Current loader is performing a linear scan of the section table for
every segment in the elf since it is naming every segment after the
sections it contains. With this patch we are just naming segments
after their index.
This is in any case how they are referenced when a readelf --segments
command is issued on the elf file.
Change-Id: I599400fcdfc0b80ac64632aba36781bd876777f0
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21999
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This abstraction will allow scheduling PCEvents for a particular
ThreadContext, all contexts on a CPU, all contexts in a system, etc.,
and delegates scheduling and removing events to each particular scope.
Right now the PCEventQueue is the only implementor of the PCEventSCope
interface.
Change-Id: I8fb62931511136229915c2e19d36aae7ffdec9df
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/22099
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Adding these tests supercedes the unittest/strnumtest.cc
and unittest/tokentest.cc tests. They have thereby been removed.
Function "to_number" in base/str.hh previously failed to cast negative
float/double numbers. This was due to the use of
std::numeric_limits<T>::min() instead of std::numeric_limits<T>::lowest()
to determine whether a string-to-float/double conversion was
"Out of range". Tests "StrTest.ToNumberFloatNegative" and
"StrTest.ToNumberDoubleNegative" exposed this bug. It has been fixed.
Methods "split_first" and "split_last" in base/str.hh have had their
documentation updated to remove abiguity in their functionality.
Change-Id: I16e0fe40d884e22dd010db4045857eb6e7f33d4a
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/22084
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>
There are cases where the memory system needs to reason about
channel-local addresses. These are currently represented using the
Addr and AddrRange classes. This is not ideal since it doesn't provide
any type safety when working with global addresses and channel-local
addresses. This is particularly problematic when porting existing
components to work in multi-channel configurations.
This changeset introduces the new ChannelAddr and ChannelAddrRange
classes. These classes encapsulate channel-local addresses in a
contiguous address space. These can, for example, be used in a memory
controller to represent a flat address space when calculating timings
or in a sectored cache.
Change-Id: I45d4061ebc8507a10d0a4577b28796dc5ec7a469
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21600
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This change creates a distinction between object files which hold
executable code, and flat files which don't. The first type of files
have entry points, symbols, etc., while the others are just blobs which
can be shoved into memory. Rather than have those aspects but stub
them out, this change creates a new base class which simply doesn't
have them.
This change also restructures the ELF loader since it's main function
was quite long and doing multiple jobs.
It stops passing the architecture and operating system to the
ObjectFile constructor, since those might not be known at the very top
of the constructor. Instead, those default to Uknown*, and then are
filled in in the constructor body if appropriate. This removes a lot
of plumbing that was hard to actually use in practice.
It also introduces a mechanism to collect generic object file formats
so that they can be tried one by one by the general createObjectFile
function, rather than listing them all there one by one. It's unlikely
that new types of object files will need to be added in a modular way
without being able to modify the core loader code, but it's cleaner to
have that abstraction and modularization like is already there for
process loaders.
Finally, to make it possible to share the code which handles zipped
files for both true object files and also files which will be loaded
into memory but are just blobs, that mechanism is pulled out into a
new class called ImageFileData. It holds a collection of segments
which are set up by the object file and may refer to regions of the
original file, buffers maintained elsewhere, or even nothing to support
bss-es. shared_ptr is used to make it easier to keep track of that
information without having to do so explicitly or worry about deleting
a buffer before everyone was done using it.
Change-Id: I92890266f2ba0a703803cccad675a3ab41f2c4af
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21467
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>
A memory image can be described by an object file, but an object file
is more than a memory image. Also, it makes sense to manipulate a
memory image to, for instance, change how it's loaded into memory. That
takes on larger implications (relocations, the entry point, symbols,
etc.) when talking about the whole object file, and also modifies
aspects which may not need to change. For instance if an image needs
to be loaded into memory at addresses different from what's in the
object file, but other things like symbols need to stay unmodified.
Change-Id: Ia360405ffb2c1c48e0cc201ac0a0764357996a54
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21466
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>
The interpreter is a separate object file, and while it's convenient to
hide loading it in the code which loads the main object file, it breaks
the conceptual abstraction since you only asked it to load the main
object file.
Also, this makes every object file format reimplement the idea of
loading the interpreter. Admittedly only ELF recognizes and sets up
an interpreter, but other formats conceptually could too.
