Commit graph

661 commits

Author SHA1 Message Date
Nilay Vaish
c58bee829f sim: clocked object: function for converting cycles to ticks. 2015-08-11 11:39:23 -05:00
Andreas Sandberg
35d8e5b52b sim: Flag EventQueue::getCurTick() as const 2015-08-07 17:43:21 +01:00
Andreas Sandberg
f7ff27afe8 sim: Split ClockedObject to make it usable to non-SimObjects
Split ClockedObject into two classes: Clocked that provides the basic
clock functionality, and ClockedObject that inherits from Clocked and
SimObject to provide the functionality of the old ClockedObject.
2015-08-07 09:59:22 +01:00
Andreas Sandberg
53e777d683 base: Declare a type for context IDs
Context IDs used to be declared as ad hoc (usually as int). This
changeset introduces a typedef for ContextIDs and a constant for
invalid context IDs.
2015-08-07 09:59:13 +01:00
Andreas Sandberg
07815a3338 sim: Fixup comments and constness in draining infrastructure
Fix comments that got outdated by the draining rewrite. Also fixup
constness for methods in the querying drain state in the DrainManager.
2015-08-05 10:27:11 +01:00
Andreas Sandberg
7c904d9d3f sim: Initialize Drainable::_drainState to the system's state
It is sometimes desirable to be able to instantiate Drainable objects
when the simulator isn't in the Running state. Currently, we always
initialize Drainable objects to the Running state. However, this
confuses many of the sanity checks in the base class since objects
aren't expected to be in the Running state if the system is in the
Draining or Drained state.

Instead of always initializing the state variable in Drainable to
DrainState::Running, initialize it to the state the DrainManager is
in.

Note: This means an object can be created in the Draining/Drained
state without first calling drain().
2015-08-04 10:31:37 +01:00
Andreas Sandberg
feded87fc9 mem: Add probe support to the CommMonitor
This changeset adds a standardized probe point type to monitor packets
in the memory system and adds two probe points to the CommMonitor
class. These probe points enable monitoring of successfully delivered
requests and successfully delivered responses.

Memory system probe listeners should use the BaseMemProbe base class
to provide a unified configuration interface and reuse listener
registration code. Unlike the ProbeListenerObject class, the
BaseMemProbe allows objects to be wired to multiple ProbeManager
instances as long as they use the same probe point name.
2015-08-04 10:29:13 +01:00
Timothy Jones
c375870abd sim: function for testing for auto deletion
Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2015-08-03 23:08:40 -05:00
Timothy Jones
96091f358b uby: Fix checkpointing and restore
There are 2 problems with the existing checkpoint and restore code in ruby.
The first is that when the event queue is altered by ruby during serialization,
some events that are currently scheduled cannot be found (e.g. the event to
stop simulation that always lives on the queue), causing a panic.
The second is that ruby is sometimes serialized after the memory system,
meaning that the dirty data in its cache is flushed back to memory too late
and so isn't included in the checkpoint.

These are fixed by implementing memory writeback in ruby, using the same
technique of hijacking the event queue, but first descheduling all events that
are currently on it.  They are saved, along with their scheduled time, so that
the event queue can be faithfully reconstructed after writeback has finished.
Events with the AutoDelete flag set will delete themselves when they
are descheduled, causing an error when attempting to schedule them again.
This is fixed by simply not recording them when taking them off the queue.

Writeback is still implemented using flushing, so the cache recorder object,
that is created to generate the trace and manage flushing, is kept
around and used during serialization to write the trace to disk.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2015-08-03 23:08:40 -05:00
David Hashe
d0f6aad3c6 syscall: Add readlink to x86 with special case /proc/self/exe
This patch implements the correct behavior.
2015-07-20 09:15:18 -05:00
Nilay Vaish
aafa5c3f86 revert 5af8f40d8f2c 2015-07-28 01:58:04 -05:00
Nilay Vaish
608641e23c cpu: implements vector registers
This adds a vector register type.  The type is defined as a std::array of a
fixed number of uint64_ts.  The isa_parser.py has been modified to parse vector
register operands and generate the required code.  Different cpus have vector
register files now.
2015-07-26 10:21:20 -05:00
Brandon Potter
4f7c969e27 style: change Process function calls to use camelCase
The Process class methods were using an improper style and this subsequently
bled into the system call code.  The following regular expressions should be
helpful if someone transitions private system call patches on top of these
changesets:

