cpu: Move invldPid constant from Request to BaseCPU

A more natural home for this constant.

src/arch/arm/linux/system.cc

@@ -241,7 +241,7 @@ LinuxArmSystem::startup()
         for (int i = 0; i < _numContexts; i++) {
             ThreadContext *tc = threadContexts[i];
             uint32_t pid = tc->getCpuPtr()->getPid();
-            if (pid != Request::invldPid) {
+            if (pid != BaseCPU::invldPid) {
                 mapPid(tc, pid);
                 tc->getCpuPtr()->taskId(taskMap[pid]);
             }

src/cpu/base.cc

@@ -127,7 +127,7 @@ BaseCPU::BaseCPU(Params *p, bool is_checker)
     : MemObject(p), instCnt(0), _cpuId(p->cpu_id), _socketId(p->socket_id),
       _instMasterId(p->system->getMasterId(name() + ".inst")),
       _dataMasterId(p->system->getMasterId(name() + ".data")),
-      _taskId(ContextSwitchTaskId::Unknown), _pid(Request::invldPid),
+      _taskId(ContextSwitchTaskId::Unknown), _pid(invldPid),
       _switchedOut(p->switched_out), _cacheLineSize(p->system->cacheLineSize()),
       interrupts(p->interrupts), profileEvent(NULL),
       numThreads(p->numThreads), system(p->system),

src/cpu/base.hh

@@ -263,6 +263,11 @@ class BaseCPU : public MemObject
 
   public:
 
+
+    /** Invalid or unknown Pid. Possible when operating system is not present
+     *  or has not assigned a pid yet */
+    static const uint32_t invldPid = std::numeric_limits<uint32_t>::max();
+
     // Mask to align PCs to MachInst sized boundaries
     static const Addr PCMask = ~((Addr)sizeof(TheISA::MachInst) - 1);
 

src/mem/request.hh

@@ -195,10 +195,6 @@ class Request
     };
     /** @} */
 
-    /** Invalid or unknown Pid. Possible when operating system is not present
-     *  or has not assigned a pid yet */
-    static const uint32_t invldPid = std::numeric_limits<uint32_t>::max();
-
   private:
     typedef uint8_t PrivateFlagsType;
     typedef ::Flags<PrivateFlagsType> PrivateFlags;