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>

sim: Add a << overload for the Port class which prints its name.

This makes it easier/less verbose to print the name of a port, it's
most important and identifying feature, in a DPRINTF or other stream
based output.

Change-Id: I050d102844612577f9a83d550e619736507a6781
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20234
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

sim: Add a takeOverFrom method to the base Port class.

This makes it easier, safer, and less verbose to swap out ports when
a CPU takes over for another CPU, for instance.

Change-Id: Ice08e4dcb4b04dc66b1841331092a78b4f6f5a96
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20233
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Gabe Black <gabeblack@google.com>

mem, sim, systemc: Reorganize Port and co.s bind, unbind slightly.

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>

sim: Add a hook Clocked objects can implement for frequency changes.

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>

sim: Clean up some mild style bugs in clocked_object.hh.

Clean up some formatting, and also remove redundant inline keywords.
A function defined in place in a class definition is already
automatically inline.

Change-Id: Iaad3a8dda6498c6a6068c2aabc9d6eb11f3d2eb2
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20088
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

sim-se: rename Process::setpgid member

The getter methods to access these types of members do not
have a 'get' string in the method names. To make the interface
a bit more consistent, remove the 'set' part of the member name.

Change-Id: I04c56bd9d9feb1cf68ff50a1152083ea57ea7c62
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20008
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>

sim-se: minor refactor for ProcessParams::create

Remove the nullptr initialization and change the message
for object file failure.

Change-Id: I14b80b47b65893c55810e7f715c1b8fc643c5125
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19949
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

sim-se: remove unused parameter

The init function which processes invoke on their page tables
has a thread context pointer parameter. The parameter is not
used by the code so remove it.

Change-Id: Ic4766fbc105d81c1c9ee4b5c0f428497dff2ab30
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19948
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

sim-se: add new getpgrp system call

This changeset adds new (relatively simple) system call
support. The getpgrp call returns a thread context's
pgid.

Change-Id: I361bdbfb9c01b761ddd5a4923d23f86971f8d614
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17111
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Ayaz Akram <yazakram@ucdavis.edu>

sim-se: adding pipe2 syscall

pipe2 builds on top of the pipe syscall implementation by
adding some extra flags for the files (to avoid have to
make separate calls to fcntl).

Change-Id: I88cf6f1387b9d14e60b33a32db412da9ed93a3e6
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/12310
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>

sim-se: small refactor on pipe syscall

Change-Id: I02ffb1c4af980554ff12ac7d11d32ba80fe261c5
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/12308
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>

sim-se: small performance optimization

A local variable was being set inside a loop when it should
have been set outside the loop. This changeset moves the
variable to the appropriate place.

Change-Id: If7655b501bd819c39d35dea4c316b4b9ed3173a2
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17108
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

sim-se: fstat64 bugfix

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>

sim-se: add new option to getrlimit syscall

The NPROC option was not serviced by the getrlimit syscall.
This changeset adds in the necessary code to service the option.

Change-Id: I679d3949c3bbb0628188f4e33034028d7726fdcb
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17109
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>

sim: Add getter to fault virtual address

Change-Id: Ifd493aee9e78b0b4ddcc71e90f48679543acb861
Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19176
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch, base, cpu, gpu, sim: Merge getMemProxy and getVirtProxy.

These two functions were performing the same function but had two
different names for historical reasons. This change merges them
together, keeping the getVirtProxy name to be consistent with the
getPhysProxy method used to get a non-translating proxy port.

Change-Id: Idd83c6b899f9343795075b030ccbc723a79e52a4
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18581
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

cpu, sim: Return PortProxy &s from all the proxy accessors.

This is a step towards merging the accessors for SE and FS modes.

Change-Id: I76818ab88b97097ac363e243be9cc1911b283090
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18579
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch, base, sim: Demote (SE|FS)TranslatingPortProxy &s to PortProxy &s.

Al(most) all of the interesting differences between the two classes
have been removed. There are some control methods which are still
specific to each type which may require treating them as their true
type, but most code that consumes them doesn't need to worry about
which is which.

Change-Id: Ie592676f1e496c7940605b66e55cd7fae18e59d6
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18577
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch, base, sim: Replace Copy(String)?(In|Out) with equivalent code.

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>

sim-se: add a release parameter to Process.py

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>

arch, base, dev, sim: Remove now unnecessary casts from PortProxy methods.

Change-Id: Ia73b2d86a10d02fa09c924a4571477bb5f200eb7
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18572
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

sim-se: change syscall function signature

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>

sim-se: remove /sys from special paths

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>

sim: Make the Process create function use the object loader mechanism.

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>

arch, base, cpu, dev, mem, sim: Remove #if 0-ed out code.

This code will be preserved through version control, but otherwise
creates clutter and will rot in place since it's never compiled.

Change-Id: Id265f6deac445116843956ea5cf1210d8127274e
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18608
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

sim-se: correct statfs inclusion on !linux host

- Added missing header
- Fixed typo on __linux__ macro conditional
- s/ifdef/if defined/g for consistency

Change-Id: I83b69856e5ec8b23b707642c0e14216cf62db31e
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18668
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

sim-se: fix a few bugs/warns from GCC 6

Change-Id: Ib2ad860324fd234b23262d141be3e82628ff61f0
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/12126
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

sim-se: add eventfd system call

Change-Id: I7aeb4fe808d0c8f2fb8041e3662d330d8458f09c
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/12125
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Ciro Santilli <ciro.santilli@arm.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

sim-se: use DPRINTF_SYSCALL for ioctl/wait4

Change-Id: I4fbaf1a0653f13ae964a2574cc26bbaac2dc0686
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/12124
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

sim-se: bugfix for 54c77aa055e

54c77aa055e 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>

arch: cpu: Track kernel stats using the base ISA agnostic type.

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>

sim-se: add socket ioctls

The OpenMPI 1.8.2 runtime needs the ioctl code
included in this patch to issue socket operations
on the host machine.

Change-Id: I687b31f375a846f0bab2debd9b9472605a4d2c7d
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/12123
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

sim-se: create Proc out files in out dir

Redirected output files from Process objects were being
created in the current directory instead of in the
output directory.

Change-Id: Ieb6ab5556fbcc811f4f24910da247d4dcdbc71bd
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/12122
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch, sim: Simplify the AuxVector type.

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>

mem: Remove the ISA specialized versions of port proxy's read/write.

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>

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>

sim-se: add a faux-filesystem

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>

sim-se: Enhance clone for X86KvmCPU

This changeset enables clone to work with X86KvmCPU model, which
will allow running multi-threaded applications at near hardware
speeds. Even though the application is multi-threaded, the KvmCPU
model uses one event queue, therefore, only one hardware thread
will be used, through KVM, to simulate multiple application threads.

Change-Id: I2b2a7b1edb1c56eeb9c4fa0553cd236029cd53f8
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18268
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@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>

mem: Move bind() and unbind() into the Port class.

These are now pure virtual methods which more specialized port
subclasses will need to implement. The SlavePort class implements them
by ignoring them and then providing parallel functions for the
MasterPort to call. The MasterPort's methods do basically what they
did before, except now bind() uses dynamic cast to check if its peer
is of the appropriate type and also to convert it into that type before
connecting to it.

Change-Id: I0948799bc954acaebf371e6b6612cee1d3023bc4
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17038
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
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>

mem: Move the Port base class into sim.

The Port class is going to be officially used for more than just memory
system connections.

Change-Id: I493e721f99051865c5f0c06946a2303ff723c2af
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17036
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

sim: Add size to array unserialization error message

Add both acquired and expected size information to array
unserialization error message.

Change-Id: Ic0a493c5a7860066eb992e9e91e7a4746b197579
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/16542
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

sim: Add a mechanism to exit the simulation loop immediately.

There are some cases, specifically when running systemc, that it's
necessary to exit the simulation loop immediately rather than finishing
running events scheduled for the current Tick. When running under
sc_main, sc_stop and sc_pause return control to sc_main which can
happen immediately. When running without sc_main, control needs to
return to the python config script which needs to happen through a
global exit event.

