Try to merge feature-68-enb-agent into develop
develop should be fast-forwarded later to this branch to complete the merge
This code does not compile yet. Among other things:
- the scheduler structure needs to be reworked for FlexRAN
- the config is structured differently. The files enb_config.{c,h} from develop
have been copied in here, the files with merge annotations are in
enb_config.{c,h}.before_merge
- the restart needs to be restructured, since the PHY vars data structure lives
in RC now
How to use:
1 - compilation of softmodem:
./build_oai --eNB -t ETHERNET
2 - compilation of mobipass driver:
cd cmake_targets/lte_build_oai/build
make oai_mobipass
ln -sf liboai_mobipass.so liboai_transpro.so
3 - configuration:
edit the configuration file, set "node_timing" to
"synch_to_mobipass_standalone"
that is, have the line:
node_timing = "synch_to_mobipass_standalone";
4 - run:
run as usual: sudo ./lte-softmodem -C <configuration file>
- rename UE_NO_LOG to DISABLE_LOG_X
because the name is misleading. The full software
is impacted, not only the UE part
- same for compilation option ---ue-no-log
that becomes --disable-log
- keep LOG_X for the standard case, that is the
case without DISABLE_LOG_X where printf has been
put. Two reasons:
* printf is not realtime friendly
* keep behavior similar for other users who may
be troubled by different logs that don't add
any benefit to previous logs
- import RRC ASN.1 defintions from the specifications
(file openair2/RRC/LITE/MESSAGES/asn1c/ASN1_files/RRC-e10.asn)
contrary to rel8/10, all modules have been imported, maybe it's too much
to refine in case of problems
- deal with rel14 in fix_asn1
- all code that was for Rel10 is now for Rel10/Rel14
- some incompatible changes (mostly in naming) were resolved in favor
of rel14, see in openair2/RRC/LITE/defs.h
- unsure about the rlc layer, some arrays have changed (values appended),
I only changed the definition and in tests in the code, I changed
the index limit, maybe it's not enough
Rel14 is the default compilation mode.
see https://gitlab.eurecom.fr/oai/openairinterface5g/issues/227
When the UE connects to the eNodeB and receives its IP address from the
network, it calls system() to set it in the linux kernel world. This call
is not done in a realtime thread, but in the NAS, which uses its own thread,
independent of the realtime processing.
In some situations this totally disrupts realtime processing.
It is difficult to know precisely why that happens, but it seems that calling
fork(), as system() does, in a multi-threaded program is not a good idea. (So
say several people on the internet.) It is not clear why the softmodem is
impacted, but it seems that fork() is really what triggers the disruption.
Several tests lead to that conclusion.
To fix the problem, we create a child background process very early in main()
(before anything else basically). Then instead of calling system(), the main
process sends the string to the background process. The background process
gets the string, passes it to system() and reports the success/failure back
to the main process.
This solution involves a lot of system calls, but calling system() in the
first place is not cheap either. As long as no realtime thread uses this
mechanism, things should be fine. Time will tell.
On some hosts, compilations with the T tracer was failing.
The error was:
common/utils/T/T.h:15:19: fatal error: T_IDs.h: No such file or directory
The problem was that in CMakeLists.txt some targets depend on the
pre-generation of T_IDs.h but this dependancy relation was not set,
so those targets could be generated before the T (it was the case
with HASHTABLE).
This commit fixes that. Basically, we take all the targets found in
"add_executable" and "add_library" and make them depend on the
T if the T is enabled. Almost all existing targets were added,
even those that may not need it.
The problem of this approach is that someone adding a new target
using the T will not necessarily add a dependancy there.
Another solution would be to generate T_IDs.h at "cmake" stage,
not "make" stage and use an "if (NOT EXISTS T_IDs.h)" to generate
the file. We lose the dependancy relation though.
Things may be changed if maintenance cost is too high.
Robert Schmidt