s/alloc_fd/allocFD/
s/sim_fd(/simFD(/
s/sim_fd_obj/getFDEntry/
s/fix_file_offsets/fixFileOffsets/
s/find_file_offsets/findFileOffsets/
2015-07-24 12:25:23 -07:00
Brandon Potter
d5a7f09eb1 syscall_emul: standardized file descriptor name and add return checks.
The patch clarifies whether file descriptors are host file descriptors or
target file descriptors in the system call code.  (Host file descriptors
are file descriptors which have been allocated through real system calls
where target file descriptors are allocated from an array in the Process
class.)
2015-07-24 12:25:23 -07:00
Brandon Potter
b90711ea53 base: refactor process class (specifically FdMap and friends)
This patch extends the previous patch's alterations around fd_map.  It cleans
up some of the uglier code in the process file and replaces it with a more
concise C++11 version.  As part of the changes, the FdMap class is pulled out
of the Process class and receives its own file.
2015-07-24 12:25:22 -07:00
Brandon Potter
ef08046af4 syscall_emul: file descriptor interface changes
This patch gets rid of unused Process::dup_fd method and does minor
refactoring in the process class files.  The file descriptor max has been
changed to be the number of file descriptors since this clarifies the loop
boundary condition and cleans up the code a bit.  The fd_map field has been
altered to be dynamically allocated as opposed to being an array; the
intention here is to build on this is subsequent patches to allow processes
to share their file descriptors with the clone system call.
2015-07-24 12:25:22 -07:00
Andreas Sandberg
ed38e3432c sim: Refactor and simplify the drain API
The drain() call currently passes around a DrainManager pointer, which
is now completely pointless since there is only ever one global
DrainManager in the system. It also contains vestiges from the time
when SimObjects had to keep track of their child objects that needed
draining.

This changeset moves all of the DrainState handling to the Drainable
base class and changes the drain() and drainResume() calls to reflect
this. Particularly, the drain() call has been updated to take no
parameters (the DrainManager argument isn't needed) and return a
DrainState instead of an unsigned integer (there is no point returning
anything other than 0 or 1 any more). Drainable objects should return
either DrainState::Draining (equivalent to returning 1 in the old
system) if they need more time to drain or DrainState::Drained
(equivalent to returning 0 in the old system) if they are already in a
consistent state. Returning DrainState::Running is considered an
error.

Drain done signalling is now done through the signalDrainDone() method
in the Drainable class instead of using the DrainManager directly. The
new call checks if the state of the object is DrainState::Draining
before notifying the drain manager. This means that it is safe to call
signalDrainDone() without first checking if the simulator has
requested draining. The intention here is to reduce the code needed to
implement draining in simple objects.
2015-07-07 09:51:05 +01:00
Andreas Sandberg
f16c0a4a90 sim: Decouple draining from the SimObject hierarchy
Draining is currently done by traversing the SimObject graph and
calling drain()/drainResume() on the SimObjects. This is not ideal
when non-SimObjects (e.g., ports) need draining since this means that
SimObjects owning those objects need to be aware of this.

This changeset moves the responsibility for finding objects that need
draining from SimObjects and the Python-side of the simulator to the
DrainManager. The DrainManager now maintains a set of all objects that
need draining. To reduce the overhead in classes owning non-SimObjects
that need draining, objects inheriting from Drainable now
automatically register with the DrainManager. If such an object is
destroyed, it is automatically unregistered. This means that drain()
and drainResume() should never be called directly on a Drainable
object.

While implementing the new functionality, the DrainManager has now
been made thread safe. In practice, this means that it takes a lock
whenever it manipulates the set of Drainable objects since SimObjects
in different threads may create Drainable objects
dynamically. Similarly, the drain counter is now an atomic_uint, which
ensures that it is manipulated correctly when objects signal that they
are done draining.

