gpu-compute: Init CU object for pipe stages in their ctors

This change updates the constructors of the CU's pipe
stages/memory pipelines to accept a pointer to their
parent CU. Because the CU creates these objects, and
can pass a pointer to itself to these object via their
constructors, this is the safer way to initalize these
classes.

Change-Id: I0b3732ce7c03781ee15332dac7a21c097ad387a4
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/29945
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>

src/gpu-compute/compute_unit.cc

@@ -66,9 +66,14 @@ ComputeUnit::ComputeUnit(const Params *p) : ClockedObject(p),
     numScalarALUs(p->num_scalar_cores),
     vrfToCoalescerBusWidth(p->vrf_to_coalescer_bus_width),
     coalescerToVrfBusWidth(p->coalescer_to_vrf_bus_width),
-    registerManager(p->register_manager), fetchStage(p),
-    scoreboardCheckStage(p), scheduleStage(p, this), execStage(p),
-    globalMemoryPipe(p), localMemoryPipe(p), scalarMemoryPipe(p),
+    registerManager(p->register_manager),
+    fetchStage(p, this),
+    scoreboardCheckStage(p, this),
+    scheduleStage(p, this),
+    execStage(p, this),
+    globalMemoryPipe(p, this),
+    localMemoryPipe(p, this),
+    scalarMemoryPipe(p, this),
     tickEvent([this]{ exec(); }, "Compute unit tick event",
           false, Event::CPU_Tick_Pri),
     cu_id(p->cu_id),
@@ -788,13 +793,11 @@ ComputeUnit::init()
         dispatchList.push_back(std::make_pair(nullptr, EMPTY));
     }
 
-    fetchStage.init(this);
-    scoreboardCheckStage.init(this);
-    scheduleStage.init(this);
-    execStage.init(this);
-    globalMemoryPipe.init(this);
-    localMemoryPipe.init(this);
-    scalarMemoryPipe.init(this);
+    fetchStage.init();
+    scoreboardCheckStage.init();
+    scheduleStage.init();
+    execStage.init();
+    globalMemoryPipe.init();
 
     gmTokenPort.setTokenManager(memPortTokens);
 }

src/gpu-compute/exec_stage.cc

@@ -41,19 +41,19 @@
 #include "gpu-compute/vector_register_file.hh"
 #include "gpu-compute/wavefront.hh"
 
-ExecStage::ExecStage(const ComputeUnitParams *p) : lastTimeInstExecuted(false),
-    thisTimeInstExecuted(false), instrExecuted (false),
-    executionResourcesUsed(0)
+ExecStage::ExecStage(const ComputeUnitParams *p, ComputeUnit *cu)
+    : computeUnit(cu), lastTimeInstExecuted(false),
+      thisTimeInstExecuted(false), instrExecuted (false),
+      executionResourcesUsed(0), _name(cu->name() + ".ExecStage")
+
 {
     numTransActiveIdle = 0;
     idle_dur = 0;
 }
 
 void
-ExecStage::init(ComputeUnit *cu)
+ExecStage::init()
 {
-    computeUnit = cu;
-    _name = computeUnit->name() + ".ExecStage";
     dispatchList = &computeUnit->dispatchList;
     idle_dur = 0;
 }

src/gpu-compute/exec_stage.hh

@@ -69,9 +69,9 @@ enum DISPATCH_STATUS
 class ExecStage
 {
   public:
-    ExecStage(const ComputeUnitParams* params);
+    ExecStage(const ComputeUnitParams* p, ComputeUnit *cu);
     ~ExecStage() { }
-    void init(ComputeUnit *cu);
+    void init();
     void exec();
 
     std::string dispStatusToStr(int j);

src/gpu-compute/fetch_stage.cc

@@ -36,11 +36,12 @@
 #include "gpu-compute/compute_unit.hh"
 #include "gpu-compute/wavefront.hh"
 
-FetchStage::FetchStage(const ComputeUnitParams* p) :
-    numVectorALUs(p->num_SIMDs), computeUnit(nullptr)
+FetchStage::FetchStage(const ComputeUnitParams* p, ComputeUnit *cu)
+    : numVectorALUs(p->num_SIMDs), computeUnit(cu),
+      _name(cu->name() + ".FetchStage")
 {
     for (int j = 0; j < numVectorALUs; ++j) {
-        FetchUnit newFetchUnit(p);
+        FetchUnit newFetchUnit(p, cu);
         _fetchUnit.push_back(newFetchUnit);
     }
 }
@@ -51,14 +52,11 @@ FetchStage::~FetchStage()
 }
 
 void
-FetchStage::init(ComputeUnit *cu)
+FetchStage::init()
 {
-    computeUnit = cu;
-    _name = computeUnit->name() + ".FetchStage";
-
     for (int j = 0; j < numVectorALUs; ++j) {
         _fetchUnit[j].bindWaveList(&computeUnit->wfList[j]);
-        _fetchUnit[j].init(computeUnit);
+        _fetchUnit[j].init();
     }
 }
 

