Add an accuracy and coverage stat for the prefetchers.
Accuracy is defined as the ratio of the number of prefetch
request that have been counted as useful over the number
of prefetch request issued.
Accuracy tells whether the prefetcher is producing useful
requests or not.
Coverage is defined as the ratio of of the number of prefetch
request that have been counted as useful over the number of
demand misses if there was no prefetch, which is counted as
the number of useful prefetch request plus the remaining
demand misses. Due to the way stats are defined in the cache,
I have to add a stat to count the number of remaining demand
misses directly in the prefetcher stat. Demand is defined
as being one of this request type: ReadReq, WriteReq,
WriteLineReq, ReadExReq, ReadCleanReq, ReadSharedReq.
Coverage tells what part of misses are covered by the prefetcher.
Change-Id: I3bb8838f87b42665fdd782889f6ba56ca2a802fc
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/47603
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Daniel Carvalho <odanrc@yahoo.com.br>
Tested-by: kokoro <noreply+kokoro@google.com>
Count how many time a prefetch is useful, meaning
a hit has happened on a prefetched cache block.
Another stat (pfUsefulButMiss) has been added to count
the special case where there is a hit on prefetched block
but it is counted as a miss because the block is not in
the requested coherency state.
Change-Id: I253216b9ac96d5f21139b710c489d6eb3fce7136
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/47602
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Daniel Carvalho <odanrc@yahoo.com.br>
Tested-by: kokoro <noreply+kokoro@google.com>
Add a non-standard extension to the RSP protocol: the "." command
requests a dump of the simulated page table.
The dump consists of concatenated records, one record per page table
entry. Each record contains the entry's "virtual" value written as
hex, followed by a colon (:), followed by the entry's "physical" value
written as hex, followed by a semicolon (;).
At the time of writing, one practical use of this feature (in
combination with the "shared_backstore" parameter) is extremely fast
Miranda-Ingalls simulation of JIT compilers.
Change-Id: I333ed11d4ce671251d0b93cddae3bbcea44ea4ca
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/47719
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
In C, to refer to a type without a struct or enum tag on the type, you
need to typedef it like this:
typedef struct
{
} Foo;
Foo foo;
In C++, this is unnecessary:
struct Foo
{
};
Foo foo;
Remove all of the first form in C++ files and replace them with the
second form.
Change-Id: I37cc0d63b2777466dc6cc51eb5a3201de2e2cf43
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/46199
Reviewed-by: Gabe Black <gabe.black@gmail.com>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Apply the gem5 namespace to the codebase.
Some anonymous namespaces could theoretically be removed,
but since this change's main goal was to keep conflicts
at a minimum, it was decided not to modify much the
general shape of the files.
A few missing comments of the form "// namespace X" that
occurred before the newly added "} // namespace gem5"
have been added for consistency.
std out should not be included in the gem5 namespace, so
they weren't.
ProtoMessage has not been included in the gem5 namespace,
since I'm not familiar with how proto works.
Regarding the SystemC files, although they belong to gem5,
they actually perform integration between gem5 and SystemC;
therefore, it deserved its own separate namespace.
Files that are automatically generated have been included
in the gem5 namespace.
The .isa files currently are limited to a single namespace.
This limitation should be later removed to make it easier
to accomodate a better API.
Regarding the files in util, gem5:: was prepended where
suitable. Notice that this patch was tested as much as
possible given that most of these were already not
previously compiling.
Change-Id: Ia53d404ec79c46edaa98f654e23bc3b0e179fe2d
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/46323
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Matthew Poremba <matthew.poremba@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Table policies (i.e., replacement, compression, etc) behave
differently depending on the workload, and it is often desired
to be able to selectively switch between them. In this case
the relevant metadata for all the policies must be added to
all of the entries being analyzed.
In order to avoid having to monitor all table entries, a few
of these entries are selected to be sampled and estimate
overall behavior. These sampled entries belong each to a
single policy. Then, based on the predominance of these
samples, the winning policy is applied to the other sets
(followers).
As of now, in order to avoid having to iterate over a vector,
there is a limited number of dueling instances, but it may be
easily extended, if needed.
Based on Set Dueling, proposed in "Adaptive Insertion Policies
for High Performance Caching".
Change-Id: I692a3e5e0ad98581d68167ad7e6b45ab2f4c7b10
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/37895
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
With this change, when using a DPRINTF statment on a class inheriting
from the Queue or QueueEntry class, the name at the start of the log
line will be meaningful.
Currently affected classes:
MSHRqueue
MSHR
MSHR::TargetList
WriteQueue
WriteQueueEntry
Change-Id: I4e5ac080fec572961f9f1d9f88429ed6e72d8994
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/47040
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Daniel Carvalho <odanrc@yahoo.com.br>
Tested-by: kokoro <noreply+kokoro@google.com>
Sub-groups should not contain empty names. To make sure
that is the case, generate tokens even if the string is
empty.
Before the name 'group1..group2' would generate 2 tokens:
'group1' and 'group2'. As such, validateStatName would
not be able to detect it was an invalid name. With this
change three tokens will be generated: 'group1', '',
and 'group2'. The empty string will then trigger the
item->empty() check, which will successfully inform that
such stat name is not valid.
SLICC was breaking this rule with one of its stats by
creating a sub-group (inTransLatHist) whose parent had
an empty name, so it has been fixed.
Change-Id: Ica5ca684911374d59a0a809636594d048d755deb
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/43590
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Device memories are used for PCI devices which have their own pools of
backing store memory such as amdgpu device. The check for an address
being in device memory previously did not handle multiple interleaved
memory devices with the same address range. Therefore, the device memory
check would fail if the interleaving masks did not match. This updates
the method to iterate through all device memories that handle the
RequestorID and returns true if any of the device memories contain the
packet address.
Change-Id: I9339d39c1cb54a5b9075c4a122c118fe61dc6fdb
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/46381
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The AMPM paper (https://www.jilp.org/vol13/v13paper3.pdf) defines
the bandwidth-delay calculation as :
Mbandwidth= (Nrequests/Tepoch)×Tlatency
In the code, Tepoch and Tlatency are in ticks (which is okay),
but Tepoch is converted from Cycles (256K) to Ticks using the
clockEdge(Cycle c) function, which is incorrect as it yields currentTick
+ c * clockPeriod() instead of just c * clockPeriod().
In other words, the divider keeps increasing as time advances.
This patch substitutes clockEdge() with cyclesToTicks() to keep
the epoch length (Tepoch) constant throughout simulation.
Change-Id: I69dee29892fa4b9eb8de8715fd72a535e122687f
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/46479
Reviewed-by: Nathanael Premillieu <nathanael.premillieu@huawei.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
According to the DPC paper : "If the best score is less
than or equal to a fixed value BADSCORE, we turn prefetchoff
during the next phase"
However, the current code will turn prefetch off if the best
*offset* of the learning phase is less than BADSCORE, which
is incorrect.
Change-Id: Ib5790fe1341f2dd6328ec3b018bc52012e376723
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/46259
Reviewed-by: Nathanael Premillieu <nathanael.premillieu@huawei.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
