Searched hist:2015 (Results 876 - 900 of 1505) sorted by relevance

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/gem5/tests/long/se/10.mcf/ref/x86/linux/simple-timing/
H A Dstats.txt11201:b1bd4afb6b16 Fri Nov 06 03:26:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> stats: Update stats to match cache changes
11138:a611a23c8cc2 Fri Sep 25 07:27:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> stats: Update stats to reflect snoop-filter changes
10892:bd37e25fb3b7 Fri Jul 03 10:15:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> stats: Update stats for cache, crossbar and DRAM changes

This update includes the changes to whole-line writes, the refinement
of Read to ReadClean and ReadShared, the introduction of CleanEvict
for snoop-filter tracking, and updates to the DRAM command scheduler
for bank-group-aware scheduling.

Needless to say, almost every regression is affected.
10827:7f5467f2f8b8 Tue May 05 03:22:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> stats: Update stats to reflect cache changes
10726:8a20e2a1562d Mon Mar 02 05:04:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> stats: Update stats to reflect cache and interconnect changes

This is a bulk update of stats to match the changes to cache timing,
interconnect timing, and a few minor changes to the o3 CPU.
/gem5/tests/long/se/20.parser/ref/x86/linux/simple-timing/
H A Dstats.txt11201:b1bd4afb6b16 Fri Nov 06 03:26:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> stats: Update stats to match cache changes
11138:a611a23c8cc2 Fri Sep 25 07:27:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> stats: Update stats to reflect snoop-filter changes
10892:bd37e25fb3b7 Fri Jul 03 10:15:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> stats: Update stats for cache, crossbar and DRAM changes

This update includes the changes to whole-line writes, the refinement
of Read to ReadClean and ReadShared, the introduction of CleanEvict
for snoop-filter tracking, and updates to the DRAM command scheduler
for bank-group-aware scheduling.

Needless to say, almost every regression is affected.
10827:7f5467f2f8b8 Tue May 05 03:22:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> stats: Update stats to reflect cache changes
10726:8a20e2a1562d Mon Mar 02 05:04:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> stats: Update stats to reflect cache and interconnect changes

This is a bulk update of stats to match the changes to cache timing,
interconnect timing, and a few minor changes to the o3 CPU.
/gem5/tests/long/se/60.bzip2/ref/x86/linux/simple-timing/
H A Dstats.txt11201:b1bd4afb6b16 Fri Nov 06 03:26:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> stats: Update stats to match cache changes
11138:a611a23c8cc2 Fri Sep 25 07:27:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> stats: Update stats to reflect snoop-filter changes
10892:bd37e25fb3b7 Fri Jul 03 10:15:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> stats: Update stats for cache, crossbar and DRAM changes

This update includes the changes to whole-line writes, the refinement
of Read to ReadClean and ReadShared, the introduction of CleanEvict
for snoop-filter tracking, and updates to the DRAM command scheduler
for bank-group-aware scheduling.

Needless to say, almost every regression is affected.
10827:7f5467f2f8b8 Tue May 05 03:22:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> stats: Update stats to reflect cache changes
10726:8a20e2a1562d Mon Mar 02 05:04:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> stats: Update stats to reflect cache and interconnect changes

This is a bulk update of stats to match the changes to cache timing,
interconnect timing, and a few minor changes to the o3 CPU.
/gem5/configs/common/
H A DCaches.py11199:929fd978ab4e Fri Nov 06 03:26:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Add an option to perform clean writebacks from caches

This patch adds the necessary commands and cache functionality to
allow clean writebacks. This functionality is crucial, especially when
having exclusive (victim) caches. For example, if read-only L1
instruction caches are not sending clean writebacks, there will never
be any spills from the L1 to the L2. At the moment the cache model
defaults to not sending clean writebacks, and this should possibly be
re-evaluated.

The implementation of clean writebacks relies on a new packet command
WritebackClean, which acts much like a Writeback (renamed
WritebackDirty), and also much like a CleanEvict. On eviction of a
clean block the cache either sends a clean evict, or a clean
writeback, and if any copies are still cached upstream the clean
evict/writeback is dropped. Similarly, if a clean evict/writeback
reaches a cache where there are outstanding MSHRs for the block, the
packet is dropped. In the typical case though, the clean writeback
allocates a block in the downstream cache, and marks it writable if
the evicted block was writable.

The patch changes the O3_ARM_v7a L1 cache configuration and the
default L1 caches in config/common/Caches.py
11053:62544e45c0f4 Fri Aug 21 07:03:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Add explicit Cache subclass and make BaseCache abstract

Open up for other subclasses to BaseCache and transition to using the
explicit Cache subclass.
10887:279efb97ec99 Fri Jul 03 10:14:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Remove redundant is_top_level cache parameter

This patch takes the final step in removing the is_top_level parameter
from the cache. With the recent changes to read requests and write
invalidations, the parameter is no longer needed, and consequently
removed.

This also means that asymmetric cache hierarchies are now fully
supported (and we are actually using them already with L1 caches, but
no table-walker caches, connected to a shared L2).
10884:c60acdbdd6ad Fri Jul 03 10:14:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Allow read-only caches and check compliance

This patch adds a parameter to the BaseCache to enable a read-only
cache, for example for the instruction cache, or table-walker cache
(not for x86). A number of checks are put in place in the code to
ensure a read-only cache does not end up with dirty data.

A follow-on patch adds suitable read requests to allow a read-only
cache to explicitly ask for clean data.
10820:e2a283400c43 Tue May 05 03:22:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> arch, cpu: Do not forward snoops to table walker

This patch simplifies the overall CPU by changing the TLB caches such
that they do not forward snoops to the table walker port(s). Note that
only ARM and X86 are affected.

There is no reason for the ports to snoop as they do not actually take
any action, and from a performance point of view we are better of not
snooping more than we have to.

Should it at a later point be required to snoop for a particular TLB
design it is easy enough to add it back.
H A DMemConfig.py11251:a15c86af004a Mon Dec 07 17:42:00 EST 2015 Radhika Jagtap <radhika.jagtap@ARM.com> config: Enable elastic trace capture and replay in se/fs

This patch adds changes to the configuration scripts to support elastic
tracing and replay.

The patch adds a command line option to enable elastic tracing in SE mode
and FS mode. When enabled the Elastic Trace cpu probe is attached to O3CPU
and a few O3 CPU parameters are tuned. The Elastic Trace probe writes out
both instruction fetch and data dependency traces. The patch also enables
configuring the TraceCPU to replay traces using the SE and FS script.

The replay run is designed to resume from checkpoint using atomic cpu to
restore state keeping it consistent with FS run flow. It then switches to
TraceCPU to replay the input traces.
11183:276ad9121192 Tue Nov 03 01:17:00 EST 2015 Erfan Azarkhish <erfan.azarkhish@unibo.it> mem: hmc: top level design

This patch enables modeling a complete Hybrid Memory Cube (HMC) device. It
highly reuses the existing components in gem5's general memory system with some
small modifications. This changeset requires additional patches to model a
complete HMC device.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
10993:4e27d8806403 Tue Aug 04 00:08:00 EDT 2015 Matthias Jung <jungma@eit.uni-kl.de> misc: Coupling gem5 with SystemC TLM2.0
Transaction Level Modeling (TLM2.0) is widely used in industry for creating
virtual platforms (IEEE 1666 SystemC). This patch contains a standard compliant
implementation of an external gem5 port, that enables the usage of gem5 as a
TLM initiator component in SystemC based virtual platforms. Both TLM coding
paradigms loosely timed (b_transport) and aproximately timed (nb_transport) are
supported.

Compared to the original patch a TLM memory manager was added. Furthermore, the
transaction object was removed and for each TLM payload a PacketPointer that
points to the original gem5 packet is added as an TLM extension. For event
handling single events are now created.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
10789:e94c22bd9ef1 Mon Apr 20 00:46:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> config: Remove memory aliases and rely on class name

Instead of maintaining two lists, rely entirely on the class
name. There is really no point in causing unecessary confusion.
10780:46070443051e Wed Apr 08 16:56:00 EDT 2015 Curtis Dunham <Curtis.Dunham@arm.com> config: Support full-system with SST's memory system

This patch adds an example configuration in ext/sst/tests/ that allows
an SST/gem5 instance to simulate a 4-core AArch64 system with SST's
memHierarchy components providing all the caches and memories.
10677:5935ab1ddd7a Tue Feb 03 14:25:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> config: Add XOR hashing to the DRAM channel interleaving

This patch uses the recently added XOR hashing capabilities for the
DRAM channel interleaving. This avoids channel biasing due to strided
access patterns.
10675:bb7cd7193edc Tue Feb 03 14:25:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> config: Adjust DRAM channel interleaving defaults

This patch changes the DRAM channel interleaving default behaviour to
be more representative. The default address mapping (RoRaBaCoCh) moves
the channel bits towards the least significant bits, and uses 128 byte
as the default channel interleaving granularity.

These defaults can be overridden if desired, but should serve as a
sensible starting point for most use-cases.
/gem5/src/arch/alpha/
H A Disa.hh11168:f98eb2da15a4 Mon Oct 12 04:07:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> misc: Remove redundant compiler-specific defines

This patch moves away from using M5_ATTR_OVERRIDE and the m5::hashmap
(and similar) abstractions, as these are no longer needed with gcc 4.7
and clang 3.1 as minimum compiler versions.
10935:acd48ddd725f Tue Jul 28 02:58:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> revert 5af8f40d8f2c
10934:5af8f40d8f2c Sun Jul 26 11:21:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> cpu: implements vector registers

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.
10905:a6ca6831e775 Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Refactor the serialization base class

Objects that are can be serialized are supposed to inherit from the
Serializable class. This class is meant to provide a unified API for
such objects. However, so far it has mainly been used by SimObjects
due to some fundamental design limitations. This changeset redesigns
to the serialization interface to make it more generic and hide the
underlying checkpoint storage. Specifically:

* Add a set of APIs to serialize into a subsection of the current
object. Previously, objects that needed this functionality would
use ad-hoc solutions using nameOut() and section name
generation. In the new world, an object that implements the
interface has the methods serializeSection() and
unserializeSection() that serialize into a named /subsection/ of
the current object. Calling serialize() serializes an object into
the current section.

* Move the name() method from Serializable to SimObject as it is no
longer needed for serialization. The fully qualified section name
is generated by the main serialization code on the fly as objects
serialize sub-objects.

* Add a scoped ScopedCheckpointSection helper class. Some objects
need to serialize data structures, that are not deriving from
Serializable, into subsections. Previously, this was done using
nameOut() and manual section name generation. To simplify this,
this changeset introduces a ScopedCheckpointSection() helper
class. When this class is instantiated, it adds a new /subsection/
and subsequent serialization calls during the lifetime of this
helper class happen inside this section (or a subsection in case
of nested sections).

* The serialize() call is now const which prevents accidental state
manipulation during serialization. Objects that rely on modifying
state can use the serializeOld() call instead. The default
implementation simply calls serialize(). Note: The old-style calls
need to be explicitly called using the
serializeOld()/serializeSectionOld() style APIs. These are used by
default when serializing SimObjects.

