The way allocation is done (granularity of 64KiB) makes a crash more
difficult to achieve, but if a trace is exactly 64KiB, we miss 4 bytes
in the realloc and then anything may happen.
Useful to debug realtime issues, for example when calling a periodical
routine, if it's not programmed carefully enough, it may be that the first
call takes way longer than the next ones (for example it uses some memory
that is not mapped in the process, leading to many page faults the first
time it's executed).
Having a periodic log for the timing of this routine with min/avg/max/count
will reveal that a call is way longer than average and will help in
finding where exactly in the code the time is spent, thanks to the ease
of use of the T tracer; you put T(T_XX, T_INT(1)) just before the code
you want to measure, you put T(T_XX, T_INT(0)) just after and time_meas
will show the delta time between those events. Then you cut the routine
in smaller pieces, measure with T(1)/T(0), and you finally reach the small
guilty part that takes too long.
In time_meas.c, when getting 0 for the event, we log delta time with
previous 1 for the event. "start_valid" was not cleared, so receiving
a second 0 without 1 in between may lead to wrong logging.
Should not happen in practice, but still, little bug.
(Note: we don't protect against streams of 1, but this case should also
not happen.)
There is already common/utils/config.h. This file(name) is hardcoded as
it is included into asn1c, and cannot be renamed. To avoid a name clash
and confusing, we rename T's config.h/c to configuration.h/c.
This commit introduces an alternative RLC implementation
based on 36.322 version 8. AM and UM done, TM not done.
See openair2/LAYER2/rlc_v2/TODO for missing parts.
Whenever the value T_BUFFER_MAX changes, the tracers had to
be recompiled. The only reason why it was needed is because we
used some fixed size buffers to read events. This commit removes
this restriction.
Also, with the basic simulator, this value T_BUFFER_MAX now comes
with an #ifdef which would have required some special hackish-level
tricks in the tracers, which is not good.
Let's just allocate memory when needed.