This should allow m5 to be more easily embedded into other simulators.
The m5 binary adds a simple main function which then calls into the m5
libarary to start the simulation. In order to make this work
correctly, it was necessary embed python code directly into the
library instead of the zipfile hack. This is because you can't just
append the zipfile to the end of a library the way you can a binary.
As a result, Python files that are part of the m5 simulator are now
compile, marshalled, compressed, and then inserted into the library's
data section with a certain symbol name. Additionally, a new Importer
was needed to allow python to get at the embedded python code.
Small additional changes include:
- Get rid of the PYTHONHOME stuff since I don't think anyone ever used
it, and it just confuses things. Easy enough to add back if I'm wrong.
- Create a few new functions that are key to initializing and running
the simulator: initSignals, initM5Python, m5Main.
The original code for creating libm5 was inspired by a patch Michael
Adler, though the code here was done by me.
I decided that separating some of the scons code into generate.py was
just a bad idea because it caused the dependency system to get all
messed up. If separation is the right way to go in the future, we
should probably use the sconscript mechanism, not the mechanism that I
just removed.
- Add the option of redirecting stderr to a file. With the old
behaviour, stderr would follow stdout if stdout was to a file, but
stderr went to the host stderr if stdout went to the host stdout. The
new default maintains stdout and stderr going to the host. Now the
two can specify different files, but they will share a file descriptor
if the name of the files is the same.
- Add --output and --errout options to se.py to go with --input.
- insert warnings for deprecated m5ops
- reserve opcodes for Ali's stuff
- remove code for stuff that has been deprecated forever
- simplify m5op_alpha
The status quo is preferred since it is less likely that people will
rely on LIFO than FIFO, and when we move to a parallelized M5, no
ordering between events of the same time/priority will be guaranteed.
linked list sorted by time and priority. For things of the same time
and priority, a second, circularly linked list maintains the data
structure. Events of the same time and priority are now inserted in
FIFO order instead of LIFO order. This dramatically improves the
performance of systems that schedule multiple events at the same time.
The FIFO order version is not preferred to LIFO (because it may cause
people to rely on it), but I'm going to commit it anyway and
immediately commit the preferred LIFO version on top.
This appears to work, but I don't want to commit it until it gets tested a lot more.
I haven't deleted the functionality in this patch that will come later, but one question
is how to enforce encourage objects that call getVirtPort() to not cache the virtual port
since if the CPU changes out from under them it will be worse than useless. Perhaps a null
function like delVirtPort() is still useful in that case.
The notIdleFraction statistic isn't updated when the statistics reset, probably because the cpu Status information
was pulled into the atomic and timing cpus. This changeset pulls Status back into the BaseSimpleCPU object. Anyone
care to comment on the odd naming of the Status instance? It shouldn't just be status because that is confusing
with Port::Status, but _status seems a bit strage too.