* Both the input and output checkpoints now use their own named
types. This hides underlying checkpoint implementation from
objects that need checkpointing and makes it easier to change the
underlying checkpoint storage code.
10698:829adc48e175 Mon Feb 16 03:33:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> arch: Make readMiscRegNoEffect const throughout

Finally took the plunge and made this apply to all ISAs, not just ARM.
/gem5/src/arch/sparc/
H A Disa.hh11168:f98eb2da15a4 Mon Oct 12 04:07:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> misc: Remove redundant compiler-specific defines

This patch moves away from using M5_ATTR_OVERRIDE and the m5::hashmap
(and similar) abstractions, as these are no longer needed with gcc 4.7
and clang 3.1 as minimum compiler versions.
10935:acd48ddd725f Tue Jul 28 02:58:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> revert 5af8f40d8f2c
10934:5af8f40d8f2c Sun Jul 26 11:21:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> cpu: implements vector registers

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.
10905:a6ca6831e775 Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Refactor the serialization base class

Objects that are can be serialized are supposed to inherit from the
Serializable class. This class is meant to provide a unified API for
such objects. However, so far it has mainly been used by SimObjects
due to some fundamental design limitations. This changeset redesigns
to the serialization interface to make it more generic and hide the
underlying checkpoint storage. Specifically:

* Add a set of APIs to serialize into a subsection of the current
object. Previously, objects that needed this functionality would
use ad-hoc solutions using nameOut() and section name
generation. In the new world, an object that implements the
interface has the methods serializeSection() and
unserializeSection() that serialize into a named /subsection/ of
the current object. Calling serialize() serializes an object into
the current section.

* Move the name() method from Serializable to SimObject as it is no
longer needed for serialization. The fully qualified section name
is generated by the main serialization code on the fly as objects
serialize sub-objects.

* Add a scoped ScopedCheckpointSection helper class. Some objects
need to serialize data structures, that are not deriving from
Serializable, into subsections. Previously, this was done using
nameOut() and manual section name generation. To simplify this,
this changeset introduces a ScopedCheckpointSection() helper
class. When this class is instantiated, it adds a new /subsection/
and subsequent serialization calls during the lifetime of this
helper class happen inside this section (or a subsection in case
of nested sections).

* The serialize() call is now const which prevents accidental state
manipulation during serialization. Objects that rely on modifying
state can use the serializeOld() call instead. The default
implementation simply calls serialize(). Note: The old-style calls
need to be explicitly called using the
serializeOld()/serializeSectionOld() style APIs. These are used by
default when serializing SimObjects.

* Both the input and output checkpoints now use their own named
types. This hides underlying checkpoint implementation from
objects that need checkpointing and makes it easier to change the
underlying checkpoint storage code.
10698:829adc48e175 Mon Feb 16 03:33:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> arch: Make readMiscRegNoEffect const throughout

Finally took the plunge and made this apply to all ISAs, not just ARM.
/gem5/src/arch/x86/
H A Disa.hh11168:f98eb2da15a4 Mon Oct 12 04:07:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> misc: Remove redundant compiler-specific defines

This patch moves away from using M5_ATTR_OVERRIDE and the m5::hashmap
(and similar) abstractions, as these are no longer needed with gcc 4.7
and clang 3.1 as minimum compiler versions.
10935:acd48ddd725f Tue Jul 28 02:58:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> revert 5af8f40d8f2c
10934:5af8f40d8f2c Sun Jul 26 11:21:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> cpu: implements vector registers

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.
10905:a6ca6831e775 Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Refactor the serialization base class

Objects that are can be serialized are supposed to inherit from the
Serializable class. This class is meant to provide a unified API for
such objects. However, so far it has mainly been used by SimObjects
due to some fundamental design limitations. This changeset redesigns
to the serialization interface to make it more generic and hide the
underlying checkpoint storage. Specifically:

* Add a set of APIs to serialize into a subsection of the current
object. Previously, objects that needed this functionality would
use ad-hoc solutions using nameOut() and section name
generation. In the new world, an object that implements the
interface has the methods serializeSection() and
unserializeSection() that serialize into a named /subsection/ of
the current object. Calling serialize() serializes an object into
the current section.

* Move the name() method from Serializable to SimObject as it is no
longer needed for serialization. The fully qualified section name
is generated by the main serialization code on the fly as objects
serialize sub-objects.

* Add a scoped ScopedCheckpointSection helper class. Some objects
need to serialize data structures, that are not deriving from
Serializable, into subsections. Previously, this was done using
nameOut() and manual section name generation. To simplify this,
this changeset introduces a ScopedCheckpointSection() helper
class. When this class is instantiated, it adds a new /subsection/
and subsequent serialization calls during the lifetime of this
helper class happen inside this section (or a subsection in case
of nested sections).

* The serialize() call is now const which prevents accidental state
manipulation during serialization. Objects that rely on modifying
state can use the serializeOld() call instead. The default
implementation simply calls serialize(). Note: The old-style calls
need to be explicitly called using the
serializeOld()/serializeSectionOld() style APIs. These are used by
default when serializing SimObjects.

* Both the input and output checkpoints now use their own named
types. This hides underlying checkpoint implementation from
objects that need checkpointing and makes it easier to change the
underlying checkpoint storage code.
10698:829adc48e175 Mon Feb 16 03:33:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> arch: Make readMiscRegNoEffect const throughout

Finally took the plunge and made this apply to all ISAs, not just ARM.
/gem5/src/dev/arm/
H A Dgeneric_timer.hh11168:f98eb2da15a4 Mon Oct 12 04:07:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> misc: Remove redundant compiler-specific defines

This patch moves away from using M5_ATTR_OVERRIDE and the m5::hashmap
(and similar) abstractions, as these are no longer needed with gcc 4.7
and clang 3.1 as minimum compiler versions.
10905:a6ca6831e775 Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Refactor the serialization base class

Objects that are can be serialized are supposed to inherit from the
Serializable class. This class is meant to provide a unified API for
such objects. However, so far it has mainly been used by SimObjects
due to some fundamental design limitations. This changeset redesigns
to the serialization interface to make it more generic and hide the
underlying checkpoint storage. Specifically:

* Add a set of APIs to serialize into a subsection of the current
object. Previously, objects that needed this functionality would
use ad-hoc solutions using nameOut() and section name
generation. In the new world, an object that implements the
interface has the methods serializeSection() and
unserializeSection() that serialize into a named /subsection/ of
the current object. Calling serialize() serializes an object into
the current section.

* Move the name() method from Serializable to SimObject as it is no
longer needed for serialization. The fully qualified section name
is generated by the main serialization code on the fly as objects
serialize sub-objects.

* Add a scoped ScopedCheckpointSection helper class. Some objects
need to serialize data structures, that are not deriving from
Serializable, into subsections. Previously, this was done using
nameOut() and manual section name generation. To simplify this,
this changeset introduces a ScopedCheckpointSection() helper
class. When this class is instantiated, it adds a new /subsection/
and subsequent serialization calls during the lifetime of this
helper class happen inside this section (or a subsection in case
of nested sections).

* The serialize() call is now const which prevents accidental state
manipulation during serialization. Objects that rely on modifying
state can use the serializeOld() call instead. The default
implementation simply calls serialize(). Note: The old-style calls
need to be explicitly called using the
serializeOld()/serializeSectionOld() style APIs. These are used by
default when serializing SimObjects.

* Both the input and output checkpoints now use their own named
types. This hides underlying checkpoint implementation from
objects that need checkpointing and makes it easier to change the
underlying checkpoint storage code.
10847:1826ee736709 Sat May 23 08:46:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> arm, dev: Add support for a memory mapped generic timer

There are cases when we don't want to use a system register mapped
generic timer, but can't use the SP804. For example, when using KVM on
aarch64, we want to intercept accesses to the generic timer, but can't
do so if it is using the system register interface. In such cases,
we need to use a memory-mapped generic timer.

This changeset adds a device model that implements the memory mapped
generic timer interface. The current implementation only supports a
single frame (i.e., one virtual timer and one physical timer).
10845:75df7a87be83 Sat May 23 08:46:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> dev, arm: Add virtual timers to the generic timer model

The generic timer model currently does not support virtual
counters. Virtual and physical counters both tick with the same
frequency. However, virtual timers allow a hypervisor to set an offset
that is subtracted from the counter when it is read. This enables the
hypervisor to present a time base that ticks with virtual time in the
VM (i.e., doesn't tick when the VM isn't running). Modern Linux
kernels generally assume that virtual counters exist and try to use
them by default.
10844:8551af601f75 Sat May 23 08:46:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> dev, arm: Refactor and clean up the generic timer model

This changeset cleans up the generic timer a bit and moves most of the
register juggling from the ISA code into a separate class in the same
source file as the rest of the generic timer. It also removes the
assumption that there is always 8 or fewer CPUs in the system. Instead
of having a fixed limit, we now instantiate per-core timers as they
are requested. This is all in preparation for other patches that add
support for virtual timers and a memory mapped interface.
/gem5/src/cpu/minor/
H A Dcpu.hh11169:44b5c183c3cd Mon Oct 12 04:08:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> misc: Add explicit overrides and fix other clang >= 3.5 issues

This patch adds explicit overrides as this is now required when using
"-Wall" with clang >= 3.5, the latter now part of the most recent
XCode. The patch consequently removes "virtual" for those methods
where "override" is added. The latter should be enough of an
indication.

As part of this patch, a few minor issues that clang >= 3.5 complains
about are also resolved (unused methods and variables).
11168:f98eb2da15a4 Mon Oct 12 04:07:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> misc: Remove redundant compiler-specific defines

This patch moves away from using M5_ATTR_OVERRIDE and the m5::hashmap
(and similar) abstractions, as these are no longer needed with gcc 4.7
and clang 3.1 as minimum compiler versions.
11151:ca4ea9b5c052 Wed Sep 30 12:14:00 EDT 2015 Mitch Hayenga <mitch.hayenga@arm.com> cpu,isa,mem: Add per-thread wakeup logic

Changes wakeup functionality so that only specific threads on SMT
capable cpus are woken.
10913:38dbdeea7f1f Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Refactor and simplify the drain API

The drain() call currently passes around a DrainManager pointer, which
is now completely pointless since there is only ever one global
DrainManager in the system. It also contains vestiges from the time
when SimObjects had to keep track of their child objects that needed
draining.

This changeset moves all of the DrainState handling to the Drainable
base class and changes the drain() and drainResume() calls to reflect
this. Particularly, the drain() call has been updated to take no
parameters (the DrainManager argument isn't needed) and return a
DrainState instead of an unsigned integer (there is no point returning
anything other than 0 or 1 any more). Drainable objects should return
either DrainState::Draining (equivalent to returning 1 in the old
system) if they need more time to drain or DrainState::Drained
(equivalent to returning 0 in the old system) if they are already in a
consistent state. Returning DrainState::Running is considered an
error.

Drain done signalling is now done through the signalDrainDone() method
in the Drainable class instead of using the DrainManager directly. The
new call checks if the state of the object is DrainState::Draining
before notifying the drain manager. This means that it is safe to call
signalDrainDone() without first checking if the simulator has
requested draining. The intention here is to reduce the code needed to
implement draining in simple objects.
10905:a6ca6831e775 Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Refactor the serialization base class

Objects that are can be serialized are supposed to inherit from the
Serializable class. This class is meant to provide a unified API for
such objects. However, so far it has mainly been used by SimObjects
due to some fundamental design limitations. This changeset redesigns
to the serialization interface to make it more generic and hide the
underlying checkpoint storage. Specifically:

* Add a set of APIs to serialize into a subsection of the current
object. Previously, objects that needed this functionality would
use ad-hoc solutions using nameOut() and section name
generation. In the new world, an object that implements the
interface has the methods serializeSection() and
unserializeSection() that serialize into a named /subsection/ of
the current object. Calling serialize() serializes an object into
the current section.

