This patch simplifies the packet by removing the broadcast flag and
instead more firmly relying on (and enforcing) the semantics of
transactions in the classic memory system, i.e. request packets are
routed from a master to a slave based on the address, and when they
are created they have neither a valid source, nor destination. On
their way to the slave, the request packet is updated with a source
field for all modules that multiplex packets from multiple master
(e.g. a bus). When a request packet is turned into a response packet
(at the final slave), it moves the potentially populated source field
to the destination field, and the response packet is routed through
any multiplexing components back to the master based on the
destination field.
Modules that connect multiplexing components, such as caches and
bridges store any existing source and destination field in the sender
state as a stack (just as before).
The packet constructor is simplified in that there is no longer a need
to pass the Packet::Broadcast as the destination (this was always the
case for the classic memory system). In the case of Ruby, rather than
using the parameter to the constructor we now rely on setDest, as
there is already another three-argument constructor in the packet
class.
In many places where the packet information was printed as part of
DPRINTFs, request packets would be printed with a numeric "dest" that
would always be -1 (Broadcast) and that field is now removed from the
printing.
This change adds a master id to each request object which can be
used identify every device in the system that is capable of issuing a request.
This is part of the way to removing the numCpus+1 stats in the cache and
replacing them with the master ids. This is one of a series of changes
that make way for the stats output to be changed to python.
One big difference is that PrioHeap puts the smallest element at the
top of the heap, whereas stl puts the largest element on top, so I
changed all comparisons so they did the right thing.
Some usage of PrioHeap was simply changed to a std::vector, using sort
at the right time, other usage had me just use the various heap functions
in the stl.
In addition to obvious changes, this required a slight change to the slicc
grammar to allow types with :: in them. Otherwise slicc barfs on std::string
which we need for the headers that slicc generates.
Modified ruby's tracing support to no longer rely on the RubySystem map
to convert a sequencer string name to a sequencer pointer. As a
temporary solution, the code uses the sim_object find function.
Eventually, we should develop a better fix.
This was done with an automated process, so there could be things that were
done in this tree in the past that didn't make it. One known regression
is that atomic memory operations do not seem to work properly anymore.
This basically means changing all #include statements and changing
autogenerated code so that it generates the correct paths. Because
slicc generates #includes, I had to hard code the include paths to
mem/protocol.
1) Removing files from the ruby build left some unresovled
symbols. Those have been fixed.
2) Most of the dependencies on Simics data types and the simics
interface files have been removed.
3) Almost all mention of opal is gone.
4) Huge chunks of LogTM are now gone.
5) Handling 1-4 left ~hundreds of unresolved references, which were
fixed, yielding a snowball effect (and the massive size of this
delta).