Commit graph

1436 commits

Author SHA1 Message Date
Andreas Hansson
49d88f08b0 mem: Change AbstractMemory defaults to match the common case
This patch changes the default parameter value of conf_table_reported
to match the common case. It also simplifies the regression and config
scripts to reflect this change.
2013-08-19 03:52:33 -04:00
Andreas Hansson
6279eaf1f7 mem: Use STL deque in favour of list for DRAM queues
This patch changes the data structure used for the DRAM read, write
and response queues from an STL list to deque. This optimisation is
based on the observation that the size is small (and fixed), and that
the structures are frequently iterated over in a linear fashion.
2013-08-19 03:52:32 -04:00
Andreas Hansson
ac42db8134 mem: Perform write merging in the DRAM write queue
This patch implements basic write merging in the DRAM to avoid
redundant bursts. When a new access is added to the queue it is
compared against the existing entries, and if it is either
intersecting or immediately succeeding/preceeding an existing item it
is merged.

There is currently no attempt made at avoiding iterating over the
existing items in determining whether merging is possible or not.
2013-08-19 03:52:31 -04:00
Amin Farmahini
243f135e5f mem: Replacing bytesPerCacheLine with DRAM burstLength in SimpleDRAM
This patch gets rid of bytesPerCacheLine parameter and makes the DRAM
configuration separate from cache line size. Instead of
bytesPerCacheLine, we define a parameter for the DRAM called
burst_length. The burst_length parameter shows the length of a DRAM
device burst in bits. Also, lines_per_rowbuffer is replaced with
device_rowbuffer_size to improve code portablity.

This patch adds a burst length in beats for each memory type, an
interface width for each memory type, and the memory controller model
is extended to reason about "system" packets vs "dram" packets and
assemble the responses properly. It means that system packets larger
than a full burst are split into multiple dram packets.
2013-08-19 03:52:30 -04:00
Andreas Hansson
d5593f3c75 mem: Warn instead of panic for tXAW violation
Until the performance bug is fixed, avoid killing simulations.
2013-08-19 03:52:26 -04:00
Andreas Hansson
7bc3eaec7a mem: Allow disabling of tXAW through a 0 activation limit
This patch fixes an issue where an activation limit of 0 was not
allowed. With this patch, setting the limit to 0 simply disables the
tXAW constraint.
2013-08-19 03:52:26 -04:00
Andreas Hansson
2a675aecb9 mem: Add an internal packet queue in SimpleMemory
This patch adds a packet queue in SimpleMemory to avoid using the
packet queue in the port (and thus have no involvement in the flow
control). The port queue was bound to 100 packets, and as the
SimpleMemory is modelling both a controller and an actual RAM, it
potentially has a large number of packets in flight. There is
currently no limit on the number of packets in the memory controller,
but this could easily be added in a follow-on patch.

As a result of the added internal storage, the functional access and
draining is updated. Some minor cleaning up and renaming has also been
done.

The memtest regression changes as a result of this patch and the stats
will be updated.
2013-08-19 03:52:25 -04:00
Nilay Vaish
95381f8a99 ruby: slicc: remove double trigger, continueProcessing
These constructs are not in use and are not being maintained by any one.
In addition, it is not known if doubleTrigger works correctly with Ruby now.
2013-08-07 14:51:18 -05:00
Nilay Vaish
f1b17bf157 ruby: slicc: move some code to AbstractController
Some of the code in StateMachine.py file is added to all the controllers and
is independent of the controller definition. This code is being moved to the
AbstractController class which is the parent class of all controllers.
2013-08-07 14:51:18 -05:00
Andreas Hansson
d4273cc9a6 mem: Set the cache line size on a system level
This patch removes the notion of a peer block size and instead sets
the cache line size on the system level.

Previously the size was set per cache, and communicated through the
interconnect. There were plenty checks to ensure that everyone had the
same size specified, and these checks are now removed. Another benefit
that is not yet harnessed is that the cache line size is now known at
construction time, rather than after the port binding. Hence, the
block size can be locally stored and does not have to be queried every
time it is used.

A follow-on patch updates the configuration scripts accordingly.
2013-07-18 08:31:16 -04:00
Xiangyu Dong
4e8ecd7c6f mem: Add cache class destructor to avoid memory leaks
Make valgrind a little bit happier
2013-07-18 08:29:47 -04:00
Brad Beckmann
8e54c93222 ruby: removed the very old double trigger hack
Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2013-07-11 13:56:05 -05:00
Nilay Vaish
1be0098c0b ruby: append transition comment only when in opt/debug 2013-06-28 21:42:27 -05:00
Nilay Vaish
b3980cdb9a ruby: network: remove reconfiguration code
This code seems not to be of any use now. There is no path in the simulator
that allows for reconfiguring the network. A better approach would be to
take a checkpoint and start the simulation from the checkpoint with the new
configuration.
2013-06-28 21:36:37 -05:00
Prakash Ramrakhyani
ac515d7a9b mem: Reorganize cache tags and make them a SimObject
This patch reorganizes the cache tags to allow more flexibility to
implement new replacement policies. The base tags class is now a
clocked object so that derived classes can use a clock if they need
one. Also having deriving from SimObject allows specialized Tag
classes to be swapped in/out in .py files.