* Move the name() method from Serializable to SimObject as it is no
longer needed for serialization. The fully qualified section name
is generated by the main serialization code on the fly as objects
serialize sub-objects.

* Add a scoped ScopedCheckpointSection helper class. Some objects
need to serialize data structures, that are not deriving from
Serializable, into subsections. Previously, this was done using
nameOut() and manual section name generation. To simplify this,
this changeset introduces a ScopedCheckpointSection() helper
class. When this class is instantiated, it adds a new /subsection/
and subsequent serialization calls during the lifetime of this
helper class happen inside this section (or a subsection in case
of nested sections).

* The serialize() call is now const which prevents accidental state
manipulation during serialization. Objects that rely on modifying
state can use the serializeOld() call instead. The default
implementation simply calls serialize(). Note: The old-style calls
need to be explicitly called using the
serializeOld()/serializeSectionOld() style APIs. These are used by
default when serializing SimObjects.

* Both the input and output checkpoints now use their own named
types. This hides underlying checkpoint implementation from
objects that need checkpointing and makes it easier to change the
underlying checkpoint storage code.
H A Dcpu.cc11151:ca4ea9b5c052 Wed Sep 30 12:14:00 EDT 2015 Mitch Hayenga <mitch.hayenga@arm.com> cpu,isa,mem: Add per-thread wakeup logic

Changes wakeup functionality so that only specific threads on SMT
capable cpus are woken.
10949:7fc527ab626a Fri Jul 31 12:04:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> cpu: Fix Minor drain issues when switched out

The Minor CPU currently doesn't drain properly when it is switched
out. This happens because Fetch 1 expects to be in the FetchHalted
state when it is drained. However, because the CPU is switched out, it
is stuck in the FetchWaitingForPC state. Fix this by ignoring drain
requests and returning DrainState::Drained from MinorCPU::drain() if
the CPU is switched out. This is always safe since a switched out CPU,
by definition, doesn't have any instructions in flight.
10946:6f10e35b57d1 Thu Jul 30 05:15:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> cpu: Only activate thread 0 in Minor if the CPU is active

Minor currently activates thread 0 in startup() to work around an
issue where activateContext() is called from LiveProcess before the
process entry point is known. When activateContext() is called, Minor
creates a branch instruction to the process's entry point. The first
time it is called, the branch points to an undefined location (0). The
call in startup() updates the branch to point to the actual entry
point.

When instantiating a switched out Minor CPU, it still tries to
activate thread 0. This is clearly incorrect since a switched out CPU
can't have any active threads. This changeset adds a check to ensure
that the thread is active before reactivating it.
10945:369861e3d5af Thu Jul 30 05:15:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> cpu: Fix drain issues in the Minor CPU

The drain refactor patches introduced a couple of bugs in the way
Minor handles draining. This patch fixes an incorrect assert and a
case of infinite recursion when the CPU signals drain done.
10913:38dbdeea7f1f Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Refactor and simplify the drain API

The drain() call currently passes around a DrainManager pointer, which
is now completely pointless since there is only ever one global
DrainManager in the system. It also contains vestiges from the time
when SimObjects had to keep track of their child objects that needed
draining.

This changeset moves all of the DrainState handling to the Drainable
base class and changes the drain() and drainResume() calls to reflect
this. Particularly, the drain() call has been updated to take no
parameters (the DrainManager argument isn't needed) and return a
DrainState instead of an unsigned integer (there is no point returning
anything other than 0 or 1 any more). Drainable objects should return
either DrainState::Draining (equivalent to returning 1 in the old
system) if they need more time to drain or DrainState::Drained
(equivalent to returning 0 in the old system) if they are already in a
consistent state. Returning DrainState::Running is considered an
error.

Drain done signalling is now done through the signalDrainDone() method
in the Drainable class instead of using the DrainManager directly. The
new call checks if the state of the object is DrainState::Draining
before notifying the drain manager. This means that it is safe to call
signalDrainDone() without first checking if the simulator has
requested draining. The intention here is to reduce the code needed to
implement draining in simple objects.
10910:32f3d1c454ec Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Make the drain state a global typed enum

The drain state enum is currently a part of the Drainable
interface. The same state machine will be used by the DrainManager to
identify the global state of the simulator. Make the drain state a
global typed enum to better cater for this usage scenario.
10905:a6ca6831e775 Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Refactor the serialization base class

Objects that are can be serialized are supposed to inherit from the
Serializable class. This class is meant to provide a unified API for
such objects. However, so far it has mainly been used by SimObjects
due to some fundamental design limitations. This changeset redesigns
to the serialization interface to make it more generic and hide the
underlying checkpoint storage. Specifically:

* Add a set of APIs to serialize into a subsection of the current
object. Previously, objects that needed this functionality would
use ad-hoc solutions using nameOut() and section name
generation. In the new world, an object that implements the
interface has the methods serializeSection() and
unserializeSection() that serialize into a named /subsection/ of
the current object. Calling serialize() serializes an object into
the current section.

* Move the name() method from Serializable to SimObject as it is no
longer needed for serialization. The fully qualified section name
is generated by the main serialization code on the fly as objects
serialize sub-objects.

* Add a scoped ScopedCheckpointSection helper class. Some objects
need to serialize data structures, that are not deriving from
Serializable, into subsections. Previously, this was done using
nameOut() and manual section name generation. To simplify this,
this changeset introduces a ScopedCheckpointSection() helper
class. When this class is instantiated, it adds a new /subsection/
and subsequent serialization calls during the lifetime of this
helper class happen inside this section (or a subsection in case
of nested sections).

* The serialize() call is now const which prevents accidental state
manipulation during serialization. Objects that rely on modifying
state can use the serializeOld() call instead. The default
implementation simply calls serialize(). Note: The old-style calls
need to be explicitly called using the
serializeOld()/serializeSectionOld() style APIs. These are used by
default when serializing SimObjects.

* Both the input and output checkpoints now use their own named
types. This hides underlying checkpoint implementation from
objects that need checkpointing and makes it easier to change the
underlying checkpoint storage code.
/gem5/src/mem/
H A Dsnoop_filter.cc11287:0d5bbeaeb8ca Thu Dec 31 09:34:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Do not rely on the NeedsWritable flag for responses

This patch removes the NeedsWritable flag for all responses, as it is
really only the request that needs a writable response. The response,
on the other hand, should in these cases always provide the line in a
writable state, as indicated by the hasSharers flag not being set.

When we send requests that has NeedsWritable set, the response will
always have the hasSharers flag not set. Additionally, there are cases
where the request did not have NeedsWritable set, and we still get a
writable response with the hasSharers flag not set. This never happens
on snoops, but is used by downstream caches to pass ownership
upstream.

As part of this patch, the affected response types are updated, and
the snoop filter is similarly modified to check only the hasSharers
flag (as it should). A sanity check is also added to the packet class,
asserting that we never look at the NeedsWritable flag for responses.

No regressions are affected.
11284:b3926db25371 Thu Dec 31 09:32:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Make cache terminology easier to understand

This patch changes the name of a bunch of packet flags and MSHR member
functions and variables to make the coherency protocol easier to
understand. In addition the patch adds and updates lots of
descriptions, explicitly spelling out assumptions.

The following name changes are made:

* the packet memInhibit flag is renamed to cacheResponding

* the packet sharedAsserted flag is renamed to hasSharers

* the packet NeedsExclusive attribute is renamed to NeedsWritable

* the packet isSupplyExclusive is renamed responderHadWritable

* the MSHR pendingDirty is renamed to pendingModified

The cache states, Modified, Owned, Exclusive, Shared are also called
out in the cache and MSHR code to make it easier to understand.
11199:929fd978ab4e Fri Nov 06 03:26:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Add an option to perform clean writebacks from caches

This patch adds the necessary commands and cache functionality to
allow clean writebacks. This functionality is crucial, especially when
having exclusive (victim) caches. For example, if read-only L1
instruction caches are not sending clean writebacks, there will never
be any spills from the L1 to the L2. At the moment the cache model
defaults to not sending clean writebacks, and this should possibly be
re-evaluated.

The implementation of clean writebacks relies on a new packet command
WritebackClean, which acts much like a Writeback (renamed
WritebackDirty), and also much like a CleanEvict. On eviction of a
clean block the cache either sends a clean evict, or a clean
writeback, and if any copies are still cached upstream the clean
evict/writeback is dropped. Similarly, if a clean evict/writeback
reaches a cache where there are outstanding MSHRs for the block, the
packet is dropped. In the typical case though, the clean writeback
allocates a block in the downstream cache, and marks it writable if
the evicted block was writable.

The patch changes the O3_ARM_v7a L1 cache configuration and the
default L1 caches in config/common/Caches.py
11135:9d09dab39689 Fri Sep 25 07:26:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Comment clean-up for the snoop filter

Merely fixing up some style issues and adding more comments.
11134:dfa51840de1f Fri Sep 25 07:26:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Avoid adding and then removing empty snoop-filter items

This patch tidies up how we access the snoop filter for snoops, and
avoids adding items only to later remove them.
11132:fbd597034299 Fri Sep 25 07:26:00 EDT 2015 Ali Jafri <ali.jafri@arm.com> mem: Add snoop filters to L2 crossbars, and check size

This patch adds a snoop filter to the L2XBar. For now we refrain from
globally adding a snoop filter to the SystemXBar, since the latter is
also used in systems without caches. In scenarios without caches the
snoop filter will not see any writeback/clean evicts from the CPU
ports, despite the fact that they are snooping. To avoid inadvertent
use of the snoop filter in these cases we leave it out for now.

A size check is added to the snoop filter, merely to ensure it does
not grow beyond the total capacity of the caches above it. The size
has to be set manually, and a value of 8 MByte is choosen as suitably
high default.
11131:22e739752f47 Fri Sep 25 07:26:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Store snoop filter lookup result to avoid second lookup

This patch introduces a private member storing the iterator from the
lookupRequest call, such that it can be re-used when the request
eventually finishes. The method previously called updateRequest is
renamed finishRequest to make it more clear that the two functions
must be called together.
11129:48c02e8b0bbb Fri Sep 25 07:26:00 EDT 2015 Ali Jafri <ali.jafri@arm.com> mem: Add CleanEvict and Writeback support to snoop filters

This patch adds the functionality to properly track CleanEvicts and
Writebacks in the snoop filter. Previously there were no CleanEvicts, and
Writebacks did not send up snoops to ensure there were no copies in
caches above. Hence a writeback could never erase an entry from the
snoop filter.

When a CleanEvict message reaches a snoop filter, it confirms that the
BLOCK_CACHED flag is not set and resets the bits corresponding to the
CleanEvict address and port it arrived on. If none of the other peer
caches have (or have requested) the block, the snoop filter forwards
the CleanEvict to lower levels of memory. In case of a Writeback
message, the snoop filter checks if the BLOCK_CACHED flag is not set
and only then resets the bits corresponding to the Writeback
address. If any of the other peer caches have (or has requested) the
same block, the snoop filter sets the BLOCK_CACHED flag in the
Writeback before forwarding it to lower levels of memory heirarachy.
11128:b6532152a64a Fri Sep 25 07:26:00 EDT 2015 Ali Jafri <ali.jafri@arm.com> mem: Add check for snooping ports in the snoop filter

This patch prevents the snoop filter from creating items for requests
originating from non-snooping ports. The allocation decision is thus
based both on the cacheability of the line, and the snooping status of
the source port. Ultimately we should check if the source of the
packet is caching, since also the CPU ports are snooping (but not
allocating). Thus, at the moment we rely on the snoop filter being
used together with caches.

