Commit graph

9738 commits

Author SHA1 Message Date
Andreas Sandberg
63dae28703 base: Make the Python module loader PEP302 compliant
The custom Python loader didn't comply with PEP302 for two reasons:

 * Previously, we would overwrite old modules on name
   conflicts. PEP302 explicitly states that: "If there is an existing
   module object named 'fullname' in sys.modules, the loader must use
   that existing module".

 * The "__package__" attribute wasn't set. PEP302: "The __package__
   attribute must be set."

This changeset addresses both of these issues.
2013-06-03 13:51:03 +02:00
Andreas Sandberg
d989a3ad50 config: Add missing CPUs to --restore-with-cpu
The --restore-with-cpu option didn't use CpuConfig.cpu_names() to
determine which CPU names are valid, instead it used a static list of
known CPU names. This changeset makes the option parsing code use the
CPU list from the CpuConfig module instead.
2013-06-03 13:40:05 +02:00
Andreas Sandberg
c2ec232920 kvm: Allow architectures to override the cycle accounting mechanism
Some architectures have special registers in the guest that can be
used to do cycle accounting. This is generally preferrable since the
prevents the guest from seeing a non-monotonic clock. This changeset
adds a virtual method, getHostCycles(), that the architecture-specific
code can override to implement this functionallity. The default
implementation uses the hwCycles counter.
2013-06-03 13:39:11 +02:00
Andreas Sandberg
15f81b6ed9 kvm: Add handling of EAGAIN when creating timers
timer_create can apparently return -1 and set errno to EAGAIN if the
kernel suffered a temporary failure when allocating a timer. This
happens from time to time, so we need to handle it.
2013-06-03 13:38:59 +02:00
Andreas Sandberg
743f80712e sim: Add debug output when executing pseudo-instructions 2013-06-03 13:21:21 +02:00
Andreas Sandberg
2b65fce5d9 kvm: Add a call to thread->startup() in startup()
It is now required to initialize the thread context by calling
startup() on it. Failing to do so currently causes decoder in
x86-based CPUs to get very confused when restoring from checkpoints.
2013-06-03 12:36:56 +02:00
Andreas Sandberg
5e60f87aa3 dev: Add support for disabling ticking and the divider in MC146818
Some Linux versions disable updates (regB.set = 1) to prevent the chip
from updating its internal state while the OS is updating it. Support
for this was already there, this patch merely disables the check in
writeReg that prevented it from being enabled. The patch also includes
support for disabling the divider, which is used to control when clock
updates should start after setting the internal RTC state.

These changes are required to boot most vanilla Linux distributions
that update the RTC settings at boot.
2013-06-03 12:28:52 +02:00
Andreas Sandberg
14b8a17f28 dev: Clean up MC146818 register (A & B) handling
Rewrite reg A & B handling to use the bitunion stuff instead of bit
masking. Add better error messages when the kernel tries to enable
unsupported stuff.
2013-06-03 12:28:41 +02:00
Andreas Hansson
74553c7d3f stats: Update the stats to reflect bus and memory changes
This patch updates the stats to reflect the addition of the bus stats,
and changes to the bus layers. In addition it updates the stats to
match the addition of the static pipeline latency of the memory
conotroller and the addition of a stat tracking the bytes per
activate.
2013-05-30 12:54:18 -04:00
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
4d7d8393ed cpu: Prune the stale TraceCPU
This patch prunes the TraceCPU as the code is stale and the
functionality that it provided can now be achieved with the TrafficGen
using its trace playback mode.

The TraceCPU was able to play back pre-recorded memory traces of a few
different formats, and to achieve this level of flexibility with the
TrafficGen, use the util/encode_packet_trace (with suitable
modifications) to create a protobuf trace off-line.
2013-05-30 12:54:09 -04:00
Sascha Bischoff
6f4be9bd4c cpu: Check that minimum TrafficGen period is less than max period
Add a check which ensures that the minumum period for the LINEAR and
RANDOM traffic generator states is less than or equal to the maximum
period. If the minimum period is greater than the maximum period a
fatal is triggered.
2013-05-30 12:54:08 -04:00
Sascha Bischoff
04ccc79134 cpu: Fix bug when reading in TrafficGen state transitions
This patch fixes a bug with the traffic generator which occured when
reading in the state transitions from the configuration
file. Previously, the size of the vector which stored the transitions
was used to get the size of the transitions matrix, rather than using
the number of states. Therefore, if there were more transitions than
states, i.e. some transitions has a probability of less than 1, then
the traffic generator would fatal when trying to check the
transitions.

This issue has been addressed by using the number of input states,
rather then the number of transitions.
2013-05-30 12:54:07 -04:00
Andreas Hansson
fc09bc8678 cpu: Add request elasticity to the traffic generator
This patch adds an optional request elasticity to the traffic
generator, effectievly compensating for it in the case of the linear
and random generators, and adding it in the case of the trace
generator. The accounting is left with the top-level traffic
generator, and the individual generators do the necessary math as part
of determining the next packet tick.

Note that in the linear and random generators we have to compensate
for the blocked time to not be elastic, i.e. without this patch the
aforementioned generators will slow down in the case of back-pressure.
2013-05-30 12:54:06 -04:00
Andreas Hansson
4931414ca7 cpu: Block traffic generator when requests have to retry
This patch changes the queued port for a conventional master port and
stalls the traffic generator when requests are not immediately
accepted. This is a first step to allowing elasticity in the injection
of requests.