A nice side effect of these changes is that it makes the drain state
changes stricter, which the simulation scripts can exploit to avoid
redundant drains.
2015-07-07 09:51:05 +01:00
Andreas Sandberg
d5f5fbb855 sim: Move mem(Writeback|Invalidate) to SimObject
The memWriteback() and memInvalidate() calls used to live in the
Serializable interface. In this series of patches, the Serializable
interface will be redesigned to make serialization independent of the
object graph and always work on the entire simulator. This means that
the Serialization interface won't be useful to perform maintenance of
the caches in a sub-graph of the entire SimObject graph. This
changeset moves these memory maintenance methods to the SimObject
interface instead.
2015-07-07 09:51:04 +01:00
Andreas Sandberg
e9c3d59aae sim: Make the drain state a global typed enum
The drain state enum is currently a part of the Drainable
interface. The same state machine will be used by the DrainManager to
identify the global state of the simulator. Make the drain state a
global typed enum to better cater for this usage scenario.
2015-07-07 09:51:04 +01:00
Andreas Sandberg
7773cb9565 sim: Add macros to serialize objects into a section
Add the SERIALIZE_OBJ / UNSERIALIZE_OBJ macros that serialize an
object into a subsection of the current checkpoint section.
2015-07-07 09:51:04 +01:00
Andreas Sandberg
b3ecfa6ae0 base: Add serialization support to Pixels and FrameBuffer
Serialize pixels as unsigned 32 bit integers by adding the required
to_number() and stream operators. This is used by the FrameBuffer,
which now implements the Serializable interface. Users of frame
buffers are expected to serialize it into its own section by calling
serializeSection().
2015-07-07 09:51:04 +01:00
Andreas Sandberg
888ec455cb sim: Fix broken event unserialization
Events expected to be unserialized using an event-specific
unserializeEvent call. This call was never actually used, which meant
the events relying on it never got unserialized (or scheduled after
unserialization).

Instead of relying on a custom call, we now use the normal
serialization code again. In order to schedule the event correctly,
the parrent object is expected to use the
EventQueue::checkpointReschedule() call. This happens automatically
for events that are serialized using the AutoSerialize mechanism.
2015-07-07 09:51:04 +01:00
Andreas Sandberg
76cd4393c0 sim: Refactor the serialization base class
Objects that are can be serialized are supposed to inherit from the
Serializable class. This class is meant to provide a unified API for
such objects. However, so far it has mainly been used by SimObjects
due to some fundamental design limitations. This changeset redesigns
to the serialization interface to make it more generic and hide the
underlying checkpoint storage. Specifically:

  * Add a set of APIs to serialize into a subsection of the current
    object. Previously, objects that needed this functionality would
    use ad-hoc solutions using nameOut() and section name
    generation. In the new world, an object that implements the
    interface has the methods serializeSection() and
    unserializeSection() that serialize into a named /subsection/ of
    the current object. Calling serialize() serializes an object into
    the current section.

  * Move the name() method from Serializable to SimObject as it is no
    longer needed for serialization. The fully qualified section name
    is generated by the main serialization code on the fly as objects
    serialize sub-objects.

  * Add a scoped ScopedCheckpointSection helper class. Some objects
    need to serialize data structures, that are not deriving from
    Serializable, into subsections. Previously, this was done using
    nameOut() and manual section name generation. To simplify this,
    this changeset introduces a ScopedCheckpointSection() helper
    class. When this class is instantiated, it adds a new /subsection/
    and subsequent serialization calls during the lifetime of this
    helper class happen inside this section (or a subsection in case
    of nested sections).

  * The serialize() call is now const which prevents accidental state
    manipulation during serialization. Objects that rely on modifying
    state can use the serializeOld() call instead. The default
    implementation simply calls serialize(). Note: The old-style calls
    need to be explicitly called using the
    serializeOld()/serializeSectionOld() style APIs. These are used by
    default when serializing SimObjects.

  * Both the input and output checkpoints now use their own named
    types. This hides underlying checkpoint implementation from
    objects that need checkpointing and makes it easier to change the
    underlying checkpoint storage code.
2015-07-07 09:51:03 +01:00
Andreas Sandberg
7cd5db8c6d sim: Add serialization macros for std containers 2015-07-07 09:51:03 +01:00
Curtis Dunham
31825bd988 sim, arm: add checkpoint upgrader for d02b45a5
The insertion of CONTEXTIDR_EL2 in the ARM miscellaneous registers
obsoletes old checkpoints.
2015-06-01 18:05:11 -05:00
Giacomo Gabrielli
cc2346e8ca arm: Implement some missing syscalls (SE mode)
Adding a few syscalls that were previously considered unimplemented.
2015-05-26 03:21:35 -04:00
Andreas Sandberg
db5c9a5f90 base: Redesign internal frame buffer handling
Currently, frame buffer handling in gem5 is quite ad hoc. In practice,
we pass around naked pointers to raw pixel data and expect consumers
to convert frame buffers using the (broken) VideoConverter.