The patch also transitions to use the Packet::getBlockAddr in
determining the line address.
10883:9294c4a60251 Fri Jul 03 10:14:00 EDT 2015 Ali Jafri <ali.jafri@arm.com> mem: Add clean evicts to improve snoop filter tracking

This patch adds eviction notices to the caches, to provide accurate
tracking of cache blocks in snoop filters. We add the CleanEvict
message to the memory heirarchy and use both CleanEvicts and
Writebacks with BLOCK_CACHED flags to propagate notice of clean and
dirty evictions respectively, down the memory hierarchy. Note that the
BLOCK_CACHED flag indicates whether there exist any copies of the
evicted block in the caches above the evicting cache.

The purpose of the CleanEvict message is to notify snoop filters of
silent evictions in the relevant caches. The CleanEvict message
behaves much like a Writeback. CleanEvict is a write and a request but
unlike a Writeback, CleanEvict does not have data and does not need
exclusive access to the block. The cache generates the CleanEvict
message on a fill resulting in eviction of a clean block. Before
travelling downwards CleanEvict requests generate zero-time snoop
requests to check if the same block is cached in upper levels of the
memory heirarchy. If the block exists, the cache discards the
CleanEvict message. The snoops check the tags, writeback queue and the
MSHRs of upper level caches in a manner similar to snoops generated
from HardPFReqs. Currently CleanEvicts keep travelling towards main
memory unless they encounter the block corresponding to their address
or reach main memory (since we have no well defined point of
serialisation). Main memory simply discards CleanEvict messages.

We have modified the behavior of Writebacks, such that they generate
snoops to check for the presence of blocks in upper level caches. It
is possible in our current implmentation for a lower level cache to be
writing back a block while a shared copy of the same block exists in
the upper level cache. If the snoops find the same block in upper
level caches, we set the BLOCK_CACHED flag in the Writeback message.

We have also added logic to account for interaction of other message
types with CleanEvicts waiting in the writeback queue. A simple
example is of a response arriving at a cache removing any CleanEvicts
to the same address from the cache's writeback queue.
H A Dpacket_queue.cc11207:7b7e352f8d7f Mon Jul 20 10:15:00 EDT 2015 Brad Beckmann <Brad.Beckmann@amd.com> mem: add boolean to disable PacketQueue's size sanity check

the sanity check, while generally useful for exposing memory system bugs,
may be spurious with respect to GPU workloads, which may generate many more
requests than typical CPU workloads. the large number of requests generated
by the GPU may cause the req/resp queues to back up, thus queueing more than
100 packets.
11195:6f8b2a005abb Fri Nov 06 03:26:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Order packet queue only on matching addresses

Instead of conservatively enforcing order for all packets, which may
negatively impact the simulated-system performance, this patch updates
the packet queue such that it only applies the restriction if there
are already packets with the same address in the queue.

The basic need for the order enforcement is due to coherency
interactions where requests/responses to the same cache line must not
over-take each other. We rely on the fact that any packet that needs
order enforcement will have a block-aligned address. Thus, there is no
need for the queue to know about the cacheline size.
10922:5ee72f4b2931 Mon Jul 13 08:46:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Fix (ab)use of emplace to avoid temporary object creation
10913:38dbdeea7f1f Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Refactor and simplify the drain API

The drain() call currently passes around a DrainManager pointer, which
is now completely pointless since there is only ever one global
DrainManager in the system. It also contains vestiges from the time
when SimObjects had to keep track of their child objects that needed
draining.

This changeset moves all of the DrainState handling to the Drainable
base class and changes the drain() and drainResume() calls to reflect
this. Particularly, the drain() call has been updated to take no
parameters (the DrainManager argument isn't needed) and return a
DrainState instead of an unsigned integer (there is no point returning
anything other than 0 or 1 any more). Drainable objects should return
either DrainState::Draining (equivalent to returning 1 in the old
system) if they need more time to drain or DrainState::Drained
(equivalent to returning 0 in the old system) if they are already in a
consistent state. Returning DrainState::Running is considered an
error.

Drain done signalling is now done through the signalDrainDone() method
in the Drainable class instead of using the DrainManager directly. The
new call checks if the state of the object is DrainState::Draining
before notifying the drain manager. This means that it is safe to call
signalDrainDone() without first checking if the simulator has
requested draining. The intention here is to reduce the code needed to
implement draining in simple objects.
10745:791e4619919d Thu Mar 19 04:06:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Use emplace front/back for deferred packets

Embrace C++11 for the deferred packets as we actually store the
objects in the data structure, and not just pointers.
10722:886d2458e0d6 Mon Mar 02 04:00:00 EST 2015 Stephan Diestelhorst <stephan.diestelhorst@arm.com> mem: Add option to force in-order insertion in PacketQueue

By default, the packet queue is ordered by the ticks of the to-be-sent
packages. With the recent modifications of packages sinking their header time
when their resposne leaves the caches, there could be cases of MSHR targets
being allocated and ordered A, B, but their responses being sent out in the
order B,A. This led to inconsistencies in bus traffic, in particular the snoop
filter observing first a ReadExResp and later a ReadRespWithInv. Logically,
these were ordered the other way around behind the MSHR, but due to the timing
adjustments when inserting into the PacketQueue, they were sent out in the
wrong order on the bus, confusing the snoop filter.

This patch adds a flag (off by default) such that these special cases can
request in-order insertion into the packet queue, which might offset timing
slighty. This is expected to occur rarely and not affect timing results.
10713:eddb533708cb Mon Mar 02 04:00:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Split port retry for all different packet classes

This patch fixes a long-standing isue with the port flow
control. Before this patch the retry mechanism was shared between all
different packet classes. As a result, a snoop response could get
stuck behind a request waiting for a retry, even if the send/recv
functions were split. This caused message-dependent deadlocks in
stress-test scenarios.

The patch splits the retry into one per packet (message) class. Thus,
sendTimingReq has a corresponding recvReqRetry, sendTimingResp has
recvRespRetry etc. Most of the changes to the code involve simply
clarifying what type of request a specific object was accepting.

The biggest change in functionality is in the cache downstream packet
queue, facing the memory. This queue was shared by requests and snoop
responses, and it is now split into two queues, each with their own
flow control, but the same physical MasterPort. These changes fixes
the previously seen deadlocks.
H A Dsimple_mem.cc11284:b3926db25371 Thu Dec 31 09:32:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Make cache terminology easier to understand

This patch changes the name of a bunch of packet flags and MSHR member
functions and variables to make the coherency protocol easier to
understand. In addition the patch adds and updates lots of
descriptions, explicitly spelling out assumptions.

The following name changes are made:

* the packet memInhibit flag is renamed to cacheResponding

* the packet sharedAsserted flag is renamed to hasSharers

* the packet NeedsExclusive attribute is renamed to NeedsWritable

* the packet isSupplyExclusive is renamed responderHadWritable

* the MSHR pendingDirty is renamed to pendingModified

The cache states, Modified, Owned, Exclusive, Shared are also called
out in the cache and MSHR code to make it easier to understand.
11193:564e2e7e86f4 Fri Nov 06 03:26:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Use the packet delays and do not just zero them out

This patch updates the I/O devices, bridge and simple memory to take
the packet header and payload delay into account in their latency
calculations. In all cases we add the header delay, i.e. the
accumulated pipeline delay of any crossbars, and the payload delay
needed for deserialisation of any payload.

Due to the additional unknown latency contribution, the packet queue
of the simple memory is changed to use insertion sorting based on the
time stamp. Moreover, since the memory hands out exclusive (non
shared) responses, we also need to ensure ordering for reads to the
same address.
11192:4c28abcf8249 Fri Nov 06 03:26:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Align rules for sinking inhibited packets at the slave

This patch aligns how the memory-system slaves, i.e. the various
memory controllers and the bridge, identify and deal with sinking of
inhibited packets that are only useful within the coherent part of the
memory system.

In the future we could shift the onus to the crossbar, and add a
parameter "is_point_of_coherence" that would allow it to sink the
aforementioned packets.
11190:0964165d1857 Fri Nov 06 03:26:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Unify delayed packet deletion

This patch unifies how we deal with delayed packet deletion, where the
receiving slave is responsible for deleting the packet, but the
sending agent (e.g. a cache) is still relying on the pointer until the
call to sendTimingReq completes. Previously we used a mix of a
deletion vector and a construct using unique_ptr. With this patch we
ensure all slaves use the latter approach.
10922:5ee72f4b2931 Mon Jul 13 08:46:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Fix (ab)use of emplace to avoid temporary object creation
10913:38dbdeea7f1f Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Refactor and simplify the drain API

The drain() call currently passes around a DrainManager pointer, which
is now completely pointless since there is only ever one global
DrainManager in the system. It also contains vestiges from the time
when SimObjects had to keep track of their child objects that needed
draining.

This changeset moves all of the DrainState handling to the Drainable
base class and changes the drain() and drainResume() calls to reflect
this. Particularly, the drain() call has been updated to take no
parameters (the DrainManager argument isn't needed) and return a
DrainState instead of an unsigned integer (there is no point returning
anything other than 0 or 1 any more). Drainable objects should return
either DrainState::Draining (equivalent to returning 1 in the old
system) if they need more time to drain or DrainState::Drained
(equivalent to returning 0 in the old system) if they are already in a
consistent state. Returning DrainState::Running is considered an
error.

Drain done signalling is now done through the signalDrainDone() method
in the Drainable class instead of using the DrainManager directly. The
new call checks if the state of the object is DrainState::Draining
before notifying the drain manager. This means that it is safe to call
signalDrainDone() without first checking if the simulator has
requested draining. The intention here is to reduce the code needed to
implement draining in simple objects.
10910:32f3d1c454ec Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Make the drain state a global typed enum

The drain state enum is currently a part of the Drainable
interface. The same state machine will be used by the DrainManager to
identify the global state of the simulator. Make the drain state a
global typed enum to better cater for this usage scenario.
10745:791e4619919d Thu Mar 19 04:06:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Use emplace front/back for deferred packets

Embrace C++11 for the deferred packets as we actually store the
objects in the data structure, and not just pointers.
10713:eddb533708cb Mon Mar 02 04:00:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Split port retry for all different packet classes

This patch fixes a long-standing isue with the port flow
control. Before this patch the retry mechanism was shared between all
different packet classes. As a result, a snoop response could get
stuck behind a request waiting for a retry, even if the send/recv
functions were split. This caused message-dependent deadlocks in
stress-test scenarios.

The patch splits the retry into one per packet (message) class. Thus,
sendTimingReq has a corresponding recvReqRetry, sendTimingResp has
recvRespRetry etc. Most of the changes to the code involve simply
clarifying what type of request a specific object was accepting.

The biggest change in functionality is in the cache downstream packet
queue, facing the memory. This queue was shared by requests and snoop
responses, and it is now split into two queues, each with their own
flow control, but the same physical MasterPort. These changes fixes
the previously seen deadlocks.
10694:1a6785e37d81 Wed Feb 11 10:23:00 EST 2015 Marco Balboni <Marco.Balboni@ARM.com> mem: Clarification of packet crossbar timings

This patch clarifies the packet timings annotated
when going through a crossbar.

The old 'firstWordDelay' is replaced by 'headerDelay' that represents
the delay associated to the delivery of the header of the packet.

