This patch rpovides functional access support in Ruby. Currently only
the M5Port of RubyPort supports functional accesses. The support for
functional through the PioPort will be added as a separate patch.
The access permissions for the directory entries are not being set correctly.
This is because pointers are not used for handling directory entries.
function. get and set functions for access permissions have been added to the
Controller state machine. The changePermission() function provided by the
AbstractEntry and AbstractCacheEntry classes has been exposed to SLICC
code once again. The set_permission() functionality has been removed.
NOTE: Each protocol will have to define these get and set functions in order
to compile successfully.
Identifying response vnets versus other vnets will allow garnet to
determine which vnets will carry data packets, and which will carry
ctrl packets, and use appropriate buffer sizes (since data packets are larger
than ctrl packets). This in turn allows the orion power model to accurately
estimate buffer power.
In SLICC, in order to define a type a data type for which it should not
generate any code, the keyword external_type is used. For those data types for
which code should be generated, the keyword structure is used. This patch
eliminates the use of keyword external_type for defining structures. structure
key word can now have an optional attribute external, which would be used for
figuring out whether or not to generate the code for this structure. Also, now
structures can have functions as well data members in them.
This patch integrates permissions with cache and memory states, and then
automates the setting of permissions within the generated code. No longer
does one need to manually set the permissions within the setState funciton.
This patch will faciliate easier functional access support by always correctly
setting permissions for both cache and memory states.
--HG--
rename : src/mem/slicc/ast/EnumDeclAST.py => src/mem/slicc/ast/StateDeclAST.py
rename : src/mem/slicc/ast/TypeFieldEnumAST.py => src/mem/slicc/ast/TypeFieldStateAST.py
The purpose of this patch is to change the way CacheMemory interfaces with
coherence protocols. Currently, whenever a cache controller (defined in the
protocol under consideration) needs to carry out any operation on a cache
block, it looks up the tag hash map and figures out whether or not the block
exists in the cache. In case it does exist, the operation is carried out
(which requires another lookup). As observed through profiling of different
protocols, multiple such lookups take place for a given cache block. It was
noted that the tag lookup takes anything from 10% to 20% of the simulation
time. In order to reduce this time, this patch is being posted.
I have to acknowledge that the many of the thoughts that went in to this
patch belong to Brad.
Changes to CacheMemory, TBETable and AbstractCacheEntry classes:
1. The lookup function belonging to CacheMemory class now returns a pointer
to a cache block entry, instead of a reference. The pointer is NULL in case
the block being looked up is not present in the cache. Similar change has
been carried out in the lookup function of the TBETable class.
2. Function for setting and getting access permission of a cache block have
been moved from CacheMemory class to AbstractCacheEntry class.
3. The allocate function in CacheMemory class now returns pointer to the
allocated cache entry.
Changes to SLICC:
1. Each action now has implicit variables - cache_entry and tbe. cache_entry,
if != NULL, must point to the cache entry for the address on which the action
is being carried out. Similarly, tbe should also point to the transaction
buffer entry of the address on which the action is being carried out.
2. If a cache entry or a transaction buffer entry is passed on as an
argument to a function, it is presumed that a pointer is being passed on.
3. The cache entry and the tbe pointers received __implicitly__ by the
actions, are passed __explicitly__ to the trigger function.
4. While performing an action, set/unset_cache_entry, set/unset_tbe are to
be used for setting / unsetting cache entry and tbe pointers respectively.
5. is_valid() and is_invalid() has been made available for testing whether
a given pointer 'is not NULL' and 'is NULL' respectively.
6. Local variables are now available, but they are assumed to be pointers
always.
7. It is now possible for an object of the derieved class to make calls to
a function defined in the interface.
8. An OOD token has been introduced in SLICC. It is same as the NULL token
used in C/C++. If you are wondering, OOD stands for Out Of Domain.
9. static_cast can now taken an optional parameter that asks for casting the
given variable to a pointer of the given type.
10. Functions can be annotated with 'return_by_pointer=yes' to return a
pointer.
11. StateMachine has two new variables, EntryType and TBEType. EntryType is
set to the type which inherits from 'AbstractCacheEntry'. There can only be
one such type in the machine. TBEType is set to the type for which 'TBE' is
used as the name.
All the protocols have been modified to conform with the new interface.
This patch fixes several bugs related to previous inconsistent assumptions on
how many tokens the Owner had. Mike Marty should have fixes these bugs years
ago. :)
The previous slower ruby latencies created a mismatch between the faster M5
cpu models and the much slower ruby memory system. Specifically smp
interrupts were much slower and infrequent, as well as cpus moving in and out
of spin locks. The result was many cpus were idle for large periods of time.
These changes fix the latency mismatch.
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.
