SimObject outputs a warning when its parent is specified more than
once. The cause is most likely that there is unexpected param
specified in the constructor called in the Python interface.
This commit adds a note about this probable cause of this potential
error to the warning message.
Change-Id: I9b6bf5d5fb0c77bfdad5fde42e88f814e8a4b72b
Signed-off-by: Hoa Nguyen <hoanguyen@ucdavis.edu>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/38359
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The SmartDict, used by buildEnv, has been added long time ago for
the following reasons: (checking its documentation)
---
The SmartDict class fixes a couple of issues with using the content
of os.environ or similar dicts of strings as Python variables:
1) Undefined variables should return False rather than raising KeyError.
2) String values of 'False', '0', etc., should evaluate to False
(not just the empty string).
---
These are valid reasons, but I believe they should be addressed in
a more standardized way by using a common dictionary.
1) We should simply rely on dict.get
if buildEnv.get('KEY', False/None):
2) We should discourage the use of stringified False or 0.
If we are using a dictionary, can't we just pass those values as
booleans?
The SmartDict is basically converting every value into a
string ("Variable") at every access (__getitem__)
The Variable is a string + some "basic" conversion methods
What is the problem of passing every dict value as a string?
The problem is the ambiguity on the boolean conversion.
If a variable is modelling a boolean, we can return true if
the value is 'yes', 'true'... and false if the value is
'no', 'false' etc. We should raise an exception if it is
something different, like a typo (e.g.) 'Fasle'.
But if the variable is not modelling a boolean, we don't know
how to handle that. How should we convert 'mystring' ?
If we decide to treat 'mystring' as True (which is basically
what a str.__bool__ would return) we will break typoes detection,
as 'Fasle' will now be converted to True, rather than raising
an exception.
Change-Id: I960fbfb1ec0f703e1e372dd752ee75f00632acac
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/37775
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Hoa Nguyen <hoanguyen@ucdavis.edu>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The *vast* majority of SimObjects use the standard boilerplate version
of their Params::create() method which just returns new
ClassName(*this); Rather than force every class to define this method,
or annoy and frustrate users who forget and then get linker errors, this
change automates the default while leaving the possibility of defining a
custom create() method for non-default cases.
The situations this mechanism handles can be first broken down by
whether the SimObject class has a constructor of the normal form, ie one
that takes a const Params reference as its only parameter.
If no, then no default create() implementation is defined, and one
*must* be defined by the user.
If yes, then a default create() implementation is defined as a weak
symbol. If the user still wants to define their own create method for
some reason, perhaps to add debugging info, to keep track of instances
in c++, etc., then they can and it will override the weak symbol and
take precedence.
The way this is implemented is not straightforward. A set of classes are
defined which use SFINAE which either map in the real Params type or a
dummy based on whether the normal constructor exists in the SimObject
class. Then those classes are used to define *a* create method.
Depending on how the SFINAE works out, that will either be *the* create
method on the real Params struct, or a create method on a dummy class
set up to just absorb the definition and then go away. In either case the
create() method is a weak symbol, but in the dummy case it
doesn't/shouldn't matter.
Annoyingly the compiler insists that the weak symbol be visible. While
that makes total sense normally, we don't actually care what happens to
the weak symbol if it's attached to the dummy class. Unfortunately that
means we need to make the dummy class globally visible, although we put
it in a namespace to keep it from colliding with anything useful.
Change-Id: I3767a8dc8dc03665a72d5e8c294550d96466f741
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/35942
Reviewed-by: Gabe Black <gabe.black@gmail.com>
Reviewed-by: Richard Cooper <richard.cooper@arm.com>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The create() method on Params structs usually instantiate SimObjects
using a constructor which takes the Params struct as a parameter
somehow. There has been a lot of needless variation in how that was
done, making it annoying to pass Params down to base classes. Some of
the different forms were:
const Params &
Params &
Params *
const Params *
Params const*
This change goes through and fixes up every constructor and every
create() method to use the const Params & form. We use a reference
because the Params struct should never be null. We use const because
neither the create method nor the consuming object should modify the
record of the parameters as they came in from the config. That would
make consuming them not idempotent, and make it impossible to tell what
the actual simulation configuration was since it would change from any
user visible form (config script, config.ini, dot pdf output).
