python: Don't try to bind a stat group to the NULL simobject.

That is a SimObject like object which is used when a SimObject
parameter is purposefully left empty, vs. being accidentally left
empty through a typo or accidental ommission.

It doesn't have a getCCObject method, and attempting to use it anyway
causes gem5 to crash.

Change-Id: Ie86321fbdbcc41cf88b7009184423acd7b64484b
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21059
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

stats: Ignore non-Group objects in stat hierarchy

Some objects, such as SystemC modules, are not a subclass of
Stat::Group. Calling the addStatGroup function on them causes errors.
This changes ignores those objects that are not Stat::Group in the stat
hierarchy.

Signed-off-by: Chun-Chen TK Hsu <chunchenhsu@google.com>
Change-Id: I9b62419417b7af7331461fbfaf15e45a4ee2b35f
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20680
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

python: Make the dot writer handle unconnected Port vector elements.

Change-Id: I5234013716cdcce5fc39e239dc3d92cd1f2b7799
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20699
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>

stats: Add support for listing available formats

Add a command line option to list available stat formats and their
documentation.

Change-Id: I7f5f2272d9b0176639f59f2efedb9cab2f7da5b9
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19670
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

stats: Add beta support for HDF5 stat dumps

This changeset add support for stat dumps in the HDF5 file
format. HDF5 is a binary data format that represents data in a
file-system-like balanced tree. It has native support for
N-dimensional arrays and binary data (e.g., frame buffers).

It has the following benefits over traditional text stat files:

* Efficient storage of time series (multiple stat dumps)

* Fast lookup of stats

* Plenty of existing tooling (e.g., Python libraries and graphical
viewers)

* File format can be used to store frame buffers together with
normal stats.

Drawbacks:

* Large startup cost (single stat dump larger than text equivalent)

* Stat dumps are slower than text

Known limitations:

* Distributions and histograms aren't supported.

HDF5 stat output can be enabled using the 'h5' URL scheme when
overriding the stat file name on gem5's command line. The following
parameters are supported:

* chunking (unsigned): Number of time steps to pre-allocate
(default: 10)

* desc (bool): Output stat descriptions (default: True)

* formulas (bool): Output derived stats (default: True)

Example gem5 command line:

./build/ARM/gem5.opt \
--stats-file="h5://stats.h5?desc=False;formulas=False" \
configs/example/fs.py

Example Python stat consumer that computes IPC:
import h5py

f = h5py.File('stats.h5', 'r')
group = f['/system/cpu']
for i, c in zip(group['committedInsts'], group['numCycles']):
print i, c, i / c

Change-Id: I351c6cbff2fb7bef9012f47876ba227ed288975b
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/8121
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Reviewed-by: Ciro Santilli <ciro.santilli@arm.com>

stats: Add support for partial stat dumps

Add support for partial stat dumps by passing an optional 'root'
keyword argument to m5.stats.dump(). Specifying root slightly changes
the semantics of the dump command. For legacy reasons, gem5 only
allows one stat dump per tick. This is likely a limitation introduced
as a hack to prevent automatic dumping at the end of simulation from
interfering with explicit dumping from a simulation script. This
restriction does not apply when specifying a root. However, these stat
dumps will still prevent an additional stat dump in the same tick with
an unspecified root.

N.B.: This new API /only/ works for new-style stats that have an
explicit hierarchy. Legacy stats will not be dumped if a root is
specified.

Change-Id: Idc8ff448b9f70a796427b4a5231e7371485130b4
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19369
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

stats: Add support for hierarchical stats

This change makes the stat system aware of the hierarchical nature of
stats. The aim is to achieve the following goals:

* Make the SimObject hierarchy explicit in the stat system (i.e.,
get rid of name() + ".foo"). This makes stat naming less fragile
and makes it possible to implement hierarchical formats like
XML/HDF5/JSON in a clean way.

* Make it more convenient to split stats into a separate
struct/class that can be bound to a SimObject. This makes the
namespace cleaner and makes stat accesses a bit more obvious.

* Make it possible to build groups of stats in C++ that can be used
in subcomponents in a SimObject (similar to what we do for
checkpoint sections). This makes it easier to structure large
components.

* Enable partial stat dumps. Some of our internal users have been
asking for this since a full stat dump can be large.

* Enable better stat access from Python.

This changeset implements solves the first three points by introducing
a class (Stats::Group) that owns statistics belonging to the same
object. SimObjects inherit from Stats::Group since they typically have
statistics.

New-style statistics need to be associated with a parent group at
instantiation time. Instantiation typically sets the name and the
description, other parameters need to be set by overriding
Group::regStats() just like with legacy stats. Simple objects with
scalar stats can typically avoid implementing regStats() altogether
since the stat name and description are both specified in the
constructor.

For convenience reasons, statistics groups can be merged into other
groups. This means that a SimObject can create a stat struct that
inherits from Stats::Group and merge it into the parent group
(SimObject). This can make the code cleaner since statistics tracking
gets grouped into a single object.

Stat visitors have a new API to expose the group structure. The
Output::beginGroup(name) method is called at the beginning of a group
and the Output::endGroup() method is called when all stats, and
sub-groups, have been visited. Flat formats (e.g., the text format)
typically need to maintain a stack to track the full path to a stat.

Legacy, flat, statistics are still supported after applying this
change. These stats don't belong to any group and stat visitors will
not see a Output::beginGroup(name) call before their corresponding
Output::visit() methods are called.

Change-Id: I9025d61dfadeabcc8ecf30813ab2060def455648
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19368
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>

python: FdtState using interrupt-cells

Change-Id: I37813748f518b442d2b53c2bc4f381edb2e26146
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20050
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

python: Add support for exporting static class methods from c++

This change adds support for exporting static methods in a c++
SimObject from the coressponsing python wrapper class. This will allow
us to define and use c++ methods without the need to instantiate an
object of the corresponding class.

Change-Id: Iaf24c1aa6f20feb5c91241f46ec8db005a6a0c0c
Signed-off-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Signed-off-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19168
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

misc: dot_writer fixup

In large configs the tooltip may be greater then the maximum line
size graphviz supports when parsing the dot file (typically 16k).
Adding '/' causes graphviz to break the string in multiple lines
while parsing and works around this limitation.

Change-Id: I16a0030127de4165080de97f5213309eed9fdeca
Signed-off-by: Tiago Mück <tiago.muck@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19208
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

python: Fix AddrRange legacy ParamValue wrapper

This change fixes a bug that would manifest if a user would
instantiate an AddrRange ParamValue using the kwargs 'intlvBits' and
'intlvHighBit' without specifying the optional 'xorHighBit'.

Change-Id: I2091c432234df9cf907d52af6ba7f0cadd8c37a8
Signed-off-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19248
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

python: Fix cxx_ini_parse for ScopedEnum

Change-Id: I69534bbbc16b2d24a65fa1dee4926f213c3618ef
Signed-off-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19152
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

python: Add binding for the new AddrRange c++ constructor

Change-Id: I5b3fb59a11d8587a753759310dd3b2748ac13a0b
Signed-off-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19132
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

base: Extend AddrRange to support more flexible addressing

Previously an AddrRange could express interleaving using a number of
consecutive bits and in additional optionally a second number of
consecutive bits. The two sets of consecutive bits would be xored and
matched against a value to determine if an address is in the
AddrRange. For example:

sel[0] = a[8] ^ a[12]
sel[1] = a[9] ^ a[13]
where sel == intlvMatch

This change extends AddrRange to allow more flexible interleavings
with an abritary number of set of bits which do not need be
consecutive. For example:

sel[0] = a[8] ^ a[11] ^ a[13]
sel[1] = a[15] ^ a[17] ^ a[19]
where sel == intlvMatch

Change-Id: I42220a6d5011a31f0560535762a25bfc823c3ebb
Signed-off-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19130
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>

misc: Added dot_writer for Ruby's network topology

Change-Id: Ic71ca7bc2eb4174d70afa368bc9cc987f3df89e9
Signed-off-by: Tiago Muck <tiago.muck@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17548
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

mem: Minimize the use of MemObject.

MemObject doesn't provide anything beyond its base ClockedObject any
more, so this change removes it from most inheritance hierarchies.
Occasionally MemObject is replaced with SimObject when I was fairly
confident that the extra functionality of ClockedObject wasn't needed.

Change-Id: Ic014ab61e56402e62548e8c831eb16e26523fdce
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18289
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>

python: Get rid of the VectorPort constructor.

The only thing it was doing beyond calling the parent Port __init__ was
to set isVec, and nobody actually looks at that value later.

Change-Id: I567cb583e6f02a6c18504b9bb20dd13b3c934822
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18175
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

python: Replace the Master/Slave Ports with Request/Response ports.

These are a little more descriptive and a little less potentially
offensive.

Change-Id: I84c30f783f0a4c242cb4f54ab272b6fdf1e9eec7
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18174
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

python: Generalize the Port.splice function.

Now that the MASTER and SLAVE roles aren't special, the splice function
needs to be able to handle arbitrarily role-d peers.

