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Scheduler Class Reference

#include <scheduler.h>

List of all members.

Public Methods

 Scheduler ()
 ~Scheduler ()
void ReadyToRun (Thread *thread)
Thread * FindNextToRun ()
void Run (Thread *nextThread)
void Print ()

Private Attributes

List * readyList

Constructor & Destructor Documentation

Scheduler::Scheduler (    ) 
 

Definition at line 30 of file scheduler.cc.

References readyList. 

00031 { 
00032     readyList = new List; 
00033 }

Scheduler::~Scheduler (    ) 
 

Definition at line 40 of file scheduler.cc.

References readyList. 

00041 { 
00042     delete readyList; 
00043 }

Member Function Documentation

Thread * Scheduler::FindNextToRun (    ) 
 

Definition at line 71 of file scheduler.cc.

References readyList, and List::Remove. 

00072 {
00073     return (Thread *)readyList->Remove();
00074 }

void Scheduler::Print (    ) 
 

Definition at line 143 of file scheduler.cc.

References List::Mapcar, readyList, and VoidFunctionPtr. 

00144 {
00145     printf("Ready list contents:\n");
00146     readyList->Mapcar((VoidFunctionPtr) ThreadPrint);
00147 }

void Scheduler::ReadyToRun (  Thread *    thread ) 
 

Definition at line 54 of file scheduler.cc.

References List::Append, DEBUG, Thread::getName, READY, readyList, and Thread::setStatus. 

00055 {
00056     DEBUG('t', "Putting thread %s on ready list.\n", thread->getName());
00057 
00058     thread->setStatus(READY);
00059     readyList->Append((void *)thread);
00060 }

void Scheduler::Run (  Thread *    nextThread ) 
 

Definition at line 91 of file scheduler.cc.

References Thread::CheckOverflow, DEBUG, Thread::getName, NULL, RUNNING, Thread::setStatus, and SWITCH. 

00092 {
00093     Thread *oldThread = currentThread;
00094     
00095 #ifdef USER_PROGRAM                     // ignore until running user programs 
00096     if (currentThread->space != NULL) { // if this thread is a user program,
00097         currentThread->SaveUserState(); // save the user's CPU registers
00098         currentThread->space->SaveState();
00099     }
00100 #endif
00101     
00102     oldThread->CheckOverflow();             // check if the old thread
00103                                             // had an undetected stack overflow
00104 
00105     currentThread = nextThread;             // switch to the next thread
00106     currentThread->setStatus(RUNNING);      // nextThread is now running
00107     
00108     DEBUG('t', "Switching from thread \"%s\" to thread \"%s\"\n",
00109           oldThread->getName(), nextThread->getName());
00110     
00111     // This is a machine-dependent assembly language routine defined 
00112     // in switch.s.  You may have to think
00113     // a bit to figure out what happens after this, both from the point
00114     // of view of the thread and from the perspective of the "outside world".
00115 
00116     SWITCH(oldThread, nextThread);
00117     
00118     DEBUG('t', "Now in thread \"%s\"\n", currentThread->getName());
00119 
00120     // If the old thread gave up the processor because it was finishing,
00121     // we need to delete its carcass.  Note we cannot delete the thread
00122     // before now (for example, in Thread::Finish()), because up to this
00123     // point, we were still running on the old thread's stack!
00124     if (threadToBeDestroyed != NULL) {
00125         delete threadToBeDestroyed;
00126         threadToBeDestroyed = NULL;
00127     }
00128     
00129 #ifdef USER_PROGRAM
00130     if (currentThread->space != NULL) {         // if there is an address space
00131         currentThread->RestoreUserState();     // to restore, do it.
00132         currentThread->space->RestoreState();
00133     }
00134 #endif
00135 }

Member Data Documentation

List* Scheduler::readyList [private]
 

Definition at line 32 of file scheduler.h.

Referenced by FindNextToRun, Print, ReadyToRun, Scheduler, and ~Scheduler.

The documentation for this class was generated from the following files:
Generated on Mon Feb 10 09:54:58 2003 for nachos by doxygen1.2.14 written by Dimitri van Heesch, © 1997-2002
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