Change-Id: I77453cba52fdcfd5f4eec92dfb0bddb5a9945f31
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/35938
Reviewed-by: Gabe Black <gabeblack@google.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Occasionally gem5's stdout/stderr, when run within the TestLib
framework, will be shuffled. This is resolved by flushing the
stdout/stderr buffer before and after simulation.
In addition to this, the verifier.py has been improved to remove
boilerplate gem5 code from the stdout comparison.
Change-Id: I04c8f9cee4475b8eab2f1ba9bb76bfa3cfcca6ec
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/34995
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The debug flags API has a couple of quirks that should be cleaned
up. Specifically:
* Only CompoundFlag should expose a list of children.
* The global enable flag is just called "active", this isn't very
descriptive.
* Only SimpleFlag exposed a status member. This should be in the base
class to make the API symmetric.
* Flag::Sync() is an implementation detail and needs to be protected.
Change-Id: I4d7fd32c80891191aa04f0bd0c334c8cf8d372f5
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/34118
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
There are times when we need to change the name of parameter, but this
breaks the external-facing python API used in configuration files. Using
this "type" for a parameter will warn users that they are using the old
name, but allow for backwards compatibility.
Declaring a SimObject parameter of type `DeprecatedParam` allows the
python configuration files to use the old name transparently. This
leverages some of the SimObject magic to remember the names of
deprecated parameters and the DeprecatedParam object stores the
"translation" from old name to new name.
This has been tested with Ports, "normal" parameters, and SimObject
parameters. It has not been tested with checkpointing as there are no
checkpointing tests in gem5 right now. The testing was manually adding
some deprecated params and checking that config scripts still run
correctly that use the old, deprecated, variables.
Change-Id: I0465a748c08a24278d6b1a9d9ee1bcd67baa5b13
Signed-off-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/31954
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The decorator creates two versions of a class, adding it to the Params
dict multiple times which generates an annoying warning. Alternatively,
the with_metaclass mechanism sets up an alternative base class which
does not create the extra class and doesn't generate the warning.
It may be the case that this generates extra classes which just don't
lead to a warning? Or in other words, would we then have Params types
with weird, internal names generated by six? Hopefully not, but that may
be preferable to the annoying warnings, especially when running tests
which run gem5 many times.
Change-Id: I9395cde3fc95126c0a0c4db67fc5b0c6bf2dd9ed
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/33276
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Current compareVersions() fails in this case:
compareVersions("10", "10.0") return -1 while it should be 0.
This at least is causing a systemc compiling issue.
This problem causes by the comparison algorithm. The algorithm
turns the versions in two lists, and compares the corresponding
elements of the two lists up to the last element of the shorter
list. If all elements are equal, the longer list will be
determined to be the more recent version. Hence, this algorithm
determines "10.0" to be more recent to "10".
This commit addresses this issue by making the version lists
have the same length by adding 0 to the shorter list.
JIRA: https://gem5.atlassian.net/browse/GEM5-715
Change-Id: I859679185ac67e1b4d327d8803699cc5e399fa8c
Signed-off-by: Hoa Nguyen <hoanguyen@ucdavis.edu>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/32014
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This commit makes it possible to make invocations such as:
gem5.opt se.py --stats-root 'system.cpu[:].dtb' --stats-root 'system.membus'
When --stats-root is given, only stats that are under any of the root
SimObjects get dumped. E.g. the above invocation would dump stats such as:
system.cpu0.dtb.walker.pwrStateResidencyTicks::UNDEFINED
system.cpu1.dtb.walker.pwrStateResidencyTicks::UNDEFINED
system.membus.pwrStateResidencyTicks::UNDEFINED
system.membus.trans_dist::ReadReq
but not for example `system.clk_domain.clock`.
