Commit graph

10111 commits

Author SHA1 Message Date
Andreas Hansson
62fe81e9c1 cpu: Make CPU and ThreadContext getters const
This patch merely tidies up the CPU and ThreadContext getters by
making them const where appropriate.
2014-03-07 15:56:23 -05:00
Geoffrey Blake
c4a8e5c36c arm: Handle functional TLB walks properly
The table walker code currently accounts for two types of walks,
Atomic and Timing, and treats them differently. Atomic walks keep a
single instance of WalkerState around for all walks to use in
currState. Timing mode keeps a queue of in-flight WalkerStates and
maintains currState as NULL between walks.

If a functional walk is done during Timing mode, it is treated as an
atomic walk and either creates a persistent WalkerState if in between
Timing walks, or stomps an existing currState for an in-progress
Timing walk.

This patch distinguishes functional walks as being able to exist at
any time and sets up a temporary WalkerState for its exclusive use and
then cleans up when finished, leaving any in progress Atomic or Timing
walks undisturbed.
2014-03-07 15:56:23 -05:00
Prakash Ramrakhyani
e88cffb30a mem: Fix incorrect assert failure in the Cache
This patch fixes an assert condition that is not true at all
times. There are valid situations that arise in dual-core
dual-workload runs where the assert condition is false. The function
call following the assert however needs to be called only when the
condition is true (a block cannot be invalidated in the tags structure
if has not been allocated in the structure, and the tempBlock is never
allocated). Hence the 'assert' has been replaced with an 'if'.
2014-03-07 15:56:23 -05:00
Radhika Jagtap
c446dc40bd mem: Edit proto Packet and enhance the python script
This patch changes the decode script to output the optional fields of
the proto message Packet, namely id and flags. The flags field is set
by the communication monitor.

The id field is useful for CPU trace experiments, e.g. linking the
fetch side to decode side. It had to be renamed because it clashes
with a built in python function id() for getting the "identity" of an
object.

This patch also takes a few common function definitions out from the
multiple scripts and adds them to a protolib python module.
2014-03-07 15:56:23 -05:00
Mitch Hayenga
7084e31341 scons: Fix clang version identification for OSX
The version string may have additional trailing information
2014-03-07 15:56:23 -05:00
Stephan Diestelhorst
45677ffa97 misc: Add panic_if / fatal_if / chatty_assert
This snippet can be used to replace if + {panics, fatals, asserts} constructs.
The idea is to have both the condition checking and a verbose printout in a single statement.  The interface is as follows:

panic_if(foo != bar, "These should be equal: foo %i bar %i", foo, bar);
fatal_if(foo != bar, "These should be equal: foo %i bar %i", foo, bar);
chatty_assert(foo == bar, "These should be equal: foo %i bar %i", foo, bar);
2014-03-07 15:56:23 -05:00
Mitch Hayenga
b9a9d99b22 scons: Fixes uninitialized warnings issued by clang
Small fixes to appease recent clang versions.
2014-03-07 15:56:23 -05:00
Stephan Diestelhorst
bef2086f5b arm: Fix uninitialised warning with gcc 4.8
Small fix for a warning that prevents compilation with gcc 4.8.1 due
to detecting that a variable might be uninitialised. The fix is to
assign a safe default.
2014-03-07 15:56:23 -05:00
Ali Saidi
bf39a475fe mem: Wakeup sleeping CPUs without caches on LLSC
For systems without caches, the LLSC code does not get snoops for
wake-ups. We add the LLSC code in the abstract memory to do the job
for us.
2014-03-07 15:56:23 -05:00
Andreas Sandberg
f4a897d8e3 sim: Schedule the global sync event at curTick() + simQuantum
The global synchronization event used to be scheduled at
simQuantum. This prevented repeated entries into gem5 from Python as
it can be scheduled in the past. This changeset ensures that the first
global synchronization happens at curTick() + simQuantum instead.
2014-03-06 15:59:53 +01:00
Andreas Sandberg
be246cef62 x86: Setup correct TSL/TR segment attributes on INIT
The TSL/LDT & TR/TSS segments didn't contain valid attributes. This
caused problems when transfering the state into KVM where invalid
state is a no-go. Fixup the attributes with values from AMD's
architecture programmer's manual.
2014-03-03 14:44:57 +01:00
Andreas Sandberg
e7d230ede0 kvm: x86: Always assume segments to be usable
When transferring segment registers into kvm, we need to find the
value of the unusable bit. We used to assume that this could be
inferred from the selector since segments are generally unusable if
their selector is 0. This assumption breaks in some weird corner
cases.  Instead, we just assume that segments are always usable. This
is what qemu does so it should work.
2014-03-03 14:34:33 +01:00
Andreas Sandberg
739cc0128b kvm: Initialize signal handlers from startupThread()
Signal handlers in KVM are controlled per thread and should be
initialized from the thread that is going to execute the CPU. This
changeset moves the initialization call from startup() to
startupThread().
2014-03-03 14:31:39 +01:00
Nilay Vaish
5cd9dd29bd ruby: message buffer: changes related to tracking push/pop times
The last pop operation is now tracked as a Tick instead of in Cycles.
This helps in avoiding use of the receiver's clock during the enqueue
operation.
2014-03-01 23:59:58 -06:00
Nilay Vaish
67cd04b6fe ruby: make the max_size variable of the MessageBuffer unsigned 2014-03-01 23:59:57 -06:00
Christopher Torng
919baa603d cpu: Enable fast-forwarding for MIPS InOrderCPU and O3CPU
A copyRegs() function is added to MIPS utilities
to copy architectural state from the old CPU to
the new CPU during fast-forwarding. This
addition alone enables fast-forwarding for the
o3 cpu model running MIPS.