The cache set is now templatized to allow it to contain customized
cache blocks with additional informaiton. This involved moving code to
the .hh file and removing cacheset.cc.

The statistics belonging to the cache tags are now including ".tags"
in their name. Hence, the stats need an update to reflect the change
in naming.
2013-06-27 05:49:50 -04:00
Andreas Hansson
0d68d36b9d mem: Remove the cache builder
This patch removes the redundant cache builder class.
2013-06-27 05:49:50 -04:00
Akash Bagdia
7d7ab73862 sim: Add the notion of clock domains to all ClockedObjects
This patch adds the notion of source- and derived-clock domains to the
ClockedObjects. As such, all clock information is moved to the clock
domain, and the ClockedObjects are grouped into domains.

The clock domains are either source domains, with a specific clock
period, or derived domains that have a parent domain and a divider
(potentially chained). For piece of logic that runs at a derived clock
(a ratio of the clock its parent is running at) the necessary derived
clock domain is created from its corresponding parent clock
domain. For now, the derived clock domain only supports a divider,
thus ensuring a lower speed compared to its parent. Multiplier
functionality implies a PLL logic that has not been modelled yet
(create a separate clock instead).

The clock domains should be used as a mechanism to provide a
controllable clock source that affects clock for every clocked object
lying beneath it. The clock of the domain can (in a future patch) be
controlled by a handler responsible for dynamic frequency scaling of
the respective clock domains.

All the config scripts have been retro-fitted with clock domains. For
the System a default SrcClockDomain is created. For CPUs that run at a
different speed than the system, there is a seperate clock domain
created. This domain incorporates the CPU and the associated
caches. As before, Ruby runs under its own clock domain.

The clock period of all domains are pre-computed, such that no virtual
functions or multiplications are needed when calling
clockPeriod. Instead, the clock period is pre-computed when any
changes occur. For this to be possible, each clock domain tracks its
children.
2013-06-27 05:49:49 -04:00
Akash Bagdia
7eccb1b779 config: Remove redundant explicit setting of default clocks
This patch removes the explicit setting of the clock period for
certain instances of CoherentBus, NonCoherentBus and IOCache where the
specified clock is same as the default value of the system clock. As
all the values used are the defaults, there are no performance
changes. There are similar cases where the toL2Bus is set to use the
parent CPU clock which is already the default behaviour.

The main motivation for these simplifications is to ease the
introduction of clock domains.
2013-06-27 05:49:49 -04:00
Andreas Hansson
3b92748937 mem: Tidy up the bridge with const and additional checks
This patch does a bit of tidying up in the bridge code, adding const
where appropriate and also removing redundant checks and adding a few
new ones.

There are no changes to the behaviour of any regressions.
2013-06-27 05:49:49 -04:00
Andreas Hansson
f25ea3fd56 mem: Fix CommMonitor style and response check
This patch fixes the CommMonitor local variable names, and also
introduces a variable to capture if it expects to see a response. The
latter check considers both needsResponse and memInhibitAsserted.
2013-06-27 05:49:49 -04:00
Andreas Hansson
33a8d777ad mem: Align cache timing to clock edges
This patch changes the cache timing calculations such that the results
are aligned to clock edges.

Plenty stats change as a results of this patch.
2013-06-27 05:49:49 -04:00
Andreas Hansson
368f50a0a1 mem: Cycles converted to Ticks in atomic cache accesses
This patch fixes an outstanding issue in the cache timing calculations
where an atomic access returned a time in Cycles, but the port
forwarded it on as if it was in Ticks.

A separate patch will update the regression stats.
2013-06-27 05:49:49 -04:00
Andreas Hansson
f330b3c28d mem: Remove a redundant heap allocation for a snoop packet
This patch changes the updards snoop packet to avoid allocating and
later deleting it. As the code executes in 0 time and the lifetime of
the packet does not extend beyond the block there is no reason to heap
allocate it.
2013-06-27 05:49:49 -04:00
Andreas Hansson
9a1169f3d7 mem: Remove CoherentBus snoop port unused private member
This patch removes an unused member to avoid getting compiler warnings
when using clang.
2013-06-27 05:49:49 -04:00
Nilay Vaish
d8ed1d1a2c ruby: moesi cmp directory: separate actions for external hits
This patch adds separate actions for requests that missed in the local cache
and messages were sent out to get the requested line. These separate actions
are required for differentiating between the hit and miss latencies in the
statistics collected.
2013-06-25 00:32:04 -05:00
Nilay Vaish
128ab50c47 ruby: mesi cmp directory: separate actions for external hits
This patch adds separate actions for requests that missed in the local cache
and messages were sent out to get the requested line. These separate actions
are required for differentiating between the hit and miss latencies in the
statistics collected.
2013-06-25 00:32:03 -05:00
Nilay Vaish
beb6e57c6f ruby: profiler: lots of inter-related changes
The patch started of with removing the global variables from the profiler for
profiling the miss latency of requests made to the cache. The corrresponding
histograms have been moved to the Sequencer. These are combined together when
the histograms are printed. Separate histograms are now maintained for
tracking latency of all requests together, of hits only and of misses only.