The old 'lastWordDelay' is replaced by 'payloadDelay' that represents
the delay needed to processing the payload of the packet.

For now the uses and values remain identical. However, going forward
the payloadDelay will be additive, and not include the
headerDelay. Follow-on patches will make the headerDelay capture the
pipeline latency incurred in the crossbar, whereas the payloadDelay
will capture the additional serialisation delay.
/gem5/src/mem/ruby/slicc_interface/
H A DAbstractController.hh11309:9be8a40026df Mon Jul 20 10:15:00 EDT 2015 David Hashe <david.hashe@amd.com> ruby: split CPU and GPU latency stats
11121:370488a55495 Wed Sep 23 12:23:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: abstract controller: mark some variables as const
11049:dfb0aa3f0649 Wed Aug 19 11:02:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: reverts to changeset: bf82f1f7b040
11038:6d709f3c4c09 Fri Aug 14 20:28:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: abstract controller: mark some variables as const
11025:4872dbdea907 Fri Aug 14 01:04:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: replace Address by Addr
This patch eliminates the type Address defined by the ruby memory system.
This memory system would now use the type Addr that is in use by the
rest of the system.
11021:e8a6637afa4c Fri Aug 14 01:19:00 EDT 2015 Joel Hestness <jthestness@gmail.com> ruby: Expose MessageBuffers as SimObjects

Expose MessageBuffers from SLICC controllers as SimObjects that can be
manipulated in Python. This patch has numerous benefits:
1) First and foremost, it exposes MessageBuffers as SimObjects that can be
manipulated in Python code. This allows parameters to be set and checked in
Python code to avoid obfuscating parameters within protocol files. Further, now
as SimObjects, MessageBuffer parameters are printed to config output files as a
way to track parameters across simulations (e.g. buffer sizes)

2) Cleans up special-case code for responseFromMemory buffers, and aligns their
instantiation and use with mandatoryQueue buffers. These two special buffers
are the only MessageBuffers that are exposed to components outside of SLICC
controllers, and they're both slave ends of these buffers. They should be
exposed outside of SLICC in the same way, and this patch does it.

3) Distinguishes buffer-specific parameters from buffer-to-network parameters.
Specifically, buffer size, randomization, ordering, recycle latency, and ports
are all specific to a MessageBuffer, while the virtual network ID and type are
intrinsics of how the buffer is connected to network ports. The former are
specified in the Python object, while the latter are specified in the
controller *.sm files. Unlike buffer-specific parameters, which may need to
change depending on the simulated system structure, buffer-to-network
parameters can be specified statically for most or all different simulated
systems.
10977:9b3b9be42dd9 Mon Jul 20 10:15:00 EDT 2015 David Hashe <david.hashe@amd.com> ruby: Fix for stallAndWait bug

It was previously possible for a stalled message to be reordered after an
incomming message. This patch ensures that any stalled message stays in its
original request order.
10963:51f40b101a56 Mon Jul 20 10:15:00 EDT 2015 David Hashe <david.hashe@amd.com> slicc: support for multiple message types on the same buffer

This patch allows SLICC protocols to use more than one message type with a
message buffer. For example, you can declare two in ports as such:

in_port(ResponseQueue_in, ResponseMsg, responseFromDir, rank=3) { ... }
in_port(tgtResponseQueue_in, TgtResponseMsg, responseFromDir, rank=2) { ... }
10837:ecbab2522757 Tue May 19 11:56:00 EDT 2015 Joel Hestness <jthestness@gmail.com> ruby: Fix RubySystem warm-up and cool-down scope

The processes of warming up and cooling down Ruby caches are simulation-wide
processes, not just RubySystem instance-specific processes. Thus, the warm-up
and cool-down variables should be globally visible to any Ruby components
participating in either process. Make these variables static members and track
the warm-up and cool-down processes as appropriate.

This patch also has two side benefits:
1) It removes references to the RubySystem g_system_ptr, which are problematic
for allowing multiple RubySystem instances in a single simulation. Warmup and
cooldown variables being static (global) reduces the need for instance-specific
dereferences through the RubySystem.
2) From the AbstractController, it removes local RubySystem pointers, which are
used inconsistently with other uses of the RubySystem: 11 other uses reference
the RubySystem with the g_system_ptr. Only sequencers have local pointers.
10783:631e736554c9 Mon Apr 13 18:33:00 EDT 2015 Lena Olson <lena@cs.wisc.edu> ruby: allow restoring from checkpoint when using DRAMCtrl

Restoring from a checkpoint with ruby + the DRAMCtrl memory model was not
working, because ruby and DRAMCtrl disagreed on the current tick during warmup.
Since there is no reason to do timing requests during warmup, use functional
requests instead.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
/gem5/src/sim/
H A Dsim_events.hh11169:44b5c183c3cd Mon Oct 12 04:08:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> misc: Add explicit overrides and fix other clang >= 3.5 issues

This patch adds explicit overrides as this is now required when using
"-Wall" with clang >= 3.5, the latter now part of the most recent
XCode. The patch consequently removes "virtual" for those methods
where "override" is added. The latter should be enough of an
indication.

As part of this patch, a few minor issues that clang >= 3.5 complains
about are also resolved (unused methods and variables).
11168:f98eb2da15a4 Mon Oct 12 04:07:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> misc: Remove redundant compiler-specific defines

This patch moves away from using M5_ATTR_OVERRIDE and the m5::hashmap
(and similar) abstractions, as these are no longer needed with gcc 4.7
and clang 3.1 as minimum compiler versions.
11070:d9560edaf0a9 Tue Sep 01 08:41:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Remove autoserialize support for exit events

This changeset removes the support for the autoserialize parameter in
GlobalSimLoopExitEvent (including exitSimLoop()) and
LocalSimLoopExitEvent.

Auto-serialization of the LocalSimLoopExitEvent was never used, so
this is not expected to affect anything. However, it was sometimes
used for GlobalSimLoopExitEvent. Unfortunately, serialization of
global events has never been supported, so checkpoints with such
events will currently cause simulation panics.

The serialize parameter to exitSimLoop() has been left in-place to
maintain API compatibility (removing it would affect m5ops). Instead
of just dropping it, we now print a warning if the parameter is set
and the exit event is scheduled in the future (i.e., not at the
current tick).
10906:3ab1d7ed6545 Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Fix broken event unserialization

Events expected to be unserialized using an event-specific
unserializeEvent call. This call was never actually used, which meant
the events relying on it never got unserialized (or scheduled after
unserialization).

Instead of relying on a custom call, we now use the normal
serialization code again. In order to schedule the event correctly,
the parrent object is expected to use the
EventQueue::checkpointReschedule() call. This happens automatically
for events that are serialized using the AutoSerialize mechanism.
10905:a6ca6831e775 Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Refactor the serialization base class

Objects that are can be serialized are supposed to inherit from the
Serializable class. This class is meant to provide a unified API for
such objects. However, so far it has mainly been used by SimObjects
due to some fundamental design limitations. This changeset redesigns
to the serialization interface to make it more generic and hide the
underlying checkpoint storage. Specifically:

* Add a set of APIs to serialize into a subsection of the current
object. Previously, objects that needed this functionality would
use ad-hoc solutions using nameOut() and section name
generation. In the new world, an object that implements the
interface has the methods serializeSection() and
unserializeSection() that serialize into a named /subsection/ of
the current object. Calling serialize() serializes an object into
the current section.

* Move the name() method from Serializable to SimObject as it is no
longer needed for serialization. The fully qualified section name
is generated by the main serialization code on the fly as objects
serialize sub-objects.

* Add a scoped ScopedCheckpointSection helper class. Some objects
need to serialize data structures, that are not deriving from
Serializable, into subsections. Previously, this was done using
nameOut() and manual section name generation. To simplify this,
this changeset introduces a ScopedCheckpointSection() helper
class. When this class is instantiated, it adds a new /subsection/
and subsequent serialization calls during the lifetime of this
helper class happen inside this section (or a subsection in case
of nested sections).

* The serialize() call is now const which prevents accidental state
manipulation during serialization. Objects that rely on modifying
state can use the serializeOld() call instead. The default
implementation simply calls serialize(). Note: The old-style calls
need to be explicitly called using the
serializeOld()/serializeSectionOld() style APIs. These are used by
default when serializing SimObjects.

* Both the input and output checkpoints now use their own named
types. This hides underlying checkpoint implementation from
objects that need checkpointing and makes it easier to change the
underlying checkpoint storage code.
10762:fe0972727902 Thu Mar 26 11:16:00 EDT 2015 Curtis Dunham <Curtis.Dunham@arm.com> sim: Update limit_event reuse to final version

Matching final version on reviewboard.
10756:f9c0692f73ec Mon Mar 23 06:57:00 EDT 2015 Curtis Dunham <Curtis.Dunham@arm.com> sim: Reuse the same limit_event in simulate()

This patch accomplishes two things:
1. Makes simulate()'s GlobalSimLoopExitEvent a singleton reused
across calls. This is slightly more efficient than recreating
it every time.
2. Gives callers to simulate() (especially other simulators) a
foolproof way of knowing that the simulation period ended
successfully by hitting the limit event. They can call
getLimitEvent() and compare it to the return
value of simulate().

This change was motivated by an ongoing effort to integrate gem5
and SST, with SST as the master sim and gem5 as the slave sim.
H A Dserialize.hh11240:651bf9238c11 Fri Dec 04 04:48:00 EST 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Get rid of the non-const serialize() method

The last SimObject using the legacy serialize API with non-const
methods has now been transitioned to the new API. This changeset
removes the serializeOld() methods from the serialization base class
as they are no longer used.
11077:fae097742b7e Wed Sep 02 16:23:00 EDT 2015 Curtis Dunham <Curtis.Dunham@arm.com> sim: tag-based checkpoint versioning

This commit addresses gem5 checkpoints' linear versioning bottleneck.
Since development is distributed across many private trees, there exists
a sort of 'race' for checkpoint version numbers: internally a checkpoint
version may be used but then resynchronizing with the external tree causes
a conflict on that version. This change replaces the linear version number
with a set of unique strings called tags. Now the only conflicts that can
arise are of tag names, where collisions are much easier to avoid.

The checkpoint upgrader (util/cpt_upgrader.py) upgrades the version
representation, as one would expect. Each tag version implements its
upgrader code in a python file in the util/cpt_upgraders directory
rather than adding a function to the upgrader script itself.

The version tags are stored in the 'Globals' section rather than 'root'
(as the version was previously) because 'Globals' gets unserialized
first and can provide a warning before any other unserialization errors
can occur.
11076:463a4b0f0dda Wed Sep 02 16:19:00 EDT 2015 Curtis Dunham <Curtis.Dunham@arm.com> sim: support checkpointing std::set<std::string>'s

This is in support of tag-based checkpoint versioning; the version tags
are stored in string sets. This commit adds such support.
11075:f959b7f89d4d Wed Sep 02 16:19:00 EDT 2015 Curtis Dunham <Curtis.Dunham@arm.com> sim: make warning for absent optional parameters optional

This is in support of tag-based checkpoint versioning. It should be
possible to examine an optional parameter in a checkpoint during
unserialization and not have it throw a warning.
11072:6a447a3138ef Tue Sep 01 10:28:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Remove broken AutoSerialize support from the event queue

Event auto-serialization no longer in use and has been broken ever
since the introduction of PDES support almost two years
ago. Additionally, serializing the individual event queues is
undesirable since it exposes the thread structure of the
simulator. What this means in practice is that the number of threads
in the simulator must be the same when taking a checkpoint and when
loading the checkpoint.