Since sc_pause and sc_stop are supposed to stop simulation without
necessarily letting all the events at the current time run, we need
a way to schedule an exit event with a very high priority (rather than
a very low priority).

This change adds a new exitSimLoopNow function which does that, and
adds a new constructor to the GlobalSimLoopExitEvent which uses that
priority.

Also, a couple of cruft functions from the sim events are removed.

Change-Id: Icfbec17fb10f98084a75740acd839dbf4096fbb3
Reviewed-on: https://gem5-review.googlesource.com/c/16444
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

python: Don't assume SimObjects live in the global namespace

The importer in Python 3 doesn't like the way we import SimObjects
from the global namespace. Convert the existing SimObject declarations
to import from m5.objects. As a side-effect, this makes these files
consistent with configuration files.

Change-Id: I11153502b430822130722839e1fa767b82a027aa
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15981
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>

python: Fix native module initialisation on Python 3

The approach we currently use to register our native modules doesn't
work on Python 3. Convert the code to use the Python inittab instead
of the old ad-hoc method.

Change-Id: I961f8a33993c621473732faeaab955a882769a4b
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15979
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Gabe Black <gabeblack@google.com>

kern,sim: implement FUTEX_WAKE_OP

This patch implements FUTEX_WAKE_OP operation in the futex syscall.
Below is its description:

int futex(int *uaddr, int futex_op, int val,
const struct timespec *timeout,
int *uaddr2, int val3);

This operation was added to support some user-space use cases where more
than one futex must be handled at the same time. The most notable
example is the implementation of pthread_cond_signal(3), which requires
operations on two futexes, the one used to implement the mutex and the
one used in the implementation of the wait queue associated with the
condition variable. FUTEX_WAKE_OP allows such cases to be implemented
without leading to high rates of contention and context switching.

Reference: http://man7.org/linux/man-pages/man2/futex.2.html

Change-Id: I215f3c2a7bdc6374e5dfe06ee721c76933a10f2d
Reviewed-on: https://gem5-review.googlesource.com/c/9630
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

sim, kern: support FUTEX_CMP_REQUEUE

This patch supports FUTEX_CMP_REQUEUE operation. Below is its
description from Linux man page:

futex syscall: int futex(int *uaddr, int futex_op, int val,
const struct timespec *timeout,
int *uaddr2, int val3);

This operation first checks whether the location uaddr still contains
the value val3. If not, the operation fails with the error EAGAIN.
Otherwise, the operation wakes up a maximum of val waiters that are
waiting on the futex at uaddr. If there are more than val waiters, then
the remaining waiters are removed from the wait queue of the source
futex at uaddr and added to the wait queue of the target futex at
uaddr2. The val2 argument specifies an upper limit on the number of
waiters that are requeued to the futex at uaddr2.

Reference: http://man7.org/linux/man-pages/man2/futex.2.html

Change-Id: I6d2ebd19a935b656d19d8342f7ab450c0d2031f4
Reviewed-on: https://gem5-review.googlesource.com/c/9629
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

sim: handle the case when there're not enough HW thread contexts

In SE mode, since there's no OS scheduler, the number of active SW
threads is limited by the number of HW thread contexts. Previously, if
there is no spare HW thread context, the simulator just fails and stops.
Instead, this patch returns EAGAIN error code from a clone syscall if
there's no available HW thread context. Then it's up to the simulated
program to handle the error.

Linux man page reference:
http://man7.org/linux/man-pages/man2/clone.2.html
http://man7.org/linux/man-pages/man2/fork.2.html

Change-Id: Ib4e092433e49de4dde376c8cb81f7d3f7851cbc0
Reviewed-on: https://gem5-review.googlesource.com/c/9628
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

sim,cpu: make exit_group halt all threads in a group

When a thread calls exit_group, in addition to halting the thread
itself, it needs to halt all other threads in its group (i.e., threads
sharing the same thread group ID). This patch enables threads to do
that.

Change-Id: Ib2e158fb27cf98843f177a64a2d643b1bbc94d03
Reviewed-on: https://gem5-review.googlesource.com/c/9623
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

sim,kern: support FUTEX_WAIT_BITSET and FUTEX_WAKE_BITSET ops

This patch adds support for two operations in futex system call:
FUTEX_WAIT_BITSET and FUTEX_WAKE_BITSET. The two operations are used to
selectively wake up a certain thread waiting on a futex variable.

Basically each thread waiting on a futex variable is associated with a
bitset that is checked when another thread tries to wake up all threads
waiting on the futex variable.

Change-Id: I2300e53b144d8fae226423fa2efb0238c1d93ef9
Reviewed-on: https://gem5-review.googlesource.com/c/9621
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

cpu: fixed how O3 CPU executes an exit system call

When a thread executed an exit syscall in SE mode, the thread context
was removed immediately in the same cycle, which left inflight squash
operations and trap event incomplete. The problem happened when a new
thread was assigned to the CPU later. The new thread started with some
incomplete transactions of the previous thread (e.g., squashing). This
problem could cause incorrect execution flow for the new thread (i.e.,
pc was not reset properly at the exit point), deadlock (i.e., some
stage-to-stage signals were not reset) and incorrect rename map between
logical and physical registers.

This patch adds a new state called 'Halting' to the thread context and
defers removing thread context from a CPU until a trap event initiated
by an exit syscall execution is processed. This patch also makes sure
that the removal of a thread context happens after all inflight
transactions of the to-be-removed thread in the pipeline complete.

Change-Id: If7ef1462fb8864e22b45371ee7ae67e2a5ad38b8
Reviewed-on: https://gem5-review.googlesource.com/c/8184
Reviewed-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

arch-riscv: Enable support for riscv 32-bit in SE mode.

This patch splits up the riscv SE mode support for 32 and 64-bit.
A future patch will add support for decoding rv32 instructions.

Change-Id: Ia79ae19f753caf94dc7e5830a6630efb94b419d7
Signed-off-by: Austin Harris <austinharris@utexas.edu>
Reviewed-on: https://gem5-review.googlesource.com/c/15355
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Alec Roelke <alec.roelke@gmail.com>
Maintainer: Alec Roelke <alec.roelke@gmail.com>

sim: added missed macro definition on MacOS

A recent patch add the use of the macro:
CMSG_ALIGN
This macro is not very cross-platform, and needs to be
defined according to the platform.

This patch defines the missing macro on MacOS.

Change-Id: I582f69e652dc060b4532358141179ad6d37eafc7
Reviewed-on: https://gem5-review.googlesource.com/c/16102
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

sim: Prepare C++ side for Python 3

Python 3 uses wide strings instead of ordinary strings for many
APIs. Add the necessary conversions to comply with the new API.

Change-Id: I6f45c9c532537d50d54b542f34eb8fd8cb375874
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15977
Reviewed-by: Gabe Black <gabeblack@google.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>

arch,cpu: Add vector predicate registers

Latest-gen. vector/SIMD extensions, including the Arm Scalable Vector
Extension (SVE), introduce the notion of a predicate register file.
This changeset adds this feature across architectures and CPU models.

Change-Id: Iebcadbad89c0a582ff8b1b70de353305db603946
Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13715
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

sim-se add readv and modifies writev

Change-Id: I6cbce4389d5697da34058dc910306394e48c6582
Reviewed-on: https://gem5-review.googlesource.com/c/12117
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>

sim-se: add ability to get/set sock metadata

Add getsockopt, getsockname, setsockname, and getpeername
system calls.

Change-Id: Ifa1d9a95f15b4fb12859dbfd3c4bd248de2e3d32
Reviewed-on: https://gem5-review.googlesource.com/c/12116
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>

sim-se: add syscalls related to polling

Fix poll so that it will use the syscall retry capability
instead of causing a blocking call.

Add the accept and wait4 system calls.

Add polling to read to remove deadlocks that occur in the
event queue that are caused by blocking system calls.

Modify the write system call to return an error number in
case of error.

Change-Id: I0b4091a2e41e4187ebf69d63e0088f988f37d5da
Reviewed-on: https://gem5-review.googlesource.com/c/12115
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>

sim-se: add calls for network transmissions

Add recvfrom, sendto, recvmsg, and sendmsg system calls.

