The current MESI_Two_Level protocol's L1 caches updates the MRU information twice per request on misses -- once when the request reaches Ruby and once when the miss is returned from another level of the memory hierarchy.
Although this approach does not cause any correctness bugs for replacement policies like LRU since this request is the LRU in both cases, it does not work correctly for other policies like SecondChance and LFU, where updating the information twice (for misses) causes them to devolve to LRU.
Note that this was not directly a problem with Ruby previously, because it only supported LRU-based policies that were unaffected by this. However, with the integration of 20879 Ruby now uses the same replacement policies as Classic (which has additional, non-LRU based replacement policies).
This patch resolves this problem by not updating the MRU information a second time for the misses. It has been tested and validated with the replacement policy tests.
Change-Id: I9e7e96a9d6c09f3d6b7daae7115ef091ac3bdc08
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/64371
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
In python, when you use -c it consumes all subsequent parameters and
appends them to argv. Now, gem5 and python behave the same with -c.
Python:
> python -c "import sys; print(sys.argv)" --hello -j
['-c', '--hello', '-j']
gem5:
> gem5.opt -c "import sys; print(sys.argv)" --hello -j
gem5 Simulator System. https://www.gem5.org
gem5 is copyrighted software; use the --copyright option for details.
gem5 version [DEVELOP-FOR-22.1]
gem5 compiled Oct 17 2022 15:47:46
gem5 started Oct 17 2022 15:53:45
gem5 executing on challenger, pid 4021103
command line: build/ALL/gem5.opt -c 'import sys; print(sys.argv)' --hello -j
['-c', '--hello', '-j']
Change-Id: I53e87712be9523e0583149235c9787c92618f884
Signed-off-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/63151
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
The conversion logic between gem5 register id and iris resouce id is
duplicated in read and write function. Some of them also doesn't handle
the invalid id correctly. This change wraps the logic, fixes them, and
improves the debug messages by printing the register names.
Change-Id: I093d05f5f06d804d5f01988c2a7ffa60244c5516
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/64651
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Gabe Black <gabeblack@google.com>
The current protoc_action generates declarations that impose the requirement
for .proto files to import from the BUILDDIR. This prevents .proto files to
import themselves relative to their own directory.
For example, if there are two files build/pkg/a.proto and build/pkg/b.proto,
and b.proto imports a.proto, it must do so as "import pkg/a.proto", as opposed
to "import a.proto"; otherwise, the generated declaration will give rise to a
compilation error.
This is a problem for EXTRAS where .proto files are gem5-independent, so
they cannot import from gem5's build directory. An example is
https://github.com/ARM-software/ATP-Engine
This commit changes the protoc_action so that declarations are generated
relative to the SOURCE directory. This enables .proto files to import
other .proto files within the same directory.
Note it is not possible to import other .proto files in different
directories, but support for it is not currently necessary.
More details on the proto path:
https://developers.google.com/protocol-buffers/docs/reference/cpp-generated#invocation
Related:
https://gem5-review.googlesource.com/c/public/gem5/+/55903
Change-Id: Ib3e67ae817f8ad0b6803c90d23469267eff16178
Signed-off-by: Adrián Herrera Arcila <adrian.herrera@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/64491
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
This debug flag is used to print spammy SDMA DPRINTFs, such as an SDMA
copy printing the data of large transfers 8 bytes per line at a time. For
those prints, the SDMAEngine flag will now only print the first and last
qword of the transfer and the new SDMAData flag is needed for verbose
data printing. This makes the SDMAEngine flag still useful for verifying
copies in applications with predictable data such as square.
Additionally, the memory allocation/deallocation done solely for a print
statement is removed in favor of casting the data to the printed type.
Change-Id: I18c1918ef9085cca4570f79881ee63d510ccc32f
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/64452
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Page directory entries (PDEs) can be interpreted as leaf node page
table entries (PTEs) if the "p" bit is set. This is used for flexible
page sizes in Vega. Currently there is only support for PDE level 0
entries which can be interpreted as 2MB pages. This changeset adds
support for PDE1 and PDE2 which can be used to represent 1GB and 512GB
pages. PDE1-as-PTE entries can be tested and were verified on
applications by allocating >2GB of data. PDE0 is untested due to being
too large for simulation, but the implementation is similar to PDE0
and PDE1.
