere.
Performance for going through the global list is not an issue yet. We
can optimize this later and in a better way.
Sponsored-by: On-Waves ehf
The current code does not properly distinguish between DL assignments to
reuse a tbf (after it was put in state WAIT_RELEASE) and DL assignments
for an active tbf to change the allocation of the PDCH timeslots.
This patch introduces a new variable was_releasing which remembers if
trigger_dl_ass() was called with a tbf in state WAIT_RELEASE. In that
case we have to set the CONTROL_ACK field in the download assignment.
This should allow us to send DL assignments to change PDCH TS allocation
of a tbf before we enter FLOW state.
This approach is somehow flawed. We need/want to debug problems on
systems with real traffic and re-compiling it with debug_diagram
is not an option. All internal logging needs to be expressive enough
so we can understand what is going on (e.g. create a script to
post-process the output).
This does not mean that they have been successfully transferred
to the SGSN/MS but at least that they have reached a certain point
in the message flow.
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).
Now all updates to the tlli/tlli_valid are in one place. If we
implement the policy to update the matching/linked TBF we can
now to do it in a single place. Add a todo item for that as I
am waiting for feedback from the mailinglist.
This is like gsm_lchan_name and should be used in log statements.
This way we can easily change the information that is printed and
we know how to search things. The other part is that direct use
of tfi/tlli is removed which will allow us to make them private
and at the same time start to resolve the "tlli" updated in many
places.
Not old log statements are changed yet. This will done whenever
a bad log statement is seen on the console...
The TLLI can change when a new P-TMSI is assigned to the phone,
e.g. during a (periodic) routing area update. When the TLLI
changes we need to update all TBFs and maybe even register the
timing advance for the new TLLI..
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.
Jacob Erlbeck
Daniel Willmann