A particular set of histograms used to use the type GenericMachineType defined
in one of the protocol files. This patch removes this type. Now, everything
that relied on this type would use MachineType instead. To do this, SLICC has
been changed so that multiple machine types can be declared by a controller
in its preamble.
2013-06-25 00:32:03 -05:00
Nilay Vaish
b3db882dee ruby: remove the three files related to profiling
This patch removes the following three files: RubySlicc_Profiler.sm,
RubySlicc_Profiler_interface.cc and RubySlicc_Profiler_interface.hh.
Only one function prototyped in the file RubySlicc_Profiler.sm. Rest of the
code appearing in any of these files is not in use. Therefore, these files
are being removed.

That one single function, profileMsgDelay(), is being moved to the protocol
files where it is in use. If we need any of these deleted functions, I think
the right way to make them visible is to have the AbstractController class in
a .sm and let the controller state machine inherit from this class. The
AbstractController class can then have the prototypes of these profiling
functions in its definition.
2013-06-24 08:59:08 -05:00
Joel Hestness ext:(%2C%20Nilay%20Vaish%20%3Cnilay%40cs.wisc.edu%3E)
71c6c43110 ruby: MessageBuffer: Remove unused m_size variable
The m_size variable attempted to track m_prio_heap.size(), but it did so
incorrectly due to the functions reanalyzeMessages and reanalyzeAllMessages().
Since this variable is intended to track m_prio_heap.size(), we can simply
replace instances where m_size is referenced with m_prio_heap.size(), which
has the added bonus of removing the need for m_size.

Note: This patch also removes an extraneous DPRINTF format string designator
from reanalyzeAllMessages()

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2013-06-24 06:57:06 -05:00
Lena Olson
94280c7e51 ruby: fix typo in MOESI_CMP_token protocol 2013-06-20 16:20:38 -05:00
Lena Olson
ed234ddec6 ruby: Fix prefetching for MESI_CMP_Directory
Transitions from present on PF_Ifetch were missing, causing a crash when
prefetching is enabled.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2013-06-18 16:59:22 -05:00
Lena Olson
eb1279ff49 ruby: fix slicc compiler to complain about duplicate symbols
Previously, .sm files were allowed to use the same name for a type and a
variable. This is unnecessarily confusing and has some bad side effects, like
not being able to declare later variables in the same scope with the same type.
This causes the compiler to complain and die on things like Address Address.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2013-06-18 16:58:52 -05:00
Lena Olson
7c39d5df7e ruby: restrict Address to being a type and not a variable name
Change all occurrances of Address as a variable name to instead use Addr.
Address is an allowed name in slicc even when Address is also being used as a
type, leading to declarations of "Address Address". While this works, it
prevents adding another field of type Address because the compiler then thinks
Address is a variable name, not type.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2013-06-18 16:58:33 -05:00
Andreas Sandberg
6151c0f7f4 kvm: Use the address finalization code in the TLB
Reuse the address finalization code in the TLB instead of replicating
it when handling MMIO. This patch also adds support for injecting
memory mapped IPR requests into the memory system.
2013-06-18 16:10:22 +02:00
Nilay Vaish
d32ee94231 ruby: remove several unused variables in Profiler
This patch removes per processor cycle count, histogram for filter stats,
histogram for multicasts, histogram for prefetch wait, some function
prototypes that do not have definitions.
2013-06-09 07:30:00 -05:00
Nilay Vaish
27b321f2f7 ruby: remove periodic event from Profiler
The Profiler class does not need an event for dumping statistics
periodically. This is because there is a method for dumping statistics
for all the sim objects periodically. Since Ruby is a sim object, its
statistics are also included.
2013-06-09 07:29:59 -05:00
Nilay Vaish
f59a7af50a ruby: stats: use gem5's stats for cache and memory controllers
This moves event and transition count statistics for cache controllers to
gem5's statistics. It does the same for the statistics associated with the
memory controller in ruby.