Change-Id: I22a28b7cdcb93f7f370730b7e38b0e6d3500a6a0
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18170
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

python: Generalize the dot_writer to handle non Master/Slave roles.

Change-Id: I6d93c28e754c0cacacdd5e8885c45bc861135e94
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18169
Maintainer: Gabe Black <gabeblack@google.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

python: Make Port roles a more generic concept.

A recent change got rid of the strict Master => Slave port relationship
which used to be checked in python and instead left the checking up to
C++. One major downside to this approach is that it was no longer
obvious in the configuration what was supposed to be connected to what,
and it still left the arbitrary and misleading MasterPort and SlavePort
types in the Ethernet devices which could now connect with each other
symmetrically but couldn't actually connect to an arbitrary
MasterPort/SlavePort.

This change exposes the base Port and VectorPort types, and makes them
accept a "role" parameter in __init__ which used to be set directly by
their subclasses. This role can be any string, and will be used later
to check for compatiblity and to give a hint as to what can be
connected to what in the SimObject definitions.

To make the checks work with arbitrary compatible pairs, the base Port
type now has a class method called compat() which accepts a pair of
roles which will become mutually compatible, ie any port with the first
role will be allowed to connect to any port with the second role, and
vice versa. To be self compatible, the same role should be passed in
for both parameters.

To maintain compatibility, the MasterPort and SlavePort types are
retained, but now they're nothing special and could have been set up
in any arbitrary SimObject .py file. The same is true for
MasterVectorPort and SlaveVectorPort.

Also, since we can no longer assume that all edges in the dot graph of
the config should start with a port with the MASTER role and end with
a port with the SLAVE role, Ports now track an is_source property which
says whether the arrow head should be surpressed at that end of the
edge representing the connection.

Change-Id: Ifcc6faab05e437ad87cd21f0ba613b09cf21c321
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18168
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Gabe Black <gabeblack@google.com>

python: fix tracing after Python 3 refactor

gem5.opt --debug-flags ExecAll

was failing with:

ImportError: No module named defines

on Python 2.

Change-Id: I06959d6e0ccb7c661c7c749af3392632dac779f3
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18108
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

base,python: Fix to allow multiple --debug-ignore values.

When adding multiple SimObjects to --debug-ignore, either separating the values with
a colon or adding multiple --debug-ignore flags, the previous code only ignored the
last SimObject in the list. This changeset adds and uses new `ObjectMatch::add` and
`Logger::addIgnore` methods to make the functionality of the flag consistent with
its description.

Change-Id: Ib6967a48611ea59a211f81af2a970c4de429b1be
Signed-off-by: Isaac Sánchez Barrera <isaac.sanchez@bsc.es>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17488
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

arch, cpu, dev, gpu, mem, sim, python: start using getPort.

Replace the getMasterPort, getSlavePort, and getEthPort functions
with getPort, and remove extraneous mechanisms that are no longer
necessary.

Change-Id: Iab7e3c02d2f3a0cf33e7e824e18c28646b5bc318
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17040
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

python: Switch to the new getPort mechanism to connect ports.

This retrieves ports using the getPort method, and connects them using
the bind method on the ports themselves. Any smarts as far as what type
of peers are allowed to connect or how they connect is left up to the
individual bind methods.

Change-Id: Ic640d1fce8af1bed411116e5830edc4a8a0f9d66
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17039
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

sim: Add a getPort function to SimObject.

This will retrieve a Port object from a given SimObject (which might
not be a MemObject) no matter what flavor of Port it is.

Change-Id: I636b85e9d4929a05a769e165849106bcb5f3e9c1
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17037
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

python: Change || to && for MessageBuffers in connectPorts.

The connectPorts function currently checks if *either* of the peers in
a port connection are a MessageBuffer, and if so will ignore the
connection. This CL changes that || into a && so that *both* of the
peers need to be a Ruby types (either a MessageBuffer or Network) for
the connection to be ignored. That makes it easier to contain that
abnormal behavior to those types instead of having it apply even when
other types of port owners are involved.

Unfortunately the number of interesting Ruby types is unbounded, but
these are the types with ports as of today. This mechanism will
hopefully be replacedall together so this should be a temporary issue.

Change-Id: I140498770e5d37eb2abd3d99261d47e111f1c8ab
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17031
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

python: Improve how templated SimObject classes are handled.

When setting up a SimObject's Param structure, gem5 will autogenerate
a header file which attempts to declare the SimObject's C++ type. It
has had at least some level of sophistication there where it would
pull off the namespaces ahead of the class name and handle them
properly, but it didn't know how to handle templates.

This change improves that handling in two ways. First, it adds a new
magical SimObject attribute called 'cxx_template_params' which is used
to specify what the template parameters are as a list. For instance, if
your SimObject was a template which took an integer constant as its
first parameter and a type as its second, this attribute could look
like the following:

cxx_template_params = [ 'int FOO', 'class Bar' ]

Importantly, if there are any default values for these template
parameters, they should *not* be included here, they should be
specified where the class is later defined.

The second new mechanism is to add an internal CxxClass in the
SimObject.cxx_param_decl method. This class accepts the class signature
in the cxx_class attribute and the cxx_template_params and does two
things. First, it strips off namespaces like in the old implementation.
Second, it extracts and processes any template arguments attached to
the class. If these are constants (as determined by the contents of
cxx_template_params), then they are stored verbatim. If they're types,
then they're recursively expanded into a CxxClass and stored that way.
Note that these are the *values* of the template arguments, where as
cxx_template_params lists the *types* and *names* of those arguments.
In our earlier example, if cxx_class was:

cxx_class = 'CoolClasses::ClassName<12, Fruit::Apple>'

Then CxxClass would extract the namespace 'CoolClasses', the class
name 'ClassName', the argument '12', and the argument 'Fruit::Apple'.
That second argument would be expanded into a CxxClass with the
namespace 'Fruit' and the class name 'Apple'.

Importantly here, because there were no default arguments given in
cxx_template_params, all "hidden" arguments which would fall through
to their defaults need to be fully specified in cxx_class.

The CxxClass has a method called declare() which uses the information
extracted earlier to output all of the "stuff" necessary for declaring
the given class, including opening any containing namespaces and
putting template<...> ahead of the actual class declaration with the
template parameters specified.

If any of the template arguments are themselves CxxClass instances,
then they'll be recursively declared immediately before the current
class is.

An alternative solution to this problem might be to include the header
file which actually defines the cxx_class type to avoid having to
come up with a declaration. Unfortunately this doesn't work since it
can set up include loops where the SimObject C++ header file includes
the param header to get access to the Param type, but that includes
the C++ header to get access to the SimObject type.

This also makes it harder for SimObjects to refer to each other, since
they rely on the declaration in the params header files when declaring
a member pointer to that type in their own Param structures.

Change-Id: I68cfc36ddff6d789eb4cdef5178c4619ac2cc8b1
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17228
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>

python: Simplify connectPorts() around EtherObject/EtherDevice.

EtherDevice now inherits EtherObject and shares the same getEthPort
virtual function, so there's no need to treat them separately any more.

Change-Id: Ia6c147fd97fece4a281c296521a7b095f793d32e
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17030
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

python: Teach cxxMethod how to set return_value_policy.

This is passed through to the underlying call to PyBindMethod.

Change-Id: Ib46c55664ba0707464bb84e137a0fad817aea1bb
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17034
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

python: Teach PyBindMethod how to set return_value_policy.

Change-Id: Ia208e43672672556b36f905e8f71dce44b978d22
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17033
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

python: Fix unknown params and proxy multiplication

One of the recent changes made params not visible anymore:
NameError: global name 'params' is not defined
This is fixed by adding the proper import statement.

However, the second error makes the multiplication values be assigned
to other proxies (that are not even used on the multiplication). A
workaround is added to prevent this from happening by extending "*=".

Change-Id: I3ad276a456efff62058672d16caac2b3ad1b326b
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17048
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

python: Fix issue when Self proxy resolves to a another proxy

The problem occurs when a proxy is being resolved to another proxy
that hasn't been resolved yet. The problematic case that was
triggering this issues in the VGIC. It was caused by parameters
looking a bit like this:

gic = Param.GicV2(Parent.any)
some_param = Param.Int(Self.gic.some_param)

When 'some_param' was resolved, it found the 'gic' parameter in
Self. However, that parameter hadn't been resolved yet, so the
existing code was setting the proxy evaluation context to the
unresolved Parent.any proxy without first unproxying it.

It seems like this bug depends on the graph traversal order and I have
so far only seen it when compiling gem5 with Python 3.

Change-Id: Iea12cc138765e70bfd6bb776b1efa012364db066
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/16004
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

scons: Marshal Python sources using the same Python as gem5

We currently use the Python version used by scons to marshal Python
code. This doesn't work when building gem5 with Python 3 support since
scons typically runs in Python 2.7. Add a custom marshal helper that
links with the same library as gem5 to generate byte code that is
guaranteed to work in gem5's Python interpreter.

Change-Id: I665b0f2078726d4c055d74a3e668a580fc613b59
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/16422
Reviewed-by: Gabe Black <gabeblack@google.com>

systemc: Add m5.systemc and m5.tlm python modules.

