gem5
v20.1.0.0
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#include <tree_plru_rp.hh>
Classes | |
struct | TreePLRUReplData |
Tree-PLRU-specific implementation of replacement data. More... | |
Public Types | |
typedef TreePLRURPParams | Params |
Convenience typedef. More... | |
Public Types inherited from BaseReplacementPolicy | |
typedef BaseReplacementPolicyParams | Params |
Convenience typedef. More... | |
Public Types inherited from SimObject | |
typedef SimObjectParams | Params |
Public Member Functions | |
TreePLRURP (const Params *p) | |
Construct and initiliaze this replacement policy. More... | |
~TreePLRURP () | |
Destructor. More... | |
void | invalidate (const std::shared_ptr< ReplacementData > &replacement_data) const override |
Invalidate replacement data to set it as the next probable victim. More... | |
void | touch (const std::shared_ptr< ReplacementData > &replacement_data) const override |
Touch an entry to update its replacement data. More... | |
void | reset (const std::shared_ptr< ReplacementData > &replacement_data) const override |
Reset replacement data. More... | |
ReplaceableEntry * | getVictim (const ReplacementCandidates &candidates) const override |
Find replacement victim using TreePLRU bits. More... | |
std::shared_ptr< ReplacementData > | instantiateEntry () override |
Instantiate a replacement data entry. More... | |
Public Member Functions inherited from BaseReplacementPolicy | |
BaseReplacementPolicy (const Params *p) | |
Construct and initiliaze this replacement policy. More... | |
virtual | ~BaseReplacementPolicy () |
Destructor. More... | |
Public Member Functions inherited from SimObject | |
const Params * | params () const |
SimObject (const Params *_params) | |
virtual | ~SimObject () |
virtual const std::string | name () const |
virtual void | init () |
init() is called after all C++ SimObjects have been created and all ports are connected. More... | |
virtual void | loadState (CheckpointIn &cp) |
loadState() is called on each SimObject when restoring from a checkpoint. More... | |
virtual void | initState () |
initState() is called on each SimObject when not restoring from a checkpoint. More... | |
virtual void | regProbePoints () |
Register probe points for this object. More... | |
virtual void | regProbeListeners () |
Register probe listeners for this object. More... | |
ProbeManager * | getProbeManager () |
Get the probe manager for this object. More... | |
virtual Port & | getPort (const std::string &if_name, PortID idx=InvalidPortID) |
Get a port with a given name and index. More... | |
virtual void | startup () |
startup() is the final initialization call before simulation. More... | |
DrainState | drain () override |
Provide a default implementation of the drain interface for objects that don't need draining. More... | |
virtual void | memWriteback () |
Write back dirty buffers to memory using functional writes. More... | |
virtual void | memInvalidate () |
Invalidate the contents of memory buffers. More... | |
void | serialize (CheckpointOut &cp) const override |
Serialize an object. More... | |
void | unserialize (CheckpointIn &cp) override |
Unserialize an object. More... | |
Public Member Functions inherited from EventManager | |
EventQueue * | eventQueue () const |
void | schedule (Event &event, Tick when) |
void | deschedule (Event &event) |
void | reschedule (Event &event, Tick when, bool always=false) |
void | schedule (Event *event, Tick when) |
void | deschedule (Event *event) |
void | reschedule (Event *event, Tick when, bool always=false) |
void | wakeupEventQueue (Tick when=(Tick) -1) |
This function is not needed by the usual gem5 event loop but may be necessary in derived EventQueues which host gem5 on other schedulers. More... | |
void | setCurTick (Tick newVal) |
EventManager (EventManager &em) | |
Event manger manages events in the event queue. More... | |
EventManager (EventManager *em) | |
EventManager (EventQueue *eq) | |
Public Member Functions inherited from Serializable | |
Serializable () | |
virtual | ~Serializable () |
void | serializeSection (CheckpointOut &cp, const char *name) const |
Serialize an object into a new section. More... | |
void | serializeSection (CheckpointOut &cp, const std::string &name) const |
void | unserializeSection (CheckpointIn &cp, const char *name) |
Unserialize an a child object. More... | |
void | unserializeSection (CheckpointIn &cp, const std::string &name) |
Public Member Functions inherited from Drainable | |
DrainState | drainState () const |
Return the current drain state of an object. More... | |
virtual void | notifyFork () |
Notify a child process of a fork. More... | |
Public Member Functions inherited from Stats::Group | |
Group (Group *parent, const char *name=nullptr) | |
Construct a new statistics group. More... | |
virtual | ~Group () |
virtual void | regStats () |
Callback to set stat parameters. More... | |
virtual void | resetStats () |
Callback to reset stats. More... | |
virtual void | preDumpStats () |
Callback before stats are dumped. More... | |
void | addStat (Stats::Info *info) |
Register a stat with this group. More... | |
const std::map< std::string, Group * > & | getStatGroups () const |
Get all child groups associated with this object. More... | |
const std::vector< Info * > & | getStats () const |
Get all stats associated with this object. More... | |
void | addStatGroup (const char *name, Group *block) |
Add a stat block as a child of this block. More... | |
const Info * | resolveStat (std::string name) const |
Resolve a stat by its name within this group. More... | |
Group ()=delete | |
Group (const Group &)=delete | |