This changeset removes support for the AutoSerialize event flag and
the associated serialization code.
11069:c5388db11c76 Tue Sep 01 08:40:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Remove unused SerializeBuilder interface
11068:9c39ca645966 Tue Sep 01 08:40:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Replace fromInt/fromSimObject with decltype
11067:5379f099e488 Tue Sep 01 08:40:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Move SimObject resolver to sim_object.hh

The object resolver isn't serialization specific and shouldn't live in
serialize.hh. Move it to sim_object.hh since it queries to the
SimObject hierarchy.
10930:ddc3d96d6313 Fri Jul 24 03:25:00 EDT 2015 Brandon Potter <brandon.potter@amd.com> base: refactor process class (specifically FdMap and friends)

This patch extends the previous patch's alterations around fd_map. It cleans
up some of the uglier code in the process file and replaces it with a more
concise C++11 version. As part of the changes, the FdMap class is pulled out
of the Process class and receives its own file.
10908:235d75ea01d8 Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Add macros to serialize objects into a section

Add the SERIALIZE_OBJ / UNSERIALIZE_OBJ macros that serialize an
object into a subsection of the current checkpoint section.
/gem5/src/mem/ruby/profiler/
H A DProfiler.hh11309:9be8a40026df Mon Jul 20 10:15:00 EDT 2015 David Hashe <david.hashe@amd.com> ruby: split CPU and GPU latency stats
11172:9261e98e4501 Wed Oct 14 01:29:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: profiler: provide the number of vnets through ruby system

The aim is to ultimately do away with the static function
Network::getNumberOfVirtualNetworks().
11168:f98eb2da15a4 Mon Oct 12 04:07:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> misc: Remove redundant compiler-specific defines

This patch moves away from using M5_ATTR_OVERRIDE and the m5::hashmap
(and similar) abstractions, as these are no longer needed with gcc 4.7
and clang 3.1 as minimum compiler versions.
11049:dfb0aa3f0649 Wed Aug 19 11:02:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: reverts to changeset: bf82f1f7b040
11046:0cd13910b063 Fri Aug 14 20:28:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: profiler: provide the number of vnets through ruby system

The aim is to ultimately do away with the static function
Network::getNumberOfVirtualNetworks().
10920:58fbfddff18d Fri Jul 10 17:05:00 EDT 2015 Brandon Potter <brandon.potter@amd.com> ruby: replace global g_abs_controls with per-RubySystem var

This is another step in the process of removing global variables
from Ruby to enable multiple RubySystem instances in a single simulation.

The list of abstract controllers is per-RubySystem and should be
represented that way, rather than as a global.

Since this is the last remaining Ruby global variable, the
src/mem/ruby/Common/Global.* files are also removed.
10919:80069a602c83 Fri Jul 10 17:05:00 EDT 2015 Brandon Potter <brandon.potter@amd.com> ruby: replace global g_system_ptr with per-object pointers

This is another step in the process of removing global variables
from Ruby to enable multiple RubySystem instances in a single simulation.

With possibly multiple RubySystem objects, we can no longer use a global
variable to find "the" RubySystem object. Instead, each Ruby component
has to carry a pointer to the RubySystem object to which it belongs.
/gem5/src/mem/ruby/network/simple/
H A DSimpleNetwork.cc11171:60d4dfa3241a Wed Oct 14 01:29:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: remove unused functionalRead() function.

Not required since functional reads cannot rely on messages that are inflight.
11124:5d38dc2f7d66 Thu Sep 24 09:41:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: simple network: refactor code

Drops an unused variable and marks three variables as const.
11113:5a2e1b1b5c43 Wed Sep 16 13:10:00 EDT 2015 Joe Gross <joe.gross@amd.com> ruby: fix message buffer init order

The recent changes to make MessageBuffers SimObjects required them to be
initialized in a particular order, which could break some protocols. Fix this
by calling initNetQueues on the external nodes of each external link in the
constructor of Network.

This patch also refactors the duplicated code for checking network allocation
and setting net queues (which are called by initNetQueues) from the simple and
garnet networks to be in Network.
11108:6342ddf6d733 Wed Sep 16 00:03:00 EDT 2015 David Hashe <david.hashe@amd.com> ruby: rename System.{hh,cc} to RubySystem.{hh,cc}

The eventual aim of this change is to pass RubySystem pointers through to
objects generated from the SLICC protocol code.

Because some of these objects need to dereference their RubySystem pointers,
they need access to the System.hh header file.

In src/mem/ruby/SConscript, the MakeInclude function creates single-line header
files in the build directory that do nothing except include the corresponding
header file from the source tree.

However, SLICC also generates a list of header files from its symbol table, and
writes it to mem/protocol/Types.hh in the build directory. This code assumes
that the header file name is the same as the class name.

The end result of this is the many of the generated slicc files try to include
RubySystem.hh, when the file they really need is System.hh. The path of least
resistence is just to rename System.hh to RubySystem.hh.
11064:386a5200e298 Sun Aug 30 01:24:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: network: drop member m_in_use

This member indicates whether or not a particular virtual network is in use.
Instead of having a default big value for the number of virtual networks and
then checking whether a virtual network is in use, the next patch removes the
default value and the protocol configuration file would now specify the
number of virtual networks it requires.

Additionally, the patch also refactors some of the code used for computing the
virtual channel next in the round robin order.
11049:dfb0aa3f0649 Wed Aug 19 11:02:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: reverts to changeset: bf82f1f7b040
11047:dcf729f0bbfa Fri Aug 14 20:28:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: simple network: refactor code

Drops an unused variable and marks three variables as const.
11036:3de670f298b1 Fri Aug 14 20:28:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: remove unused functionalRead() function.
11021:e8a6637afa4c Fri Aug 14 01:19:00 EDT 2015 Joel Hestness <jthestness@gmail.com> ruby: Expose MessageBuffers as SimObjects

Expose MessageBuffers from SLICC controllers as SimObjects that can be
manipulated in Python. This patch has numerous benefits:
1) First and foremost, it exposes MessageBuffers as SimObjects that can be
manipulated in Python code. This allows parameters to be set and checked in
Python code to avoid obfuscating parameters within protocol files. Further, now
as SimObjects, MessageBuffer parameters are printed to config output files as a
way to track parameters across simulations (e.g. buffer sizes)

2) Cleans up special-case code for responseFromMemory buffers, and aligns their
instantiation and use with mandatoryQueue buffers. These two special buffers
are the only MessageBuffers that are exposed to components outside of SLICC
controllers, and they're both slave ends of these buffers. They should be
exposed outside of SLICC in the same way, and this patch does it.

3) Distinguishes buffer-specific parameters from buffer-to-network parameters.
Specifically, buffer size, randomization, ordering, recycle latency, and ports
are all specific to a MessageBuffer, while the virtual network ID and type are
intrinsics of how the buffer is connected to network ports. The former are
specified in the Python object, while the latter are specified in the
controller *.sm files. Unlike buffer-specific parameters, which may need to
change depending on the simulated system structure, buffer-to-network
parameters can be specified statically for most or all different simulated
systems.
10917:c38f28fad4c3 Fri Jul 10 17:05:00 EDT 2015 Brandon Potter <brandon.potter@amd.com> ruby: remove extra whitespace and correct misspelled words
H A DSwitch.cc11171:60d4dfa3241a Wed Oct 14 01:29:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: remove unused functionalRead() function.

Not required since functional reads cannot rely on messages that are inflight.
11111:6da33e720481 Wed Sep 16 12:59:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: message buffer, timer table: significant changes

This patch changes MessageBuffer and TimerTable, two structures used for
buffering messages by components in ruby. These structures would no longer
maintain pointers to clock objects. Functions in these structures have been
changed to take as input current time in Tick. Similarly, these structures
will not operate on Cycle valued latencies for different operations. The
corresponding functions would need to be provided with these latencies by
components invoking the relevant functions. These latencies should also be
in Ticks.

I felt the need for these changes while trying to speed up ruby. The ultimate
aim is to eliminate Consumer class and replace it with an EventManager object in
the MessageBuffer and TimerTable classes. This object would be used for
scheduling events. The event itself would contain information on the object and
function to be invoked.

In hindsight, it seems I should have done this while I was moving away from use
of a single global clock in the memory system. That change led to introduction
of clock objects that replaced the global clock object. It never crossed my
mind that having clock object pointers is not a good design. And now I really
don't like the fact that we have separate consumer, receiver and sender
pointers in message buffers.
11049:dfb0aa3f0649 Wed Aug 19 11:02:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: reverts to changeset: bf82f1f7b040
11036:3de670f298b1 Fri Aug 14 20:28:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: remove unused functionalRead() function.
11021:e8a6637afa4c Fri Aug 14 01:19:00 EDT 2015 Joel Hestness <jthestness@gmail.com> ruby: Expose MessageBuffers as SimObjects

Expose MessageBuffers from SLICC controllers as SimObjects that can be
manipulated in Python. This patch has numerous benefits:
1) First and foremost, it exposes MessageBuffers as SimObjects that can be
manipulated in Python code. This allows parameters to be set and checked in
Python code to avoid obfuscating parameters within protocol files. Further, now
as SimObjects, MessageBuffer parameters are printed to config output files as a
way to track parameters across simulations (e.g. buffer sizes)

2) Cleans up special-case code for responseFromMemory buffers, and aligns their
instantiation and use with mandatoryQueue buffers. These two special buffers
are the only MessageBuffers that are exposed to components outside of SLICC
controllers, and they're both slave ends of these buffers. They should be
exposed outside of SLICC in the same way, and this patch does it.

3) Distinguishes buffer-specific parameters from buffer-to-network parameters.
Specifically, buffer size, randomization, ordering, recycle latency, and ports
are all specific to a MessageBuffer, while the virtual network ID and type are
intrinsics of how the buffer is connected to network ports. The former are
specified in the Python object, while the latter are specified in the
controller *.sm files. Unlike buffer-specific parameters, which may need to
change depending on the simulated system structure, buffer-to-network
parameters can be specified statically for most or all different simulated
systems.
10918:dd3ab1f109ad Fri Jul 10 17:05:00 EDT 2015 Brandon Potter <brandon.potter@amd.com> ruby: replace g_ruby_start with per-RubySystem m_start_cycle

This patch begins the process of removing global variables from the Ruby
source with the goal of eventually allowing users to create multiple Ruby
instances in a single simulation. Currently, users cannot do so because
several global variables and static members are referenced by the RubySystem
object in a way that assumes that there will only ever be a single RubySystem.
These need to be replaced with per-RubySystem equivalents.

This specific patch replaces the global var g_ruby_start, which is used
to calculate throughput statistics for Throttles in simple networks and
links in Garnet networks, with a RubySystem instance var m_start_cycle.
/gem5/configs/example/
H A Dmemtest.py11272:744e6074f6ae Thu Dec 17 17:07:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> configs: Make the default memtest behaviour more complex

Add functional and uncacheable accesses by default.
11200:6ef7d715d583 Fri Nov 06 03:26:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> config: Update memtest to stress test clean writebacks

This patch adds yet another twist to the memtest cache hierarchy, in that
the writeback_clean option is toggled at every level to match the
clusivity of the downstream cache.
11198:8149b36b8803 Fri Nov 06 03:26:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> config: Update memtest to stress test cache clusivity

This patch adds an new twist to the memtest cache hierarchy, in that
it switches from mostly inclusive to mostly exclusive at every level
in the tree. This has helped weed out plenty issues, and serves as a
good stress tests.
11053:62544e45c0f4 Fri Aug 21 07:03:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Add explicit Cache subclass and make BaseCache abstract

Open up for other subclasses to BaseCache and transition to using the
explicit Cache subclass.
10887:279efb97ec99 Fri Jul 03 10:14:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Remove redundant is_top_level cache parameter

This patch takes the final step in removing the is_top_level parameter
from the cache. With the recent changes to read requests and write
invalidations, the parameter is no longer needed, and consequently
removed.