Change-Id: I2eb50ea7823c8af57d99b3b8d443d2099418c06c
Reviewed-on: https://gem5-review.googlesource.com/c/12114
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>

sim-se: add socket-based functionality

Add socket, socketpair, bind, list, connect and shutdown
system calls.

Change-Id: I635af3fca410f96fe28f8fe497e3d457a9dbc470
Reviewed-on: https://gem5-review.googlesource.com/c/12113
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>

base: Fix unitialized storage

The bitunion is not being initialized on constructor to avoid
performance overhead, and that generated a maybe-unitialized
error when a sub-class was being copied before assigned in
serialize's parseParam() in some compilers.

This patch adds zero-initialization to the problematic variable
to appease the compiler.

Change-Id: I90fa6aa356b3e14ec25e3294b17ed10f429a9a38
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/15635
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

cpu: dev: sim: gpu-compute: Banish some ISA specific register types.

These types are IntReg, FloatReg, FloatRegBits, and MiscReg. There are
some remaining types, specifically the vector registers and the CCReg.
I'm less familiar with these new types of registers, and so will look
at getting rid of them at some later time.

Change-Id: Ide8f76b15c531286f61427330053b44074b8ac9b
Reviewed-on: https://gem5-review.googlesource.com/c/13624
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

sim-se, arch-arm: Add support for getdents64

Change-Id: Ib27950144d4c9802ffb842db98aec9e433ccbfc5
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Cc: Giacomo Travaglini <giacomo.travaglini@arm.com>
Cc: Javier Setoain <javier.setoain@arm.com>
Cc: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15438
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

sim-se: Refactor clone to avoid most ifdefs

Some parts of clone are architecture dependent. In some cases, we are
able to use architecture-specific helper functions or register
aliases. However, there is still some architecture-specific that is
protected by ifdefs in the common clone implementation.

Move these architecture-specific bits to the architecture-specific OS
class instead to avoid these ifdefs and make the code a bit more
readable.

Change-Id: Ia0903d738d0ba890863bddfa77e3b717db7f45de
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Cc: Giacomo Travaglini <giacomo.travaglini@arm.com>
Cc: Javier Setoain <javier.setoain@arm.com>
Cc: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15435
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

sim-se: Correctly calculate next PC in clone

The clone syscall doesn't propagate all state in the PCState object
when calculating the return PC of a newly created process. Instead of
creating a new PCState object from the next PC address, copy the old
PC and advance it.

Change-Id: Ice53831920bcb5d198865169ed2cca8d06e37cfe
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Cc: Giacomo Travaglini <giacomo.travaglini@arm.com>
Cc: Javier Setoain <javier.setoain@arm.com>
Cc: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15417
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

sim-se: Use CONFIG_CLONE_BACKWARDS for Arm

Linxu on Arm users the CLONE_BACKWARDS argument order for the clone
syscall.

Change-Id: I48deb4f03140c9d4ef7a89e3e33813e76777f999
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Cc: Giacomo Travaglini <giacomo.travaglini@arm.com>
Cc: Javier Setoain <javier.setoain@arm.com>
Cc: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15416
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

arch-x86: Add sys/syscall.h to x86 process.cc/syscall_emul.cc

Change a66d12c guards the selection of getdents()
in x86's process.cc file with SYS_getdents, however
process.cc does not include the right header for
SYS_getdents, which leads to x86 choosing the
unimplemented call. This change adds sys/syscall.h to
address the problem.

This change also adds sys/syscall.hh to syscall_emu.cc,
which only includes syscall.hh and may not be supported on
all systems.

Change-Id: If1adcf41e9e455de5f2827ba98c542fdcacdc22e
Reviewed-on: https://gem5-review.googlesource.com/c/14775
Reviewed-by: Ciro Santilli <ciro.santilli@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

base, sim: Add missing destructors

Derived classes with virtual functions need to define a virtual
destructor or a protected destructor otherwise calling the base class
destructor has undefined behavior. This change adds a virtual
distructor in the base class.

Change-Id: I1c855aa56dff6585ff99b9147bdb4eb9729a0a53
Signed-off-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/14815
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

sim-se: only implement getdentsFunc on supported hosts

The implementation of the getdents syscall relies on SYS_getdents, which
is not available on all archs, because the getdents syscall has been
superseded by getdents64, and does not exist on newer archs such as
aarch64.

This leads the build to break on aarch64 hosts with error:

error: 'SYS_getdents' was not declared in this scope

Change-Id: I8701fb5b61c0418b14a9463ef135a391a7f7a9ba
Reviewed-on: https://gem5-review.googlesource.com/c/14596
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

sim: Deschedule existing events when destructing an event queue.

Other objects in the simulation may try to deschedule their events when
destructed, and if they're cleaned up after the event queue is then
they might try to deschedule events on an event queue that no longer
exists.

Change-Id: I9452ce52fba78297ce3dc4b3884289b5e2f2574d
Reviewed-on: https://gem5-review.googlesource.com/c/14400
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>

sim: Move BitUnion overloading to show/parseParams

This patch is moving template overloading for BitUnions into the
showParam, parseParams functions. Henceforth BitUnion types will use the
common param wrapper.
This patch implicitly implements (UN)SERIALIZE_CONTAINER for BitUnions.

Change-Id: I0e1faadb4afd4dc9de5dc5fca40041e349c9ba73
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13636
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

sim: Move paramIn/Out definition to header file

This patch is moving the definitions of paramIn/Out templates to
the header file. In this way we gain:

1) We don't have to do explicit instantiation anymore for user defined
types. This spares us from including data type header files into
serialize.cc

2) We can overload show/parseParam for BitUnions or any other type
that requires special handling when serializing. Just by overloading
the two templates we get all the containers' (list, vector, array..)
serialization for free

2) gtest: With the idea of adding unit tests for Serializable objects,
we can avoid importing serialize.cc and just redefine Serializable
methods in the test source, implementing a Serializable stub

Change-Id: I45a9bb87d5ef886a3668fd477005cd105f612e36
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13635
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.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>

syscall_emul: fix openat when directory does not end in "/"

Before this commit, the following code:

dir_fd = open(".", O_DIRECTORY);
file_fd = openat(dir_fd, "ble", O_CREAT, S_IRUSR | S_IWUSR);

would create a file called ".ble" in the current working directory,
instead of the correct "ble".

Change-Id: I1525a088d49744e29b760387afabef9f1ac98646
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13005
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

sim: Extend (UN)SERIALIZE_ARRAY to BitUnions

This patch is making it possible to use SERIALIZE_ARRAY and UNSERIALIZE
array for serializing arrays of BitUnions.

Change-Id: I682766b472585f70a89338f373fb94dff5db53c3
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/12924
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

syscall_emul: implement dir-related syscalls

Add getdents, rmdir, chdir, and mknod to SE mode for x86.

Change-Id: I387ea3066869e8999bc0064f74070f4e47c1e9a1
Reviewed-on: https://gem5-review.googlesource.com/12112
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>

syscall_emul: refactor FDEntry and children classes

Strips off superfluous inline specifiers in header file.

Changes return types and parameters that deal with strings
to include the const& specifiers.

Change-Id: I570b1801abb059b91216f0223458d00963b9ca1c
Reviewed-on: https://gem5-review.googlesource.com/12111
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

syscall_emul: style changes and FDArray refactor

Some members were defined as public when they should have been
privately declared so these were moved to the appropriate spot.

The operator[] had inline specified for for an in-class
definition which is redundant since inline definitions are
always implicitly inline.

Private members had the leading underscore applied to them to
denote that they're private (consistent with style guide).

Changed static const defined class variable into a constexpr
with brace-list initialization.

Change-Id: If3054416b57827d1542e9ebab428d67d0e767723
Reviewed-on: https://gem5-review.googlesource.com/12110
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

syscall_emul: expand AuxVector class

The AuxVector class is responsible for holding Process data.
The data that it holds is normally setup by an OS kernel in
the process address space. The purpose behind doing this is
to pass in information that the process will need for various
reasons. (Check out the enum in the header file for an idea of
what the AuxVector holds.)

The AuxVector struct was changed into a class and encapsulation
methods were added to protect access to the member variables.

