tGID Threads_GetGID(void);
int Threads_SetGID(Uint *Errno, tUID ID);
void Threads_Dump(void);
+void Mutex_Acquire(tMutex *Mutex);
+void Mutex_Release(tMutex *Mutex);
+ int Mutex_IsLocked(tMutex *Mutex);
// === GLOBALS ===
// -- Core Thread --
};
// -- Processes --
// --- Locks ---
-tSpinlock glThreadListLock = 0; ///\note NEVER use a heap function while locked
+tShortSpinlock glThreadListLock; ///\note NEVER use a heap function while locked
// --- Current State ---
volatile int giNumActiveThreads = 0;
//volatile int giTotalTickets = 0;
if(Num > MAX_TICKETS) Num = MAX_TICKETS;
if( Thread != Proc_GetCurThread() ) {
- LOCK( &glThreadListLock );
+ SHORTLOCK( &glThreadListLock );
giFreeTickets -= Thread->NumTickets - Num;
Thread->NumTickets = Num;
- RELEASE( &glThreadListLock );
+ SHORTREL( &glThreadListLock );
}
else
Thread->NumTickets = Num;
new->CurCPU = -1;
new->Next = NULL;
- new->IsLocked = 0;
+ memset( &new->IsLocked, 0, sizeof(new->IsLocked));
new->Status = THREAD_STAT_ACTIVE;
new->RetStatus = 0;
///\note Double lock is needed due to overlap of lock areas
// Lock thread (stop us recieving messages)
- LOCK( &Thread->IsLocked );
+ SHORTLOCK( &Thread->IsLocked );
// Lock thread list
- LOCK( &glThreadListLock );
+ SHORTLOCK( &glThreadListLock );
// Get previous thread on list
prev = Threads_int_GetPrev( &gActiveThreads, Thread );
if(!prev) {
Warning("Proc_Exit - Current thread is not on the active queue");
+ Thread->IsLocked.Lock = 0; // We can't use SHORTREL as that starts IRQs again
+ SHORTREL( &glThreadListLock );
return;
}
}
// Release spinlocks
- RELEASE( &Thread->IsLocked ); // Released first so that it IS released
- RELEASE( &glThreadListLock );
+ Thread->IsLocked.Lock = 0; // Released first so that it IS released
+ SHORTREL( &glThreadListLock );
//Log("Thread %i went *hurk*", Thread->TID);
//Log_Log("Threads", "%i going to sleep", cur->TID);
// Acquire Spinlock
- LOCK( &glThreadListLock );
+ SHORTLOCK( &glThreadListLock );
// Get thread before current thread
thread = Threads_int_GetPrev( &gActiveThreads, cur );
if(!thread) {
Warning("Threads_Sleep - Current thread is not on the active queue");
Threads_Dump();
- RELEASE( &glThreadListLock );
+ SHORTREL( &glThreadListLock );
return;
}
// Don't sleep if there is a message waiting
if( cur->Messages ) {
- RELEASE( &glThreadListLock );
+ SHORTREL( &glThreadListLock );
return;
}
// Reduce the active count & ticket count
giNumActiveThreads --;
+ // - No need to alter giFreeTickets (we're being executed)
// Mark thread as sleeping
cur->Status = THREAD_STAT_SLEEPING;
// Release Spinlock
- RELEASE( &glThreadListLock );
+ SHORTREL( &glThreadListLock );
while(cur->Status != THREAD_STAT_ACTIVE) HALT();
}
case THREAD_STAT_ACTIVE:
Log("Thread_Wake: Waking awake thread (%i)", Thread->TID);
return -EALREADY;
- case THREAD_STAT_SLEEPING:
+ case THREAD_STAT_SLEEPING: // TODO: Comment better
//Log_Log("Threads", "Waking %i (%p) from sleeping (CPU=%i)",
// Thread->TID, Thread, Thread->CurCPU);
- LOCK( &glThreadListLock );
+ SHORTLOCK( &glThreadListLock );
prev = Threads_int_GetPrev(&gSleepingThreads, Thread);
prev->Next = Thread->Next; // Remove from sleeping queue
Thread->Next = gActiveThreads; // Add to active queue
Log("Threads_Wake: giFreeTickets = %i", giFreeTickets);
#endif
Thread->Status = THREAD_STAT_ACTIVE;
- RELEASE( &glThreadListLock );
+ SHORTREL( &glThreadListLock );
return -EOK;
case THREAD_STAT_WAITING:
Warning("Thread_Wake - Waiting threads are not currently supported");
*/
void Threads_AddActive(tThread *Thread)
{
- LOCK( &glThreadListLock );
+ SHORTLOCK( &glThreadListLock );
Thread->Next = gActiveThreads;
gActiveThreads = Thread;
giNumActiveThreads ++;
#if DEBUG_TRACE_TICKETS
Log("Threads_AddActive: giFreeTickets = %i", giFreeTickets);
#endif
- RELEASE( &glThreadListLock );
+ SHORTREL( &glThreadListLock );
}
/**
while(gDeleteThreads)
{
thread = gDeleteThreads->Next;
- if(gDeleteThreads->IsLocked) { // Only free if structure is unused
+ if( IS_LOCKED(&gDeleteThreads->IsLocked) ) { // Only free if structure is unused
gDeleteThreads->Status = THREAD_STAT_NULL;
free( gDeleteThreads );
}
// but it has a potentially long lock period)
// - Well, this CPU can obtain the lock, but that is aliveviated by
// the above.
