Commit graph

15 commits

Author SHA1 Message Date
Brad Beckmann
f5aa75fdc5 ruby: support to stallAndWait the mandatory queue
By stalling and waiting the mandatory queue instead of recycling it, one can
ensure that no incoming messages are starved when the mandatory queue puts
signficant of pressure on the L1 cache controller (i.e. the ruby memtester).

--HG--
rename : src/mem/slicc/ast/WakeUpDependentsStatementAST.py => src/mem/slicc/ast/WakeUpAllDependentsStatementAST.py
2011-02-06 22:14:19 -08:00
Nilay Vaish
c82a8979a3 Change interface between coherence protocols and CacheMemory
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.
2011-01-17 18:46:16 -06:00
Nilay Vaish
658849d101 ruby: Converted old ruby debug calls to M5 debug calls
This patch developed by Nilay Vaish converts all the old GEMS-style ruby
debug calls to the appropriate M5 debug calls.
2010-12-01 11:30:04 -08:00
Brad Beckmann
72044e3f5a ruby: Disable migratory sharing for token and hammer
This patch allows one to disable migratory sharing for those cache blocks that
are accessed by atomic requests.  While the implementations are different
between the token and hammer protocols, the motivation is the same.  For
Alpha, LLSC semantics expect that normal loads do not unlock cache blocks that
have been locked by LL accesses.  Therefore, locked blocks should not transfer
write permissions when responding to these load requests.  Instead, only they
only transfer read permissions so that the subsequent SC access can possibly
succeed.
2010-08-20 11:46:13 -07:00
Brad Beckmann
45f6f31d7a ruby: fixed token bugs associated with owner token counts
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.  :)
2010-08-20 11:46:13 -07:00
Brad Beckmann
29c45ccd23 ruby: Reduced ruby latencies
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.
2010-08-20 11:46:12 -07:00
Brad Beckmann
54d76f0ce5 ruby: Fixed L2 cache miss profiling
Fixed L2 cache miss profiling for the MOESI_CMP_token protocol
2010-08-20 11:46:12 -07:00
Brad Beckmann
a3b4b9b3e3 ruby: Added bcast msg profiling to hammer and token 2010-08-20 11:46:12 -07:00
Brad Beckmann
4b4e725921 ruby: Reincarnated the responding machine profiling
This patch adds back to ruby the capability to understand the response time
for messages that hit in different levels of the cache heirarchy.
Specifically add support for the MI_example, MOESI_hammer, and MOESI_CMP_token
protocols.
2010-08-20 11:46:12 -07:00
Brad Beckmann
b55e69ccac ruby: Removed the unnecessary MachineType message fields 2010-03-21 21:22:22 -07:00
Brad Beckmann
61f1d9a3d7 ruby: Reordered protocol buffers
Reordered vnet priorities to agree with PerfectSwitch for protocols MI_example,
MOESI_CMP_token, and MOESI_hammer
2010-03-21 21:22:21 -07:00
Brad Beckmann
1c4405ad5e ruby: Added atomic support to MOESI_CMP_token 2010-01-29 20:29:25 -08:00
Brad Beckmann
d77a9df3c1 ruby: MOESI_CMP_token updates to use the new config system 2010-01-29 20:29:25 -08:00
Brad Beckmann
5d8a669539 Resurrection of the CMP token protocol to GEM5 2009-11-18 16:34:33 -08:00
Nathan Binkert
2f30950143 ruby: Import ruby and slicc from GEMS
We eventually plan to replace the m5 cache hierarchy with the GEMS
hierarchy, but for now we will make both live alongside eachother.
2009-05-11 10:38:43 -07:00