The host ISA may have a different endianness than the simulated
ISA. Since data is passed between the process address space and
the simulator for auxiliary vectors, we need to worry about
maintaining endianness for the right context.

Change-Id: I32c5ac4b679559886e1efeb4b5483b92dfc94af9
Reviewed-on: https://gem5-review.googlesource.com/12109
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>

power: Add a clock_period variable to power expressions

Currently 'Clock period in ticks' stat is not accessible in power equations .
This patch adds a variable 'clock_period' to be referenced to get the Clock period in
ticks

Signed-off-by: Sherif Elhabbal <elhabbalsherif@gmail.com>
Change-Id: Icac6a2e2003ed75d1680180e53343b0203139d72
Reviewed-on: https://gem5-review.googlesource.com/12664
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

base: Correct a small typo in sim/core.(hh|cc).

The value GHz with a small z was spelled GHZ with a large z, which was
inconsistent with the other frequency-like values in that namespace.

Change-Id: I55dfc447a5811ae584e46769cd9cadd08bd1e716
Reviewed-on: https://gem5-review.googlesource.com/12572
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

sim: Add System method for MasterID lookup

A new method (lookupMasterId) has been added to the System. A client
should use it when querying the System for the MasterID of a particular
master. It changes from getMasterId since it is
not registering a new MasterID if the master is not found in the
master's list.

Change-Id: I701158d22e235085bba9ab91154fbb702cae1467
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/11969
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

syscall_emul: adding symlink system call

Change-Id: Iebda05c130b4d2ee8434cad1e703933bfda486c8
Reviewed-on: https://gem5-review.googlesource.com/11490
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

syscall_emul: adding link system call

Change-Id: If8922c2233bbe1f6fce35f64d1a44b91d2cfeed2
Reviewed-on: https://gem5-review.googlesource.com/11489
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

dev: Exit correctly in dist-gem5 for SE mode

Do not allow the exit() syscall to terminate gem5 when running in dist-gem5
mode. The exit must be coordinated by the distributed interface instead.

Change-Id: I57f47610b59fe9e18ba3a1667fb5e45cecac1a81
Reviewed-on: https://gem5-review.googlesource.com/10461
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Mohammad Alian <m.alian1369@gmail.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

style: fix amd license and style issues

Change-Id: I26136fb49f743c4a597f8021cfd27f78897267b5
Reviewed-on: https://gem5-review.googlesource.com/10463
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>

sim: Remove trailing dot when assigning a master's name

This patch fixes the master's name allocation in the system. The error
was occurring when a submaster was not specified in getMasterId: a
trailing separation dot was still added to the master's name.

Change-Id: I0e67900f6fdd36a61900453b55219fc7007d1b05
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/10301
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

sim,cpu,mem,arch: Introduced MasterInfo data structure

With this patch a gem5 System will store more info about its Masters.
While it was previously keeping track of the Master name and Master ID
only, it is now adding a per-Master pointer to the SimObject related to
the Master.
This will make it possible for a client to query a System for a Master
using either the master's name or the master's pointer.

Change-Id: I8b97d328a65cd06f329e2cdd3679451c17d2b8f6
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/9781
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>

docs: Fix power model doxygen

Change-Id: I0a9a30bc4a89411e0f1dd897f0d1f05f20790b50
Signed-off-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-on: https://gem5-review.googlesource.com/9981
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>

sim-se: Fix fallthrough in prlimit

Change-Id: Ieec4651000b3b4de05ba5ba11fdfa5392a5477e7
Signed-off-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-on: https://gem5-review.googlesource.com/8904
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

sim, power: Temperature used for power calculations

The temperature used for the power calculations was fixed at 0
degrees, unless a thermal model was setup. This commit allows
the user to set the temperature that needs to be used by the
power calculation during gem5 configuration. This value will be
overwritten if there are thermal models present.

Change-Id: I7ca8fa6766bdcba9d362c12fc75d1e1f74385f35
Reviewed-by: Sascha Bischoff <sascha.bischoff@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/8602
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

sim: Added model type to power model

Static, dynamic or all to differentiate between types of power models
so for example static models will not be asked for a dynamic power

Change-Id: I3a0385821f7c671aedddaebeb038c677367faa81
Reviewed-by: Sascha Bischoff <sascha.bischoff@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/8601
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

sim: Add gtoh/htog helpers that take an explicit endianness

Add helper functions to swap between guest byte order and host byte
order that take a guest endianness as a parameter. These functions are
called htog and htog to be consistent with the helper functions that
extract guest byte order from a compile time constant.

Change-Id: Ie6be7dfd3b7a58ad6bfb57b25be5f85b5f425929
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/8201
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

sim: Remove _numContexts member in System class

A System object has a _numContexts member variable which represent the
number of ThreadContext registered in the System. Since this has to
match the size of the ThreadContext vector, this patch removes the
manually cached size. This was usually used as a for-loop index, whereas
we want to enforce the use of range-based loops whenever possible.

Change-Id: I1ba317c0393bcc9c1aeebbb1fc22d7b2bc2cf90c
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/8062
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.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>

tarch, mem: Abstract the data stored in the SE page tables.

Rather than store the actual TLB entry that corresponds to a mapping,
we can just store some abstracted information (address, a few flags)
and then let the caller turn that into the appropriate entry. There
could potentially be some small amount of overhead from creating
entries vs. storing them and just installing them, but it's likely
pretty minimal since that only happens on a TLB miss (ideally rare),
and, if it is problematic, there could be some preallocated TLB
entries which are just minimally filled in as necessary.

This has the nice effect of finally making the page tables ISA
agnostic.

Change-Id: I11e630f60682f0a0029b0683eb8ff0135fbd4317
Reviewed-on: https://gem5-review.googlesource.com/7350
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

x86, mem: Rewrite the multilevel page table class.

The new version extracts all the x86 specific aspects of the class,
and builds the interface around a variable collection of template
arguments which are classes that represent the different levels of the
page table. The multilevel page table class is now much more ISA
independent.

Change-Id: Id42e168a78d0e70f80ab2438480cb6e00a3aa636
Reviewed-on: https://gem5-review.googlesource.com/7347
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>

sim: Use the new BitUnion templates in serialize.hh.

serialize.hh should not reference internal implementation details in
the underlying BitUnion types.

Change-Id: I1ce29243db63801b7788f037fdc54811bdab889c
Reviewed-on: https://gem5-review.googlesource.com/7203
Maintainer: Gabe Black <gabeblack@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

base: Rework bitunions so they can be more flexible.

They are now oriented around a class which makes it easy to provide
custom setter/getter functions which let you set or read bits in an
arbitrary way.

Future additions may add the ability to add custom bitfield methods,
and index-able bitfields.

Change-Id: Ibd6d4d9e49107490f6dad30a4379a8c93bda9333
Reviewed-on: https://gem5-review.googlesource.com/7201
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>

sim, arch, base: Refactor the base remote GDB class.

Fold the GDBListener class into the main BaseRemoteGDB class, move
around a bunch of functions, convert a lot of internal functions to
be private, move some functions into the .cc, make some functions
non-virtual which didn't really need to be overridden.

Change-Id: Id0832b730b0fdfb2eababa5067e72c66de1c147d
Reviewed-on: https://gem5-review.googlesource.com/7422
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

arch, mem, sim: Consolidate and rename the SE mode page table classes.

Now that Nothing inherits from PageTableBase directly, it can be
merged into FuncPageTable. This change also takes the opportunity to
rename the combined class to EmulationPageTable which lets you know
that it's specifically for SE mode.

Also remove the page table entry cache since it doesn't seem to
actually improve performance. The TLBs likely absorb the majority of
the locality, essentially acting like a cache like they would in real
hardware.

Change-Id: If1bcb91aed08686603bf7bee37298c0eee826e13
Reviewed-on: https://gem5-review.googlesource.com/7342
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>

sim: Simplify registerThreadContext a little bit.

The code in this function was a little convoluted. This change attempts
to simplify it a little bit to make it easier to read.

Change-Id: I1ae557b9fede47fa89a9ea550bd0af8ad242449f
Reviewed-on: https://gem5-review.googlesource.com/7421
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch,mem: Move page table construction into the arch classes.