src/gpu-compute/fetch_stage.hh

@@ -51,9 +51,9 @@ class Wavefront;
 class FetchStage
 {
   public:
-    FetchStage(const ComputeUnitParams* params);
+    FetchStage(const ComputeUnitParams* p, ComputeUnit *cu);
     ~FetchStage();
-    void init(ComputeUnit *cu);
+    void init();
     void exec();
     void processFetchReturn(PacketPtr pkt);
     void fetch(PacketPtr pkt, Wavefront *wave);

src/gpu-compute/fetch_unit.cc

@@ -45,9 +45,9 @@
 
 uint32_t FetchUnit::globalFetchUnitID;
 
-FetchUnit::FetchUnit(const ComputeUnitParams* params)
-    : timingSim(true), computeUnit(nullptr), fetchScheduler(params),
-      waveList(nullptr), fetchDepth(params->fetch_depth)
+FetchUnit::FetchUnit(const ComputeUnitParams *p, ComputeUnit *cu)
+    : timingSim(true), computeUnit(cu), fetchScheduler(p),
+      waveList(nullptr), fetchDepth(p->fetch_depth)
 {
 }
 
@@ -58,9 +58,8 @@ FetchUnit::~FetchUnit()
 }
 
 void
-FetchUnit::init(ComputeUnit *cu)
+FetchUnit::init()
 {
-    computeUnit = cu;
     timingSim = computeUnit->shader->timingSim;
     fetchQueue.clear();
     fetchStatusQueue.resize(computeUnit->shader->n_wf);

src/gpu-compute/fetch_unit.hh

@@ -49,9 +49,9 @@ class Wavefront;
 class FetchUnit
 {
   public:
-    FetchUnit(const ComputeUnitParams* params);
+    FetchUnit(const ComputeUnitParams* p, ComputeUnit *cu);
     ~FetchUnit();
-    void init(ComputeUnit *cu);
+    void init();
     void exec();
     void bindWaveList(std::vector<Wavefront*> *list);
     void initiateFetch(Wavefront *wavefront);

src/gpu-compute/global_memory_pipeline.cc

@@ -43,19 +43,19 @@
 #include "gpu-compute/vector_register_file.hh"
 #include "gpu-compute/wavefront.hh"
 
-GlobalMemPipeline::GlobalMemPipeline(const ComputeUnitParams* p) :
-    computeUnit(nullptr), gmQueueSize(p->global_mem_queue_size),
-    maxWaveRequests(p->max_wave_requests), inflightStores(0),
-    inflightLoads(0)
+GlobalMemPipeline::GlobalMemPipeline(const ComputeUnitParams* p,
+                                     ComputeUnit *cu)
+    : computeUnit(cu), _name(cu->name() + ".GlobalMemPipeline"),
+      gmQueueSize(p->global_mem_queue_size),
+      maxWaveRequests(p->max_wave_requests), inflightStores(0),
+      inflightLoads(0)
 {
 }
 
 void
-GlobalMemPipeline::init(ComputeUnit *cu)
+GlobalMemPipeline::init()
 {
-    computeUnit = cu;
     globalMemSize = computeUnit->shader->globalMemSize;
-    _name = computeUnit->name() + ".GlobalMemPipeline";
 }
 
 bool

src/gpu-compute/global_memory_pipeline.hh

@@ -56,8 +56,8 @@ class ComputeUnit;
 class GlobalMemPipeline
 {
   public:
-    GlobalMemPipeline(const ComputeUnitParams *params);
-    void init(ComputeUnit *cu);
+    GlobalMemPipeline(const ComputeUnitParams *p, ComputeUnit *cu);
+    void init();
     void exec();
 
     /**

src/gpu-compute/local_memory_pipeline.cc

@@ -41,18 +41,12 @@
 #include "gpu-compute/vector_register_file.hh"
 #include "gpu-compute/wavefront.hh"
 
-LocalMemPipeline::LocalMemPipeline(const ComputeUnitParams* p) :
-    computeUnit(nullptr), lmQueueSize(p->local_mem_queue_size)
+LocalMemPipeline::LocalMemPipeline(const ComputeUnitParams* p, ComputeUnit *cu)
+    : computeUnit(cu), _name(cu->name() + ".LocalMemPipeline"),
+      lmQueueSize(p->local_mem_queue_size)
 {
 }
 
-void
-LocalMemPipeline::init(ComputeUnit *cu)
-{
-    computeUnit = cu;
-    _name = computeUnit->name() + ".LocalMemPipeline";
-}
-
 void
 LocalMemPipeline::exec()
 {

src/gpu-compute/local_memory_pipeline.hh

@@ -55,8 +55,7 @@ class Wavefront;
 class LocalMemPipeline
 {
   public:
-    LocalMemPipeline(const ComputeUnitParams *params);
-    void init(ComputeUnit *cu);
+    LocalMemPipeline(const ComputeUnitParams *p, ComputeUnit *cu);
     void exec();
     std::queue<GPUDynInstPtr> &getLMRespFIFO() { return lmReturnedRequests; }
 

src/gpu-compute/scalar_memory_pipeline.cc

@@ -43,19 +43,14 @@
 #include "gpu-compute/shader.hh"
 #include "gpu-compute/wavefront.hh"
 