These will be how systemc and tlm APIs which are not attached to
SimObjects will be exposed. This avoids having to artificially attach
them to wrapping SimObjects for instance, which is a bit awkward
and non-obvious.

The python code which attaches the systemc and tlm modules to the
m5 modules lives in src/python/m5/__init__.py, but the modules
themselves live in src/systemc/python to keep all the systemc code
grouped together. It might be a little confusing to have a small part
of the glue that adds those modules in a separate place (__init__.py),
but that is, as far as I can tell, unavoidable, and it's better in my
opinion to keep the systemc code grouped together than to put it
alongside the other python code and __init__.py.

Change-Id: Iecb218daec5e15772152b5ad22b51f43b86c3d4b
Reviewed-on: https://gem5-review.googlesource.com/c/16563
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Gabe Black <gabeblack@google.com>

python: Stop using basestring to test for strings

The base class basestring doesn't exist in Python 3. Use string_types
from six instead.

Change-Id: I7e84903fb7dd4a0af7ae4e9f4ec2e54338f212bb
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15998
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Juha Jäykkä <juha.jaykka@arm.com>

python: Add Python 3 workarounds for long

Python 3 doesn't have a separate long type. Make long an alias for int
where needed to maintain compatibility.

Change-Id: I4c0861302bc3a2fa5226b3041803ef975d29b2fd
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15988
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>

python: Fix params/proxy import loop

There is a circular dependency between params and proxy at import
time. This causes issues for Python 3. Add the imports to the specific
methods with the dependencies to make the import happen when the
method is executed instead.

Change-Id: I770112fd3c07c395459e204976942bda3dc7236f
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15993
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Juha Jäykkä <juha.jaykka@arm.com>

python: Enforce absolute imports for Python 3 compatibility

Change-Id: Ia88d7fd472f7aed9b97df81468211384981bf6c6
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15983
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

python: Add fallbacks for packages that have been renamed

Python 3 has restructured some packages. Specifically, __builtin__ has
been renamed to builtins and urlparse has been included in urllib.

Change-Id: I81f8f3942471db1043006a36abbad6e5a49e0a43
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15994
Reviewed-by: Juha Jäykkä <juha.jaykka@arm.com>

python: Fix param -> int conversion issues

Python 3 doesn't convert params to integers automatically in
range(). Add __index__ to CheckedInt to enable implicit conversions
again. Add explicit conversions where necessary.

Change-Id: I2de6c9906d3bb7616f12ada6728b9e4b1928511c
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/16000
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

python: Make iterator handling Python 3 compatible

Many functions that used to return lists (e.g., dict.items()) now
return iterators and their iterator counterparts (e.g.,
dict.iteritems()) have been removed. Switch calls to the Python 2.7
iterator methods to use the Python 3 equivalent and add explicit list
conversions where necessary.

Change-Id: I0c18114955af8f4932d81fb689a0adb939dafaba
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15992
Reviewed-by: Juha Jäykkä <juha.jaykka@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

python: Add missing operators to NumericParamValue

Add missing operators to NumericParamValue and ensure that they are
able to work on the underlying value if the right hand side is a
param.

Change-Id: I2bd86662aee9891bbd89aed7ebe20b827b5528bd
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/16001
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>

python: Fix Param initialization issue in Python 3

When initializing a param with a SimObject NULL pointer, convert()
checks if the 'ptype' attribute has been created and whether the value
is NULL. In that case, it assumes that the object is being
initizalized as a part of SimObject initialization and defers the
conversion. This check is implemented using hasattr() which in turn is
implemented using the __getattr__ implementation that asserts because
all SimObjects haven't been initialized yet.

Implement the check using a lookup in the object's dictionary instead
to prevent the SimObject lookup.

Change-Id: I7367563c4fb71f6d2be541ebdc0be418e9f73d48
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15990
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>

python: Use __name__ instead of func_name for Py3 compat

Change-Id: I62a9685b4bce7e9012bc65309fcafe26135fde6d
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15997
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>

python: Add __bool__ helpers in addition to __nonzero__

Python 3 uses __bool__ instead of __nonzero__ when performing a
Boolean comparison.

Change-Id: I85185bbe136ecae67346fa23569e24edd7329222
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15996
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>

config: Make parameter conversion handle integers in other bases.

Python's float() function/type can't handle hexadecimal notation, but
int() can. Since there are also cases where converting to a float and
then back to an int (or long) can cause rounding error, this change
splits toFloat and toInteger apart and makes them call a worker
function which accepts a conversion function which does the work of
converting a numeric string into an actual number.

in the case of toFloat, it still uses the standard float(), and in the
case of toInteger it uses a lambda which wraps int(x, 0).

Change-Id: Ic46cf4ae86b7eba6f55d731d1b25e3f84b8bb64c
Reviewed-on: https://gem5-review.googlesource.com/c/16504
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

python: Remove uses of tuple unpacking in function params

Python 3 doesn't support tuple unpacking in function parameters and
lambdas.

Change-Id: I36c72962e33a9ad37145089687834becccc76adb
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15991
Reviewed-by: Gabe Black <gabeblack@google.com>

python: Replace deprecated repr syntax

Change-Id: I5f9538cf2ca5ee17c51e7c5388d3aef363fcfa54
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15989
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>

python: Switch from using compare to key in list sort

Python 3 has deprecated the use of a comparison function in favour of
a key extraction function.

Change-Id: I4b7eab791ecbdfbf7147f57fdbc7cbe8f1de20dd
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15995
Reviewed-by: Gabe Black <gabeblack@google.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>

python: Replace dict.has_key with 'key in dict'

Python 3 has removed dict.has_key in favour of 'key in dict'.

Change-Id: I9852a5f57d672bea815308eb647a0ce45624fad5
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15987
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>

python: Add missing defines import

The _check_tracing helper function in main.py depends on defines to
check if tracing has been enabled at compile time. This module is
imported in main() but not at the module level, which breaks this
function.

Change-Id: I26d65a4320da8618e0e552553695884fd2c880e0
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/16402
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>

python: Replace DictMixin with Mapping / MutableMapping

Python 3 has removed support for DictMixin, so switch to Mapping /
MutableMapping in collections which provides the same functionality.

Change-Id: I61fbe366d2c9fc6e01b470f82f49cc02b99dec32
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15984
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

python: Replace orderdict with collections.OrderedDict

Python 2.7 and newer has support for ordered dictionaries in the
standard library. Remove this custom class.

Change-Id: I4b720405aa3c4ce8d5c0b401eefe744a85ac3a3e
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/16362
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

python: Update use of exec to work with Python 3

Python 3 uses 'exec(code, globals)' instead of 'exec code in
globals'. Switch to the newer syntax since it is supported by Python
2.7. Also, move check_tracing out of main to work around a bug in
Python 2.7.

Change-Id: I6d390160f58783e1b038a572b64cdf3ff09535fa
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15986
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

python: Switch to using open instead of file

Python 3 doesn't support the file(name, mode) syntax which has been
deprecated in favour of open.

Change-Id: I35ef8690d97a5243860a64ff985fd22fa86253f1
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15985
Reviewed-by: Gabe Black <gabeblack@google.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>

python: Make exception handling Python 3 safe

Change-Id: I9c2cdfad20deb1ddfa224320cf93f2105d126652
Reviewed-on: https://gem5-review.googlesource.com/c/15980
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>

python: Remove getCode() type workaround

Python 2.7 requires a workaround when wrapping exit objects to
explicitly convert the return of getCode() to int to not confuse
sys.exit. This workaround isn't needed and doesn't work on Python 3
since it doesn't have a separate long integer type.

Change-Id: I57bc3fd8f4699676c046ece8a52baa2796959ffd
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15978
Reviewed-by: Gabe Black <gabeblack@google.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>

python: Always throw TypeError on slave-slave connections

params.py checks the validity of memory port-port connections before
they are instantiated in C++. This commit ensures that attempting to
connect two slave ports together will cause a TypeError.

Change-Id: Ia7d0a15df28b96c7bf5e568c4f4917d21a19b824
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15896
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

python: Add support for scoped enums

At the moment gem5 has support for enum params that either generate a
unscoped within the Enums namespace or a struct encapsulated enum. The
Enums namespace is getting quite big and some params have the same
names which results in collisions. This change adds support for the
scoped enums.

Change-Id: I930e1cc3b814081627b653939e75d6c43956a334
Signed-off-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15395
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

config: De-nest the code in Port.splice().

The error checking in that function used an if/else structure where
one of the two branches would be the error condition which would cause
the function to exit. Because the function would exit if an error was
detected, there's no reason to have the non-error condition guarded in
the other half of the if.

This change de-nests the non-error cases to make the function simpler
and easier to read.

Change-Id: Idedf54e84a178fa5a2a47f96373374152e420cf3
Reviewed-on: https://gem5-review.googlesource.com/c/15516
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

config: Fix an error message in Port.splice().

That error message referenced non-existent variables which were likely
renamed without updating the error message.