All the cache/directory/dma controllers individually collect the event and
transition counts. A callback function, collateStats(), has been added that
is invoked on the controller version 0 of each controller class. This
function adds all the individual controller statistics to a vector
variables. All the code for registering the statistical variables and
collating them is generated by SLICC. The patch removes the files
*_Profiler.{cc,hh} and *_ProfileDumper.{cc,hh} which were earlier used for
collecting and dumping statistics respectively.
2013-06-09 07:29:59 -05:00
Nilay Vaish
38736ce7c3 ruby: remove undefined functions in Address class 2013-06-09 07:29:58 -05:00
Andreas Hansson
3bc4ecdcb4 mem: More descriptive DRAM config names
This patch changes the class names of the variuos DRAM configurations
to better reflect what memory they are based on. The speed and
interface width is now part of the name, and also the alias that is
used to select them on the command line.

Some minor changes are done to the actual parameters, to better
reflect the named configurations. As a result of these changes the
regressions change slightly and the stats will be bumped in a separate
patch.
2013-05-30 12:54:14 -04:00
Andreas Hansson
83d99aebb1 mem: Add bytes per activate DRAM controller stat
This patch adds a histogram to track how many bytes are accessed in an
open row before it is closed. This metric is useful in characterising
a workload and the efficiency of the DRAM scheduler. For example, a
DDR3-1600 device requires 44 cycles (tRC) before it can activate
another row in the same bank. For a x32 interface (8 bytes per cycle)
that means 8 x 44 = 352 bytes must be transferred to hide the
preparation time.
2013-05-30 12:54:13 -04:00
Andreas Hansson
d82bffd297 mem: Add static latency to the DRAM controller
This patch adds a frontend and backend static latency to the DRAM
controller by delaying the responses. Two parameters expressing the
frontend and backend contributions in absolute time are added to the
controller, and the appropriate latency is added to the responses when
adding them to the (infinite) queued port for sending.

For writes and reads that hit in the write buffer, only the frontend
latency is added. For reads that are serviced by the DRAM, the static
latency is the sum of the pipeline latencies of the entire frontend,
backend and PHY. The default values are chosen based on having roughly
10 pipeline stages in total at 500 MHz.

In the future, it would be sensible to make the controller use its
clock and convert these latencies (and a few of the DRAM timings) to
cycles.
2013-05-30 12:54:12 -04:00
Andreas Hansson
7da851d1a8 mem: Spring cleaning of MSHR and MSHRQueue
This patch does some minor tidying up of the MSHR and MSHRQueue. The
clean up started as part of some ad-hoc tracing and debugging, but
seems worthwhile enough to go in as a separate patch.

The highlights of the changes are reduced scoping (private) members
where possible, avoiding redundant new/delete, and constructor
initialisation to please static code analyzers.
2013-05-30 12:54:11 -04:00
Andreas Hansson
42191522cc mem: Fix MSHR print format
This patch fixes an incorrect print format string by adding an
additional string element.
2013-05-30 12:54:09 -04:00
Andreas Hansson
7e13c4d046 mem: Make returning snoop responses occupy response layer
This patch introduces a mirrored internal snoop port to facilitate
easy addition of flow control for the snoop responses that are turned
into normal responses on their return. To perform this, the slave
ports of the coherent bus are wrapped in internal master ports that
are passed as the source ports to the response layer in question.

As a result of this patch, there is more contention for the response
resources, and as such system performance will decrease slightly.

A consequence of the mirrored internal port is that the port the bus
tells to retry (the internal one) and the port actually retrying (the
mirrored) one are not the same. Thus, the existing check in tryTiming
is not longer correct. In fact, the test is redundant as the layer is
only in the retry state while calling sendRetry on the waiting port,
and if the latter does not immediately call the bus then the retry
state is left. Consequently the check is removed.
2013-05-30 12:54:02 -04:00
Andreas Hansson
2308f812ef mem: Make the buses multi layered
This patch makes the buses multi layered, and effectively creates a
crossbar structure with distributed contention ports at the
destination ports. Before this patch, a bus could have a single
request, response and snoop response in flight at any time, and with
these changes there can be as many requests as connected slaves (bus
master ports), and as many responses as connected masters (bus slave
ports).

Together with address interleaving, this patch enables us to create
high-throughput memory interconnects, e.g. 50+ GByte/s.
2013-05-30 12:54:01 -04:00
Andreas Hansson
e82996d9da mem: Separate the two snoop response cases in the bus
This patch makes the flow control and state updates of the coherent
bus more clear by separating the two cases, i.e. forward as a snoop
response, or turn it into a normal response.

With this change it is also more clear what resources are being
occupied, and that we effectively bypass the busy check for the second
case. As a result of the change in resource usage some stats change.
2013-05-30 12:54:00 -04:00
Andreas Hansson
cb62d39835 mem: Tidy up a few variables in the bus
This patch does some minor housekeeping on the bus code, removing
redundant code, and moving the extraction of the destination id to the
top of the functions using it.
2013-05-30 12:53:59 -04:00
Uri Wiener
91f7b065a9 mem: Add basic stats to the buses
This patch adds a basic set of stats which are hard to impossible to
implement using only communication monitors, and are needed for
insight such as bus utilization, transactions through the bus etc.

