These can now be built without referring to anything in ThreadContext
and so can be built even with the NULL ISA. This means the pcEventQueue
can be unconditionally built into the System class. Even though the
pcEventQueue is going away, this still makes it possible for System to
be a PCEventScope unconditionally.
Change-Id: Ia342bb7972b1b5ce95033176d72af4bfa343560f
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/22104
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
FutexMap::wakeup is called when the futex(TGT_FUTEX_WAKE syscall is done.
FutexMap maintains a list of sleeping threads for each futex address
added on FutexMap::suspend, and entries are removed from the list
at FutexMap::wakeup.
The problem is that this system was not taking into account that threads
can be woken up by memory accesses to locked addresses via the path:
SimpleThread::activate
BaseSimpleCPU::wakeup
AbstractMemory::checkLockedAddrList
AbstractMemory::access
DRAMCtrl::recvAtomic
CoherentXBar::recvAtomicBackdoor
SimpleExecContext::writeMem
which happens on trivial pthread examples on ARM at least. The instruction
that locked memory in those test cases was LDAXR.
This could lead futex(TGT_FUTEX_WAKE to awake a thread that is already
awake but is first on the sleeping thread list, instead of a sleeping one,
which can lead all threads to incorrectly sleep and in turn to
"simulate() limit reached".
To implement this, ThreadContext::activate return now returns a boolean
that indicates if the state changed. suspend and halt are also modified
to also return a boolean in the same case for symmetry, although this is
not strictly necessary for the current patch.
Change-Id: Ia6b4d3e6148c64721d810b8f1fffaa208a394b06
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21606
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This queue was set up to allow triggering events based on the total
number of instructions executed at the system level, and was added in
a change which added a number of things to support McPAT. No code
checked into gem5 actually schedules an event on that queue, and no
code in McPAT (which seems to have gone dormant) either downloadable
from github or found in ext modify gem5 in a way that makes it use
the instEventQueue.
Also, the KVM CPU does not interact with the instEventQueue correctly.
While it does check the per-thread instruction event queue when
deciding how long to run, it does not check the instEventQueue. It will
poke it to run events when it stops for other reasons, but it may (and
likely will) have run beyond the point where it was supposed to stop.
Since this queue doesn't seem to actually be used for anything, isn't
being used properly in all cases anyway, and adds overhead to all the
CPU models, this change eliminates it.
Change-Id: I0e126df14788c37a6d58ca9e1bb2686b70e60d88
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21783
Maintainer: Gabe Black <gabeblack@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Tiago Mück <tiago.muck@arm.com>
Tested-by: kokoro <noreply+kokoro@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 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>
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>
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>
The base Port class can keep track of its peer, and also whether it's
connected. This is partially delegated away from the port subclasses
which still keep track of a cast version of their peer pointer for
their own conveneince, so that it can be used by generic code. Even
with the Port mechanism's new flexibility, each port still has
exactly one peer and is either connected or not based on whether there
is a peer currently.
Change-Id: Id3228617dd1604d196814254a1aadeac5ade7cde
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20232
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Gabe Black <gabeblack@google.com>
This hook will let them implement whatever additional behavior is
necessary for when the clock changes.
An alternative design for this might have made the "update" function
virtual, and required anyone overriding it to call into the base class.
I think that would be an inferior design for two reasons. First, the
subclass author might forget to call update. Second, while it might
*seem* like this would have some performance benefit since you wouldn't
call into the virtual function and then call update, incurring the
function call overhead twice, you're going to call into update once
regardless, and then you're either going to call the virtual funciton
which does nothing (the norm) or does something. In either case you
call the same functions the same number of times.
There may be a slight penalty in code size since the call to update
may be inlined in the call sights before the virtual function, and
there will almost certainly be more of those than there would be
implementations of the virtual function, but that should be negligable
when compared to gem5's size as a whole.
Change-Id: Id25a5359f2b1f7e42c6d1dcbc70a37d3ce092d38
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20089
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Chun-Chen TK Hsu <chunchenhsu@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Reviewed-by: Srikant Bharadwaj <srikant.bharadwaj@amd.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
The fstat64 system call does an upcast on entries in the file
descriptor array to check if the file descriptor has a backing
host-filesystem file opened. It does so because it needs to pass
the host fd into the fstat call (since we rely on the host
filesystem to service filesystem system calls).
The upcast was overly specific. This changeset alters the system
call to use the most general base class of the file descriptor
entries that can satisfy the code.
Change-Id: I10daf820257cea4d678ee6917e01e9cc9cd1cf5e
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17110
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
This expands those functions into code which extracts the virt proxy
and then uses the appropriate method on it. This has two benefits.
First, the Copy* functions where mostly redundant wrappers around the
methods the proxy port already had. Second, using them forced a
particular port which might not actually be what the user wanted.