Change-Id: I6878802ef4b83e3fdf75a860d848b8c5e2e8d6c0
Reviewed-on: https://gem5-review.googlesource.com/c/15515
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

sim: Fix data type of ticks per second before passing it to C++

Casts ticks per second value to int before passing it to C++. Python
throws an error because of incompatible type because of the recent
change.

Change-Id: Ibcaf8c327f1be0dba38763975d389584addd8373
Reviewed-on: https://gem5-review.googlesource.com/c/14375
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

sim: Push the global frequency management code into C++.

That makes it available when python is left out, and makes it available
to c++ code without having to call back into python.

Change-Id: If82e7e8eff526f2b957f84afe046e1d56fed4aa2
Reviewed-on: https://gem5-review.googlesource.com/c/14055
Reviewed-by: Srikant Bharadwaj <srikant.bharadwaj@amd.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

python: Add utility function to override config parameters

Add a utility method, SimObject.apply_config that can be used to
implement SimObject param overrides from the command line. This
function provides safe and convenient semantics for CLI assignment:

* The override expression is evaluated in a restricted environment. The
only global variables are the child objects and params from the root
object.

* Only params can be overridden. For example, calling methods or setting
attributes on SimObjects isn't possible.

* Vectors use non-standard list semantics which enable something similar
to glob expansion on the shell. For example, setting:

root.system.cpu[0:2].numThreads = 2

will override numThreads for cpu 0 and 1 and:

root.system.cpus[0,2].numThreads = 2

sets it for cpus 0 and 2.

The intention is that the helper method is called to override default
values before calling m5.instantiate.

Change-Id: I73f99da21d6d8ce1ff2ec8db2bb34338456f6799
Reviewed-on: https://gem5-review.googlesource.com/c/12984
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

python: Stop conditionally excluding code from pyobject.cc

Now that the Ether* classes are included in all builds, there's no
reason to conditionally compile code in pyobject.cc.

Change-Id: If94602af71774b1f090a3344a633207f4b37d308
Reviewed-on: https://gem5-review.googlesource.com/c/13470
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

python: Fix call bug in @cxxMethod when override is True

Change-Id: Ifa9efbd329fd01eb13100bc6690e651df2c12294
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Javier Setoain <javier.setoain@arm.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/11514
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

python: Fixup incorrect syntax in PyBind argument handler

Change-Id: Ie81104d89b554795ec1020d5ce4edcf28795eda8
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/11511
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

python: Add support for multiplying proxies to compatible Param

Previously we allowed multiplications between proxy Param and
compatible constants (int, long, float). This change extends this
functionality and adds support for multiplying with between proxy
Param and compatible proxy Param.

Change-Id: I23a083881ae4d770e818895b893534767cd2472d
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/11510
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

sim: Use the canonical way of iterating over a dictionary

Instead of using a convoluted getattr call, use the conventional
iteritems() interface.

Change-Id: I6d6bbccf865f8a0e8ff0767914157a7460099b09
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/10782
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

sim: Add a SimObject python field which overrides the default c++ base.

The base for the c++ version of python SimObject classes is normally
inferred from the c++ version of the python base. There are some
specific cases where that isn't desired. This change makes it possible
to override the default behavior.

Change-Id: I2438dad767e2f56823bad42b3e6c7714ce97ef79
Reviewed-on: https://gem5-review.googlesource.com/10662
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

sim: Rename the SimObject cxx_bases field to cxx_extra_bases.

cxx_bases adds in additional c++ base classes beyond those implied by
the python SimObject inheritance hierarchy. To imply the fact that
these are additional bases, and to disambiguate a future mechanism
which changes the implied bases, this flag/field is being renamed from
cxx_bases to cxx_extra_bases.

As far as I can tell, this field was only used internally in
SimObject.py.

Change-Id: Ie7cc3d0107ff71cc31424d6e20c9a2f430022ab9
Reviewed-on: https://gem5-review.googlesource.com/10661
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

scons: Switch from the print statement to the print function.

Starting with version 3, scons imposes using the print function instead
of the print statement in code it processes. To get things building
again, this change moves all python code within gem5 to use the
function version. Another change by another author separately made this
same change to the site_tools and site_init.py files.

Change-Id: I2de7dc3b1be756baad6f60574c47c8b7e80ea3b0
Reviewed-on: https://gem5-review.googlesource.com/8761
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>

arm: DT autogeneration - Device Tree generation methods

This patch adds an extra layer to the pyfdt library such that usage
gets easier and device tree nodes can be specified in less code,
without limiting original usage. Note to not import both the pyfdt
and fdthelper in the same namespace (but generally fdthelper is all
you need, because it supplies the same classes even when they are not
extended in any way)

Also, this patch lays out the primary functionality for generating a
device tree, where every SimObject gets an empty generateDeviceTree
method and ArmSystems loop over their children in an effort to merge
all the nodes. Devices are implemented in other patches.

Change-Id: I4d0a0666827287fe42e18447f19acab4dc80cc49
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5962
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

ext: DT autogeneration - Add PyFtd to m5 space

This patch adds pyfdt.py to the m5.ext module. This is used in
succeeding patches for generating and editing dtb files and flat
device trees for DT autogeneration.

The file is in the m5_root/src/python/m5/ext directory, as opposed to
the m5_root/ext, because this library is part of the m5 object space
and linking to the m5_root/ext directory from the SConscript file
in src/python can not be done reliably. Linking from the root level
SConscript is also not an option, because it doesn't have the PySource
method defined.

Cloned from: https://github.com/superna9999/pyfdt
Commit: accbcd254584c9295a18878d32999d0c7c156f8e
Version: 0.3

Change-Id: I928bdc912a9507d1f8a3290acf445c7cae496552
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5961
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

misc: Rename misc.(hh|cc) to logging.(hh|cc)

These files aren't a collection of miscellaneous stuff, they're the
definition of the Logger interface, and a few utility macros for
calling into that interface (panic, warn, etc.).

Change-Id: I84267ac3f45896a83c0ef027f8f19c5e9a5667d1
Reviewed-on: https://gem5-review.googlesource.com/6226
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>

scons: Switch from "guards" to "tags" on source files.

Tags are just arbitrary strings which are attached to source files
which mark them as having some property. By default, all source files
have the "gem5 lib" tag added to them which marks them as part of the
gem5 library, the primary component of the gem5 binary but also a
seperable component for use in, for example, system C.

The tags can be completely overridden by setting the "tags" parameter
on Source, etc., functions, and can be augmented by setting "add_tags"
which are tags that will be added, or alternatively additional tags.
It's possible to specify both, in which case the tags will be set to
the union of tags and add_tags. add_tags is supposed to be a way to
add extra tags to the default without actually overriding the default.
Both tags and add_tags can be a list/tuple/etc of tags, or a single
string which will be converted into a set internally.

Other existing tags include:
1. "python" for files that need or are used with python and are
excluded when the --without-python option is set
2. "main" for the file(s) which implement the gem5 binary's main
function.
3. The name of a unit test to group its files together.
4. Tags which group source files for partial linking.

By grouping the "tags" into a single parameter instead of taking all
extra parameters as tags, the extra parameters can, in the future, be
passed to the underlying scons environment. Also, the tags are either
present or not. With guards, they could be present and True, present
and False, or not present at all.

Change-Id: I6d0404211a393968df66f7eddfe019897b6573a2
Reviewed-on: https://gem5-review.googlesource.com/5822
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

config: Add an Energy param type.

This type expects values in joules (J).

Change-Id: I77a3a4f1c19443f573d5fe7a84d5abd954ce1603
Reviewed-on: https://gem5-review.googlesource.com/5625
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

config: Export the "Current" param type from m5.params.

This type was defined, but it was never added to __all__.

Change-Id: I5414829a9562790416f5ceab71af01503d142903
Reviewed-on: https://gem5-review.googlesource.com/5624
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

util: Add a "toEnergy" function to the convert module.

Change-Id: I7299af0e2a6ce9bd2272d6ccb898997336e95e51
Reviewed-on: https://gem5-review.googlesource.com/5623
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

config: Simplify the definitions of the Voltage and Current params.

These had a lot of code which duplicated what was already in the
Float param value class. Also, printing into the ini file with "%f"
forces python to truncate values which require more precision than the
fixed float format supports.

Change-Id: Iad9623b71a31d17b69c184082585dcbb881eaa20
Reviewed-on: https://gem5-review.googlesource.com/5622
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

util: Simplify/consolidate the python conversion module.

The python conversion module was really repetitive and fragmented,
where some types of conversions use common code, and some use hand
written case statements which did something very similar. Also, some
types like Voltage could only handle V and mV but no other scaling
prefix.

This change restructures the module to centralize a lot of the unit
handling code into toFloat, and makes the various other functions use
it.

Change-Id: Ic8529203cc226c9b551b8535a444e3f2f25ad1eb
Reviewed-on: https://gem5-review.googlesource.com/5621
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

util: Make dot_writer ignore NULL simobjects.

Also centralize the code which iterates over the parameters of a simnode's
children, and remove a copy/paste block of code in the DVFS block of code.