Stats added include throughput and transaction distribution, and also
a two-dimensional vector capturing how many packets and how much data
is exchanged between the masters and slaves connected to the bus.
2013-05-30 12:53:58 -04:00
Andreas Hansson
e1e73c5f39 mem: Use unordered set in bus request tracking
This patch changes the set used to track outstanding requests to an
unordered set (part of C++11 STL). There is no need to maintain the
order, and hopefully there might even be a small performance benefit.
2013-05-30 12:53:57 -04:00
Andreas Hansson
82397921a5 mem: Check for waiting state in bus draining
This patch fixes a bug in the bus where the bus transitions from busy
to idle and still has a port that is waiting for a retry from a peer.
2013-05-30 12:53:57 -04:00
Andreas Hansson
bf6291460d mem: Add a LPDDR3-1600 configuration
This patch adds a typical (leaning towards fast) LPDDR3 configuration
based on publically available data. As expected, it looks very similar
to the LPDDR2-S4 configuration, only with a slightly lower burst time.
2013-05-30 12:53:56 -04:00
Andreas Hansson
ce1ad84abd mem: Adapt the LPDDR2 to match a single x32 channel
This patch adapts the existing LPDDR2 configuration to make use of the
multi-channel functionality. Thus, to get a x64 interface two
controllers should be instantiated using the makeMultiChannel method.

The page size and ranks are also adapted to better suit with a typical
LPDDR2 part.
2013-05-30 12:53:55 -04:00
Andreas Hansson
88aa7755f4 mem: Avoid explicitly zeroing the memory backing store
This patch removes the explicit memset as it is redundant and causes
the simulator to touch the entire space, forcing the host system to
allocate the pages.

Anonymous pages are mapped on the first access, and the page-fault
handler is responsible for zeroing them. Thus, the pages are still
zeroed, but we avoid touching the entire allocated space which enables
us to use much larger memory sizes as long as not all the memory is
actually used.
2013-05-30 12:53:54 -04:00
Malek Musleh
64af621cc6 ruby: slicc: fix error msg in TypeFieldMemberAST.py 2013-05-21 11:57:14 -05:00
Nilay Vaish
4ef466cc8a ruby: moesi hammer: cosmetic changes
Updates copyright years, removes space at the end of lines, shortens
variable names.
2013-05-21 11:32:45 -05:00
Nilay Vaish
09d5bc7e6f ruby: mesi cmp directory: cosmetic changes
Updates copyright years, removes space at the end of lines, shortens
variable names.
2013-05-21 11:32:38 -05:00
Nilay Vaish
bd3d1955da ruby: moesi cmp token: cosmetic changes
Updates copyright years, removes space at the end of lines, shortens
variable names.
2013-05-21 11:32:24 -05:00
Nilay Vaish
e7ce518168 ruby: moesi cmp directory: cosmetic changes
Updates copyright years, removes space at the end of lines, shortens
variable names.
2013-05-21 11:32:15 -05:00
Nilay Vaish ext:(%2C%20Malek%20Musleh%20%3Cmalek.musleh%40gmail.com%3E)
59a7abff29 ruby: add stats to .sm files, remove cache profiler
This patch changes the way cache statistics are collected in ruby.

As of now, there is separate entity called CacheProfiler which holds
statistical variables for caches. The CacheMemory class defines different
functions for accessing the CacheProfiler. These functions are then invoked
in the .sm files. I find this approach opaque and prone to error. Secondly,
we probably should not be paying the cost of a function call for recording
statistics.

Instead, this patch allows for accessing statistical variables in the
.sm files. The collection would become transparent. Secondly, it would happen
in place, so no function calls. The patch also removes the CacheProfiler class.

--HG--
rename : src/mem/slicc/ast/InfixOperatorExprAST.py => src/mem/slicc/ast/OperatorExprAST.py
2013-05-21 11:31:31 -05:00
Mitch Hayenga
b222ba2fd3 sim: Fix two bugs relating to software caching of PageTable entries.
The existing implementation can read uninitialized data or stale information
from the cached PageTable entries.

1) Add a valid bit for the cache entries.  Simply using zero for the virtual
address to signify invalid entries is not sufficient.  Speculative, wrong-path
accesses frequently access page zero.  The current implementation would return
a uninitialized TLB entry when address zero was accessed and the PageTable
cache entry was invalid.

2) When unmapping/mapping/remaping a page, invalidate the corresponding
PageTable cache entry if one already exists.
2013-04-23 09:47:52 -04:00
Nilay Vaish
95eebf9e5e ruby: mesi coherence protocol: remove unused state M_MB 2013-04-23 00:03:07 -05:00
Nilay Vaish
aa86800e7a ruby: patch checkpoint restore with garnet
Due to recent changes to clocking system in Ruby and the way Ruby restores
state from a checkpoint, garnet was failing to run from a checkpointed state.
The problem is that Ruby resets the time to zero while warming up the caches.
If any component records a local copy of the time (read calls curCycle())
before the simulation has started, then that component will not operate until
that time is reached. In the context of this particular patch, the Garnet
Network class calls curCycle() at multiple places. Any non-operational
component can block in requests in the memory system, which the system
interprets as a deadlock. This patch makes changes so that Garnet can
successfully run from checkpointed state.