Group & | operator= (const Group &)=delete |
Private Types | |
typedef std::vector< bool > | PLRUTree |
Instead of implementing the tree itself with pointers, it is implemented as an array of bits. More... | |
Private Attributes | |
const uint64_t | numLeaves |
Number of leaves that share a single replacement data. More... | |
uint64_t | count |
Count of the number of sharers of a replacement data. More... | |
PLRUTree * | treeInstance |
Holds the latest temporary tree instance created by instantiateEntry(). More... | |
Additional Inherited Members | |
Static Public Member Functions inherited from SimObject | |
static void | serializeAll (CheckpointOut &cp) |
Serialize all SimObjects in the system. More... | |
static SimObject * | find (const char *name) |
Find the SimObject with the given name and return a pointer to it. More... | |
Static Public Member Functions inherited from Serializable | |
static const std::string & | currentSection () |
Gets the fully-qualified name of the active section. More... | |
static void | serializeAll (const std::string &cpt_dir) |
Serializes all the SimObjects. More... | |
static void | unserializeGlobals (CheckpointIn &cp) |
Protected Member Functions inherited from Drainable | |
Drainable () | |
virtual | ~Drainable () |
virtual void | drainResume () |
Resume execution after a successful drain. More... | |
void | signalDrainDone () const |
Signal that an object is drained. More... | |
Protected Attributes inherited from SimObject | |
const SimObjectParams * | _params |
Cached copy of the object parameters. More... | |
Protected Attributes inherited from EventManager | |
EventQueue * | eventq |
A pointer to this object's event queue. More... | |
Definition at line 80 of file tree_plru_rp.hh.
typedef TreePLRURPParams TreePLRURP::Params |
Convenience typedef.
Definition at line 153 of file tree_plru_rp.hh.
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private |
Instead of implementing the tree itself with pointers, it is implemented as an array of bits.
The index of the node defines its position in the tree, and its parent. Index 0 represents the root, 1 is its left node, and 2 is its right node. Then, in a BFS fashion this is expanded to the following nodes (3 and 4 are respectively 1's left and right nodes, and 5 and 6 are 2's left and right nodes, and so on).
i.e., the following trees are equivalent in this representation: ____1____ 0 1 0 1 1 0 A B C D E F G H
1 0 1 0 1 1 0
Notice that the replacement data entries are not represented in the tree to avoid unnecessary storage costs.
Definition at line 102 of file tree_plru_rp.hh.
TreePLRURP::TreePLRURP | ( | const Params * | p | ) |
Construct and initiliaze this replacement policy.
Definition at line 98 of file tree_plru_rp.cc.
References fatal_if, isPowerOf2(), and numLeaves.
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inline |
Destructor.
Definition at line 163 of file tree_plru_rp.hh.
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overridevirtual |
Find replacement victim using TreePLRU bits.
It is assumed that all candidates share the same replacement data tree.
candidates | Replacement candidates, selected by indexing policy. |
Implements BaseReplacementPolicy.
Definition at line 167 of file tree_plru_rp.cc.
References leftSubtreeIndex(), numLeaves, and rightSubtreeIndex().
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overridevirtual |
Instantiate a replacement data entry.
Consecutive calls to this function use the same tree up to numLeaves. When numLeaves replacement data have been created, a new tree is generated, and the counter is reset. Therefore, it is essential that entries that share the same replacement data call this function consecutively.
Implements BaseReplacementPolicy.
Definition at line 195 of file tree_plru_rp.cc.
References count, numLeaves, and treeInstance.
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overridevirtual |
Invalidate replacement data to set it as the next probable victim.
Makes tree leaf of replacement data the LRU (tree bits point to it).
replacement_data | Replacement data to be invalidated. |
Implements BaseReplacementPolicy.
Definition at line 107 of file tree_plru_rp.cc.
References isRightSubtree(), and parentIndex().
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overridevirtual |
Reset replacement data.
Used when an entry is inserted. Provides the same functionality as touch().
replacement_data | Replacement data to be reset. |
Implements BaseReplacementPolicy.
Definition at line 159 of file tree_plru_rp.cc.
References touch().
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overridevirtual |
Touch an entry to update its replacement data.
Makes tree leaf of replacement data the MRU.
replacement_data | Replacement data to be touched. |
Implements BaseReplacementPolicy.
Definition at line 133 of file tree_plru_rp.cc.
References isRightSubtree(), and parentIndex().
Referenced by reset().
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private |
Count of the number of sharers of a replacement data.
It is used when instantiating entries to share a replacement data among many replaceable entries.
Definition at line 114 of file tree_plru_rp.hh.
Referenced by instantiateEntry().
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private |
Number of leaves that share a single replacement data.
Definition at line 107 of file tree_plru_rp.hh.
Referenced by getVictim(), instantiateEntry(), and TreePLRURP().
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private |
Holds the latest temporary tree instance created by instantiateEntry().
Definition at line 119 of file tree_plru_rp.hh.
Referenced by instantiateEntry().