Change-Id: I801cbb5ec79110d57d2db760cc689c2e5778f9bb
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/64451
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Clang Version 14 throws a warning "use of bitwise '&/|' with boolean
operands" for cases where bitwise operations are used where boolean
operations are intended.
This occurred in "WriteMast.hh", "data.isa", and "decode.cc" where
boolean values were being compared using the bitwise operands. While
bitwise operations are equivalent, they have been changed to boolean
operations in this patch to avoid the clang-14 warning.
Change-Id: Ic7583e13a325661712c75c8e1b234c4878832352
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/64172
Reviewed-by: Tom Rollet <tom.rollet@huawei.com>
Reviewed-by: Kunal Pai <kunpai@ucdavis.edu>
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
The `Addr line_addr` in "src/mem/snoop_filter.cc" variable was only
used in an assert, stripped when compiling gem5.fast.
Clang-13 throws a warning for this variable. This has been fixed by
merging the variable and associated logic into the assert statement.
The variables in inet.cc and Sequencer.cc were also causing an 'unused
variable' warning to be thrown due to variables that were only used in
assert statements. In these cases the logic could not be moved into the
assert statement and, as such, the `GEM5_VAR_USED` MACRO is used to
remove this warning.
Change-Id: I6511d0863608c38b79e4558c7dcf35a323fe8362
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/64171
Reviewed-by: Kunal Pai <kunpai@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
This change updates the default actions taken when the user doesn't
specify generators for the exit events in the simulator. Rather than
defining default generators, this change makes the generators more
generic and gives a new decorator to mark them as default.
This change then updates the default generators in the simulator and
only makes some of them issue a default warning. For exit events such as
EXIT, the default will no longer print a warning.
Change-Id: I5552f52392f3aea577034ed278a9ff9e8b5b0b01
Signed-off-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/64251
Reviewed-by: Zhantong Qiu <ztqiu@ucdavis.edu>
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
There are two initial scalar register fields that are not initialized in
the wavefront when a task is dispatch. This changeset adds the missing
DispatchId and PrivateSegSize fields. These fields are typically used
when an application is compiled with debug support and are typically not
used in the applications in gem5's test suite.
Change-Id: I5b5fa75e4badfd9ba7588e4cd485ebf75fd5d627
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/64191
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Adding a small python function that allows to display
messages directly in GDB from the python interpreter.
This function is inside the Workload SimObject
(The stub is not a SimObject).
ex:
system.workload.sendToGdb("message to display")
Change-Id: I46ddae079b10d298743e023f95bf15608f50e358
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/63531
Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu>
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
The remote protocol describes 2 type of stop respond packet.
S packets (which are the one that where used before) and T packets.
T packet support multiple fields to give more information about:
- thread/core which stopped
- registers values
- A stopReason string that are predefined value and that can
differentiate between different types of break that would
issue the same signal.
Change-Id: Id8ed7115898bf825dd14395f586c393d6f5aa2bc
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/63528
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
Add a try_getbyte function that feature a timeout. This function uses
select to detect update on the file descriptor used to communicate with
the remote.
It is used to implement getbyte and to clean the file
descriptor before sending a message with send.
Now getbyte and send can recover from certains error like interruption
by other signals (EINTR) or delays causing the remote server to send
error packet to the stub.
Change-Id: Ie06845ba59dee0ad831632d5bc2b15132c9d5450
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/63526
Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu>
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
This map was originally used for fast access to the GART table. It is no
longer needed as the table has been moved to the AMDGPUVM class. Along
with commit 12ec5f9172 which reads
functionally from device memory, this table is no longer needed and is
essentially a duplicate copy of device memory for anything written over
the PCI BAR.
This changeset removes the map entirely which will reduce the memory
footprint of simulations and potentially avoid stale copies of data
when reading over the PCI BAR.
Change-Id: I312ae38f869c6a65e50577b1c33dd055078aaf32
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/63951
Reviewed-by: Matt Sinclair <mattdsinclair.wisc@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