It adds a globally visible time at which the actual execution started. This
time is initialized in RubySystem::startup() function. This variable is only
meant for components with in Ruby. This replaces the private variable that
was maintained within Garnet since it is not possible to figure out the
correct time when the value of this variable can be set.

The patch also does away with all cases where curCycle() is called with in
some Ruby component before the system has actually started executing. This
is required due to the quirky manner in which ruby restores from a checkpoint.
2013-04-23 00:03:02 -05:00
Andreas Hansson
e23e3bea8b mem: Address mapping with fine-grained channel interleaving
This patch adds an address mapping scheme where the channel
interleaving takes place on a cache line granularity. It is similar to
the existing RaBaChCo that interleaves on a DRAM page, but should give
higher performance when there is less locality in the address
stream.
2013-04-22 13:20:34 -04:00
Andreas Hansson
e61799aa7c mem: More descriptive enum names for address mapping
This patch changes the slightly ambigious names used for the address
mapping scheme to be more descriptive, and actually spell out what
they do. With this patch we also open up for adding more flavours of
open- and close-type mappings, i.e. interleaving across channels with
the open map.
2013-04-22 13:20:33 -04:00
Andreas Hansson
a35d3ff167 mem: Add a WideIO DRAM configuration
This patch adds a WideIO 200 MHz configuration that can be used as a
baseline to compare with DDRx and LPDDRx. Note that it is a single
channel and that it should be replicated 4 times. It is based on
publically available information and attempts to capture an envisioned
8 Gbit single-die part (i.e. without TSVs).
2013-04-22 13:20:33 -04:00
Uri Wiener
a8fbfefb5e mem: Adding verbose debug output in the memory system
This patch provides useful printouts throughut the memory system. This
includes pretty-printed cache tags and function call messages
(call-stack like).
2013-04-22 13:20:33 -04:00
Andreas Hansson
9929e884b6 mem: Replace check with panic where inhibited should not happen
This patch changes the SimpleTimingPort and RubyPort to panic on
inhibited requests as this should never happen in either of the
cases. The SimpleTimingPort is only used for the I/O devices PIO port
and the DMA devices config port and should thus never see an inhibited
request. Similarly, the SimpleTimingPort is also used for the
MessagePort in x86, and there should also not be any cases where the
port sees an inhibited request.
2013-04-22 13:20:33 -04:00
Dam Sunwoo
e8381142b0 sim: separate nextCycle() and clockEdge() in clockedObjects
Previously, nextCycle() could return the *current* cycle if the current tick was
already aligned with the clock edge. This behavior is not only confusing (not
quite what the function name implies), but also caused problems in the
drainResume() function. When exiting/re-entering the sim loop (e.g., to take
checkpoints), the CPUs will drain and resume. Due to the previous behavior of
nextCycle(), the CPU tick events were being rescheduled in the same ticks that
were already processed before draining. This caused divergence from runs that
did not exit/re-entered the sim loop. (Initially a cycle difference, but a
significant impact later on.)

