The existing code prevents double initialization if e.g., both gNB&UE
call these functions (like in a simulator). However, in the case of a
double-initialization such as stopping and re-starting the L1, the
memory will be freed, but not freed again. Basically, this works:
generate()
generate() # not initialized again
but this leads to problems:
generate()
free()
generate() # not initialized again, but should be!
Reimplement the check based on the data to be initialized, such that an
intermediate free() will be handled properly.
These are the "main" worker threads (apart the ru_thread). If the
thread-pool stops, they might get stuck. E.g., in PUSCH channel
estimation, it uses a local response queue, and if the thread pool is
terminated, it seems that the L1_rx_thread can get stuck in there.
To limit these problems, attempt to stop these threads first; stop the
queue from which they read and make them terminate; then, stop the
thread pool.
Also, fix the termination of respPuschSymb queue.
A later commit implements the "restart" of the L1. The L1 reads
configuration options. First, allow to re-read configurations by
increasing the amount of memory the config module might allocate. Then,
avoid an out-of-bound write by checking that we still have memory
available (and assert if not possible).
New LDPC coding library interface for decoding and encoding complete slots in one call to the library
Previous attempts to integrate LDPC decoding relying on offloading show
the limitation of the original code segment coding interface for the
library implementing LDPC coding. In order to perform the offload and
therefore the decoding in an optimal fashion, it is relevant to provide
the implementation with the broader amount of data possible per call,
which is a slot. A previous MR related to T2 offload managed to offer
an interface for decoding transport blocks by modifying only
nr_ulsch_decoding.c. But this may not be sufficient for performing an
efficient decoding in any situation. Slots could be shared between
multiple transport blocks in case multiple UEs are connected to the RAN,
which makes the transport block size shrink and therefore degrades the
efficiency of the offloading.
This MR offers a broader interface with a gNB decoding entry point in
phy_procedures_nr_gNB.c. The file nr_ulsch_decoding.c now lets the
decoding library implement deinterleaving, rate-unmatching and decoding
for the slot. In gNB encoding and UE decoding and encoding as well,
tasks are partitioned in a similar fashion.
As it allows to feed the implementation with the broadest amount of data
possible, it allows to fit any coding solution in a library. This will
avoid further modification to OAI source code and addition of options to
select an implementation when integrating new decoding solutions. An
implementation of this interface will therefore be offered for every
existing decoding solution in OAI and solutions added in the future will
be provided as independent module code without any modification to the
core of OAI code. The way to choose the decoding solution and to
configure it was also unified using configmodule. The library can be
chosen through the option --loader.ldpc.shlibversion. The slot coding
solutions shipped with this MR can be configured through configmodule
(e.g., T2 address and isolated cores).
This MR includes three coding implementations:
- A wrapper around segment decoding libraries for test purpose: libldpc.so
- A one shot slot coding and encoding with the T2 board: libldpc_t2.so
- A decoder on FPGA using the XDMA driver: libldpc_xdma.so
Improvements brought by this MR:
- Easy integration of a wider variety of LDPC coding solution at gNB and UE
- Easy selection of the LDPC coding solution (option --ldpc-offload-enable is kept for now but it can be ultimately removed)
- T2:
* More efficient when many UEs are connected
* Decoding and encoding in nr-uesoftmodem
NGAP-Initial Context Setup Failure
NGAP Failure message - Initial Context Setup Failure. When an Initial
Context Setup Request is received with the UE context as null, it
triggers Initial Context Setup failure
SIB19 utilization on UE
Following SIB19 initialization and scheduling on gNB (!2899 - merged)
and Receive SIB19 on nrUE (!2920 - merged), this merge request aims to
introduce the actual use of the SIB19 provided parameters by gNB in UE.
Changes needed for utilization include: initialization of position
coordinates parameters for UE (which are needed to calculate propagation
delay between UE and SAT), propagation delay calculations and timing
advance adjusts. Moreover, this change removes the now unused arguments
for ntn_koffset, ntn_ta_common and ntn_ta_commondrift
GTP: use direct call instead of ITTI
Using ITTI calls for user plane implies (1) a memory allocation, (2)
mutexes, and (3) queueing messages for each user plane packet, which is
heavy. Use a direct API call instead to reduce overhead.
It seems that the cyclic prefix is in most cases a multiple of 512 samples.
This means that in most cases the idft output pointer is already aligned and
there is no need to perform an extra memcpy. This saves the memcpy time in
most cyclic prefix insertion cases.
More complex implementations will be achieved using the new reworked interface
- t_nrLDPC_dec_params: remove F, Qm, rv and perCB
- encoder_implemparams_t: remove Qm, Tbslbrm, G, rv and perCB
- Remove all variables (like OPENAIR1), they serve no purpose and make
unnecessarily long lines
- Remove linking to T, it does not seem to be necessary
- Avoid intermediate variables to keep sources, and declare libraries
directly, making for shorter code
NGAP Failure message - Initial Context Setup Failure.
When an Initial Context Setup Request is received with the UE context as null, it triggers Initial Context Setup failure.
Fix several issues in ulsch_mmse_2layers
Fix incorrect array type of determ_fin which was set to int32_t while the
array holds the results of simde_mm_abs_epi32 which produces unsigned
values.
Remove assert on right-shifting negative integers as it is impossible for
determ_fin to hold negative values.
Change type of sum_det to uint32_t to prevent possible overflow. Fix
the type cast (int -> uint32_t) to prevent casting before shift in
nr_ulsch_comp_muli_sum which might have resulted in right shifting
negative integers.
Closes: #753
UE data race fix
When a new sync request is sent to PHY, we clear harq buffer and start
synchronization process. This could lead to unexpected behavior or segv
because DL actors might be using the buffer we just cleared. To avoid
this, the DL actors are shutdown and re initiated before clearing harq
info.