- TIGHTLOCK( &glThreadListLock );
+ SHORTLOCK( &glThreadListLock );
// Special case: 1 thread
if(giNumActiveThreads == 1) {
if( gActiveThreads->CurCPU == -1 )
gActiveThreads->CurCPU = CPU;
- RELEASE( &glThreadListLock );
+ SHORTREL( &glThreadListLock );
if( gActiveThreads->CurCPU == CPU )
return gActiveThreads;
return NULL; // CPU has nothing to do
// No free tickets (all tasks delegated to cores)
if( giFreeTickets == 0 ) {
- RELEASE(&glThreadListLock);
+ SHORTREL(&glThreadListLock);
return NULL;
}
CPU, giFreeTickets, thread, thread->ThreadName, thread->CurCPU);
#endif
- RELEASE( &glThreadListLock );
+ SHORTREL( &glThreadListLock );
return thread;
}
//Threads_Exit( 0, -1 );
}
+/**
+ * \brief Acquire a heavy mutex
+ * \param Mutex Mutex to acquire
+ *
+ * This type of mutex checks if the mutex is avaliable, and acquires it
+ * if it is. Otherwise, the current thread is added to the mutex's wait
+ * queue and the thread suspends. When the holder of the mutex completes,
+ * the oldest thread (top thread) on the queue is given the lock and
+ * restarted.
+ */
+void Mutex_Acquire(tMutex *Mutex)
+{
+ tThread *us = Proc_GetCurThread();
+ tThread *prev;
+
+ // Get protector
+ SHORTLOCK( &Mutex->Protector );
+
+ //Log("Mutex_Acquire: (%p)", Mutex);
+
+ // Check if the lock is already held
+ if( Mutex->Owner ) {
+ SHORTLOCK( &glThreadListLock );
+ // - Remove from active list
+ us->Remaining = 0;
+ prev = Threads_int_GetPrev(&gActiveThreads, us);
+ prev->Next = us->Next;
+ giNumActiveThreads --;
+ us->Status = THREAD_STAT_SLEEPING;
+
+ // - Add to waiting
+ if(Mutex->LastWaiting) {
+ Mutex->LastWaiting->Next = us;
+ Mutex->LastWaiting = us;
+ }
+ else {
+ Mutex->Waiting = us;
+ Mutex->LastWaiting = us;
+ }
+ SHORTREL( &glThreadListLock );
+ SHORTREL( &Mutex->Protector );
+ while(us->Status == THREAD_STAT_SLEEPING) HALT();
+ // We're only woken when we get the lock
+ }
+ // Ooh, let's take it!
+ else {
+ Mutex->Owner = us;
+ SHORTREL( &Mutex->Protector );
+ }
+}
+
+/**
+ * \brief Release a held mutex
+ * \param Mutex Mutex to release
+ */
+void Mutex_Release(tMutex *Mutex)
+{
+ SHORTLOCK( &Mutex->Protector );
+ //Log("Mutex_Release: (%p)", Mutex);
+ if( Mutex->Waiting ) {
+ Mutex->Owner = Mutex->Waiting; // Set owner
+ Mutex->Waiting = Mutex->Waiting->Next; // Next!
+ // Wake new owner
+ Mutex->Owner->Status = THREAD_STAT_ACTIVE;
+ Threads_AddActive(Mutex->Owner);
+ Log("Mutex %p Woke %p", Mutex, Mutex->Owner);
+ }
+ else {
+ Mutex->Owner = NULL;
+ }
+ SHORTREL( &Mutex->Protector );
+}
+
+/**
+ * \brief Is this mutex locked?
+ * \param Mutex Mutex pointer
+ */
+int Mutex_IsLocked(tMutex *Mutex)
+{
+ return Mutex->Owner != NULL;
+}
+
// === EXPORTS ===
EXPORT(Threads_GetUID);
git.ucc.asn.au / tpg / acess2.git / blobdiff
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