This patch separates out the two behaviors (nextCycle() and clockEdge()),
uses nextCycle() in drainResume, and uses clockEdge() everywhere else.
Nothing (other than name) should change except for the drainResume timing.
2013-04-22 13:20:31 -04:00
Nilay Vaish
03c60f005e ruby: moesi cmp directory: add copyright notice 2013-04-17 16:06:58 -05:00
Joel Hestness
1583056de8 Ruby: Fix RubyPort evict packet memory leak
When using the o3 or inorder CPUs with many Ruby protocols, the caches may
need to forward invalidations to the CPUs. The RubyPort was instantiating a
packet to be sent to the CPUs to signal the eviction, but the packets were
not being freed by the CPUs. Consistent with the classic memory model, stack
allocate the packet and heap allocate the request so on
ruby_eviction_callback() completion, the packet deconstructor is called, and
deletes the request (*Note: stack allocating the request causes double
deletion, since it will be deleted in the packet destructor). This results in
the least memory allocations without memory errors.
2013-04-09 16:25:30 -05:00
Joel Hestness
46d4b71aa2 Ruby: Delete packet requests during warmup
When warming up caches in Ruby, the CacheRecorder sends fetch requests into
Ruby Sequencers with packet types that require responses. Since responses are
never generated for these CacheRecorder requests, the requests are not deleted
in the packet destructor called from the Ruby hit callback. Free the request.
2013-04-09 16:25:29 -05:00
Joel Hestness
e98c3c227d Ruby: Add field to slicc machine for generic type
This allows you to have (i.e.) an L2 cache that is not named "L2Cache"
but is still a GenericMachineType_L2Cache. This is particularly
helpful if the protocol has multiple L2 controllers.
2013-04-09 16:25:29 -05:00
Joel Hestness
b936619ab4 Ruby: Order profilers based on version
When Ruby stats are printed for events and transitions, they include stats
for all of the controllers of the same type, but they are not necessarily
printed in order of the controller ID "version", because of the way the
profilers were added to the profiler vector. This patch fixes the push order
problem so that the stats are printed in ascending order 0->(# controllers),
so statistics parsers may correctly assume the controller to which the stats
belong.
2013-04-09 16:25:29 -05:00
Jason Power
88d34665d0 Ruby: More descriptive message buffer connection fatal
When connecting message buffers between Ruby controllers, it is
easy to mistakenly connect multiple controllers to the same message
buffer. This patch prints a more descriptive fatal message than the
previous assert statement in order to facilitate easier debugging.
2013-04-09 16:15:06 -05:00
Jason Power
19cc9fc6bd Ruby: Fix typo in Slicc if-statement AST error
The error in the SLICC code was hidden by the python error in SLICC parser
before this patch
2013-04-09 16:12:42 -05:00
Joel Hestness
3b02210713 Ruby System, Cache Recorder: Use delete [] for trace vars
The cache trace variables are array allocated uint8_t* in the RubySystem and
the Ruby CacheRecorder, but the code used delete to free the memory, resulting
in Valgrind memory errors. Change these deletes to delete [] to get rid of the
errors.
2013-04-07 20:31:15 -05:00
Mitch Hayenga
4920f0d7e5 mem: Fix cache latency bug
Fixes a latency calculation bug for accesses during a cache line fill.

Under a cache miss, before the line is filled, accesses to the cache are
associated with a MSHR and marked as targets.  Once the line fill completes,
MSHR target packets pay an additional latency of
"responseLatency + busSerializationLatency".  However, the "whenReady"
field of the cache line is only set to an additional delay of
"busSerializationLatency".  This lacks the responseLatency component of
the fill.  It is possible for accesses that occur on the cycle of
(or briefly after) the line fill to respond without properly paying the
responseLatency.  This also creates the situation where two accesses to the
same address may be serviced in an order opposite of how they were received
by the cache.  For stores to the same address, this means that although the
cache performs the stores in the order they were received, acknowledgements
may be sent in a different order.

Adding the responseLatency component to the whenReady field preserves the
penalty that should be paid and prevents these ordering issues.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2013-03-27 18:36:09 -05:00
Rene de Jong
87089175cc mem: Cancel cache retry event when blocking port
This patch solves the corner case scenario where the sendRetryEvent could be
scheduled twice, when an io device stresses the IOcache in the system. This
should not be possible in the cache system.
2013-03-26 14:46:51 -04:00
Andreas Hansson
93a8423dea mem: Separate waiting for the bus and waiting for a peer
This patch splits the retryList into a list of ports that are waiting
for the bus itself to become available, and a map that tracks the
ports where forwarding failed due to a peer not accepting the
packet. Thus, when a retry reaches the bus, it can be sent to the
appropriate port that initiated that transaction.

As a consequence of this patch, only ports that are really ready to go
will get a retry, thus reducing the amount of redundant failed
attempts. This patch also makes it easier to reason about the order of
servicing requests as the ports waiting for the bus are now clearly
FIFO and much easier to change if desired.
2013-03-26 14:46:47 -04:00
Andreas Hansson
362f6f1a16 mem: Introduce a variable for the retrying port
This patch introduces a variable to keep track of the retrying port
instead of relying on it being the front of the retryList.

Besides the improvement in readability, this patch is a step towards
separating out the two cases where a port is waiting for the bus to be
free, and where the forwarding did not succeed and the bus is waiting
for a retry to pass on to the original initiator of the transaction.