If the --stats-root is given, only new stats as defined at:
Idc8ff448b9f70a796427b4a5231e7371485130b4 get dumped, and old ones are
ignored. The commits following that one have done some initial conversion
work, but many stats are still in the old format.
Change-Id: Iadaef26edf9a678b39f774515600884fbaeec497
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/28628
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The alignment spaces in stats.txt takes up a lot of space and increases
simulation time, this commit adds the option to disable them with:
--stats-file stats.txt?spaces=False
Sample old lines with ?desc=False:
system.cpu.op_class::FloatMultAcc 0 0.00% 65.92%
system.cpu.op_class::FloatDiv 0 0.00% 65.92%
Sample new lines with ?desc=False;spaces=False:
system.cpu.op_class::FloatMultAcc 0 0.00% 65.92%
system.cpu.op_class::FloatDiv 0 0.00% 65.92%
On a 1000 dumpstats m5op loop spaces=False reduces:
* size: from 38MB to 20MB
* time: from 4.5s to 3.5s
Change-Id: Ib738b996b5646c329094cf61aaa1d977e844e759
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/28627
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This commit changes m5's tick rounding mechanism from python's round()
to python's ceil() function.
Currently, non intergral ticks are rounded by round() function in python.
In python2, this function rounds values >= 0.5 to 1. However, in python3,
0.5 is rounded to 0. This causes the function to return 0 ticks for
non-zero second values, which doesn't make sense, and also causes
several tests to fail.
ceil() function is now used to round up the tick values. This makes more
sense as non-zero second values won't be rounded to zero in any cases.
Signed-off-by: Hoa Nguyen <hoanguyen@ucdavis.edu>
Change-Id: I14c43e38e8c678f77baf13407f7eeff4b86f1014
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/29372
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
By default, DOT configs are always generated when pydot is present.
This change allows a user to pass an empty --dot-config='' to disable
generating the DOT configuration. This can be useful to save space, or
to reduce Gem5 startup time when running many small regression tests.
This brings the behavior in-line with providing an empty
--dump_config='' and/or --json_config='' which similarly disables
generation of those output files.
Change-Id: I5bf39fda0409b948a8d14f3afa95db8fc78de6ee
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/29232
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
When the internal utility function make_version_list sees a string, it
tries to convert it into a list using the map() function. In python 3,
that returns an iterator. The following call to zip() will consume those
iterators, and then the following calls to len() will die because they
don't work on map iterators.
This is only a problem if all the common components of the version lists
are equal, and the comparison needs to then check if one of the lists
was equal to the other but with more components. When versions are
equal, for instance when compiling with the oldest supported version of
gcc (4.8.0) this error surfaces and breaks our scons build.
A simple fix is to just wrap the call to map() with list() to convert
the iterator to a flat list, making the other logic work as before.
Change-Id: If9dc5cd7fff70c21229ac3dd9a017edeccd26148
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/28309
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Python 3 uses the concepts of two different types:
text and binary strings.
Those cannot be implicilty combined (as it was happening in python2) and
in order to be used together one of them must be converted to the other
type:
* Text can be encoded into Bytes via the encode() method
* Bytes can be decoded to Text using the decode() method
By default encode/decode will assume UTF-8 format
JIRA: https://gem5.atlassian.net/browse/GEM5-345
Change-Id: I1bdf7db17b49cc109239fd5f44791769370853f8
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/26250
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
* dict methods dict.keys(), dict.items() and dict.values()
return "views" instead of lists
* The dict.iterkeys(), dict.iteritems() and dict.itervalues()
methods are no longer supported.
* map() and filter() return iterators.
* range() now behaves like xrange() used to behave, except it works with
values of arbitrary size. The latter no longer exists.
* zip() now returns an iterator.
Change-Id: Id480018239db88d7f5d60588c93719056de4a0c0
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/26248
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Python 2.x and Python 3 use different meta class syntax. Fix this by
implementing meta classes using the add_metaclass decorator in the six
Python library.