This changeset completely redesigns the way we handle frame buffers
internally. In summary, it fixes several color conversion bugs, adds
support for more color formats (e.g., big endian), and makes the code
base easier to follow.

In the new world, gem5 always represents pixel data using the Pixel
struct when pixels need to be passed between different classes (e.g.,
a display controller and the VNC server). Producers of entire frames
(e.g., display controllers) should use the FrameBuffer class to
represent a frame.

Frame producers are expected to create one instance of the FrameBuffer
class in their constructors and register it with its consumers
once. Consumers are expected to check the dimensions of the frame
buffer when they consume it.

Conversion between the external representation and the internal
representation is supported for all common "true color" RGB formats of
up to 32-bit color depth. The external pixel representation is
expected to be between 1 and 4 bytes in either big endian or little
endian. Color channels are assumed to be contiguous ranges of bits
within each pixel word. The external pixel value is scaled to an 8-bit
internal representation using a floating multiplication to map it to
the entire 8-bit range.
2015-05-23 13:37:03 +01:00
Andreas Sandberg
37aab4a155 sim: Don't clear the active CPU vector in System::initState
The system class currently clears the vector of active CPUs in
initState(). CPUs are added to the list by registerThreadContext()
which is called from BaseCPU::init(). This obviously breaks when the
System object is initialized after the CPUs. This changeset removes
the offending clear() call since the list will be empty after it has
been instantiated anyway.
2015-05-15 13:39:44 -04:00
Steve Reinhardt
c65fa3dceb syscall_emul: fix warn_once behavior
The current ignoreWarnOnceFunc doesn't really work as expected,
since it will only generate one warning total, for whichever
"warn-once" syscall is invoked first.  This patch fixes that
behavior by keeping a "warned" flag in the SyscallDesc object,
allowing suitably flagged syscalls to warn exactly once per
syscall.
2015-05-05 09:25:59 -07:00
Ruslan Bukin
81f3211149 arch, base, dev, kern, sym: FreeBSD support
This adds support for FreeBSD/aarch64 FS and SE mode (basic set of syscalls only)

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2015-04-29 22:35:23 -05:00
Brandon Potter
4991c29965 syscall_emul: implement clock_gettime system call 2015-04-22 07:51:27 -07:00
Brandon Potter
344a437064 syscall_emul: update getrlimit to use warn
Don't use std::cerr directly, and just return EINVAL instead of aborting.
2015-04-22 07:51:27 -07:00
Brandon Potter
9c6509f198 syscall_emul: fix warning with wrong syscall name
Also nix extra whitespace.
2015-04-22 07:51:27 -07:00
Nilay Vaish
d6af46915c sim: Use NULL instead of None for testing filenames.
The filenames are initialized with NULL.  So the test should be
checking for them to be == NULL instead == None.
2015-04-13 17:33:57 -05:00
Nilay Vaish
b26fef8466 sim: fix function for emulating dup()
The function was using the host fd to obtain the fd object from the simulated
process.
2015-04-13 17:33:57 -05:00
Ruslan Bukin
bebab7f24f sim: correct check for endianess
Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2015-04-03 11:42:10 -05:00
Curtis Dunham
a1164154de sim: Update limit_event reuse to final version
Matching final version on reviewboard.
2015-03-26 11:16:44 -04:00
Curtis Dunham
564482c782 sim: Reuse the same limit_event in simulate()
This patch accomplishes two things:
1. Makes simulate()'s GlobalSimLoopExitEvent a singleton reused
   across calls. This is slightly more efficient than recreating
   it every time.
2. Gives callers to simulate() (especially other simulators) a
   foolproof way of knowing that the simulation period ended
   successfully by hitting the limit event. They can call
   getLimitEvent() and compare it to the return
   value of simulate().