-ScalarMemPipeline::ScalarMemPipeline(const ComputeUnitParams* p) :
-    computeUnit(nullptr), queueSize(p->scalar_mem_queue_size),
-    inflightStores(0), inflightLoads(0)
+ScalarMemPipeline::ScalarMemPipeline(const ComputeUnitParams* p,
+                                     ComputeUnit *cu)
+    : computeUnit(cu), _name(cu->name() + ".ScalarMemPipeline"),
+      queueSize(p->scalar_mem_queue_size),
+      inflightStores(0), inflightLoads(0)
 {
 }
 
-void
-ScalarMemPipeline::init(ComputeUnit *cu)
-{
-    computeUnit = cu;
-    _name = computeUnit->name() + ".ScalarMemPipeline";
-}
-
 void
 ScalarMemPipeline::exec()
 {

src/gpu-compute/scalar_memory_pipeline.hh

@@ -59,8 +59,7 @@ class ComputeUnit;
 class ScalarMemPipeline
 {
   public:
-    ScalarMemPipeline(const ComputeUnitParams *params);
-    void init(ComputeUnit *cu);
+    ScalarMemPipeline(const ComputeUnitParams *p, ComputeUnit *cu);
     void exec();
 
     std::queue<GPUDynInstPtr> &getGMReqFIFO() { return issuedRequests; }

src/gpu-compute/schedule_stage.cc

@@ -44,7 +44,8 @@
 #include "gpu-compute/wavefront.hh"
 
 ScheduleStage::ScheduleStage(const ComputeUnitParams *p, ComputeUnit *cu)
-    : vectorAluRdy(false), scalarAluRdy(false), scalarMemBusRdy(false),
+    : computeUnit(cu), _name(cu->name() + ".ScheduleStage"),
+      vectorAluRdy(false), scalarAluRdy(false), scalarMemBusRdy(false),
       scalarMemIssueRdy(false), glbMemBusRdy(false), glbMemIssueRdy(false),
       locMemBusRdy(false), locMemIssueRdy(false)
 {
@@ -66,10 +67,8 @@ ScheduleStage::~ScheduleStage()
 }
 
 void
-ScheduleStage::init(ComputeUnit *cu)
+ScheduleStage::init()
 {
-    computeUnit = cu;
-    _name = computeUnit->name() + ".ScheduleStage";
 
     fatal_if(scheduler.size() != computeUnit->readyList.size(),
              "Scheduler should have same number of entries as CU's readyList");

src/gpu-compute/schedule_stage.hh

@@ -57,9 +57,9 @@ struct ComputeUnitParams;
 class ScheduleStage
 {
   public:
-    ScheduleStage(const ComputeUnitParams *params, ComputeUnit *cu);
+    ScheduleStage(const ComputeUnitParams *p, ComputeUnit *cu);
     ~ScheduleStage();
-    void init(ComputeUnit *cu);
+    void init();
     void exec();
 
     // Stats related variables and methods

src/gpu-compute/scoreboard_check_stage.cc

@@ -44,7 +44,9 @@
 #include "gpu-compute/wavefront.hh"
 #include "params/ComputeUnit.hh"
 
-ScoreboardCheckStage::ScoreboardCheckStage(const ComputeUnitParams *p)
+ScoreboardCheckStage::ScoreboardCheckStage(const ComputeUnitParams *p,
+                                           ComputeUnit *cu)
+    : computeUnit(cu), _name(cu->name() + ".ScoreboardCheckStage")
 {
 }
 
@@ -54,11 +56,8 @@ ScoreboardCheckStage::~ScoreboardCheckStage()
 }
 
 void
-ScoreboardCheckStage::init(ComputeUnit *cu)
+ScoreboardCheckStage::init()
 {
-    computeUnit = cu;
-    _name = computeUnit->name() + ".ScoreboardCheckStage";
-
     for (int unitId = 0; unitId < computeUnit->numExeUnits(); ++unitId) {
         readyList.push_back(&computeUnit->readyList[unitId]);
     }

src/gpu-compute/scoreboard_check_stage.hh

@@ -70,9 +70,9 @@ class ScoreboardCheckStage
         NRDY_CONDITIONS
     };
 
-    ScoreboardCheckStage(const ComputeUnitParams* params);
+    ScoreboardCheckStage(const ComputeUnitParams* p, ComputeUnit *cu);
     ~ScoreboardCheckStage();
-    void init(ComputeUnit *cu);
+    void init();
     void exec();
 
     // Stats related variables and methods