The event in KVM x86 SE mode plays double duty, triggering a system call
or a page fault depending on where it's called from (the system call
handler vs page fault handler).
This means we can eliminate the page fault gem5 op and the
pseudo_inst.hh switching header file.
This change touches a lot of things, but there wasn't really a good
place to split it up which still made sense and was consistent and
functional.
Change-Id: Ic414829917bcbd421893aa6c89d78273e4926b78
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/34165
Reviewed-by: Gabe Black <gabe.black@gmail.com>
Reviewed-by: Alexandru Duțu <alexandru.dutu@amd.com>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This function is no longer used anywhere in gem5.
Small helper functions which had been put alongside vtophys on ARM and
RISCV were also moved into src/arch/arm/remote_gdb.cc and
src/arch/power/pagetable.hh, the only places they were used.
Change-Id: Iba72f6c4b797a35a785a5bb781d602c943541fa7
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/26234
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The new local access mechanism installs a callback in the request which
implements what the mmapped IPR was doing. That avoids having to have
stubs in ISAs that don't have mmapped IPRs, avoids having to encode
what to do to communicate from the TLB and the mmapped IPR functions,
and gets rid of another global ISA interface function and header files.
Jira Issue: https://gem5.atlassian.net/browse/GEM5-187
Change-Id: I772c2ae2ca3830a4486919ce9804560c0f2d596a
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/23188
Reviewed-by: Matthew Poremba <matthew.poremba@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
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>
Generating dependency/build product information in the isa parser breaks scons
idea of how a build is supposed to work. Arm twisting it into working forced
a lot of false dependencies which slowed down the build.
Change-Id: Iadee8c930fd7c80136d200d69870df7672a6b3ca
Reviewed-on: https://gem5-review.googlesource.com/5081
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>
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
Factor out the ISA ness of the switching header generating function. Also
turn it into a SCons builder which builds a single header, and a wrapping
method which uses the builder on a group of header files which all target
the same subdirectory.
Change-Id: I87705f97b6ebd9baebd4ebcfea19cc1218a64ad0
Reviewed-on: https://gem5-review.googlesource.com/2983
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
the GPUISA class is meant to encapsulate any ISA-specific behavior - special
register accesses, isa-specific WF/kernel state, etc. - in a generic enough
way so that it may be used in ISA-agnostic code.
gpu-compute: use the GPUISA object to advance the PC
the GPU model treats the PC as a pointer to individual instruction objects -
which are store in a contiguous array - and not a byte address to be fetched
from the real memory system. this is ok for HSAIL because all instructions
are considered by the model to be the same size.
in machine ISA, however, instructions may be 32b or 64b, and branches are
calculated by advancing the PC by the number of words (4 byte chunks) it
needs to advance in the real instruction stream. because of this there is
a mismatch between the PC we use to index into the instruction array, and
the actual byte address PC the ISA expects. here we move the PC advance
calculation to the ISA so that differences in the instrucion sizes may be
accounted for in generic way.
This adds a vector register type. The type is defined as a std::array of a
fixed number of uint64_ts. The isa_parser.py has been modified to parse vector
register operands and generate the required code. Different cpus have vector
register files now.
This patch adds methods in KvmCPU model to handle KVM exits caused by syscall
instructions and page faults. These types of exits will be encountered if
KvmCPU is run in SE mode.
We currently generate and compile one version of the ISA code per CPU
model. This is obviously wasting a lot of resources at compile
time. This changeset factors out the interface into a separate
ExecContext class, which also serves as documentation for the
interface between CPUs and the ISA code. While doing so, this
changeset also fixes up interface inconsistencies between the
different CPU models.
The main argument for using one set of ISA code per CPU model has
always been performance as this avoid indirect branches in the
generated code. However, this argument does not hold water. Booting
Linux on a simulated ARM system running in atomic mode
(opt/10.linux-boot/realview-simple-atomic) is actually 2% faster
(compiled using clang 3.4) after applying this patch. Additionally,
compilation time is decreased by 35%.
This patch encompasses several interrelated and interdependent changes
to the ISA generation step. The end goal is to reduce the size of the
generated compilation units for instruction execution and decoding so
that batch compilation can proceed with all CPUs active without
exhausting physical memory.
The ISA parser (src/arch/isa_parser.py) has been improved so that it can
accept 'split [output_type];' directives at the top level of the grammar
and 'split(output_type)' python calls within 'exec {{ ... }}' blocks.
This has the effect of "splitting" the files into smaller compilation
units. I use air-quotes around "splitting" because the files themselves
are not split, but preprocessing directives are inserted to have the same
effect.