This change was motivated by an ongoing effort to integrate gem5
and SST, with SST as the master sim and gem5 as the slave sim.
2015-03-23 06:57:36 -04:00
Andreas Hansson
f26a289295 mem: Split port retry for all different packet classes
This patch fixes a long-standing isue with the port flow
control. Before this patch the retry mechanism was shared between all
different packet classes. As a result, a snoop response could get
stuck behind a request waiting for a retry, even if the send/recv
functions were split. This caused message-dependent deadlocks in
stress-test scenarios.

The patch splits the retry into one per packet (message) class. Thus,
sendTimingReq has a corresponding recvReqRetry, sendTimingResp has
recvRespRetry etc. Most of the changes to the code involve simply
clarifying what type of request a specific object was accepting.

The biggest change in functionality is in the cache downstream packet
queue, facing the memory. This queue was shared by requests and snoop
responses, and it is now split into two queues, each with their own
flow control, but the same physical MasterPort. These changes fixes
the previously seen deadlocks.
2015-03-02 04:00:35 -05:00
Andreas Hansson
e17328a227 mem: mmap the backing store with MAP_NORESERVE
This patch ensures we can run simulations with very large simulated
memories (at least 64 TB based on some quick runs on a Linux
workstation). In essence this allows us to efficiently deal with
sparse address maps without having to implement a redirection layer in
the backing store.

This opens up for run-time errors if we eventually exhausts the hosts
memory and swap space, but this should hopefully never happen.
2015-02-16 03:33:47 -05:00
Andreas Sandberg
550c318490 sim: Move the BaseTLB to src/arch/generic/
The TLB-related code is generally architecture dependent and should
live in the arch directory to signify that.

--HG--
rename : src/sim/BaseTLB.py => src/arch/generic/BaseTLB.py
rename : src/sim/tlb.cc => src/arch/generic/tlb.cc
rename : src/sim/tlb.hh => src/arch/generic/tlb.hh
2015-02-11 10:23:27 -05:00
Andreas Sandberg
fe200c2487 sim: Remove test for non-NULL this in Event
The method Event::initialized() tests if this != NULL as a part of the
expression that tests if an event is initialized. The only case when
this check could be false is if the method is called on a null
pointer, which is illegal and leads to undefined behavior (such as
eating your pets) according to the C++ standard. Because of this,
modern compilers (specifically, recent versions of clang) warn about
this which we treat as an error. This changeset removes the redundant
check to fix said warning.
2015-02-03 14:25:48 -05:00
Curtis Dunham
b89fd57663 sim: prioritize async events; prevent starvation
If a time quantum event is the only one in the queue, async
events (Ctrl-C, I/O, etc.) will never be processed.

So process them first.
2014-12-19 15:32:34 -06:00
Ali Saidi
9d8ddd92dc sim: Clean up InstRecord
Track memory size and flags as well as add some comments and consts.
2015-01-25 07:22:44 -05:00
Ali Saidi
f6742ea26e cpu: Remove all notion that we know when the cpu is misspeculating.
We have no way of knowing if a CPU model is on the wrong path with
our execute-in-execute CPU models. Don't pretend that we do.
2015-01-25 07:22:26 -05:00
mike upton
cb911559dc arm: Add unlinkat syscall implementation
added ARM aarch64 unlinkat syscall support, modeled on other <xxx>at syscalls.
This gets all of the cpu2006 int workloads passing in SE mode on aarch64.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2015-01-03 17:51:48 -06:00
Joel Hestness
642b9b4fab syscall_emul: Return correct writev value
According to Linux man pages, if writev is successful, it returns the total
number of bytes written. Otherwise, it returns an error code. Instead of
returning 0, return the result from the actual call to writev in the system
call.
2014-12-27 13:48:40 -06:00
Andreas Hansson
d66b14ca61 misc: Another round of static analysis fixups
Mostly addressing uninitialised members.
2014-11-24 09:03:38 -05:00
Alexandru Dutu
1f539f13c3 mem: Page Table map api modification
This patch adds uncacheable/cacheable and read-only/read-write attributes to
the map method of PageTableBase. It also modifies the constructor of TlbEntry
structs for all architectures to consider the new attributes.
2014-11-23 18:01:09 -08:00