This gets rid of an awkward NoArchPageTable class, and also gives the
arch a place to inject ISA specific parameters (specifically page size)
without having to have TheISA:: in the generic version of these types.

Change-Id: I1412f303460d5c43dafdb9b3cd07af81c908a441
Reviewed-on: https://gem5-review.googlesource.com/6981
Reviewed-by: Alexandru Duțu <alexandru.dutu@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>

arch-riscv,sim: Support clone syscall in RISC-V

(1) This patch sets a correct order of clone syscall's arguments for
RISC-V. Linux kernel 4.15 uses CLONE_BACKWARDS flag by default for
RISC-V. The flag in the Linux kernel defines the list of clone syscall's
arguments in the following order:

clone_flags (flags)
newsp (newStack)
parent_tidptr (ptidPtr)
tls (tlsPtr)
child_tidptr (ctidPtr)

Code reference:
https://github.com/riscv/riscv-linux/blob/master/kernel/fork.c
https://github.com/riscv/riscv-linux/blob/master/arch/riscv/Kconfig

(2) This patch copies a parent thread's register values to its child
thread in clone syscall.

Change-Id: I2eb1c8e80990861080ce7153503ed784fb2c7bdf
Reviewed-on: https://gem5-review.googlesource.com/6904
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-by: Alec Roelke <ar4jc@virginia.edu>

sim: Fix a bug in prlimit syscall in SE mode

The old_limit pointer is supposed to be the 4th argument (index 3) of
the prlimit syscall. This patch sets old_limit pointer to the correct
argument.

Change-Id: I97808f7234cd2622cb3eb2f1e0beb7fc8cf492c1
Reviewed-on: https://gem5-review.googlesource.com/6903
Reviewed-by: Alec Roelke <ar4jc@virginia.edu>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

misc: Updates for gcc7.2 for x86

GCC 7.2 is much stricter than previous GCC versions. The following changes
are needed:

* There is now a warning if there is an implicit fallthrough between two
case statments. C++17 adds the [[fallthrough]]; declaration. However,
to support non C++17 standards (i.e., C++11), we use M5_FALLTHROUGH.
M5_FALLTHROUGH checks for [[fallthrough]] compliant C++17 compiler and
if that doesn't exist, it defaults to nothing (no older compilers
generate warnings).
* The above resulted in a couple of bugs that were found. This is noted
in the review request on gerrit.
* throw() for dynamic exception specification is deprecated
* There were a couple of new uninitialized variable warnings
* Can no longer perform bitwise operations on a bool.
* Must now include <functional> for std::function
* Compiler bug for void* lambda. Changed to auto as work around. See
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82878

Change-Id: I5d4c782a4e133fa4cdb119e35d9aff68c6e2958e
Signed-off-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-on: https://gem5-review.googlesource.com/5802
Reviewed-by: Gabe Black <gabeblack@google.com>

arm,sparc,x86,base,cpu,sim: Replace the Twin(32|64)_t types with.

Replace them with std::array<>s.

Change-Id: I76624c87a1cd9b21c386a96147a18de92b8a8a34
Reviewed-on: https://gem5-review.googlesource.com/6602
Maintainer: Gabe Black <gabeblack@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

base: Add endianness conversion functions for std::array types.

These swap the endianness of each element within the array
individually.

They probably obsolute the Twin(32|64)_t types which I believe were
used for SPARC.

Change-Id: Ic389eb24bdcdc0081068b0c5a37abdf416f6c924
Reviewed-on: https://gem5-review.googlesource.com/6581
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
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>

sim-se: Add default to SyscallDesc constructor

This patch adds a default value of unimplementedFunc to SyscallDesc's
constructor's second argument, which makes adding system call
placeholders to SE mode cleaner.

Change-Id: I3e7efb3a887cc52d16d2095d3dd2e2a96fb882fb
Reviewed-on: https://gem5-review.googlesource.com/5501
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

sim: Fix need to save address space info during serialization.

This fixes a fatal already mapped error in
FuncPageTable::allocate that occurs in some cases
when restoring from a checkpoint.

Change-Id: Ib726a69358118626663e42b7f14889b0d3a98de0
Reported-by: Ruohuang Zheng <zhengruohuang@gmail.com>
Signed-off-by: Austin Harris <austinharris@utexas.edu>
Reviewed-on: https://gem5-review.googlesource.com/5901
Reviewed-by: Gabe Black <gabeblack@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

sim: Implement load_addr_mask auto-calculation

Recent Linux kernels for AArch64 have changed their start addresses
but we still want to relocate the kernel to 0x80080000 which
required hacking the load_addr_mask in Realview.py to be 0x7ffffff
from 0xfffffff to mask off the proper number of MSBs to load the
kernel in the desired location. To avoid having to make this change
in the future again, we auto-calculate the load_addr_mask if it is
specified as 0x0 in the System sim-object to find the most restrictive
address mask instead of having the configuration specify it. If the
configuration does specify the address mask, we use it instead of
auto-calculating.

Change-Id: I18aabb5d09945c6e3e3819c9c8036ea24b6c35cf
Signed-off-by: Geoffrey Blake <Geoffrey.Blake@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2323
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

sim: ScopedMigration does nothing if both eqs are the same

Added a check to avoid unlocking/locking the same event queue. Also,
added an optional parameter to enable the migration to be skipped. This
can be useful to disable the synchronization for certain runtime
conditions.

Change-Id: I4b03b3ffff4f9503153cd41dd8aa78705bf16cc4
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5730
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

pwr: Enable multiple power models per component

This patch allows the user to specify more than one
power model for any given Clocked Object. This is
useful and some times necessary to properly model
components that have multiple power sources (or
subcomponents) but gem5 doesn't model them.

The ideal solution would be to have a DictParam
to replace the VectorParam so each model can have
a name and can be identified in the stats file.

Change-Id: I4080a7054a16b56069c44750a7a9ce4e674cdf9d
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5733
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

sim: Clocked object debug message updated for clarity

Change-Id: I5bbf36ef21ac14d9edf68ec6766d33f88e84d308
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5729
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

sim: Add an option to load additional kernel objects

There are cases where it is desirable to load a kernel and a set of
additional objects. This can, for example, be useful for testing where
the bootstrap code can be loaded from one object (the kernel) and the
test proper from another.

This changeset adds this functionality by adding a kernel_extras
vector parameter to the System class. Object files in this vector are
loaded in order after the kernel when running in full system mode.

Change-Id: I06f57c6a65a17b02eb4267bed0aa829f21bcfa3b
Reviewed-on: https://gem5-review.googlesource.com/5703
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

sim-se: Add prlimit system call

Some ISAs (namely RISC-V) implement getrlimit and setrlimit using
prlimit. This patch adds an implementation for the prlimit system call.
Normally prlimit is supposed to provide the functionality of both
getrlimit and setrlimit, but because gem5 does not support setrlimit
this implementation of prlimit will simply display a warning and return
a failure code if the setrlimit mode is used. The same thing will happen
if a pid other than 0 is passed to it.

Change-Id: I653af2d5a60e716f4d6286196be7600409efcef8
Reviewed-on: https://gem5-review.googlesource.com/5321
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

sim-se: Fix mremap for downward growing mmap regions

mremapFunc(...) did not respect Process::mmapGrowsDown(). This resulted
in an attempt to remap into an already allocated region and a panic in
FuncPageTable::allocate(...). This behavior can be observed in
435.gromacs.

Change-Id: Ib3ad33816126c76506d69679bdcefa7a98ef69f9
Reviewed-on: https://gem5-review.googlesource.com/4700
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

sim: make compile on FreeBSD prior to 11

FreeBSD before the early 11 development is expecting a char *
for stack.ss_sp rather than the standards compliant void *.
Catch that case and allow gem5 to compile on old FreeBSD versions.

Change-Id: Ic0ae560b52bfe5b3905ae87df791d349e053ec97
Reviewed-on: https://gem5-review.googlesource.com/4660
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

mem: Record the request master ID in the PacketInfo structure.

That can be recorded in a packet trace.

