A few prior changesets have changed the gem5 output in a way that wont cause
errors but may be confusing for someone trying to debug the regressions. Ones that I caught
were:
- no more "warn: <hash address"
- typo in the ALPHA Prefetch unimplemented warning
Additionaly, the last updated stats changes rearrange the ordering of the stats output even though
they are still correct stats (gem5 is smart enough to detect this). All the regressions pass
w/the same stats even though it looks like they are being changed.
Re-enabling implicit parenting (see previous patch) causes current
Ruby config scripts to create some strange hierarchies and generate
several warnings. This patch makes three general changes to address
these issues.
1. The order of object creation in the ruby config files makes the L1
caches children of the sequencer rather than the controller; these
config ciles are rewritten to assign the L1 caches to the
controller first.
2. The assignment of the sequencer list to system.ruby.cpu_ruby_ports
causes the sequencers to be children of system.ruby, generating
warnings because they are already parented to their respective
controllers. Changing this attribute to _cpu_ruby_ports fixes this
because the leading underscore means this is now treated as a plain
Python attribute rather than a child assignment. As a result, the
configuration hierarchy changes such that, e.g.,
system.ruby.cpu_ruby_ports0 becomes system.l1_cntrl0.sequencer.
3. In the topology classes, the routers become children of some random
internal link node rather than direct children of the topology.
The topology classes are rewritten to assign the routers to the
topology object first.
This change fixes the problem for all the cases we actively use. If you want to try
more creative I/O device attachments (E.g. sharing an L2), this won't work. You
would need another level of caching between the I/O device and the cache
(which you actually need anyway with our current code to make sure writes
propagate). This is required so that you can mark the cache in between as
top level and it won't try to send ownership of a block to the I/O device.
Asserts have been added that should catch any issues.
makeArmSystem creates both bare-metal and Linux systems more cleanly.
machine_type was never optional though listed as an optional argument; a system
such as "RealView_PBX" must now be explicitly specified. Now that it is a
required argument, the placement of the arguments has changed slightly
requiring some changes to calls that create ARM systems.
previous changesets took a closer look at memory mgmt in the inorder model and sought to avoid
dynamic memory mgmt (for access to pipeline resources) as much as possible. For the regressions
that were run, the sims are about 2x speedup from changeset 7726 which is the last change
since the recent commits in Feb. (note: these regressions now are 4-issue CPUs instead of just 1-issue)
there are still only a few inorder benchmark but for the lengthier benchmarks (twolf and vortext)
the latest changes to how instruction scheduling (how instructions figure out what they want to
do on each pipeline stage in the inorder model) were able to improve performance by a nice
amount... The latest results for the inorder model process about 100k insts/second
(note: 58% is over the last time run on 64-bit pool machines at UM)