Change-Id: I01305fbff59346010780ee386ba97ad9106b1f5d
Reviewed-on: https://gem5-review.googlesource.com/4849
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>

sim: Add a get_config_as_dict to the NullSimObject class.

Change-Id: I1ba6f6b196b7dfa790d1baaa23640bb3ed73f450
Reviewed-on: https://gem5-review.googlesource.com/4847
Maintainer: Gabe Black <gabeblack@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

sim: Don't add the NULL SimObject as a child of other SimObjects.

Change-Id: Ibdc48af8e5a461077f75d781cfd8191586c54115
Reviewed-on: https://gem5-review.googlesource.com/4846
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>

sim: Give the NullSimObject singleton a _name.

The name is 'Null', and is what __str__ returns.

Change-Id: I113f52496f5e9133b8d03206289b719fda003582
Reviewed-on: https://gem5-review.googlesource.com/4845
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>

sim: Add a NullSimObject.descendants function.

Null simobjects don't have any descendants.

Change-Id: Ia43a99056709f422c9c817c017912d23d689fb1e
Reviewed-on: https://gem5-review.googlesource.com/4844
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>

sim: Add a clear_parent function to NullSimObject.

Change-Id: I3842176f147997105fcc62aaf9cb93b9896708be
Reviewed-on: https://gem5-review.googlesource.com/4843
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>

sim: Check the SimObjectVector.has_parent function to use the "any" function.

The existing code was essentially doing the same thing, but in a more
roundabout and obscure way. One difference between the two versions is that
I believe this will stop as soon as it encounters an element without a
parent, where the original version would call has_parent() on all the
elements regardless.

Change-Id: Ia1fef3083fc88fca11f8ecfca453476e33194695
Reviewed-on: https://gem5-review.googlesource.com/4842
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>

sim: Only consider non-NULL elements in SimObjectVector.has_parent.

NullSimObject doesn't have a has_parent function, and it's not clear what its
return value should be if one were added. The appropriate value seems to
depend on why some other bit of code is checking if there's a parent in the
first place.

In SimObjectVector, the has_parent function is checking whether all of its
elements have a parent. In this particular case, the most reasonable thing
to do seems to be to just skip those elements.

Change-Id: I5f8cad66d1b22c5e37962492fd77cff9371e5af8
Reviewed-on: https://gem5-review.googlesource.com/4841
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>

sim: Add a set_parent to NullSimObject which does nothing.

This lets attempts to set_parent on NullSimObject fall away harmlessly
without having to add a bunch of checks whenever set_parent is called.

Change-Id: I6d3510772ba71e765c4739e486e9f3d2460c4e11
Reviewed-on: https://gem5-review.googlesource.com/4840
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>

python: Make GlobalExitEvent.getCode() return an int

PyBind normally casts integers returned from the C to long in
Python. This is normally fine since long in most cases behaves just
like an int. However, when passing the return value from getcode() to
sys.exit, unexpected behavior ensues. Due to the way the function is
defined, any type other than int (with the exception of None) will be
treated as an error and be equivalent to sys.exit(1).

Since we frequently use the sys.exit(event.getCode()) pattern, we need
to ensure that the function returns an integer. This change adds an
explicit type conversion to a Python integer in the wrapper code.

Change-Id: I73d6b881025064afa2b2e6eb4512fa2a4b0a87da
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jose Marinho <jose.marinho@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/4280
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Joe Gross <joe.gross@amd.com>

python: Fix unproxing of VectorParams

Previously proxy vector parameters would resolve correctly only for
Parent.all. Any other proxy such as Parent.any, or exact ones such as
Parent.addr_range would resolve to a *vector* of the right value
resulting into a vector of a vector. For example if we set:

DirectoryController0.addr_range = [0x100000-0x1fffff, 0x200000-0x2fffff]
DirectoryMemory0.addr_range = Parent.addr_range

where DirectoryController0 is the parent SimObject of DirectoryMemory0
after unproxying the Parent.addr_range VectorParam we would get

DirectoryMemory0.addr_range = [[0x100000-0x1fffff, 0x200000-0x2fffff]]

This change unifies handling of all three proxies to the same correct
unproxy mechanism.

Change-Id: Ie5107f69f58eb700b3e1b92c55210e0d53e6788d
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2901
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

python: Fix PyEvent reference counting bug

The current implementation of reference counting for PyEvents only
partially works. The native object is currently kept alive while it is
in the event queue. However, if the Python object goes out of scope,
the Python side of this object is garbage collected which leaves a
"dangling" native object. This results in confusing error messages
where PyBind is unable to find the Python implementation of an event
when it is triggered.

Implement reference counting using the generalized reference counting
API instead.

Change-Id: I4e8e04abc4f61dff238d718065f5371e73b38ab3
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/3222
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

python: Prevent Python wrappers from deleting SimObjects

The PyBind wrappers could potentially delete SimObjects if they don't
have any references. This is not desirable since there could be
pointers to such objects within the C++ world. This problem doesn't
normally occur since Python typically holds a pointer to the root node
as long as the simulator is running.

Prevent SimObject and Param deletion by using a PyBind-prescribed
unique_ptr with a dummy deleter as the pointer wrapper for the Python
world.

Change-Id: Ied14602c9ee69a083a69c5dae1b5fcf8efb4548a
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/3224
Reviewed-by: Gabe Black <gabeblack@google.com>

python: Fix weird memory issue in wrapped AddrRange vectors

There is a weird issue with the PyBind wrapper of
vector<AddrRange>. Assigning new values to a param that is a vector of
AddrRange sometimes results in an out-of-bounds memory access.

We work around this issue by treating AddrRange vectors as opaque
types. This slightly changes the semantics of the wrapper since Python
now manipulates the real object rather than a copy that has been
converted to a list.

Change-Id: Ie027c06e7a7262214b43b19a76b24fe4b20426c5
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Sascha Bischoff <sascha.bischoff@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-by: Timothy Hayes <timothy.hayes@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/3223
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

python: Remove unused readline import

The readline module is imported by main.py but doesn't seem to be
used.

Change-Id: I7888e3b6ad0a0fedc14b0feec2adf0a39883bbf8
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/3421
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

python: Add a helper function to create Python events

Add a helper function, m5.event.create(), to create events from
Python. This function takes a callable Python object (e.g., a
function) as an argument and optionally a priority as a keyword
argument. This function was accidentally dropped from the public API
when switching to PyBind.

Change-Id: Icbd0e392d9506934ec2c9f541199aa35c1c2df8c
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/3220
Reviewed-by: Gabe Black <gabeblack@google.com>

style: fix line lengths and include ordering

The style checker complains about line length and ordering for these
files. This fix should make these two files kosher.

Change-Id: I822a0518a98d9e379a543d2017e90c4e9666a58d
Reviewed-on: https://gem5-review.googlesource.com/3380
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

misc: Add the --listener-loopback-only command line option.

This option invokes the Listener::loopbackOnly() static function which
will make the port listeners bind to the loopback device exclusively and
ignore connections on other devices. That prevents external agents like
port scanners from disrupting simulations with spurious connections.

Change-Id: I46b22165046792a6f970826c109bdbce7db25c84
Reviewed-on: https://gem5-review.googlesource.com/3082
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

misc: Expose the listener loopbackOnly function to python.

Change-Id: Ibb405af54a46a93706a6f476b5314491e84be0c8
Reviewed-on: https://gem5-review.googlesource.com/3081
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

python: Fix debug flag listing regression

The PyBind11 changes slightly modified gem5's internal debug
interfaces. The corresponding change to the public API went missing
before the new bindings were merged. This change updates the Python
glue to use the new interface.

Change-Id: I3ecca5a3f6c35b99d55126d697371124f81a12dd
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Matteo Andreozzi <matteo.andreozzi@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/3140
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

python: Remove SWIG

Remove SWIG-specific Python code.

Change-Id: If1d1b253d84021c9a8f9a64027ea7a94f2336dff
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Andreas Hansson <andreas.hansson@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2922
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Tony Gutierrez <anthony.gutierrez@amd.com>

python: Use PyBind11 instead of SWIG for Python wrappers

Use the PyBind11 wrapping infrastructure instead of SWIG to generate
wrappers for functionality that needs to be exported to Python. This
has several benefits:

* PyBind11 can be redistributed with gem5, which means that we have
full control of the version used. This avoid a large number of
hard-to-debug SWIG issues we have seen in the past.

* PyBind11 doesn't rely on a custom C++ parser, instead it relies on
wrappers being explicitly declared in C++. The leads to slightly
more boiler-plate code in manually created wrappers, but doesn't
doesn't increase the overall code size. A big benefit is that this
avoids strange compilation errors when SWIG doesn't understand
modern language features.

* Unlike SWIG, there is no risk that the wrapper code incorporates
incorrect type casts (this has happened on numerous occasions in
the past) since these will result in compile-time errors.

As a part of this change, the mechanism to define exported methods has
been redesigned slightly. New methods can be exported either by
declaring them in the SimObject declaration and decorating them with
the cxxMethod decorator or by adding an instance of
PyBindMethod/PyBindProperty to the cxx_exports class variable. The
decorator has the added benefit of making it possible to add a
docstring and naming the method's parameters.