Change-Id: I3813ab4ea5aadeb40b355ff01f10e8ecab2bb790
Reviewed-on: https://soc-sim-internal-review.googlesource.com/3482
Reviewed-by: Rahul Thakur <rjthakur@google.com>
Reviewed-on: https://gem5-review.googlesource.com/4780
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>

sim: Stop using loadState in the Root SimObject.

The primary difference between using loadState and letting the default
implementation of loadState call unserialize is that whether or not that code
is called is dependent on that object being associated with a section in the
checkpoint file being unserialized. Since there's always a "root" object,
there should always be a section for it in the checkpoint and those should be
equivalent.

This removes one custom implementation of the loadState function.

Change-Id: Ia674ccc18e141f38746e22ccfddc21475b1a0731
Reviewed-on: https://gem5-review.googlesource.com/4740
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

sim: Use named constants for pseudo ops

Use named constants from a shared header instead of magic values when
handling pseudo ops.

Change-Id: If157060bbcd772ce7e8556482b44ca714f4319b1
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/4262
Reviewed-by: Gabe Black <gabeblack@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

sim: Prevent segfault in the wakeCpu m5op if id is invalid

Change-Id: I86229cedb206e10326cdee3f09a5c871e49c8d48
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/3965

sim, x86: Make clone a virtual function

This fixes the function call to clone in syscall_emul.hh where
the x86 version should be called before the base implementation
of clone.

Change-Id: Iccd2f680ff6e3a5536037d688a80ab3f236bbd98
Signed-off-by: Sean Wilson <spwilson2@wisc.edu>
Reviewed-on: https://gem5-review.googlesource.com/3902
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

sim, gdb: Refactor some Event subclasses into lambdas

Change-Id: If3e4329204f27eda96b50ec6ac279ebc6ef23d99
Signed-off-by: Sean Wilson <spwilson2@wisc.edu>
Reviewed-on: https://gem5-review.googlesource.com/3921
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

cpu, sim: Add param to force CPUs to wait for GDB

By setting the BaseCPU parameter wait_for_dbg_connection, the GDB
server blocks during initialisation waiting for the remote debugger to
connect before starting the simulated CPU.

Change-Id: I4d62c68ce9adf69344bccbb44f66e30b33715a1c
[ Update info message to include remote GDB port, rename param. ]
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/3963
Reviewed-by: Gabe Black <gabeblack@google.com>
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>

sim: Fix clashing stat names in TickedObject and Ticked

Change tickCycles numCycles stat name to totalTickCycles os as not to
clash with the name of the tickCycles stat of the same class.
Declared the params passed to the TickedObject constructer as const.
Call ClockedObject::regStats() from the TickedObject::regStats to
ensure the correct initialization of the base class (ClockedObject)
stats

Change-Id: I6cf5bbe10fa27f2ad0e31d9f70ec3be47fe41455
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/3964
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

cpu: Added interface for vector reg file

This patch adds some more functionality to the cpu model and the arch to
interface with the vector register file.

This change consists mainly of augmenting ThreadContexts and ExecContexts
with calls to get/set full vectors, underlying microarchitectural elements
or lanes. Those are meant to interface with the vector register file. All
classes that implement this interface also get an appropriate implementation.

This requires implementing the vector register file for the different
models using the VecRegContainer class.

This change set also updates the Result abstraction to contemplate the
possibility of having a vector as result.

The changes also affect how the remote_gdb connection works.

There are some (nasty) side effects, such as the need to define dummy
numPhysVecRegs parameter values for architectures that do not implement
vector extensions.

Nathanael Premillieu's work with an increasing number of fixes and
improvements of mine.

Change-Id: Iee65f4e8b03abfe1e94e6940a51b68d0977fd5bb
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
[ Fix RISCV build issues and CC reg free list initialisation ]
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2705

kvm: move Kvm check from ARM Kvm GIC to System

The check was nearly completely generic anyway,
with the exception of the Kvm CPU type.

This will make it easier for other parts of the
codebase to do similar checks.

Change-Id: Ibfdd3d65e9e6cc3041b53b73adfabee1999283da
Reviewed-on: https://gem5-review.googlesource.com/3540
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

sim: Updated ClockedObject power state warning

To prevent this warning from printing for *every* simulation, this patch
adds a check to only print the warning if we are not at the beginning of
simulation.

Change-Id: I7f6154f0ca26bef6280f909f799aa1c7936b624a
Signed-off-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-on: https://gem5-review.googlesource.com/3840
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

sim, x86: Replace EventWrapper use with EventFunctionWrapper

Change-Id: Ie1df07b70776208fc3631a73d403024636fc05a9
Signed-off-by: Sean Wilson <spwilson2@wisc.edu>
Reviewed-on: https://gem5-review.googlesource.com/3749
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>

sim: Add generic EventFunctionWrapper

Add EventFunctionWrapper, an event wrapper which takes any callable
object to use as its callback. (This includes c++ lambdas, function
pointers, bound functions, and std::functions.)

Change-Id: Iab140df47bd0f7e4b3fe3b568f9dd122a43cee1c
Signed-off-by: Sean Wilson <spwilson2@wisc.edu>
Reviewed-on: https://gem5-review.googlesource.com/3743
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>

sim: Remove DelayFunction

`DelayFunction` is unused.

Change-Id: I28aa756054c9b121fe4cfa65c393366f26ccb128
Signed-off-by: Sean Wilson <spwilson2@wisc.edu>
Reviewed-on: https://gem5-review.googlesource.com/3741
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

x86: sim: Make 32 bit x86 processes work again.

When the LiveProcess class was renamed to be just Process, the CL author
also changed the syscall function from a virtual function into a regular
one. Unfortunately, the I386Process class overrode the syscall function
to adjust the return address so that control would return to the right
place. Without that adjustment, 32 bit x86 process would segfault and die
immediately after their first system call.

This change reinstates the virtual specifier on the base syscall function,
and adds an override keyword on the I386Process's version so that it won't
be orphaned again in the future. It also fixes some small style issues the
style checker script complained about.

Change-Id: I0d1178ea0eda6676050c8fc043820a2bb4d99c0d
Reviewed-on: https://gem5-review.googlesource.com/3500
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

sim: Add hooks to implement event reference counting

We currently only support deleting an event if it is triggered and not
re-scheduled. This is fine for most native code. However, there are
cases where Python needs to count references to make sure that the
Python object stays live while the native object is live.

Generalise the mechanism used to implement by adding reference
counting hooks to the event base class:

* Event::acquire() / Event::acquireImpl()
* Event::release() / Event::releaseImpl()

These calls can be used to implement both reference counting and the
existing AutoDelete functionality. The default implementation in Event
maintains backwards compatibility with the existing AutoDelete feature
by ignoring acquireImpl() and deleting the event on releaseImpl() if
it isn't scheduled anymore.

Since AutoDelete functionality is no longer the only way events can be
managed, this change introduces the new Managed flag. This flag
activates automatic memory management. The acquireImpl()/releaseImpl()
methods are only called from acquire()/release() it is set. To
maintain backwards compatibility, AutoDelete is used as an alias for
Managed.

Change-Id: I5637984c906a9d44c22780712cf1c521b8297149
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/3221
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

base, sim, arch: Fix clang 5.0 warnings

Compiling gem5 with recent version of clang (4 and 5) triggers
warnings that are treated as errors:

* Global templatized static functions result in a warning if they
are not used. These should either be declared as static inline or
without the static identifier to avoid the warning.

* Some templatized classes contain static variables. The
instantiated versions of these variables / templates need to be
explicitly declared to avoid a compiler warning.

Change-Id: Ie8261144836e94ebab7ea04ccccb90927672c257
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/3420
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

syscall_emul: Fix undefined macro behavior

Clang's UBSAN implementation complains about macros that expand to
expressions that contain 'defined'. Explicitly set the various feature
macros to 1 or 0 to avoid this issue.

Change-Id: Iba239dacfe526c43ab9c5da5183a350fc4fdc57d
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/3241

syscall_emul: Argument retrieval bug fix

This commit fixes a stack-buffer underflow
by fixing the way the array is indexed.

Change-Id: I44400e2b99a2f8e1f48f673cd110b9dcd6480a72
Reviewed-on: https://gem5-review.googlesource.com/3040
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

base, sim, dev: Remove SWIG

Remove SWIG guards and SWIG-specific C++ code.