The patch also adds takeOverFrom() and
drainResume() functions to the InOrderCPU to
enable it to take over from another CPU. This
change enables fast-forwarding for the inorder
cpu model running MIPS, but not for Alpha.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2014-03-01 23:35:23 -06:00
Nilay Vaish
a533f3f983 ruby: profiler: statically allocate stats variable
Couple of users observed segmentation fault when the simulator tries to
register the statistical variable m_IncompleteTimes.  It seems that there
is some problem with the initialization of these variables when allocated
in the constructor.
2014-03-01 23:35:21 -06:00
Nilay Vaish
53f697a616 stats: updates due to c0db268f811b 2014-02-24 20:50:06 -06:00
Nilay Vaish
8504b079b8 ruby: correct errors in changeset 4eec7bdde5b0
Couple of errors were discovered in 4eec7bdde5b0 which necessitated this patch.
Firstly, we create interrupt controllers in the se mode, but no piobus was
being created.  RubyPort, which earlier used to ignore range changes now
forwards those to the piobus.  The lack of piobus resulted in segmentation
fault.  This patch creates a piobus even in se mode.  It is not created only
when some tester is running.  Secondly,  I had missed out on modifying port
connections for other coherence protocols.
2014-02-24 20:50:05 -06:00
Nilay Vaish
3b404fb1a0 stats: updates due to changes to ruby pio access handling 2014-02-23 19:16:16 -06:00
Nilay Vaish
7e27860ef4 ruby: route all packets through ruby port
Currently, the interrupt controller in x86 is connected to the io bus
directly.  Therefore the packets between the io devices and the interrupt
controller do not go through ruby.  This patch changes ruby port so that
these packets arrive at the ruby port first, which then routes them to their
destination.  Note that the patch does not make these packets go through the
ruby network.  That would happen in a subsequent patch.
2014-02-23 19:16:16 -06:00
Andreas Hansson
5755fff998 ruby: Simplify RubyPort flow control and routing
This patch simplfies the retry logic in the RubyPort, avoiding
redundant attributes, and enforcing more stringent checks on the
interactions with the normal ports. The patch also simplifies the
routing done by the RubyPort, using the port identifiers instead of a
heavy-weight sender state.