The patch also adds stats for the sent packets and retries, and
slightly changes how the nextPacketTick and getNextPacket
interact. The advancing of the trace is now moved to getNextPacket and
nextPacketTick is only responsible for answering the question when the
next packet should be sent.
2013-05-30 12:54:05 -04:00
Andreas Hansson
c9c35da934 cpu: Move traffic generator sending out of generator states
This patch moves the responsibility for sending packets out of the
generator states and leaves it with the top-level traffic
generator. The main aim of this patch is to enable a transition to
non-queued ports, i.e. with send/retry flow control, and to do so it
is much more convenient to not wrap the port interactions and instead
leave it all local to the traffic generator.

The generator states now only govern when they are ready to send
something new, and the generation of the packets to send. They thus
have no knowledge of the port that is used.
2013-05-30 12:54:04 -04:00
Andreas Hansson
ba11a02cf2 cpu: Fold together the StateGraph and the TrafficGen
This patch simplifies the object hierarchy of the traffic generator by
getting rid of the StateGraph class and folding this functionality
into the traffic generator itself.

The main goal of this patch is to facilitate upcoming changes by
reducing the number of affected layers.
2013-05-30 12:54:03 -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
Andreas Hansson
cc8911261e util: Auto generate the packet proto definitions
This patch simplifies the usage of the packet trace encoder/decoder by
attempting to automatically generating the packet proto definitions in
case they cannot be found.
2013-05-30 12:53:53 -04:00
Andreas Hansson
4c7a283e55 base: Avoid size limitation on protobuf coded streams
This patch changes how the streams are created to avoid the size
limitation on the coded streams. As we only read/write a single
message at a time, there is never any message larger than a few
bytes. However, the coded stream eventually complains that its
internal counter reaches 64+ MByte if the total file size exceeds this
value.

Based on suggestions in the protobuf discussion forums, the coded
stream is now created for every message that is read/written. The
result is that the internal byte count never goes about tens of bytes,
and we can read/write any size file that the underlying file I/O can
handle.
2013-05-30 12:53:53 -04:00
Andreas Hansson
d1a43d83da cpu: Make hash struct instead of class to please clang
This patch changes the type of the hash function for BasicBlockRanges
to match the original definition of the templatized type. Without
this, clang raises a warning and combined with the "-Werror" flag this
causes compilation to fail.
2013-05-30 12:53:52 -04:00
Malek Musleh
64af621cc6 ruby: slicc: fix error msg in TypeFieldMemberAST.py 2013-05-21 11:57:14 -05:00
Nilay Vaish
af2e83c7f1 x86, regressions: updates stats
This is due to op class, function call, walker patches.
2013-05-21 11:41:27 -05:00
Gedare Bloom
22b60c57e6 x86: Squash outstanding walks when instructions are squashed.
This is the x86 version of the ARM changeset baa17ba80e06. In case an
instruction has been squashed by the o3 cpu, this patch allows page
table walker to avoid carrying out a pending translation that the
instruction requested for.
2013-05-21 11:40:11 -05:00
Nilay Vaish
30fe807316 x86: mark instructions for being function call/return
Currently call and return instructions are marked as IsCall and IsReturn. Thus, the
branch predictor does not use RAS for these instructions. Similarly, the number of
function calls that took place is recorded as 0. This patch marks these instructions
as they should be.
2013-05-21 11:34:41 -05:00
Nilay Vaish
fba40864aa x86: add op class for int and fp microops in isa description
Currently all the integer microops are marked as IntAluOp and the floating
point microops are marked as FloatAddOp. This patch adds support for marking
different microops differently. Now IntMultOp, IntDivOp, FloatDivOp,
FloatMultOp, FloatCvtOp, FloatSqrtOp classes will be used as well. This will
help in providing different latencies for different op class.
2013-05-21 11:33:57 -05:00
Nilay Vaish
5b49c3d255 stats: updates statistics for ruby regressions 2013-05-21 11:32:57 -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
9bc75e3c58 configs: ruby: pass the option use_map to directory controller
The option was not being passed to directory controllers for the protocols
MOESI_CMP_token and MOESI_CMP_directory. This was resulting in an error
while instantiating the directory controller as it tries to access the
wrong type of memory.
2013-05-21 11:32:08 -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
Anthony Gutierrez
d3c33d91b6 cpu: remove local/globalHistoryBits params from branch pred
having separate params for the local/globalHistoryBits and the
local/globalPredictorSize can lead to inconsistencies if they
are not carefully set. this patch dervies the number of bits
necessary to index into the local/global predictors based on
their size.

the value of the localHistoryTableSize for the ARM O3 CPU has been
increased to 1024 from 64, which is more accurate for an A15 based
on some correlation against A15 hardware.
2013-05-14 18:39:47 -04:00
Andreas Sandberg
4e52789c6d kvm: Add support for disabling coalesced MMIO
Add the option useCoalescedMMIO to the BaseKvmCPU. The default
behavior is to disable coalesced MMIO since this hasn't been heavily
tested.
2013-05-14 16:02:45 +02:00
Andreas Sandberg
3ba93822cc kvm: Dump state before panic in KVM exit handlers 2013-05-14 15:59:43 +02:00
Andreas Sandberg
98483ba858 kvm: Fix the memory interface used by KVM
The CpuPort class was removed before the KVM patches were committed,
which means that the KVM interface currently doesn't compile. This
changeset adds the BaseKvmCPU::KVMCpuPort class which derives from
MasterPort. This class is used on the data and instruction ports
instead of the old CpuPort.
2013-05-14 15:56:04 +02:00