Architecturally, the ISA parser has had some changes in how it works.
In general, it emits code sooner. It doesn't generate per-CPU files,
and instead defers to the C preprocessor to create the duplicate copies
for each CPU type. Likewise there are more files emitted and the C
preprocessor does more substitution that used to be done by the ISA parser.
Finally, the build system (SCons) needs to be able to cope with a
dynamic list of source files coming out of the ISA parser. The changes
to the SCons{cript,truct} files support this. In broad strokes, the
targets requested on the command line are hidden from SCons until all
the build dependencies are determined, otherwise it would try, realize
it can't reach the goal, and terminate in failure. Since build steps
(i.e. running the ISA parser) must be taken to determine the file list,
several new build stages have been inserted at the very start of the
build. First, the build dependencies from the ISA parser will be emitted
to arch/$ISA/generated/inc.d, which is then read by a new SCons builder
to finalize the dependencies. (Once inc.d exists, the ISA parser will not
need to be run to complete this step.) Once the dependencies are known,
the 'Environments' are made by the makeEnv() function. This function used
to be called before the build began but now happens during the build.
It is easy to see that this step is quite slow; this is a known issue
and it's important to realize that it was already slow, but there was
no obvious cause to attribute it to since nothing was displayed to the
terminal. Since new steps that used to be performed serially are now in a
potentially-parallel build phase, the pathname handling in the SCons scripts
has been tightened up to deal with chdir() race conditions. In general,
pathnames are computed earlier and more likely to be stored, passed around,
and processed as absolute paths rather than relative paths. In the end,
some of these issues had to be fixed by inserting serializing dependencies
in the build.
Minor note:
For the null ISA, we just provide a dummy inc.d so SCons is never
compelled to try to generate it. While it seems slightly wrong to have
anything in src/arch/*/generated (i.e. a non-generated 'generated' file),
it's by far the simplest solution.
These classes are always used together, and merging them will give the ISAs
more flexibility in how they cache things and manage the process.
--HG--
rename : src/arch/x86/predecoder_tables.cc => src/arch/x86/decoder_tables.cc
Enables the CheckerCPU to be selected at runtime with the --checker option
from the configs/example/fs.py and configs/example/se.py configuration
files. Also merges with the SE/FS changes.
Because there are no longer architecture independent but specialized functions
in arch/XXX/faults.hh, code that isn't using the faults from a particular ISA
no longer needs to be able to include them through the switching header file
arch/faults.hh. By removing that header file (arch/faults.hh), the potential
interface between ISA code and non ISA code is narrowed.
There was a change a while ago that refactored some scons stuff which got rid
of cpu_models.py but also accidentally got rid of the ISA parser as a source
for its target files. That meant that changes which affected the parser
wouldn't cause a rebuild unless they also changed one of the description
files. This change fixes that.
There may not be a formally correct spelling for the past tense of mmap, but
mmapped is the spelling Google doesn't try to autocorrect. This makes sense
because it mirrors the past tense of map->mapped and not the past tense of
cape->caped.
--HG--
rename : src/arch/alpha/mmaped_ipr.hh => src/arch/alpha/mmapped_ipr.hh
rename : src/arch/arm/mmaped_ipr.hh => src/arch/arm/mmapped_ipr.hh
rename : src/arch/mips/mmaped_ipr.hh => src/arch/mips/mmapped_ipr.hh
rename : src/arch/power/mmaped_ipr.hh => src/arch/power/mmapped_ipr.hh
rename : src/arch/sparc/mmaped_ipr.hh => src/arch/sparc/mmapped_ipr.hh
rename : src/arch/x86/mmaped_ipr.hh => src/arch/x86/mmapped_ipr.hh
I like the brevity of Ali's recent change, but the ambiguity of
sometimes showing the source and sometimes the target is a little
confusing. This patch makes scons typically list all sources and
all targets for each action, with the common path prefix factored
out for brevity. It's a little more verbose now but also more
informative.
Somehow Ali talked me into adding colors too, which is a whole
'nother story.
Edit AlphaISA to support the inorder model. Mostly alternate constructor functions and also a few skeleton multithreaded support functions
* * *
Remove namespace from header file. Causes compiler issues that are hard to find
* * *
Separate the TLB from the CPU and allow it to live in the TLBUnit resource. Give CPU accessor functions for access and also bind at construction time
* * *
Expose memory access size and flags through instruction object
(temporarily memAccSize and memFlags to get TLB stuff working.)