The patch also fixes a bug in the sending of responses from PIO
ports. Previously these responses bypassed the queue in the queued
port, and ignored the return value, potentially leading to response
packets being lost.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2014-02-23 19:16:16 -06:00
Nilay Vaish
6aafd5cb3f config: topologies: slight code refactor 2014-02-23 19:16:15 -06:00
Nilay Vaish
7572ab71b5 ruby: message buffer: refactor code
Code in two of the functions was exactly the same.  This patch moves
this code to a new function which is called from the two functions
mentioned initially.
2014-02-23 19:16:15 -06:00
Nilay Vaish
cde20fd476 ruby: remove few not required #includes 2014-02-23 19:16:15 -06:00
Nilay Vaish
82378f7301 ruby: slicc: remove unused COPY_HEAD functionality 2014-02-23 19:16:15 -06:00
Nilay Vaish
13ad07601b ruby: protocols: remove unused action z_stall 2014-02-23 19:16:15 -06:00
Nilay Vaish
385e542c5a config: ruby_random_test: updates due to recent unrelated changes 2014-02-21 08:02:06 -06:00
Nilay Vaish
cd33f9bc42 ruby: network: move message buffers to base network class. 2014-02-21 08:02:05 -06:00
Nilay Vaish
bd8f954526 ruby: network: garnet: fixed: removes net_ptr from links 2014-02-21 08:02:04 -06:00
Nilay Vaish
307f53e164 ruby: cache: remove not required variable m_cache_name 2014-02-21 08:02:02 -06:00
Nilay Vaish
f8f8b7e5c2 ruby: network: garnet: fixed: removes next cycle functions
At several places, there are functions that take a cycle value as input
and performs some computation.  Along with each such function, another
function was being defined that simply added one more cycle to input and
computed the same function.  This patch removes this second copy of the
function.  Places where these functions were being called have been updated
to use the original function with argument being current cycle + 1.
2014-02-20 17:28:01 -06:00
Nilay Vaish
896654746a ruby: controller: slight code refactoring 2014-02-20 17:27:45 -06:00
Nilay Vaish
0ce8c25919 ruby: mesi three level: rename incorrectly named files
Two files had been incorrectly named with a .cache suffix.

--HG--
rename : src/mem/protocol/MESI_Three_Level-L0.cache => src/mem/protocol/MESI_Three_Level-L0cache.sm
rename : src/mem/protocol/MESI_Three_Level-L1.cache => src/mem/protocol/MESI_Three_Level-L1cache.sm
2014-02-20 17:27:17 -06:00
Nilay Vaish
db5b3d37fe ruby: network: removes unused code. 2014-02-20 17:27:07 -06:00
Nilay Vaish
dd5c72e5a7 ruby: slicc: slight code refactoring 2014-02-20 17:26:49 -06:00
Nilay Vaish
b312a41f21 ruby: message buffer: removes some unecessary functions. 2014-02-20 17:26:41 -06:00
Andreas Sandberg
0d6009e8dc kvm: Add support for multi-system simulation
The introduction of parallel event queues added most of the support
needed to run multiple VMs (systems) within the same gem5
instance. This changeset fixes up signal delivery so that KVM's
control signals are delivered to the thread that executes the CPU's
event queue. Specifically:

  * Timers and counters are now initialized from a separate method
    (startupThread) that is scheduled as the first event in the
    thread-specific event queue. This ensures that they are
    initialized from the thread that is going to execute the CPUs
    event queue and enables signal delivery to the right thread when
    exiting from KVM.

  * The POSIX-timer-based KVM timer (used to force exits from KVM) has
    been updated to deliver signals to the thread that's executing KVM
    instead of the process (thread is undefined in that case). This
    assumes that the timer is instantiated from the thread that is
    going to execute the KVM vCPU.

  * Signal masking is now done using pthread_sigmask instead of
    sigprocmask. The behavior of the latter is undefined in threaded
    applications.

  * Since signal masks can be inherited, make sure to actively unmask
    the control signals when setting up the KVM signal mask.

