diff --git a/Kernel/arch/x86/proc.c b/Kernel/arch/x86/proc.c
index 69c89b279ee058b896dbf8759e76423c33bee9ec..6d84f014ab6c5ebe0e27f0db2e6dd6b856004295 100644
--- a/Kernel/arch/x86/proc.c
+++ b/Kernel/arch/x86/proc.c
@@ -468,7 +468,7 @@ void Proc_Start(void)
{
gpIdleThread = Proc_GetCurThread();
gpIdleThread->ThreadName = "Idle Thread";
- gpIdleThread->NumTickets = 0; // Never called randomly
+ Threads_SetPriority( gpIdleThread, -1 ); // Never called randomly
gpIdleThread->Quantum = 1; // 1 slice quantum
for(;;) HALT(); // Just yeilds
}
diff --git a/Kernel/include/threads.h b/Kernel/include/threads.h
index 20d21f4fbe0e555fbd5d1fee2cc2ee71d1cc3d05..0af38a510dfbed1f54be9c31e5456d34d44da01d 100644
--- a/Kernel/include/threads.h
+++ b/Kernel/include/threads.h
@@ -60,7 +60,7 @@ typedef struct sThread
tMsg *LastMessage; //!< Last Message (speeds up insertion)
int Quantum, Remaining; //!< Quantum Size and remaining timesteps
- int NumTickets; //!< Priority - Chance of gaining CPU
+ int Priority; //!< Priority - 0: Realtime, higher means less time
Uint Config[NUM_CFG_ENTRIES]; //!< Per-process configuration
@@ -97,7 +97,7 @@ extern BOOL gaThreads_NoTaskSwitch[MAX_CPUS];
// === FUNCTIONS ===
extern tThread *Proc_GetCurThread(void);
extern tThread *Threads_GetThread(Uint TID);
-extern void Threads_SetTickets(tThread *Thread, int Num);
+extern void Threads_SetPriority(tThread *Thread, int Pri);
extern int Threads_Wake(tThread *Thread);
extern void Threads_AddActive(tThread *Thread);
extern tThread *Threads_GetNextToRun(int CPU, tThread *Last);
diff --git a/Kernel/threads.c b/Kernel/threads.c
index b9d59f3f00c14644f2678b4bcede04a43c614837..feae49a07087a210d45274d0d6b98f5a2c6ecfce 100644
--- a/Kernel/threads.c
+++ b/Kernel/threads.c
@@ -7,13 +7,22 @@
#include <threads.h>
#include <errno.h>
+// Configuration
#define DEBUG_TRACE_TICKETS 0 // Trace ticket counts
#define DEBUG_TRACE_STATE 0 // Trace state changes (sleep/wake)
+// --- Schedulers ---
+#define SCHED_UNDEF 0
+#define SCHED_LOTTERY 1 // Lottery scheduler
+#define SCHED_RR_SIM 2 // Single Queue Round Robin
+#define SCHED_RR_PRI 3 // Multi Queue Round Robin
+// Set scheduler type
+#define SCHEDULER_TYPE SCHED_RR_PRI
+
// === CONSTANTS ===
#define DEFAULT_QUANTUM 10
-#define DEFAULT_TICKETS 5
-#define MAX_TICKETS 10
+#define DEFAULT_PRIORITY 5
+#define MIN_PRIORITY 10
const enum eConfigTypes cCONFIG_TYPES[] = {
CFGT_HEAPSTR, // e.g. CFG_VFS_CWD
CFGT_INT, // e.g. CFG_VFS_MAXFILES
@@ -64,22 +73,32 @@ tThread gThreadZero = {
ThreadName: "ThreadZero", // Name
Quantum: DEFAULT_QUANTUM, // Default Quantum
Remaining: DEFAULT_QUANTUM, // Current Quantum
- NumTickets: DEFAULT_TICKETS // Number of tickets
+ Priority: DEFAULT_PRIORITY // Number of tickets
};
// -- Processes --
// --- Locks ---
tShortSpinlock glThreadListLock; ///\note NEVER use a heap function while locked
// --- Current State ---
volatile int giNumActiveThreads = 0; // Number of threads on the active queue
-volatile int giFreeTickets = 0; // Number of tickets held by non-scheduled threads
volatile Uint giNextTID = 1; // Next TID to allocate
// --- Thread Lists ---
tThread *gAllThreads = NULL; // All allocated threads