Change-Id: I62084631dd080061e3c74997125164f40da2d77c
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18575
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Set the default release to that single value for all ISAs.
glibc has checks for the kernel version based on uname, and refuses
to start any syscall emulation programs if those checks don't pass with
error:
FATAL: kernel too old
The ideal solution to this problem is to actually implement all missing
system calls for the required kernel version and bumping the release
accordingly.
However, it is very hard to implement all missing syscalls and verify
compliance.
Previously, we have simply bumped the version manually from time to
time when major glibc versions started breaking.
This commit alleviates the problem in two ways.
Firstly, having a single kernel version for all versions means that it is
easier to bump all versions at once.
Secondly, it makes it is possible to set the release with a parameter,
which in turn can be set from the command line with:
se.py --param 'system.cpu[:].workload[:].release = "4.18.0"'
Change-Id: I9e3c31073bfe68735f7b0775c8e299aa62b98222
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17849
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The system calls had four parameters. One of the parameters
is ThreadContext and another is Process. The ThreadContext
holds the value of the current process so the Process parameter
is redundant since the system call functions already have
indirect access.
With the old API, it is possible to call into the functions with
the wrong supplied Process which could end up being a confusing
error.
This patch removes the redundancy by forcing access through the
ThreadContext field within each system call.
Change-Id: Ib43d3f65824f6d425260dfd9f67de1892b6e8b7c
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/12299
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Currently, the open system call implementation in SE mode
treats /sys/ as a special path that is opened using a
special open handler. The ROC runtime, however, reads
several files in /sys/ that are supported via path
redirection. Here we remove /sys/ from the special files
so that the necessary files may be read via path
redirection.
Change-Id: Ifdab38ea1e6cc486ad43aec96b6e032fe63f137d
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/12127
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This gets rid of the big mass of #if-s around headers and around the
code which creates an object file.
As a nice side bonus, this also means that in addition to supporting
multiple OS/arch combinations simultaneously, the object file loader
could support multiple ISAs simultaneously as well, since each could
load and set up its object file loaders indepedently and without the
base process classes knowledge/involvement.
Change-Id: I0a19ad06e30e9062a96d27f00b66756eb3a595ba
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18631
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
54c77aa055 introduced a bug which manifests as cyclical
dependency on a member initialization for the Process
class.
The current working directory (cwd) parameter is passed into
Process to initialize both the target and host versions of the
cwd. (The target and host versions may differ if the faux
filesystem is used.) The host cwd init invoked methods which
rely on the host cwd already being initialized. To avoid the
bug, the code will now rely on using the targets cwd version,
but will issue checks against the redirect paths.
Change-Id: I4ab644a3e00737dbf249f5d6faf20a26ceb04248
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18448
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Then cast to the ISA specific type when necessary. This removes
(mostly) an ISA specific aspect to some of the interfaces. The ISA
specific version of the kernel stats still needs to be constructed and
stored in a few places which means that kernel_stats.hh still needs to
be a switching arch header, for instance.
In the future, I'd like to make the kernel its own object like the
Process objects in SE mode, and then it would be able to instantiate
and maintain its own stats.
Change-Id: I8309d49019124f6bea1482aaea5b5b34e8c97433
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18429
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
The AuxVector type has a bunch of accessors which just give access to
the underlying variables through references. We might as well just make
those members accessible directly.
Also, the AuxVector doesn't need to handle endianness flips itself. We
can tell the byteswap mechanism how to flip an AuxVector, and let it
handle that for us.
This gets rid of the entire .cc file which was complicated by trying
to both hide the ISA specific endianness translations, and instantiate
templated functions in a .cc.
Change-Id: I433cd61e73e0b067b6d628fba31be4a4ec1c4cf0
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18373
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
These selected their behavior based on ifdefs and had to be disabled
when on the NULL ISA. The versions which take an explicit endianness
have been renamed to just read/write instead of readGtoH and writeHtoG
since the direction of the translation is obvious from context.
Change-Id: I6cfbfda6c4481962d442d3370534e50532d41814
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18372
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
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>
This change introduces the concept of a faux-filesystem.
The faux-filesystem creates a directory structure in m5out
(or whatever output dir the user specifies) where system calls
may be redirected.
This is useful to avoid non-determinism when reading files
with varying path names (e.g., variations from run-to-run if
the simulation is scheduled on a cluster where paths may change).
Also, this changeset allows circumventing host pseudofiles which
have information specific to the host processor (such as cache
hierarchy or processor information). Bypassing host pseudofiles
can be useful when executing runtimes in the absence of an
operating system kernel since runtimes may try to query standard
files (i.e. /proc or /sys) which are not relevant to an
application executing in syscall emulation mode.
Change-Id: I90821b3b403168b904a662fa98b85def1628621c
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/12119
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>