There are currently no facilities to multiplex between multiple KVM
CPUs in the same event queue, we are therefore limited to
configurations where there is only one KVM CPU per event queue. In
practice, this means that multi-system configurations can be
simulated, but not multiple CPUs in a shared-memory configuration.
2014-02-20 15:43:53 +01:00
Andreas Hansson
fd9343eb85 arm: Bump stats after FS config script update
This patch updates the stats to reflect the change in kernel options
needed for armv8 (but used for all FS regressions).
2014-02-19 07:59:46 -05:00
Anthony Gutierrez
6b765ba8b7 arm: armv8 boot options to enable v8
Modifies FSConfig.py to enable ARMv8 compatibility.
To boot gem5 with ARMv8:
   Download the v8 kernel, .dtb file, and root FS from: http://gem5.org/Download
   Download the ARMv8 toolchain, and add the bin dir to your path:
       http://www.linaro.org/engineering/engineering-projects/armv8
   Build gem5 for ARM
   Build the v8 bootloader (in gem5/system/arm/aarch64_bootloader)
   Make script in gem5/system/arm/aarch64_bootloader will require v8 toolchain,
   drop the produced boot_emm.arm64 in $(M5_PATH)/binaries/
Run:
   $ build/ARM/gem5.fast configs/example/fs.py --machine-type=VExpress_EMM64 \
     --kernel=/path/to/kernel/vmlinux-linaro-tracking \
     --dtb-filename=/path/to/dtb/rtsm_ve-aemv8a.dtb \
     --disk-image=/path/to/img/linaro-minimal-armv8.img
2014-02-18 17:20:56 -05:00
Andreas Hansson
4b81585c49 mem: Fix bug in PhysicalMemory use of mmap and munmap
This patch fixes a bug in how physical memory used to be mapped and
unmapped. Previously we unmapped and re-mapped if restoring from a
checkpoint. However, we never checked that the new mapping was
actually the same, it was just magically working as the OS seems to
fairly reliably give us the same chunk back. This patch fixes this
issue by relying entirely on the mmap call in the constructor.
2014-02-18 05:51:01 -05:00
Andreas Hansson
f0ea79c41f dev: Include basic devices in NULL ISA build
This patch enbles use of the basic PIO devices as part of the NULL
build. Although it might seem counter intuitive to have a PIO device
without being able to execute a driver, this change enables us to
break a device class hierarchy into an ISA-agnostic part, and an
ISA-specific part, without requiring multiple-inheritance. The
ISA-agnostic base class is a PIO device, but does not make use of the
port.
2014-02-18 05:50:59 -05:00
Andreas Hansson
ffc838cd00 scons: Add PROTOC from the environment
This patch adds PROTOC to the build environment.
2014-02-18 05:50:58 -05:00
Andreas Hansson
969b436243 mem: Filter cache snoops based on address ranges
This patch adds a filter to the cache to drop snoop requests that are
not for a range covered by the cache. This fixes an issue observed
when multiple caches are placed in parallel, covering different
address ranges. Without this patch, all the caches will forward the
snoop upwards, when only one should do so.
2014-02-18 05:50:58 -05:00
Andreas Hansson
bf2f178f85 mem: Add a wrapped DRAMSim2 memory controller
This patch adds DRAMSim2 as a memory controller by wrapping the
external library and creating a sublass of AbstractMemory that bridges
between the semantics of gem5 and the DRAMSim2 interface.

The DRAMSim2 wrapper extracts the clock period from the config
file. There is no way of extracting this information from DRAMSim2
itself, so we simply read the same config file and get it from there.

To properly model the response queue, the wrapper keeps track of how
many transactions are in the actual controller, and how many are
stacking up waiting to be sent back as responses (in the wrapper). The
latter requires us to move away from the queued port and manage the
packets ourselves. This is due to DRAMSim2 not having any flow control
on the response path.

DRAMSim2 assumes that the transactions it is given are matching the
burst size of the choosen memory. The wrapper checks to ensure the
cache line size of the system matches the burst size of DRAMSim2 as
there are currently no provisions to split the system requests. In
theory we could allow a cache line size smaller than the burst size,
but that would lead to inefficient use of the DRAM, so for not we
fatal also in this case.
2014-02-18 05:50:53 -05:00
Andreas Hansson
e83fdc532b util: Enhance the error messages for packet encode/decode
This patch adds a more verbose error message when the Python protobuf
module cannot be loaded.
2014-02-18 05:50:52 -05:00
Andreas Hansson
c9cb492e1c mem: Fix input to DPRINTF in CommMonitor
Minor fix of the debug message parameters.
2014-02-18 05:50:51 -05:00
Nilay Vaish
5abbb84f02 stats: updates due to branch predictor warming 2014-02-16 11:40:34 -06:00
Nilay Vaish
0a44e16948 Added tag stable_2014_02_15 to the changeset 459491344fcf 2014-02-15 12:44:09 -06:00
Andreas Sandberg
c52190a695 cpu: simple: Add support for using branch predictors
This changesets adds branch predictor support to the
BaseSimpleCPU. The simple CPUs normally don't need a branch predictor,
however, there are at least two cases where it can be desirable:

  1) A simple CPU can be used to warm the branch predictor of an O3
     CPU before switching to the slower O3 model.

  2) The simple CPU can be used as a quick way of evaluating/debugging
     new branch predictors since it exposes branch predictor
     statistics.

Limitations:
  * Since the simple CPU doesn't speculate, only one instruction will
    be active in the branch predictor at a time (i.e., the branch
    predictor will never see speculative branches).

  * The outcome of a branch prediction does not affect the performance
    of the simple CPU.
2014-02-09 20:49:28 +01:00