This also means that asymmetric cache hierarchies are now fully
supported (and we are actually using them already with L1 caches, but
no table-walker caches, connected to a shared L2).
10750:30efc3828bb4 Thu Mar 19 04:06:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> config: Add soak test for memtest.py

This patch adds a random option to memtest.py which allows the user to
easily test valid random tree topologies. The patch also adds a
wrapper script to run soak tests using the newly introduced option.

We also adjust the progress interval and progress limit check to make
the output less noisy, and avoid false positives.

Bring on the pain.
10720:67b3e74de9ae Mon Mar 02 04:00:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Move crossbar default latencies to subclasses

This patch introduces a few subclasses to the CoherentXBar and
NoncoherentXBar to distinguish the different uses in the system. We
use the crossbar in a wide range of places: interfacing cores to the
L2, as a system interconnect, connecting I/O and peripherals,
etc. Needless to say, these crossbars have very different performance,
and the clock frequency alone is not enough to distinguish these
scenarios.

Instead of trying to capture every possible case, this patch
introduces dedicated subclasses for the three primary use-cases:
L2XBar, SystemXBar and IOXbar. More can be added if needed, and the
defaults can be overridden.
10705:c6cb94a14fea Mon Feb 16 03:35:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> config: Add memcheck stress test

This is a rather unfortunate copy of the memtest.py example script,
that actually stresses the system with true sharing as opposed to the
false sharing of the MemTest. To do so it uses TrafficGen instances to
generate the reads/writes, and MemCheckerMonitor combined with the
MemChecker to check the validity of the read/written values.

As a bonus, this script also enables the addition of prefetchers, and
the traffic is created to have a mix of random addresses and linear
strides. We use the TaggedPrefetcher since the packets do not have a
request with a PC.

At the moment the code is almost identical to the memtest.py script,
and no effort has been made to factor out the construction of the
tree. The challenge is that the instantiation and connection of the
testers and monitors is done as part of the tree building.
10690:4972ada74310 Wed Feb 11 10:23:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> config: Revamp memtest to allow testers on any level

This patch revamps the memtest example script and allows for the
insertion of testers at any level in the cache hierarchy. Previously
all created topologies placed testers only at the very top, and the
tree was thus entirely symmetric. With the changes made, it is possible
to not only place testers at the leaf caches (L1), but also to connect
testers at the L2, L3 etc.

As part of the changes the object hierarchy is also simplified to
ensure that the visual representation from the DOT printing looks
sensible. Using SubSystems to group the objects is one of the key
features.
10688:22452667fd5c Wed Feb 11 10:23:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> cpu: Tidy up the MemTest and make false sharing more obvious

The MemTest class really only tests false sharing, and as such there
was a lot of old cruft that could be removed. This patch cleans up the
tester, and also makes it more clear what the assumptions are. As part
of this simplification the reference functional memory is also
removed.

The regression configs using MemTest are updated to reflect the
changes, and the stats will be bumped in a separate patch. The example
config will be updated in a separate patch due to more extensive
re-work.

In a follow-on patch a new tester will be introduced that uses the
MemChecker to implement true sharing.
/gem5/src/arch/arm/
H A Dtlb.hh11169:44b5c183c3cd Mon Oct 12 04:08:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> misc: Add explicit overrides and fix other clang >= 3.5 issues

This patch adds explicit overrides as this is now required when using
"-Wall" with clang >= 3.5, the latter now part of the most recent
XCode. The patch consequently removes "virtual" for those methods
where "override" is added. The latter should be enough of an
indication.

As part of this patch, a few minor issues that clang >= 3.5 complains
about are also resolved (unused methods and variables).
11168:f98eb2da15a4 Mon Oct 12 04:07:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> misc: Remove redundant compiler-specific defines

This patch moves away from using M5_ATTR_OVERRIDE and the m5::hashmap
(and similar) abstractions, as these are no longer needed with gcc 4.7
and clang 3.1 as minimum compiler versions.
11152:11da02681277 Wed Sep 30 12:14:00 EDT 2015 Mitch Hayenga <mitch.hayenga@arm.com> arm: Change TLB Software Caching

In ARM, certain variables are only updated when a necessary change is
detected. Having 2 SMT threads share a TLB resulted in these not being
updated as required. This patch adds a thread context identifer to
assist in the invalidation of these variables.
10913:38dbdeea7f1f Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Refactor and simplify the drain API

The drain() call currently passes around a DrainManager pointer, which
is now completely pointless since there is only ever one global
DrainManager in the system. It also contains vestiges from the time
when SimObjects had to keep track of their child objects that needed
draining.

This changeset moves all of the DrainState handling to the Drainable
base class and changes the drain() and drainResume() calls to reflect
this. Particularly, the drain() call has been updated to take no
parameters (the DrainManager argument isn't needed) and return a
DrainState instead of an unsigned integer (there is no point returning
anything other than 0 or 1 any more). Drainable objects should return
either DrainState::Draining (equivalent to returning 1 in the old
system) if they need more time to drain or DrainState::Drained
(equivalent to returning 0 in the old system) if they are already in a
consistent state. Returning DrainState::Running is considered an
error.

Drain done signalling is now done through the signalDrainDone() method
in the Drainable class instead of using the DrainManager directly. The
new call checks if the state of the object is DrainState::Draining
before notifying the drain manager. This means that it is safe to call
signalDrainDone() without first checking if the simulator has
requested draining. The intention here is to reduce the code needed to
implement draining in simple objects.
10905:a6ca6831e775 Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Refactor the serialization base class

Objects that are can be serialized are supposed to inherit from the
Serializable class. This class is meant to provide a unified API for
such objects. However, so far it has mainly been used by SimObjects
due to some fundamental design limitations. This changeset redesigns
to the serialization interface to make it more generic and hide the
underlying checkpoint storage. Specifically:

* Add a set of APIs to serialize into a subsection of the current
object. Previously, objects that needed this functionality would
use ad-hoc solutions using nameOut() and section name
generation. In the new world, an object that implements the
interface has the methods serializeSection() and
unserializeSection() that serialize into a named /subsection/ of
the current object. Calling serialize() serializes an object into
the current section.

* Move the name() method from Serializable to SimObject as it is no
longer needed for serialization. The fully qualified section name
is generated by the main serialization code on the fly as objects
serialize sub-objects.

* Add a scoped ScopedCheckpointSection helper class. Some objects
need to serialize data structures, that are not deriving from
Serializable, into subsections. Previously, this was done using
nameOut() and manual section name generation. To simplify this,
this changeset introduces a ScopedCheckpointSection() helper
class. When this class is instantiated, it adds a new /subsection/
and subsequent serialization calls during the lifetime of this
helper class happen inside this section (or a subsection in case
of nested sections).

* The serialize() call is now const which prevents accidental state
manipulation during serialization. Objects that rely on modifying
state can use the serializeOld() call instead. The default
implementation simply calls serialize(). Note: The old-style calls
need to be explicitly called using the
serializeOld()/serializeSectionOld() style APIs. These are used by
default when serializing SimObjects.

* Both the input and output checkpoints now use their own named
types. This hides underlying checkpoint implementation from
objects that need checkpointing and makes it easier to change the
underlying checkpoint storage code.
10873:7c972b9aea16 Sun Jun 21 15:48:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> arm: Cleanup arch headers to remove dma_device.hh dependency

Break the dependency on dma_device.hh by forward-declaring DmaPort in
the relevant header.
10854:f449d6f8a647 Tue May 26 03:21:00 EDT 2015 Nathanael Premillieu <Nathanael.Premillieu@arm.com> arm: Make address translation faster with better caching

This patch adds better caching of the sys regs for AArch64, thus
avoiding unnecessary calls to tc->readMiscReg(MISCREG_CPSR) in the
non-faulting case.
10822:d259f2bc2b31 Tue May 05 03:22:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> arm: Remove unnecessary boot uncachability

With the recent patches addressing how we deal with uncacheable
accesses there is no longer need for the work arounds put in place to
enforce certain sections of memory to be uncacheable during boot.
10717:4f8c1bd6fdb8 Mon Mar 02 04:00:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> arm: Share a port for the two table walker objects

This patch changes how the MMU and table walkers are created such that
a single port is used to connect the MMU and the TLBs to the memory
system. Previously two ports were needed as there are two table walker
objects (stage one and stage two), and they both had a port. Now the
port itself is moved to the Stage2MMU, and each TableWalker is simply
using the port from the parent.

By using the same port we also remove the need for having an
additional crossbar joining the two ports before the walker cache or
the L2. This simplifies the creation of the CPU cache topology in
BaseCPU.py considerably. Moreover, for naming and symmetry reasons,
the TLB walker port is connected through the stage-one table walker
thus making the naming identical to x86. Along the same line, we use
the stage-one table walker to generate the master id that is used by
all TLB-related requests.
10687:276da6265ab8 Wed Feb 11 10:23:00 EST 2015 Andreas Sandberg <Andreas.Sandberg@ARM.com> sim: Move the BaseTLB to src/arch/generic/

The TLB-related code is generally architecture dependent and should
live in the arch directory to signify that.
/gem5/src/mem/slicc/symbols/
H A DType.py11283:4cc8b312f026 Mon Jul 20 10:15:00 EDT 2015 Tony Gutierrez <anthony.gutierrez@amd.com> ruby: slicc: have a static MachineType

This patch is imported from reviewboard patch 2551 by Nilay.
This patch moves from a dynamically defined MachineType to a statically
defined one. The need for this patch was felt since a dynamically defined
type prevents us from having types for which no machine definition may
exist.

The following changes have been made:
i. each machine definition now uses a type from the MachineType enumeration
instead of any random identifier. This required changing the grammar and the
*.sm files.
ii. MachineType enumeration defined statically in RubySlicc_Exports.sm.
* * *
normal protocol fixes for nilay's parser machine type fix
11118:75c1e564a725 Fri Sep 18 14:27:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: print addresses in hex
Changeset 4872dbdea907 replaced Address by Addr, but did not make changes to
print statements. So the addresses which were being printed in hex earlier
along with their line address, were now being printed in decimals. This patch
adds a function printAddress(Addr) that can be used to print the address in hex
along with the lines address. This function has been put to use in some of the
places. At other places, change has been made to print just the address in
hex.
11117:2a1a21f79047 Fri Sep 18 14:27:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: slicc: derive DataMember class from Var instead of PairContainer

The DataMember class in Type.py was being derived from PairContainer. A
separate Var object was also created for the DataMember. This meant some
duplication of across the members of these two classes (Var and DataMember).
This patch changes DataMember from Var instead. There is no obvious reason to
derive from PairContainer which can only hold pairs, something that Var class
already supports. The only thing that DataMember has over Var is init_code,
which is being retained. This change would later on help in having pointers
in DataMembers.
11108:6342ddf6d733 Wed Sep 16 00:03:00 EDT 2015 David Hashe <david.hashe@amd.com> ruby: rename System.{hh,cc} to RubySystem.{hh,cc}

The eventual aim of this change is to pass RubySystem pointers through to
objects generated from the SLICC protocol code.