The new wrappers have the following known issues:

* Global events can't be memory managed correctly. This was the
case in SWIG as well.

Change-Id: I88c5a95b6cf6c32fa9e1ad31dfc08b2e8199a763
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Andreas Hansson <andreas.hansson@arm.com>
Reviewed-by: Andrew Bardsley <andrew.bardsley@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2231
Reviewed-by: Tony Gutierrez <anthony.gutierrez@amd.com>
Reviewed-by: Pierre-Yves Péneau <pierre-yves.peneau@lirmm.fr>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

python: Automatically disable listeners in batch setups

Determine if gem5 is running in a batch environment by checking if
STDIN is wired to a TTY or not. If the simulator is running in a batch
environment, disable all listeners by default. This behavior can be
overridden using the --enable-listeners option.

Change-Id: I404c709135339144216bf08a2769c016c543333c
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Sean McGoogan <sean.mcgoogan@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2322
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

base: Refactor logging to make log level selection cleaner

It's currently possible to change the log level in gem5 by tweaking a
set of global variables. These variables are currently exposed to
Python using SWIG. This mechanism is far from ideal for two reasons:
First, changing the log level requires that the Python world enables
or disables individual levels. Ideally, this should be a single call
where a log level is selected. Second, exporting global variables is
poorly supported by most Python frameworks. SWIG puts variables in
their own namespace and PyBind doesn't seem to support it at all.

This changeset refactors the logging code to create a more abstract
interface. Each log level is associated with an instance of a Logger
class. This class contains common functionality, an enable flag, and a
verbose flag.

Available LogLevels are described by the LogLevel class. Lower log
levels are used for more critical messages (PANIC being level 0) and
higher levels for less critical messages. The highest log level that
is printed is controlled by calling Logger:setLevel().

Change-Id: I31e44299d242d953197a8e62679250c91d6ef776
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Gabor Dozsa <gabor.dozsa@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

python: Add a generalized mechanism to configure stats

Add a mechanism to configure the stat output format using a URL-like
syntax. This makes it possible to specify both an output format
(currently, only text is supported) and override default
parameters.

On the Python-side, this is implemented using a helper function
(m5.stats.addStatVisitor) that adds a visitor to the list of active
stat visitors. The helper function parses a URL-like stat
specification to determine the stat output type. Optional parameters
can be specified to change how stat visitors behave.

For example, to output stats in text format without stat descriptions:

m5.stats.addStatVisitor("text://stats.txt?desc=False")

From the command line:

gem5.opt --stats-file="text://stats.txt?desc=False"

Internally, the stat framework uses the _url_factory decorator
to wrap a Python function with the fn(path, **kwargs) signature in a
function that takes a parsed URL as its only argument. The path and
keyword arguments are automatically derived from the URL in the
wrapper function.

New output formats can be registered in the m5.stats.factories
dictionary. This dictionary contains a mapping between format names
(URL schemes) and factory methods.

To retain backwards compatibility, the code automatically assumes that
the user wants text output if no format has been specified (i.e., when
specifying a plain path).

Change-Id: Ic4dce93ab4ead07ffdf71e55a22ba0ae5a143061
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-by: Sascha Bischoff <sascha.bischoff@arm.com>
Reviewed-by: Ilias Vougioukas <ilias.vougioukas@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Tony Gutierrez <anthony.gutierrez@amd.com>

misc: Add Python.h header to pyevents.hh

Signed-off-by: Jason Lowe-Power <jason@lowepower.com>

style: Force Python.h to be included before main header

Python's header files set various compiler macros (e.g.,
_XOPEN_SOURCE) unconditionally. This triggers preprocessor warnings
that end up being treated as errors. The Python integration manual [1]
strongly recommends that Python.h is included before any system
header. The style guide used to mandate that Python.h is included
first in any file that needs it. This requirement was changed to
always include a source file's main header first, which ended up
triggering these errors.

This change updates the style checker to always include Python.h
before the main header file.

[1] https://docs.python.org/2/extending/extending.html

Change-Id: Id6a4f7fc64a336a8fd26691a0ca682abeb1d1579
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Pierre-Yves Péneau <pierre-yves.peneau@lirmm.fr>

python: Move native wrappers to the _m5 namespace

Swig wrappers for native objects currently share the _m5.internal name
space with Python code. This is undesirable if we ever want to switch
from Swig to some other framework for native binding (e.g., PyBind11
or Boost::Python). This changeset moves all of such wrappers to the
_m5 namespace, which is now reserved for native code.

Change-Id: I2d2bc12dbc05b57b7c5a75f072e08124413d77f3
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

style: [patch 3/22] reduce include dependencies in some headers

Used cppclean to help identify useless includes and removed them. This
involved erroneously included headers, but also cases where forward
declarations could have been used rather than a full include.

style: [patch 1/22] use /r/3648/ to reorganize includes

python: Don't use Swig to cast stats

Call the stat visitor from the stat itself rather than casting stats
in Python. This reduces the number of ways visitors are called.

Change-Id: Ic4d0b7b32e3ab9897b9a34cd22d353f4da62d738
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Sascha Bischoff <sascha.bischoff@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Joe Gross <joseph.gross@amd.com>

sim: Remove redundant export_method_cxx_predecls

The headers declared in export_method_cxx_predecls are redundant since a
SimObject's main header is automatically included.

Change-Id: Ied9e84630b36960e54efe91d16f8c66fba7e0da0
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-by: Joe Gross <joseph.gross@amd.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

python: Export periodicStatDump

Some configuration scripts need periodic stat dumps. One of the ways
this can be achieved is by using the pariodicStatDump helper
function. This function was previously only exported in the internal
name space. Export it as a normal function in m5.stat instead.

Change-Id: Ic88bf1fd33042a62ab436d5944d8ed778264ac98
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Sascha Bischoff <sascha.bischoff@arm.com>

base: eliminate ipython warning

Change-Id: I3e282baeb969b6bb9534813a2f433d68246c0669
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>

misc: Remove FullSystem check for networking components
Ethernet devices are currently only hooked up if running in FS mode. Much of
the Ethernet networking code is generic and can be used to build non-Ethernet
device models. Some of these device models do not require a complex driver
stack and can be built to use an EmulatedDriver in SE mode. This patch enables
etherent interfaces to properly connect regardless of whether the simulation
is in FS or SE mode.

base: Output all AddrRange parameters to config.ini

Currently only 'start' and 'end' of AddrRange are printed in config.ini.
This causes address ranges to be overlapping when loading a c++-only
config with interleaved addresses using CxxConfigManger. This patch adds
prints for the interleave and XOR bits to config.ini such that address
ranges are properly setup with cxx config.

power: Allow voltage to be configured via cmd line

---
src/python/m5/params.py | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

misc: Bail out of DVFS dot if we cannot resolve the domains

This changeset updates the dot output to bail out if it is unable to
resolve the voltage or clock domains (which will cause it to raise an
AttributeError). Additionally, the DVFS dot output is disabled by
default for speed purposes.

Minor fixup for 0aeca8f.

misc: Add secondary dot output for DVFS domains

This patch adds a secondary dot output file which shows the DVFS domains. This
has been done separately for now to avoid cluttering the already existing
diagram. Due to the way that the clock domains are assigned to components in
gem5, this output must be generated after the C++ objects have been
instantiated. This further motivates the need to generate this file separately
to the current dot output, and not to replace it entirely.

misc: Don't build region.py as a PySource

The style refactor change (style: Refactor the style checker as a
Python package) moved region.py from src/python/m5/util/ to
util/style/. The SConscript update accidentally got lost in that
commit. This commit removes region.py from src/python/SConscript.

Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>

style: Refactor the style checker as a Python package

Refactor the style checker into a Python module that can be reused by
command line tools that integrate with git. In particular:

* Create a style package in util
* Move style validators from style.py to the style/validators.py.
* Move style verifiers from style.py to the style/verifiers.py.
* Move utility functions (sort_includes, region handling,
file_types) into the style package
* Move generic code from style.py to style/style.py.

Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-by: Steve Reinhardt <steve.reinhardt@amd.com>

sim: Add support for forking

This changeset adds forking capabilities to the gem5 python scripts. A fork
method is added to simulate.py. This method is responsible for forking the
simulator itself, and will direct all output files to a new output directory
based on the fork sequence number. The default name of the output directory is
the same as the parent with the suffix ".fN" added where N is the fork sequence
number. The fork method provides the option to specify if the system should be
drained prior to forking, or not. By default the system is drained to ensure
that there are no in-flight transactions.

When forking the simulator, the fork method returns the PID of the child
process, or returns 0 if running in the child. This is in line with the standard
Python forking interface.

Signed-off-by: Andreas Sandberg <andreas@sandberg.pp.se>
[sascha.bischoff@arm.com: Rebased patches onto a newer gem5 version]
Signed-off-by: Sascha Bischoff <sascha.bischoff@arm.com>
[andreas.sandberg@arm.com: Updated to comply with modern draining semantics ]
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>

sim: Add support for notifying Drainable objects of a fork

When forking a gem5 process, some objects need to clean up resources
(mainly file descriptions) shared between the child and the parent of
the fork. This changeset adds the notifyFork() method to Drainable,
which is called in the child process.

