scheduler.h File Reference

#include "copyright.h"
#include "list.h"
#include "thread.h"

Go to the source code of this file.

Classes
class	Scheduler
Defines
#define	SCHED()   siglongjmp(schd_jmp, 1)
Functions
void	SetPreemption ()
void	timerInit ()
void	schedule ()
Variables
sigset_t	timer_mask

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Define Documentation

#define SCHED (   )     siglongjmp(schd_jmp, 1)

Definition at line 19 of file scheduler.h. Referenced by Thread::Sleep(), and Thread::Suspend().

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Function Documentation

void schedule (   )

Definition at line 198 of file scheduler.cc. { Thread *nextThread = 0; // disarm the alarm timer_settime(timer_id, 0, &timer_empty, 0); nextThread = scheduler->FindNextToRun(); if (threadToBeDestroyed != NULL) { currentThread = 0; DEBUG('t', "Purge Thread \"%s\"\n", threadToBeDestroyed->getName()); delete threadToBeDestroyed; threadToBeDestroyed = NULL; } if (nextThread != NULL) { if (currentThread) scheduler->ReadyToRun(currentThread); // set to READY currentThread = nextThread; // switch to the next thread //swap over here if (!currentThread->started) { currentThread->started = 1; currentThread->setStatus(RUNNING); // set to RUNNING DEBUG('t', "^Create^ \"%s\"\n", currentThread->getName()); interrupt->Enable(); timer_settime(timer_id, 0, &timer_value, 0); // use the NachOS switch to get the thread going for the // time and then begin to use the siglongjmp way SWITCH(&bogus_th, currentThread); } else { DEBUG('t', "Sched \"%s\"\n", currentThread->getName()); currentThread->setStatus(RUNNING); // set to RUNNING interrupt->Enable(); timer_settime(timer_id, 0, &timer_value, 0); siglongjmp(currentThread->cbuff, 1); } } else if (currentThread)// only a single thread is left { DEBUG('t', "Only Thread \"%s\"\n", currentThread->getName()); currentThread->setStatus(RUNNING); // set to RUNNING interrupt->Enable(); timer_settime(timer_id, 0, &timer_value, 0); sigprocmask(SIG_UNBLOCK, &timer_mask, 0); siglongjmp(currentThread->cbuff, 1); } else { // we are spinning while something is sleeping interrupt->Enable(); timer_settime(timer_id, 0, &timer_value, 0); } }

void SetPreemption (   )

Definition at line 45 of file scheduler.cc. References preempt. { preempt = true; }

void timerInit (   )

Definition at line 162 of file scheduler.cc. References NSECS_PER_SEC, timer_empty, timer_id, timer_mask, and timer_value. Referenced by main(). { struct sigaction tact; //setup the timer handler and tell it to use an alternative signal stack memset(&tact, 0, sizeof(struct sigaction)); tact.sa_handler = Scheduler::timerIntH; tact.sa_flags = 0; sigemptyset(&tact.sa_mask); sigemptyset(&timer_mask); sigaddset(&timer_mask, SIGALRM); if (sigaction(SIGALRM, &tact, NULL) != 0) printf("Failed to set the alarm handler\n"); timer_create(CLOCK_REALTIME, 0, &timer_id); memset(&timer_value, 0, sizeof(struct itimerspec)); memset(&timer_empty, 0, sizeof(struct itimerspec)); timer_value.it_value.tv_sec = 0; timer_value.it_value.tv_nsec = NSECS_PER_SEC / 15; // 0.0666 sec timer_settime(timer_id, 0, &timer_value, 0); }

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Variable Documentation

sigset_t timer_mask

Definition at line 33 of file scheduler.cc. Referenced by schedule(), Interrupt::SetLevel(), and timerInit().

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