Because some of these objects need to dereference their RubySystem pointers,
they need access to the System.hh header file.

In src/mem/ruby/SConscript, the MakeInclude function creates single-line header
files in the build directory that do nothing except include the corresponding
header file from the source tree.

However, SLICC also generates a list of header files from its symbol table, and
writes it to mem/protocol/Types.hh in the build directory. This code assumes
that the header file name is the same as the class name.

The end result of this is the many of the generated slicc files try to include
RubySystem.hh, when the file they really need is System.hh. The path of least
resistence is just to rename System.hh to RubySystem.hh.
11089:4808f8c4a47e Tue Sep 08 20:32:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: slicc: remove nextLineHack from Type.py
11025:4872dbdea907 Fri Aug 14 01:04:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: replace Address by Addr
This patch eliminates the type Address defined by the ruby memory system.
This memory system would now use the type Addr that is in use by the
rest of the system.
10920:58fbfddff18d Fri Jul 10 17:05:00 EDT 2015 Brandon Potter <brandon.potter@amd.com> ruby: replace global g_abs_controls with per-RubySystem var

This is another step in the process of removing global variables
from Ruby to enable multiple RubySystem instances in a single simulation.

The list of abstract controllers is per-RubySystem and should be
represented that way, rather than as a global.

Since this is the last remaining Ruby global variable, the
src/mem/ruby/Common/Global.* files are also removed.
10919:80069a602c83 Fri Jul 10 17:05:00 EDT 2015 Brandon Potter <brandon.potter@amd.com> ruby: replace global g_system_ptr with per-object pointers

This is another step in the process of removing global variables
from Ruby to enable multiple RubySystem instances in a single simulation.

With possibly multiple RubySystem objects, we can no longer use a global
variable to find "the" RubySystem object. Instead, each Ruby component
has to carry a pointer to the RubySystem object to which it belongs.
10917:c38f28fad4c3 Fri Jul 10 17:05:00 EDT 2015 Brandon Potter <brandon.potter@amd.com> ruby: remove extra whitespace and correct misspelled words
10895:287285860dd6 Sat Jul 04 11:43:00 EDT 2015 Nilay Vaish <nilay@cs.wisc.edu> ruby: drop NetworkMessage class

This patch drops the NetworkMessage class. The relevant data members and functions
have been moved to the Message class, which was the parent of NetworkMessage.
/gem5/src/mem/cache/
H A Dcache.cc11436:f351b7f248db Wed May 27 08:50:00 EDT 2015 Rekai Gonzalez Alberquilla <Rekai.GonzalezAlberquilla@arm.com> mem: Add unused prefetch counter in caches

Added stat to the cache to account for HardPF'ed blocks that are evicted
before being referenced (over-prefetching).
11288:57c340f947c7 Thu Dec 31 12:32:00 EST 2015 Steve Reinhardt <steve.reinhardt@amd.com> mem: add CacheVerbose debug flag, filter noisy DPRINTFs

Some of the DPRINTFs added to the classic cache in cset 45df88079f04,
while useful to those unfamiliar with the cache code, end up being
noise when you're familiar with the code but are trying to debug tricky
protocol issues. (Particularly getting two messages from each cache
as it receives a snoop request then declares that there was no match.)

This patch introduces a CacheVerbose debug flag, and moves a subset of
the added DPRINTFs into that category, so that Cache by itself returns
to being a more succinct summary of cache activity.

Also added a CacheAll compound flag to turn on all the cache-related
debug flags (other than CacheTags, which you *really* have to want badly
to turn it on, IMO).
11286:2071db8f864b Thu Dec 31 09:33:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Do not allocate space for packet data if not needed

This patch looks at the request and response command to determine if
either actually has any data payload, and if not, we do not allocate
any space for packet data.

The only tricky case is where the command type is changed as part of
the MSHR functionality. In these cases where the original packet had
no data, but the new packet does, we need to explicitly call
allocate().
11285:25715951a4b8 Thu Dec 31 09:33:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Do not alter cache block state on uncacheable snoops

This patch ensures we do not respond with a Modified (dirty and
writable) line if the request is uncacheable, and that the cache
responding retains the line without modifying the state (even if
responding).
11284:b3926db25371 Thu Dec 31 09:32:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Make cache terminology easier to understand

This patch changes the name of a bunch of packet flags and MSHR member
functions and variables to make the coherency protocol easier to
understand. In addition the patch adds and updates lots of
descriptions, explicitly spelling out assumptions.

The following name changes are made:

* the packet memInhibit flag is renamed to cacheResponding

* the packet sharedAsserted flag is renamed to hasSharers

* the packet NeedsExclusive attribute is renamed to NeedsWritable

* the packet isSupplyExclusive is renamed responderHadWritable

* the MSHR pendingDirty is renamed to pendingModified

The cache states, Modified, Owned, Exclusive, Shared are also called
out in the cache and MSHR code to make it easier to understand.
11278:18411ccc4f3c Mon Dec 28 11:14:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Remove unused cache squash functionality

This patch removes the unused squash function from the MSHR queue, and
the associated (and also unused) threadNum member from the MSHR.
11277:4f8703832608 Mon Dec 28 11:14:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Avoid unecessary checks when creating HardPFReq in cache

The checks made before sending out a HardPFReq were unecessarily
complex, and checked for cases that never occur. This patch
tidies it up.
11276:3561d002d8c7 Mon Dec 28 11:14:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Do not use sender state to track forwarded snoops in cache

This patch changes how the cache tracks which snoops are forwarded,
and which ones are created locally. Previously the identification was
based on an empty sender state of a specific class, but this method
fails to distinguish which cache actually attached the sender
state. Instead we use the same mechanism as the crossbar, and keep
track of the requests that have outstanding snoops.
11275:fc2b0e6550ad Mon Dec 28 11:14:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Fix cache sender state handling and add clarification

This patch addresses a bug in how the cache attached the MSHR as a
sender state. Rather than overwriting any existing sender state it now
pushes a new one. The handling of upward snoops is also clarified.
11271:f4ad5be63ba8 Thu Dec 17 17:07:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Fix memory allocation bug in deferred snoop handling

This patch fixes a corner case in the deferred snoop handling, where
requests ended up being used by multiple packets with different
lifetimes, and inadvertently got deleted while they were still in use.
/gem5/src/cpu/testers/traffic_gen/
H A Dtraffic_gen.hh11169:44b5c183c3cd Mon Oct 12 04:08:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> misc: Add explicit overrides and fix other clang >= 3.5 issues

This patch adds explicit overrides as this is now required when using
"-Wall" with clang >= 3.5, the latter now part of the most recent
XCode. The patch consequently removes "virtual" for those methods
where "override" is added. The latter should be enough of an
indication.

As part of this patch, a few minor issues that clang >= 3.5 complains
about are also resolved (unused methods and variables).
11168:f98eb2da15a4 Mon Oct 12 04:07:00 EDT 2015 Andreas Hansson <andreas.hansson@arm.com> misc: Remove redundant compiler-specific defines

This patch moves away from using M5_ATTR_OVERRIDE and the m5::hashmap
(and similar) abstractions, as these are no longer needed with gcc 4.7
and clang 3.1 as minimum compiler versions.
10913:38dbdeea7f1f Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Refactor and simplify the drain API

The drain() call currently passes around a DrainManager pointer, which
is now completely pointless since there is only ever one global
DrainManager in the system. It also contains vestiges from the time
when SimObjects had to keep track of their child objects that needed
draining.

This changeset moves all of the DrainState handling to the Drainable
base class and changes the drain() and drainResume() calls to reflect
this. Particularly, the drain() call has been updated to take no
parameters (the DrainManager argument isn't needed) and return a
DrainState instead of an unsigned integer (there is no point returning
anything other than 0 or 1 any more). Drainable objects should return
either DrainState::Draining (equivalent to returning 1 in the old
system) if they need more time to drain or DrainState::Drained
(equivalent to returning 0 in the old system) if they are already in a
consistent state. Returning DrainState::Running is considered an
error.

Drain done signalling is now done through the signalDrainDone() method
in the Drainable class instead of using the DrainManager directly. The
new call checks if the state of the object is DrainState::Draining
before notifying the drain manager. This means that it is safe to call
signalDrainDone() without first checking if the simulator has
requested draining. The intention here is to reduce the code needed to
implement draining in simple objects.
10905:a6ca6831e775 Tue Jul 07 04:51:00 EDT 2015 Andreas Sandberg <andreas.sandberg@arm.com> sim: Refactor the serialization base class

Objects that are can be serialized are supposed to inherit from the
Serializable class. This class is meant to provide a unified API for
such objects. However, so far it has mainly been used by SimObjects
due to some fundamental design limitations. This changeset redesigns
to the serialization interface to make it more generic and hide the
underlying checkpoint storage. Specifically:

* Add a set of APIs to serialize into a subsection of the current
object. Previously, objects that needed this functionality would
use ad-hoc solutions using nameOut() and section name
generation. In the new world, an object that implements the
interface has the methods serializeSection() and
unserializeSection() that serialize into a named /subsection/ of
the current object. Calling serialize() serializes an object into
the current section.

* Move the name() method from Serializable to SimObject as it is no
longer needed for serialization. The fully qualified section name
is generated by the main serialization code on the fly as objects
serialize sub-objects.

* Add a scoped ScopedCheckpointSection helper class. Some objects
need to serialize data structures, that are not deriving from
Serializable, into subsections. Previously, this was done using
nameOut() and manual section name generation. To simplify this,
this changeset introduces a ScopedCheckpointSection() helper
class. When this class is instantiated, it adds a new /subsection/
and subsequent serialization calls during the lifetime of this
helper class happen inside this section (or a subsection in case
of nested sections).

* The serialize() call is now const which prevents accidental state
manipulation during serialization. Objects that rely on modifying
state can use the serializeOld() call instead. The default
implementation simply calls serialize(). Note: The old-style calls
need to be explicitly called using the
serializeOld()/serializeSectionOld() style APIs. These are used by
default when serializing SimObjects.

* Both the input and output checkpoints now use their own named
types. This hides underlying checkpoint implementation from
objects that need checkpointing and makes it easier to change the
underlying checkpoint storage code.
10713:eddb533708cb Mon Mar 02 04:00:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> mem: Split port retry for all different packet classes

This patch fixes a long-standing isue with the port flow
control. Before this patch the retry mechanism was shared between all
different packet classes. As a result, a snoop response could get
stuck behind a request waiting for a retry, even if the send/recv
functions were split. This caused message-dependent deadlocks in
stress-test scenarios.

The patch splits the retry into one per packet (message) class. Thus,
sendTimingReq has a corresponding recvReqRetry, sendTimingResp has
recvRespRetry etc. Most of the changes to the code involve simply
clarifying what type of request a specific object was accepting.

The biggest change in functionality is in the cache downstream packet
queue, facing the memory. This queue was shared by requests and snoop
responses, and it is now split into two queues, each with their own
flow control, but the same physical MasterPort. These changes fixes
the previously seen deadlocks.
10704:63810213a687 Mon Feb 16 03:34:00 EST 2015 Andreas Hansson <andreas.hansson@arm.com> cpu: TrafficGen sinks snoops without complaining

To be able to use the TrafficGen in a system with caches we need to
allow it to sink incoming snoop requests. By default the master port
panics, so silently ignore any snoops.

Completed in 235 milliseconds

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