Signed-off-by: Andreas Sandberg <andreas@sandberg.pp.se>
[sascha.bischoff@arm.com: Rebased patches onto a newer gem5 version]
Signed-off-by: Sascha Bischoff <sascha.bischoff@arm.com>
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>

base: Add support for changing output directories

This changeset adds support for changing the simulator output
directory. This can be useful when the simulation goes through several
stages (e.g., a warming phase, a simulation phase, and a verification
phase) since it allows the output from each stage to be located in a
different directory. Relocation is done by calling core.setOutputDir()
from Python or simout.setOutputDirectory() from C++.

This change affects several parts of the design of the gem5's output
subsystem. First, files returned by an OutputDirectory instance (e.g.,
simout) are of the type OutputStream instead of a std::ostream. This
allows us to do some more book keeping and control re-opening of files
when the output directory is changed. Second, new subdirectories are
OutputDirectory instances, which should be used to create files in
that sub-directory.

Signed-off-by: Andreas Sandberg <andreas@sandberg.pp.se>
[sascha.bischoff@arm.com: Rebased patches onto a newer gem5 version]
Signed-off-by: Sascha Bischoff <sascha.bischoff@arm.com>
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>

configs: add command-line option to stop debug output

This patch adds a --debug-end flag to main.py so that debug output can be
stoped at a specified tick, while allowing the simulation to continue. It is
useful in situations where you would like to produce a trace for a region of
interest while still collecting stats for the entire run. This is in contrast
to the currently existing --debug-break flag, which terminates the simulation
at the tick.

style: fix missing spaces in control statements

Result of running 'hg m5style --skip-all --fix-control -a'.

style: remove trailing whitespace

Result of running 'hg m5style --skip-all --fix-white -a'.

sim: fix redundant --debug-start help string

Just changes the metavar for --debug-start from TIME
to TICK in cset 72046b9b3323 and didn't notice that the
comment "must be in ticks" is now redundant.

sim: don't ignore SIG_TRAP

By ignoring SIG_TRAP, using --debug-break <N> when not connected to
a debugger becomes a no-op. Apparently this was intended to be a
feature, though the rationale is not clear.

If we don't ignore SIG_TRAP, then using --debug-break <N> when not
connected to a debugger causes the simulation process to terminate
at tick N. This is occasionally useful, e.g., if you just want to
collect a trace for a specific window of execution then you can combine
this with --debug-start to do exactly that.

In addition to not ignoring the signal, this patch also updates
the --debug-break help message and deletes a handful of unprotected
calls to Debug::breakpoint() that relied on the prior behavior.

dev: Move network devices to src/dev/net/

config: Fix broken SimObject listing

The gem5 option '--list-sim-objects' is supposed to list all available
SimObjects and their parameters. It currently chokes on SimObjects
with parameters that have an object instance as their default
value. This is caused by __str__ in SimObject trying to resolve its
complete path. When the path resolution method reaches the parent
object (a MetaSimObject since it hasn't been instantiated), it dies
with a Python exception.

This changeset adds a guard to stop path resolution if the parent
object is a MetaSimObject.

config: Added missing types to JSON/INI Python reader

Added the missing types EthernetAddr and Current to the JSON/INI file
reader example configs/example/read_config.py.

Also added __str__ to EthernetAddr to make values appear in the same form
in JSON an INI files.

sim: print pid in output header

This information is useful if you have a bunch of simulations running
and want to know which one to kill, but you've neglected to take
advantage of the previous patch and embed the pid in your output path.

base: remove Trace::enabled flag

The DTRACE() macro tests both Trace::enabled and the specific flag. This
change uses the same administrative interface for enabling/disabling
tracing, but masks the SimpleFlags settings directly. This eliminates a
load for every DTRACE() test, e.g. DPRINTF.

ruby: Expose MessageBuffers as SimObjects

Expose MessageBuffers from SLICC controllers as SimObjects that can be
manipulated in Python. This patch has numerous benefits:
1) First and foremost, it exposes MessageBuffers as SimObjects that can be
manipulated in Python code. This allows parameters to be set and checked in
Python code to avoid obfuscating parameters within protocol files. Further, now
as SimObjects, MessageBuffer parameters are printed to config output files as a
way to track parameters across simulations (e.g. buffer sizes)

2) Cleans up special-case code for responseFromMemory buffers, and aligns their
instantiation and use with mandatoryQueue buffers. These two special buffers
are the only MessageBuffers that are exposed to components outside of SLICC
controllers, and they're both slave ends of these buffers. They should be
exposed outside of SLICC in the same way, and this patch does it.

3) Distinguishes buffer-specific parameters from buffer-to-network parameters.
Specifically, buffer size, randomization, ordering, recycle latency, and ports
are all specific to a MessageBuffer, while the virtual network ID and type are
intrinsics of how the buffer is connected to network ports. The former are
specified in the Python object, while the latter are specified in the
controller *.sm files. Unlike buffer-specific parameters, which may need to
change depending on the simulated system structure, buffer-to-network
parameters can be specified statically for most or all different simulated
systems.

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.

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.

python: Remove redundant drain when changing memory modes

When the Python helper code switches CPU models, it sometimes also
needs to change the memory mode of the simulator. When this happens,
it accidentally tried to drain the simulator despite having done so
already. This changeset removes the redundant drain.

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.

misc: quote args in echoed command line

Currently if there are shell special characters in a
command-line argument, you can't copy and paste the
echoed command line onto a shell prompt because the
characters aren't quoted properly. This patch fixes
that problem.

base: Add XOR-based hashed address interleaving

This patch extends the current address interleaving with basic hashing
support. Instead of directly comparing a number of address bits with a
matching value, it is now possible to use two independent set of
address bits XOR'ed together. This avoids issues where strided address
patterns are heavily biased to a subset of the interleaved ranges.

config: Fix typo in Float param

The Float param was not settable on the command line
due to a typo in the class definition in
python/m5/params.py. This corrects the typo and allows
floats to be set on the command line as intended.

sim: fix reference counting of PythonEvent

When gem5 is a slave to another simulator and the Python is only used
to initialize the configuration (and not perform actual simulation), a
"debug start" (--debug-start) event will get freed during or immediately
after the initial Python frame's execution rather than remaining in the
event queue. This tricky patch fixes the GC issue causing this.

scons: Ensure dictionary iteration is sorted by key

This patch adds sorting based on the SimObject name or parameter name
for all situations where we iterate over dictionaries. This should
ensure a deterministic and consistent order across the host systems
and hopefully avoid regression results differing across python
versions.

sim: Sort SimObject descendants and ports

This patch fixes a number of occurences where the sorting order of the
objects was implementation defined.

ruby: interface with classic memory controller
This patch is the final in the series. The whole series and this patch in
particular were written with the aim of interfacing ruby's directory controller
with the memory controller in the classic memory system. This is being done
since ruby's memory controller has not being kept up to date with the changes
going on in DRAMs. Classic's memory controller is more up to date and
supports multiple different types of DRAM. This also brings classic and
ruby ever more close. The patch also changes ruby's memory controller to
expose the same interface.

sim: EventQueue wakeup on events scheduled outside the event loop

This patch adds a 'wakeup' member function to EventQueue which should be
called on an event queue whenever an event is scheduled on the event queue
from outside code within the call tree of the gem5 event loop.

This clearly isn't necessary for normal gem5 EventQueue operation but
becomes the minimum necessary interface to allow hosting gem5's event loop
onto other schedulers where there may be calls into gem5 from external
code which schedules events onto an EventQueue between the current time and
the time of the next scheduled event.

The use case I have in mind is a SystemC hosting where the event loop is:

while (more events) {
wait(time_to_next_event or wakeup)
setCurTick
service events at this time
}

where the 'wait' needs to be woken up if time_to_next_event becomes shorter
due to a scheduled event from SystemC arriving in a gem5 object.

Requiring 'wakeup' to be called is a more efficient interface than
requiring all gem5 event scheduling actions to affect the host scheduler.

This interface could be located elsewhere, say on another global object,
or by being passed by the host scheduler to objects which will schedule
such events, but it seems cleanest to put it on EventQueue as it is
actually a signal to the queue.

EventQueue::wakeup is called for async_event events on event queue 0 as
it's only important that *some* queue be triggered for such events.

base: Reimplement the DPRINTF mechanism in a Logger class

This patch adds a Logger class encapsulating dprintf. This allows
variants of DPRINTF logging to be constructed and substituted in
place of the default behaviour.

The Logger provides a logMessage(when, name, format, ...) member
function like Trace::dprintf and a getOstream member function to
use a raw ostream for logging.

A class OstreamLogger is provided which generates the customary
debugging output with Trace::OstreamLogger::logMessage being the
old Trace::dprintf.

config: Add the ability to read a config file using C++ and Python

This patch adds the ability to load in config.ini files generated from
gem5 into another instance of gem5 built without Python configuration
support. The intended use case is for configuring gem5 when it is a
library embedded in another simulation system.