Change-Id: Icaad6720513b6f48153727ef3f70e0dba0df4bee
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/2921
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>

power: Allow global stats in power equations

Allow global stats such as sim_seconds in power equations to make it
possible to convert from event stats to rate stats.

Change-Id: I429abe0ffadc0dbd162eb39e0897143be472ef65
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2720
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

power: Clarify the unit used for the power equations (W)

Change-Id: Iab5070fc9b666fcb5b49b0e2b99a4a1605b3b721
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>

power: Add a voltage variable to power expressions

There is currently no good way of extracting the current operating
voltage in MathExprPowerModels. This change adds a magic variable,
'voltage', that can be referenced from such expressions to get the
current operating voltage.

Change-Id: Ice3c9a4a221921a542de5da52f83f3f88862d246
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Sascha Bischoff <sascha.bischoff@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2662
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

power: Add error checking to MathExprPowerModel

MathExprPower model currently doesn't print any useful error messages
if an expression fails to evaluate. To add insult to injury, the model
only detects a failure when dumping stats and not at
initialization. This change adds a verification step in startup() that
ensures that all of the referenced stats actually exist.

Change-Id: I8f71c73341578d5882c8d93e482f5383fbda5f1d
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Sascha Bischoff <sascha.bischoff@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2661
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

sim: Handle cases where Drainable::resume() creates objects

There are cases where Drainable objects need to create new objects in
Drainable::resume(). In such cases, the local drain state will be
inherited from the DrainManager. We currently set the state to Running
as soon as we start resuming the simulator. This means that new
objects are created in the Running state rather than the Drained
state, which the resume code assumes. Depending on the traversal order
in DrainManager::resume(), this sometimes triggers a panic because the
object being resumed is in the wrong state.

This change introduces a new drain state, Resuming, that the
DrainManager enters as soon as it starts resuming the
simulator. Objects that are created while resuming are created in this
state. Such objects are then resumed in a subsequent pass over the
list of Drainable objects that need to be resumed. Once all objects
have been resumed, the simulator enters the Running state.

Change-Id: Ieee8645351ffbdec477e9cd2ff86fc795e459617
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2600
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Weiping Liao <weipingliao@google.com>

syscall-emul: Hotfix for FreeBSD/Mac builds

The clone system call added in 236719892 relies on header files
from Linux systems. Obviously, this prevents compilation for
anyone using FreeBSD or Mac to compile the simulator. This
changeset is meant as a temporary fix to allow builds on
non-Linux systems until a proper solution is found.

Change-Id: I404cc41c588ed193dd2c1ca0c1aea35b0786fe4e
Reviewed-on: https://gem5-review.googlesource.com/2420
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

syscall-emul: change NULL to nullptr in Process files

Change-Id: I9ff21092876593237f919e9f7fb7283bd865ba2e
Reviewed-on: https://gem5-review.googlesource.com/2421
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>

style: change NULL to nullptr in syscall files

Change-Id: I02719f3572f6665cace1eb5681f297dcde9e71ce
Reviewed-on: https://gem5-review.googlesource.com/2271
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Michael LeBeane <Michael.Lebeane@amd.com>
Reviewed-by: Tony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

syscall-emul: Rewrite system call exit code

The changeset does a major refactor on the exit, exit_group, and
futex system calls regarding exit functionality.

A FutexMap class and related structures are added into a new
file. This increases code clarity by encapsulating the futex
operations and the futex state into an object.

Several exit conditions were added to allow the simulator to end
processes under certain conditions. Also, the simulation only
exits now when all processes have finished executing.

Change-Id: I1ee244caa9b5586fe7375e5b9b50fd3959b9655e
Reviewed-on: https://gem5-review.googlesource.com/2269
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

syscall-emul: Add the tgkill system call

This changeset adds support to kill a thread group by calling
the tgkill system call. The functionality is needed in some
pthread applications.

Change-Id: I0413a3331be69b74dfab30de95384113ec4efb63
Reviewed-on: https://gem5-review.googlesource.com/2268
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Tony Gutierrez <anthony.gutierrez@amd.com>
Reviewed-by: Michael LeBeane <Michael.Lebeane@amd.com>

syscall-emul: Adds SE mode signal feature

This changeset adds a simple class definition and a member
in the System object to track signals sent between processes.
The implementation cannot support all signals that might be
sent between processes, but it can support some of the simple
use cases like SIGCHLD.

Change-Id: Id5f95aa60e7f49da1c5b5596fbfa26e729453ac7
Reviewed-on: https://gem5-review.googlesource.com/2267
Reviewed-by: Michael LeBeane <Michael.Lebeane@amd.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

syscall-emul: Add or extend dup, dup2, and pipe

This changeset extends the pipe system call to work with
architectures other than Alpha (and enables the syscall for
x86). For the dup system call, it sets the clone-on-exec
flag by default. For the dup2 system call, the changeset
adds an implementation (and enables it for x86).

Change-Id: I00ddb416744ee7dd61a5cd02c4c3d97f30543878
Reviewed-on: https://gem5-review.googlesource.com/2266
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Tony Gutierrez <anthony.gutierrez@amd.com>
Reviewed-by: Michael LeBeane <Michael.Lebeane@amd.com>

syscall-emul: Add functionality to open syscalls

This changeset adds refactors the existing open system call,
adds the openat variant (enabled for x86 builds), and adds
additional "special file" test cases for /proc/meminfo and
/etc/passwd.

Change-Id: I6f429db65bbf2a28ffa3fd12df518c2d0de49663
Reviewed-on: https://gem5-review.googlesource.com/2265
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Tony Gutierrez <anthony.gutierrez@amd.com>
Reviewed-by: Michael LeBeane <Michael.Lebeane@amd.com>

style: Correct some style issues

This changeset fixes line alignment issues, spacing, spelling,
etc. for files that are used during SE Mode.

Change-Id: Ie61b8d0eb4ebb5af554d72f1297808027833616e
Reviewed-on: https://gem5-review.googlesource.com/2264
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Tony Gutierrez <anthony.gutierrez@amd.com>
Reviewed-by: Michael LeBeane <Michael.Lebeane@amd.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Pierre-Yves Péneau <pierre-yves.peneau@lirmm.fr>

syscall-emul: Move memState into its own file

The Process class is full of implementation details and
structures related to SE Mode. This changeset factors out an
internal class from Process and moves it into a separate file.
The purpose behind doing this is to clean up the code and make
it a bit more modular.

Change-Id: Ic6941a1657751e8d51d5b6b1dcc04f1195884280
Reviewed-on: https://gem5-review.googlesource.com/2263
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

power: Avoid forward declarations that confuse wrappers

The Python wrappers get confused by the forward declarations in the
power framework. This changeset restructures the code slightly to
avoid the troublesome forward declarations.

Change-Id: Id8c93224f1988edb5fdf9d3abc6237f2f688c02d
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-by: Sascha Bischoff <sascha.bischoff@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2227
Reviewed-by: Pierre-Yves Péneau <pierre-yves.peneau@lirmm.fr>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

syscall-emul: Remove unused class and member

The WaitRec structure in the Process class is unnecessary. There
is a member declaration inside of the Process class, waitList,
that uses the WaitRec definition. However, waitList is unused so
they are both dead bits of code. This changeset removes both the
WaitRec struct and waitList member from Process.

Change-Id: Ia6ee7488b9f47fd0f0ae29c818fba6ea0710699c
Reviewed-on: https://gem5-review.googlesource.com/2262
Reviewed-by: Tony Gutierrez <anthony.gutierrez@amd.com>
Reviewed-by: Michael LeBeane <Michael.Lebeane@amd.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

syscall_emul: [PATCH 15/22] add clone/execve for threading and multiprocess simulations

Modifies the clone system call and adds execve system call. Requires allowing
processes to steal thread contexts from other processes in the same system
object and the ability to detach pieces of process state (such as MemState)
to allow dynamic sharing.

syscall_emul: [patch 14/22] adds identifier system calls

This changeset add fields to the process object and adds the following
three system calls: setpgid, gettid, getpid.

syscall_emul: [patch 13/22] add system call retry capability

This changeset adds functionality that allows system calls to retry without
affecting thread context state such as the program counter or register values
for the associated thread context (when system calls return with a retry
fault).