Due to the way meta classes are implemented in six,
MetaParamValue.__new__ seems to be called twice for some classes. This
triggers an assertion which when param that checks that Param types
have only been registered once. I have turned this assertion into a
warning.
The assertion was triggered in params.CheckedInt and params.Enum. It
seems like the cause of the issue is that these classes have their own
meta classes (CheckedIntType and MetaEnum) that inherit from
MetaParamValue and a base class (ParamValue) that also inherits from
MetaParamValue.
Change-Id: I5dea08bf0558cfca57897a124cb131c78114e59e
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/26083
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
In python 3, the curses escape sequences are bytes objects and not
strings, making them unsuitable to concatenate to strings which are
being print()-ed. This uses the decode() method to turn them from bytes
objects into string objects, assuming they represent UTF-8. In python
2, bytes objects and strings are treated interchangeably, and so this
isn't necessary.
Change-Id: Ifc5d788e1c62751090a350d3a064e89f434559e8
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/23265
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This is the second step towards being able to run dynamically linked
applications when the guest ISA != than host ISA.
Once the guest interpreter is loaded to memory, we are able to redirect
shared object loads through the redirectPath interface.
How do we load the guest interpreter?
The elf file is for example asking for the /lib/ld-linux-aarch64.so
interpreter.
That would point to a valid dynamic linker/loader if guest ISA == host
ISA, but if we are running on X86 we should point to the guest
(aarch64 in the example) toolchain wherever it is installed.
This patch is adding the --interp-dir option to point to the parent
folder of the guest /lib in the host fs.
Change-Id: Id27b97c060008d2e847776a49323d45c8809a27f
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/23066
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>
These tests assume the "end address" is not included in the range. This
exposed some bugs in addr_range.hh which have been fixed. Where
appropriate code comments in addr_range.hh have been extended to improve
understanding of the class's behavior.
Hard-coded AddrRange values in the project have been updated to take
into account that end address is now exclusive. The python params.py
interface has been updated to conform to this new standard.
Change-Id: Idd1e75d5771d198c4b8142b28de0f3a6e9007a52
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/22427
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Descriptions were previously printed on one line, unless explicitly broken
when writing the description of the Sim-Object. In this commit, line
wrapping is enabled when printing these descriptions. Developers, when
writing the Sim-Object descriptions, may now over multiple lines with
triple double-quotes and still have the description output correctly when
viewing the Sim-Objects within the CLI.
E.g.: X86System previously had the following load_addr_mask component which
was output as:
load_addr_mask
default: 18446744073709551615
desc: Address to mask loading binaries with, if 0, system \
auto-calculates the mask to be the most restrictive, otherwise it obeys a \
custom mask.
This was defined by the developer via:
load_addr_mask = Param.UInt64(0xffffffffffffffff,
"Address to mask loading binaries with, if 0, system "
"auto-calculates the mask to be the most restrictive, "
"otherwise it obeys a custom mask.")
This is now displayed as:
load_addr_mask
default: 18446744073709551615
desc: Address to mask loading binaries with, if 0,
system auto-calculates the mask to be the most
restrictive, otherwise it obeys a custom mask.
JiraID: Gem5-57
Built: Linux (GCC)
Tested: Ran quick tests for X86, ARM, and RISC-V
Change-Id: If012304e50af60f6ba10c1fa2b44da8bac1c09cf
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21179
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Some objects need to know that we are about to dump stats to perform
prepare statistics. This is currently done by registering a callback
with the stat system. Expose this callback as a virtual method
in Stats::Group to make this pattern more convenient.
Change-Id: I5aa475b7d04c288e45f5f413ab7a1907b971dae5
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21139
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
New-world stats didn't implement the old gem5 quirk where the index of
an element in a vector of size 1 is ignored. This affects the object
path when printed in a stat file. Implement the same quirk as the
original code to make sure names of old- and new-world stats are
compatible.
Change-Id: I12696d40baaed2d0bb1ef061e87c3b1d0f4bb4b1
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21163
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
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>
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>
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>