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switch semaphore to arraylist because queue buggy

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This commit is contained in:
Christoph Urlacher
2022-07-16 03:30:41 +02:00
parent 2b92b180f4
commit bf3d807464
2 changed files with 9 additions and 6 deletions
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6
c_os/lib/Semaphore.cc
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@ -11,7 +11,7 @@ void Semaphore::p() {
this->lock.release(); this->lock.release();
} else { } else {
// Block and manage thread in semaphore queue until it's woken up by v() again // Block and manage thread in semaphore queue until it's woken up by v() again
this->waitQueue.enqueue(scheduler.get_active()); this->waitQueue.insert(scheduler.get_active());
this->lock.release(); this->lock.release();
scheduler.block(); // Moves to next thread scheduler.block(); // Moves to next thread
} }
@ -20,9 +20,9 @@ void Semaphore::p() {
void Semaphore::v() { void Semaphore::v() {
this->lock.acquire(); this->lock.acquire();
if (!this->waitQueue.isEmpty()) { if (!this->waitQueue.empty()) {
// Semaphore stays busy and unblocks next thread to work in critical section // Semaphore stays busy and unblocks next thread to work in critical section
Thread* next = (Thread*)this->waitQueue.dequeue(); Thread* next = (Thread*)this->waitQueue.remove_first();
this->lock.release(); this->lock.release();
scheduler.deblock(next); scheduler.deblock(next);
} else { } else {

9
c_os/lib/Semaphore.h
View File

@ -11,8 +11,9 @@
#ifndef __Semaphore_include__ #ifndef __Semaphore_include__
#define __Semaphore_include__ #define __Semaphore_include__
#include "lib/Queue.h" #include "kernel/threads/Thread.h"
#include "lib/SpinLock.h" #include "lib/SpinLock.h"
#include "user/lib/ArrayList.h"
class Semaphore { class Semaphore {
@ -20,14 +21,16 @@ private:
Semaphore(const Semaphore& copy) = delete; // Verhindere Kopieren Semaphore(const Semaphore& copy) = delete; // Verhindere Kopieren
// Queue fuer wartende Threads. // Queue fuer wartende Threads.
Queue waitQueue; ArrayList<Thread*> waitQueue;
SpinLock lock; SpinLock lock;
int counter; int counter;
public: public:
// Konstruktor: Initialisieren des Semaphorzaehlers // Konstruktor: Initialisieren des Semaphorzaehlers
Semaphore(int c) : counter(c) {} Semaphore(int c) : counter(c) {
waitQueue.init();
}
// 'Passieren': Warten auf das Freiwerden eines kritischen Abschnitts. // 'Passieren': Warten auf das Freiwerden eines kritischen Abschnitts.
void p(); void p();