This does move that limitted hypothetical redundancy out of the object
file formats and moves it into the process objects, but I think
conceptually that's where it belongs. It would also probably be pretty
easy to add a method to the base Process class that would handle
loading an image and also the interpreter image.
This change does not (yet) separate reading symbol tables.
Change-Id: I4a165eac599a9bcd30371a162379e833c4cc89b4
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21465
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Gabe Black <gabeblack@google.com>
The ObjectFile class has hardcoded assumptions that there are three
segments, text, bss and data. There are some files which have one
"segment" like raw files, where the entire file's contents are
considered a single segment. There are also ELF files which can have
an arbitrary number of segments, and those segments can hold any
number of sections, including the text, data and/or bss sections.
Removing this assumption frees up some object file formats from having
to twist themselves to fit in that structure, possibly introducing
ambiguities when some segments may fulfill multiple roles.
Change-Id: I976e06a3a90ef852b17a6485e2595b006b2090d5
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21463
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Gabe Black <gabeblack@google.com>
A pointer to it was set up in the MIPS and RISCV system classes, but
nothing ever set that pointer. The class was put in base/loader, but
didn't have anything to do (as far as I can see) with loading anything
it had a loadSegments method, but was not a subclass of ObjectFile.
Change-Id: I4b711a31df20e20ffc306709227f60aa020fca15
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21464
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
ELF is, in my opinion, the most important object file format gem5
currently understands, and in ELF terminolgy the blob of data that
needs to be loaded into memory to a particular location is called a
segment. A section is a software level view of what's in a region
of memory, and a single segment may contain multiple sections which
happen to follow each other in memory.
Change-Id: Ib810c5050723d5a96bd7550515b08ac695fb1b02
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21462
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Gabe Black <gabeblack@google.com>
If the %p format is used, char * arguments should be printed as the
hex value of their pointer, not as strings. Unfortunately blindly
passing them to an ostream using << will not do that. This change adds
some casting in that case to ensure that they're treated as numbers and
not as strings.
Change-Id: If02bae6d5e468b352266702fcba62b6beddffcbd
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21459
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.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>
This change is based on modify the way we move the AtomicOpFunctor*
through gem5 in order to mantain proper ownership of the object and
ensuring its destruction when it is no longer used.
Doing that we fix at the same time a memory leak in Request.hh
where we were assigning a new AtomicOpFunctor* without destroying the
previous one.
This change creates a new type AtomicOpFunctor_ptr as a
std::unique_ptr<AtomicOpFunctor> and move its ownership as needed. Except
for its only usage when AtomicOpFunc() is called.
Change-Id: Ic516f9d8217cb1ae1f0a19500e5da0336da9fd4f
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20919
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Info::setName() performs a sanity check to ensure that the same stat
name isn't used twice. This doesn't work for new-style stats with a
parent group since the name is only unique within the group. Disable
the check for new-style stats since these usually use names generated
from member variable names.
Change-Id: I590abe6040407c6a4fe582c0782a418165ff5588
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20760
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>
When using the HDF5 stats backend, we currently pass the filename from
the command line straight to the HDF5 library. This behaviour is
different from the expected behaviour when using plain text stat files
where relative paths are resolved relative to simout. This change adds
support for resolving hdf5 paths relative to simout.
Change-Id: I09cb0b7468735e697125eda7f04c5a85725ca8d0
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20508
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
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>
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>
In some cases, the point where you create a Coroutine is not the same as
where you want to start running it (and want it to switch back to). This
leads to the unnecessary overhead of switching in and out of the
Coroutine. This change adds an optional boolean argument to the
constructor for the Coroutine class to allow for overriding the default
behavior of running the Coroutine upon creation, which in specific cases
can be used to avoid the unnecessary overhead and improve simulator
performance.
Change-Id: I044698f85e81ee4144208aee30d133bcb462d35d
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18588
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>
AddrRange does not attempt to merge interleaved address ranges if it
has only one of the ranges.
This is needed to allow XBars to accept request targeting only one
part of a interleaved address range. A use case for this would be
modeling distributed LLCs in which a XBar is used solely to
encapsulate the snoop filter of a single LLC slice.
Change-Id: If71c9cf1444ee11916611afb51eab3a4f1d93985
Signed-off-by: Tiago Muck <tiago.muck@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18788
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>
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>