A parallel config file reader is also provided purely in Python to
demonstrate the approach taken and to provided similar functionality
for as-yet-unknown use models. The Python configuration file reader
can read both .ini and .json files.

C++ configuration file reading:

A command line option has been added for scons to enable C++ configuration
file reading: --with-cxx-config

There is an example in util/cxx_config that shows C++ configuration in action.
util/cxx_config/README explains how to build the example.

Configuration is achieved by the object CxxConfigManager. It handles
reading object descriptions from a CxxConfigFileBase object which
wraps a config file reader. The wrapper class CxxIniFile is provided
which wraps an IniFile for reading .ini files. Reading .json files
from C++ would be possible with a similar wrapper and a JSON parser.

After reading object descriptions, CxxConfigManager creates
SimObjectParam-derived objects from the classes in the (generated with this
patch) directory build/ARCH/cxx_config

CxxConfigManager can then build SimObjects from those SimObjectParams (in an
order dictated by the SimObject-value parameters on other objects) and bind
ports of the produced SimObjects.

A minimal set of instantiate-replacing member functions are provided by
CxxConfigManager and few of the member functions of SimObject (such as drain)
are extended onto CxxConfigManager.

Python configuration file reading (configs/example/read_config.py):

A Python version of the reader is also supplied with a similar interface to
CxxConfigFileBase (In Python: ConfigFile) to config file readers.

The Python config file reading will handle both .ini and .json files.

The object construction strategy is slightly different in Python from the C++
reader as you need to avoid objects prematurely becoming the children of other
objects when setting parameters.

Port binding also needs to be strictly in the same port-index order as the
original instantiation.

config: Add a --without-python option to build process

Add the ability to build libgem5 without embedded Python or the
ability to configure with Python.

This is a prelude to a patch to allow config.ini files to be loaded
into libgem5 using only C++ which would make embedding gem5 within
other simulation systems easier.

This adds a few registration interfaces to things which cross
between Python and C++. Namely: stats dumping and SimObject resolving

sim: draining bug for fast-forwaring multiple cores
fix draining bug where multiple cores hit max_insts_any_thread simultaneously

Committed by: Nilay Vaish <nilay@cs.wisc.edu>

config: Add Current as a parameter type

This patch adds the Python parameter type Current, which is used for
the DRAM power modelling (to start with). With this addition we avoid
implicit unit assumptions.

mem: Rename Bus to XBar to better reflect its behaviour

This patch changes the name of the Bus classes to XBar to better
reflect the actual timing behaviour. The actual instances in the
config scripts are not renamed, and remain as e.g. iobus or membus.

As part of this renaming, the code has also been clean up slightly,
making use of range-based for loops and tidying up some comments. The
only changes outside the bus/crossbar code is due to the delay
variables in the packet.

config: Cleanup .json config file generation

This patch 'completes' .json config files generation by adding in the
SimObject references and String-valued parameters not currently
printed.

TickParamValues are also changed to print in the same tick-value
format as in .ini files.

This allows .json files to describe a system as fully as the .ini files
currently do.

This patch adds a new function config_value (which mirrors ini_str) to
each ParamValue and to SimObject. This function can then be explicitly
changed to give different .json and .ini printing behaviour rather than
being written in terms of ini_str.

config: Fix vectorparam command line parsing

Parsing vectorparams from the command was slightly broken
in that it wouldn't accept the input that the help message
provided to the user and it didn't do the conversion
on the second code path used to convert the string input
to the actual internal representation. This patch fixes these bugs.

config: Add port splicing capability to PortRef class

The new configuration scripts need the ability to splice
a simobject between a pair of ports that are already connected.
The primary use case is when a CommMonitor needs to be
created after the system is configured and then spliced between
the pair of ports it will monitor.

config: Change parsing of Addr so hex values work from scripts

When passed from a configuration script with a hexadecimal value (like
"0x80000000"), gem5 would error out. This is because it would call
"toMemorySize" which requires the argument to end with a size specifier (like
1MB, etc).

This modification makes it so raw hex values can be passed through Addr
parameters from the configuration scripts.

ruby: message buffers: significant changes

This patch is the final patch in a series of patches. The aim of the series
is to make ruby more configurable than it was. More specifically, the
connections between controllers are not at all possible (unless one is ready
to make significant changes to the coherence protocol). Moreover the buffers
themselves are magically connected to the network inside the slicc code.
These connections are not part of the configuration file.

This patch makes changes so that these connections will now be made in the
python configuration files associated with the protocols. This requires
each state machine to expose the message buffers it uses for input and output.
So, the patch makes these buffers configurable members of the machines.

The patch drops the slicc code that usd to connect these buffers to the
network. Now these buffers are exposed to the python configuration system
as Master and Slave ports. In the configuration files, any master port
can be connected any slave port. The file pyobject.cc has been modified to
take care of allocating the actual message buffer. This is inline with how
other port connections work.

config: Add hooks to enable new config sys

This patch adds helper functions to SimObject.py, params.py and
simulate.py to enable the new configuration system. Functions like
enumerateParams() in SimObject lets the config system auto-generate
command line options for simobjects to be modified on the command
line.

Params in params.py have __call__() added
to their definition to allow the argparse module to use them
as a type to check command input is in the proper format.

cpu: Add flag name printing to StaticInst

This patch adds a the member function StaticInst::printFlags to allow all
of an instruction's flags to be printed without using the individual
is... member functions or resorting to exposing the 'flags' vector

It also replaces the enum definition StaticInst::Flags with a
Python-generated enumeration and adds to the enum generation mechanism
in src/python/m5/params.py to allow Enums to be placed in namespaces
other than Enums or, alternatively, in wrapper structs allowing them to
be inherited by other classes (so populating that class's name-space
with the enumeration element names).

config: Avoid generating a reference to myself for Parent.any

The unproxy code for Parent.any can generate a circular reference
in certain situations with classes hierarchies like those in ClockDomain.py.
This patch solves this by marking ouself as visited to make sure the
search does not resolve to a self-reference.

scons: Require SWIG >= 2.0.4 and remove vector typemaps

SWIG commit fd666c1 (*) made it unnecessary for gem5 to have these
typemaps to handle Vector types.

* https://github.com/swig/swig/commit/fd666c1440628a847793bbe1333c27dfa2f757f0

misc: Proper type check and import for PortRef

Rewriting the type checking around PortRef, which was interacting strangely
with other Python scripts.

Tested-by: stephan.diestelhorst@arm.com

stats: better error message for uninitialized statistic

As suggested by Nathan Binkert in 2008:
http://permalink.gmane.org/gmane.comp.emulators.m5.users/2676

misc: Fix -q (quiet) flag

Check the right flag.

base: add support for probe points and common probes

The probe patch is motivated by the desire to move analytical and trace code
away from functional code. This is achieved by the probe interface which is
essentially a glorified observer model.

What this means to users:
* add a probe point and a "notify" call at the source of an "event"
* add an isolated module, that is being used to carry out *your* analysis (e.g. generate a trace)
* register that module as a probe listener
Note: an example is given for reference in src/cpu/o3/simple_trace.[hh|cc] and src/cpu/SimpleTrace.py

What is happening under the hood:
* every SimObject maintains has a ProbeManager.
* during initialization (src/python/m5/simulate.py) first regProbePoints and
the regProbeListeners is called on each SimObject. this hooks up the probe
point notify calls with the listeners.

FAQs:
Why did you develop probe points:
* to remove trace, stats gathering, analytical code out of the functional code.
* the belief that probes could be generically useful.

What is a probe point:
* a probe point is used to notify upon a given event (e.g. cpu commits an instruction)

What is a probe listener:
* a class that handles whatever the user wishes to do when they are notified
about an event.

What can be passed on notify:
* probe points are templates, and so the user can generate probes that pass any
type of argument (by const reference) to a listener.

What relationships can be generated (1:1, 1:N, N:M etc):
* there isn't a restriction. You can hook probe points and listeners up in a
1:1, 1:N, N:M relationship. They become useful when a number of modules
listen to the same probe points. The idea being that you can add a small
number of probes into the source code and develop a larger number of useful
analysis modules that use information passed by the probes.

Can you give examples:
* adding a probe point to the cpu's commit method allows you to build a trace
module (outputting assembler), you could re-use this to gather instruction
distribution (arithmetic, load/store, conditional, control flow) stats.

Why is the probe interface currently restricted to passing a const reference:
* the desire, initially at least, is to allow an interface to observe
functionality, but not to change functionality.
* of course this can be subverted by const-casting.

What is the performance impact of adding probes:
* when nothing is actively listening to the probes they should have a
relatively minor impact. Profiling has suggested even with a large number of
probes (60) the impact of them (when not active) is very minimal (<1%).

config: Make the Clock a Tick parameter like Latency/Frequency

This patch makes the Clock a TickParamValue just like
Latency/Frequency. There is no longer any need to distinguish it
(originally needed to support multiplication).