mem: Remove threadId from memory request class

In general, the ThreadID parameter is unnecessary in the memory system
as the ContextID is what is used for the purposes of locks/wakeups.
Since we allocate sequential ContextIDs for each thread on MT-enabled
CPUs, ThreadID is unnecessary as the CPUs can identify the requesting
thread through sideband info (SenderState / LSQ entries) or ContextID
offset from the base ContextID for a cpu.

This is a re-spin of 20264eb after the revert (bd1c6789) and includes
some fixes of that commit.

2 files changed, 11 insertions, 15 deletions

diff --git a/src/cpu/simple/atomic.cc b/src/cpu/simple/atomic.cc
index f3e14d401..3996b33ca 100644
--- a/src/cpu/simple/atomic.cc
+++ b/src/cpu/simple/atomic.cc
@@ -87,9 +87,9 @@ AtomicSimpleCPU::init()
     BaseSimpleCPU::init();
 
     int cid = threadContexts[0]->contextId();
-    ifetch_req.setThreadContext(cid, 0);
-    data_read_req.setThreadContext(cid, 0);
-    data_write_req.setThreadContext(cid, 0);
+    ifetch_req.setContext(cid);
+    data_read_req.setContext(cid);
+    data_write_req.setContext(cid);
 }
 
 AtomicSimpleCPU::AtomicSimpleCPU(AtomicSimpleCPUParams *p)
@@ -554,9 +554,9 @@ AtomicSimpleCPU::tick()
     if (numThreads > 1) {
         ContextID cid = threadContexts[curThread]->contextId();
 
-        ifetch_req.setThreadContext(cid, curThread);
-        data_read_req.setThreadContext(cid, curThread);
-        data_write_req.setThreadContext(cid, curThread);
+        ifetch_req.setContext(cid);
+        data_read_req.setContext(cid);
+        data_write_req.setContext(cid);
     }
 
     SimpleExecContext& t_info = *threadInfo[curThread];
diff --git a/src/cpu/simple/timing.cc b/src/cpu/simple/timing.cc
index 43f4eb9f4..6b63d894f 100644
--- a/src/cpu/simple/timing.cc
+++ b/src/cpu/simple/timing.cc
@@ -419,7 +419,6 @@ TimingSimpleCPU::initiateMemRead(Addr addr, unsigned size, unsigned flags)
 
     Fault fault;
     const int asid = 0;
-    const ThreadID tid = curThread;
     const Addr pc = thread->instAddr();
     unsigned block_size = cacheLineSize();
     BaseTLB::Mode mode = BaseTLB::Read;
@@ -427,9 +426,8 @@ TimingSimpleCPU::initiateMemRead(Addr addr, unsigned size, unsigned flags)
     if (traceData)
         traceData->setMem(addr, size, flags);
 
-    RequestPtr req  = new Request(asid, addr, size,
-                                  flags, dataMasterId(), pc,
-                                  thread->contextId(), tid);
+    RequestPtr req = new Request(asid, addr, size, flags, dataMasterId(), pc,
+                                 thread->contextId());
 
     req->taskId(taskId());
 
@@ -494,7 +492,6 @@ TimingSimpleCPU::writeMem(uint8_t *data, unsigned size,
 
     uint8_t *newData = new uint8_t[size];
     const int asid = 0;
-    const ThreadID tid = curThread;
     const Addr pc = thread->instAddr();
     unsigned block_size = cacheLineSize();
     BaseTLB::Mode mode = BaseTLB::Write;
@@ -510,9 +507,8 @@ TimingSimpleCPU::writeMem(uint8_t *data, unsigned size,
     if (traceData)
         traceData->setMem(addr, size, flags);
 
-    RequestPtr req = new Request(asid, addr, size,
-                                 flags, dataMasterId(), pc,
-                                 thread->contextId(), tid);
+    RequestPtr req = new Request(asid, addr, size, flags, dataMasterId(), pc,
+                                 thread->contextId());
 
     req->taskId(taskId());
 
@@ -614,7 +610,7 @@ TimingSimpleCPU::fetch()
         _status = BaseSimpleCPU::Running;
         Request *ifetch_req = new Request();
         ifetch_req->taskId(taskId());
-        ifetch_req->setThreadContext(thread->contextId(), curThread);
+        ifetch_req->setContext(thread->contextId());
         setupFetchRequest(ifetch_req);
         DPRINTF(SimpleCPU, "Translating address %#x\n", ifetch_req->getVaddr());
         thread->itb->translateTiming(ifetch_req, thread->getTC(),