This functionality is needed to solve problems with blocking system calls
in multi-process or multi-threaded simulations where information is passed
between processes/threads. Blocking system calls can cause deadlock because
the simulator itself is single threaded. There is only a single thread
servicing the event queue which can cause deadlock if the thread hits a
blocking system call instruction.

To illustrate the problem, consider two processes using the producer/consumer
sharing model. The processes can use file descriptors and the read and write
calls to pass information to one another. If the consumer calls the blocking
read system call before the producer has produced anything, the call will
block the event queue (while executing the system call instruction) and
deadlock the simulation.

The solution implemented in this changeset is to recognize that the system
calls will block and then generate a special retry fault. The fault will
be sent back up through the function call chain until it is exposed to the
cpu model's pipeline where the fault becomes visible. The fault will trigger
the cpu model to replay the instruction at a future tick where the call has
a chance to succeed without actually going into a blocking state.

In subsequent patches, we recognize that a syscall will block by calling a
non-blocking poll (from inside the system call implementation) and checking
for events. When events show up during the poll, it signifies that the call
would not have blocked and the syscall is allowed to proceed (calling an
underlying host system call if necessary). If no events are returned from the
poll, we generate the fault and try the instruction for the thread context
at a distant tick. Note that retrying every tick is not efficient.

As an aside, the simulator has some multi-threading support for the event
queue, but it is not used by default and needs work. Even if the event queue
was completely multi-threaded, meaning that there is a hardware thread on
the host servicing a single simulator thread contexts with a 1:1 mapping
between them, it's still possible to run into deadlock due to the event queue
barriers on quantum boundaries. The solution of replaying at a later tick
is the simplest solution and solves the problem generally.

style: [patch 12/22] fix preliminary style issues for subsequent fault patch

This changeset add spaces in a few spots and removes an unnecessary comment.

syscall_emul: [patch 11/22] extend functionality of fcntl

This changeset adds the ability to set a close-on-exec flag for a given
file descriptor. It also reworks some of the logic surrounding setting and
retrieving flags from the file description.

sim: Ensure draining is deterministic

The traversal of drainable objects could potentially be
non-deterministic when using an unordered set containing object
pointers. To ensure that the iteration is deterministic, we switch to
a vector. Note that the lookup and traversal of the drainable objects
is not performance critical, so the change has no negative consequences.

syscall_emul: [patch 10/22] refactor fdentry and add fdarray class

Several large changes happen in this patch.

The FDEntry class is rewritten so that file descriptors now correspond to
types: 'File' which is normal file-backed file with the file open on the
host machine, 'Pipe' which is a pipe that has been opened on the host machine,
and 'Device' which does not have an open file on the host yet acts as a pseudo
device with which to issue ioctls. Other types which might be added in the
future are directory entries and sockets (off the top of my head).

The FDArray class was create to hold most of the file descriptor handling
that was stuffed into the Process class. It uses shared pointers and
the std::array type to hold the FDEntries mentioned above.

The changes to these two classes needed to be propagated out to the rest
of the code so there were quite a few changes for that. Also, comments were
added where I thought they were needed to help others and extend our
DOxygen coverage.

syscall_emul: [patch 9/22] remove unused global variable (num_processes)

syscall_emul: [patch 8/22] refactor process class

Moves aux_vector into its own .hh and .cc files just to get it out of the
already crowded Process files. Arguably, it could stay there, but it's
probably better just to move it and give it files.

The changeset looks ugly around the Process header file, but the goal here is
to move methods and members around so that they're not defined randomly
throughout the entire header file. I expect this is likely one of the reasons
why I several unused variables related to this class. So, the methods are
declared first followed by members. I've tried to aggregate them together
so that similar entries reside near one another.

There are other changes coming to this code so this is by no means the
final product.

syscall_emul: [patch 7/22] remove numCpus method

The numCpus method is misleading in that it's not really a measure of
how many CPUs might be executing a process, but how many thread contexts
are assigned to the process at any given point in time.

It's nice to highlight this distinction because thread contexts are never
reused in the same way that a CPU can be reused for multiple processes.
The reason that there is no reuse is that there is no CPU scheduler for SE.

The tru64 code intends to use this method and the accompanying contextIDs
field to support SMT and track the number of threads with some system calls.
With the up coming clone and exec patches, this paradigm must change. There
needs to be a 1:1 mapping between the thread contexts and processes so that
the process state between threads is allowed to vary when needed by Linux.
This should not break SMT for tru64 if the Process class is refactored so that
multiple Processes can share state between themselves. The following patches
will do the refactoring incrementally as features are added.

syscall_emul: [patch 6/22] remove unused fields from Process class

It looks like tru64 has some nxm* system calls, but the two fields that
are defined in the Process class are unused by any of the code. There doesn't
appear to be any reference in the tru64 code.

syscall_emul: [patch 5/22] remove LiveProcess class and use Process instead

The EIOProcess class was removed recently and it was the only other class
which derived from Process. Since every Process invocation is also a
LiveProcess invocation, it makes sense to simplify the organization by
combining the fields from LiveProcess into Process.

sim: fix out-of-bounds error in syscall_desc

sim, kvm: make KvmVM a System parameter

A KVM VM is typically a child of the System object already, but for
solving future issues with configuration graph resolution, the most
logical way to keep track of this object is for it to be an actual
parameter of the System object.

Change-Id: I965ded22203ff8667db9ca02de0042ff1c772220
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>

sim,kvm,arm: fix typos

Change-Id: Ifc65d42eebfd109c1c622c82c3c3b3e523819e85
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>

misc: Fix order of object construction in the CxxConfigManager

The CxxConfigManager schould create objects by traversing the object tree
starting from the root object. However, currently objects are created in
aplphabetical order, which only works if the root object alphabetically
comes before any system object (e.g. 'root' < 'system'. Otherwise (e.g.
'a_system' < 'root'), object construction may fail. The reason for this
behaviour is, that the call to findObject() in the sorting code also
constructs the object if it is not yet existent. Then findTraversalOrder()
calls findObject("root") and subseqeuently calls findObject() on all the
children, and so on. However, the call to findTraversalOrder() is
redundant, since all objects are already created in alphabetical order.
This patch simply removes the alphabetical ordering, leading to the objects
being created starting from 'root'.

Reviewed at http://reviews.gem5.org/r/3778/

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

sim: fix build breakage in process.cc after brandon@11801

Seeing build breakage after brandon@11801:

[ CXX] X86/sim/process.cc -> .o build/X86/sim/process.cc:137:64:
error: field '_pid' is uninitialized when used here
[-Werror,-Wuninitialized] static_cast<PageTableBase *>(new
ArchPageTable(name(), _pid, system)) : ^ build/X86/sim/process.cc:138:64:
error: field '_pid' is uninitialized when used here
[-Werror,-Wuninitialized] static_cast<PageTableBase *>(new
FuncPageTable(name(), _pid))), ^ 2 errors generated.

Testing Done: Compiles now on FreeBSD 10 with clang.

Reviewed at http://reviews.gem5.org/r/3804/

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

sim: Patch to fix the statfs build

See developers mailing list. Trying to unbreak statfs.

Testing Done:
Builds on FreeBSD now.

Reviewed at http://reviews.gem5.org/r/3803/

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>

syscall_emul: [patch 4/22] remove redundant M5_pid field from process

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.

syscall_emul: #ifdef new system calls to allow builds on OSX and BSD

syscall_emul: [patch 2/22] move SyscallDesc into its own .hh and .cc

The class was crammed into syscall_emul.hh which has tons of forward
declarations and template definitions. To clean it up a bit, moved the
class into separate files and commented the class with doxygen style
comments. Also, provided some encapsulation by adding some accessors and
a mutator.

The syscallreturn.hh file was renamed syscall_return.hh to make it consistent
with other similarly named files in the src/sim directory.

The DPRINTF_SYSCALL macro was moved into its own header file with the
include the Base and Verbose flags as well.

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