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>

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>

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>

sparc: Get rid of some register type definitions.

These are IntReg, FloatReg, FloatRegBits, and MiscReg. These have been
supplanted by the global types RegVal and FloatRegVal.

Change-Id: I956abfc7b439b083403e1a0d01e0bb35020bde44
Reviewed-on: https://gem5-review.googlesource.com/c/13627
Maintainer: Gabe Black <gabeblack@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.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>

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 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.

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.

sim: revert 6709bbcf564d
The identifier SYS_getdents is not available on Mac OS X. Therefore, its use
results in compilation failure. It seems there is no straight forward way to
implement the system call getdents using readdir() or similar C functions.
Hence the commit 6709bbcf564d is being rolled back.

sim: implement getdents/getdents64 in user mode

Has been tested only for alpha.
Committed by: Nilay Vaish <nilay@cs.wisc.edu>

sysemul: bump all linux versions of for syscal emulation to 3.0.

New tool chains seem to be looking for kernel versions newer than what
this this was previously set to. Also take this opportunity to change
the hostname we report in uname to sim.gem5.org.

MEM: Add port proxies instead of non-structural ports

Port proxies are used to replace non-structural ports, and thus enable
all ports in the system to correspond to a structural entity. This has
the advantage of accessing memory through the normal memory subsystem
and thus allowing any constellation of distributed memories, address
maps, etc. Most accesses are done through the "system port" that is
used for loading binaries, debugging etc. For the entities that belong
to the CPU, e.g. threads and thread contexts, they wrap the CPU data
port in a port proxy.

The following replacements are made:
FunctionalPort > PortProxy
TranslatingPort > SETranslatingPortProxy
VirtualPort > FSTranslatingPortProxy

SPARC: Clean up some historical style issues.

Syscalls: Make system calls access arguments like a stack, not an array.

When accessing arguments for a syscall, the position of an argument depends on
the policies of the ISA, how much space preceding arguments took up, and the
"alignment" of the index for this particular argument into the number of
possible storate locations. This change adjusts getSyscallArg to take its
index parameter by reference instead of value and to adjust it to point to the
possible location of the next argument on the stack, basically just after the
current one. This way, the rules for the new argument can be applied locally
without knowing about other arguments since those have already been taken into
account implicitly.

All system calls have also been changed to reflect the new interface. In a
number of cases this made the implementation clearer since it encourages
arguments to be collected in one place in order and then used as necessary
later, as opposed to scattering them throughout the function or using them in
place in long expressions. It also discourages using getSyscallArg over and
over to retrieve the same value when a temporary would do the job.

Syscalls: Implement sysinfo() syscall.

Commit m5threads package.

This patch adds limited multithreading support in syscall-emulation
mode, by using the clone system call. The clone system call works
for Alpha, SPARC and x86, and multithreaded applications run
correctly in Alpha and SPARC.

SE mode: Make keeping track of the number of syscalls less hacky.

Processes: Make getting and setting system call arguments part of a process object.

sycalls: implement mremap() and add DATA flag for getrlimit(). mremap has been tested on Alpha, compiles for the rest but not tested. I don't see why it wouldn't work though.

syscalls: fix latent brk/obreak bug.
Bogus calls to ChunkGenerator with negative size were triggering
a new assertion that was added there.
Also did a little renaming and cleanup in the process.

syscalls: Add a bunch of missing system calls.
readlink, umask, truncate, ftruncate, mkdir, and getcwd.

Ignore "time" and "times" syscalls.

Add the rename syscall.

Split the syscall table, SPARC specific syscall implementations, and the 32 bit syscall table into it's own file. Corrected problems with the stat structure. These should be tested on 64 bit x86 and SPARC machines.