This commit fixes a bug caused by global variables in the gNB_MAC_INST
structure used to transfer MAC scheduler's results to the PHY layer.
When using several threads in the PHY layer, it may happen that the
MAC scheduler is called a second time by the second PHY thread for the
next slot before the content of the global variables in the gNB_MAC_INST
structure used to store the result of the MAC scheduler for the current
slot have been consumed by the first thread, leading to unpredictable
results (all of them certainly wrong).
The solution is to introduce a small memory management module for the
interface between the PHY threads and the MAC scheduler. The MAC
scheduler now fills the data structures passed to it, and not a
global variable anymore. The PHY layer manages the structures and
ensures that no data is overwritten before being fully consumed by
the various threads of the PHY layer.
Some care has to be taken because several PHY threads will access the
same structures at the same time for a given slot (in read mode, so
it's okay). A mechanism of reference counting has thus been introduced.
Only one CC is supported. This restriction should not be too hard
to remove if/when needed. (The code before this commit does not seem
to work for more than one CC anyway.)
The simulators have been changed: due to linker errors that would arise
otherwise, a lot of functions are defined in them to avoid such errors.
Some functions are also defined in header files; in this commit, we
define most functoins in nr_dummy_functions.c, which is compiled in, not
by including the C file, but by adding it to the target in
CMakeLists.txt
- nr_dlsim+nr_ulsim need NR_IF_Module_init(), so it cannot be in
nr_dummy_functions, but the others need it
- Link correcr NR_IF_Module_init() into these simulators, and reduce
overall link list
- Correctly link remaining simulators
This commit provides CSI reporting support
which is required for MIMO. It also updates
the configuration files, provides sample BLER
simualtion files for packet dropping in the
MIMO 2x2 case. It also includes the hooks
and functions (e.g., updating UCI2_3_4 PDU field)
for MIMO 2x2 support. This commit will not include
any channel abstraction code or modelling.
Cedric Roux