The changes made are currently such that the regressions are not
affected. This is ensured by always prioritizing the currently
retrying port and putting it back at the front of the retry list.
2013-03-26 14:46:46 -04:00
Andreas Hansson
7a57b1bce0 mem: Add optional request flags to the packet trace
This patch adds an optional flags field to the packet trace to encode
the request flags that contain information about whether the request
is (un)cacheable, instruction fetch, preftech etc.
2013-03-26 14:46:44 -04:00
Nilay Vaish
b2c8c50f17 ruby: slicc: set sender, receiver clock objs for optional queue 2013-03-22 17:21:23 -05:00
Nilay Vaish
e85b556d70 ruby: message buffer: correct previous errors
A recent set of patches added support for multiple clock domains to ruby.
I had made some errors while writing those patches. The sender was using
the receiver side clock while enqueuing a message in the buffer. Those
errors became visible while creating (or restoring from) checkpoints. The
errors also become visible when a multi eventq scenario occurs.
2013-03-22 17:21:22 -05:00
Nilay Vaish
47c8cb72fc ruby: message buffer: remove _ptr from some variables
The names were getting too long.
2013-03-22 15:53:27 -05:00
Nilay Vaish
6465cf5824 ruby: message buffer node: used Tick in place of Cycles
The message buffer node used to keep time in terms of Cycles. Since the
sender and the receiver can have different clock periods, storing node
time in cycles requires some conversion. Instead store the time directly
in Ticks.
2013-03-22 15:53:26 -05:00
Nilay Vaish
39e9445468 ruby: consumer: avoid using receiver side clock
A set of patches was recently committed to allow multiple clock domains
in ruby. In those patches, I had inadvertently made an incorrect use of
the clocks. Suppose object A needs to schedule an event on object B. It
was possible that A accesses B's clock to schedule the event. This is not
possible in actual system. Hence, changes are being to the Consumer class
so as to avoid such happenings. Note that in a multi eventq simulation,
this can possibly lead to an incorrect simulation.

There are two functions in the Consumer class that are used for scheduling
events. The first function takes in the relative delay over the current time
as the argument and adds the current time to it for scheduling the event.
The second function takes in the absolute time (in ticks) for scheduling the
event. The first function is now being moved to protected section of the
class so that only objects of the derived classes can use it. All other
objects will have to specify absolute time while scheduling an event
for some consumer.
2013-03-22 15:53:26 -05:00
Nilay Vaish
28005a7626 ruby: remove unsued profile functions 2013-03-22 15:53:25 -05:00
Nilay Vaish
89bb826079 ruby: keep histogram of outstanding requests in seq
The histogram for tracking outstanding counts per cycle is maintained
in the profiler. For a parallel implementation of the memory system, we
need that this histogram is maintained locally. Hence it will now be
kept in the sequencer itself. The resulting histograms will be merged
when the stats are printed.
2013-03-22 15:53:25 -05:00
Nilay Vaish
870d545788 slicc: remove check if the L1Cache has a sequencer 2013-03-22 15:53:24 -05:00
Nilay Vaish
8573a69d8f ruby: move stall and wakeup functions to AbstractController
These functions are currently implemented in one of the files related to Slicc.
Since these are purely C++ functions, they are better suited to be in the base
class.
2013-03-22 15:53:24 -05:00
Nilay Vaish
eccc86e809 ruby: connect two controllers using only message buffers
This patch modifies ruby so that two controllers can be connected to each
other with only message buffers in between. Before this patch, all the
controllers had to be connected to the network  for them to communicate
with each other. With this patch, one can have protocols where a controller
is not connected to the network, but communicates with another controller
through a message buffer.
2013-03-22 15:53:23 -05:00
Nilay Vaish
5aa43e130a ruby: convert Topology to regular class
The Topology class in Ruby does not need to inherit from SimObject class.
This patch turns it into a regular class. The topology object is now created
in the constructor of the Network class. All the parameters for the topology
class have been moved to the network class.
2013-03-22 15:53:23 -05:00
Nilay Vaish
2d50127642 ruby: network: move routers from topology to network 2013-03-22 15:53:22 -05:00
Andreas Hansson
c01c5e971b mem: Fix missing delete of packet in DRAM access
This patch fixes a memory leak caused by not deleting packets that
require no response.
2013-03-18 05:22:45 -04:00
Nilay Vaish
dc37b03439 ruby: set: corrects csprintf() call introduced by 7d95b650c9b6 2013-03-15 16:28:08 -05:00
Andreas Hansson
92e973b310 ruby: Fix gcc 4.8 maybe-uninitialized compilation error
This patch fixes the one-and-only gcc 4.8 compilation error, being a
warning about "maybe uninitialized" in Orion.
2013-03-07 05:55:02 -05:00
Nilay Vaish
c061819890 ruby: remove the functional copy of memory in se mode
This patch removes the functional copy of the memory that was maintained in
the se mode. Now ruby itself will provide the data.
2013-03-06 21:53:57 -06:00
Nilay Vaish
e8802fa127 ruby: garnet: fixed: implement functional access 2013-03-06 21:53:16 -06:00
Blake Hechtman ext:(%2C%20Nilay%20Vaish%20%3Cnilay%40cs.wisc.edu%3E)
af8eb67fb4 ruby: fixes functional writes to RubyRequest
The functional write code was assuming that all writes are block sized,
which may not be true for Ruby Requests. This bug can lead to a buffer
overflow.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2013-03-02 23:12:55 -06:00
Andreas Hansson
e5bcb30756 mem: Add check if SimpleDRAM nextReqEvent is scheduled
This check covers a case where a retry is called from the SimpleDRAM
causing a new request to appear before the DRAM itself schedules a
nextReqEvent. By adding this check, the event is not scheduled twice.
2013-03-01 13:20:33 -05:00