-tThread *gActiveThreads = NULL; // Currently Running Threads
tThread *gSleepingThreads = NULL; // Sleeping Threads
tThread *gDeleteThreads = NULL; // Threads to delete
int giNumCPUs = 1; // Number of CPUs
BOOL gaThreads_NoTaskSwitch[MAX_CPUS]; // Disables task switches for each core (Pseudo-IF)
+// --- Scheduler Types ---
+#if SCHEDULER_TYPE == SCHED_LOTTERY
+const int caiTICKET_COUNTS[MIN_PRIORITY+1] = {100,81,64,49,36,25,16,9,4,1,0};
+volatile int giFreeTickets = 0; // Number of tickets held by non-scheduled threads
+tThread *gActiveThreads = NULL; // Currently Running Threads
+#elif SCHEDULER_TYPE == SCHED_RR_SIM
+tThread *gActiveThreads = NULL; // Currently Running Threads
+#elif SCHEDULER_TYPE == SCHED_RR_PRI
+tThread *gaActiveThreads[MIN_PRIORITY+1]; // Active threads for each priority level
+#else
+# error "Unkown scheduler type"
+#endif
// === CODE ===
/**
@@ -91,9 +110,13 @@ void Threads_Init(void)
ArchThreads_Init();
// Create Initial Task
+ #if SCHEDULER_TYPE == SCHED_RR_PRI
+ gaActiveThreads[gThreadZero.Priority] = &gThreadZero;
+ #else
gActiveThreads = &gThreadZero;
+ #endif
+
gAllThreads = &gThreadZero;
- //giFreeTickets = gThreadZero.NumTickets; // Not needed, as ThreadZero is scheduled
giNumActiveThreads = 1;
Proc_Start();
@@ -137,31 +160,50 @@ char *Threads_GetName(tTID ID)
}
/**
- * \fn void Threads_SetTickets(tThread *Thread, int Num)
- * \brief Sets the 'priority' of a task
+ * \fn void Threads_SetPriority(tThread *Thread, int Pri)
+ * \brief Sets the priority of a task
* \param Thread Thread to update ticket count (NULL means current thread)
- * \param Num New ticket count (must be >= 0, clipped to \a MAX_TICKETS)
+ * \param Pri New priority
*/
-void Threads_SetTickets(tThread *Thread, int Num)
+void Threads_SetPriority(tThread *Thread, int Pri)
{
// Get current thread
if(Thread == NULL) Thread = Proc_GetCurThread();
// Bounds checking
- if(Num < 0) return;
- if(Num > MAX_TICKETS) Num = MAX_TICKETS;
+ // - If < 0, set to lowest priority
+ if(Pri < 0) Pri = MIN_PRIORITY;
+ if(Pri > MIN_PRIORITY) Pri = MIN_PRIORITY;
+
+ // Do we actually have to do anything?
+ if( Pri == Thread->Priority ) return;
+ #if SCHEDULER_TYPE == SCHED_RR_PRI
+ SHORTLOCK( &glThreadListLock );
+ // Remove from old priority
+ Threads_int_DelFromQueue( &gaActiveThreads[Thread->Priority], Thread );
+ // And add to new
+ Thread->Next = gaActiveThreads[Pri];
+ gaActiveThreads[Pri] = Thread;
+ Thread->Priority = Pri;
+ SHORTREL( &glThreadListLock );
+ #else
// If this isn't the current thread, we need to lock
- if( Thread != Proc_GetCurThread() ) {
+ if( Thread != Proc_GetCurThread() )
+ {
SHORTLOCK( &glThreadListLock );
- giFreeTickets -= Thread->NumTickets - Num;
- Thread->NumTickets = Num;
- #if DEBUG_TRACE_TICKETS
+
+ #if SCHEDULER_TYPE == SCHED_LOTTERY
+ giFreeTickets -= caiTICKET_COUNTS[Thread->Priority] - caiTICKET_COUNTS[Pri];
+ # if DEBUG_TRACE_TICKETS
Log("Threads_SetTickets: new giFreeTickets = %i", giFreeTickets);
+ # endif
#endif
+ Thread->Priority = Pri;
SHORTREL( &glThreadListLock );
}
else
- Thread->NumTickets = Num;
+ Thread->Priority = Pri;
+ #endif
}
/**
@@ -209,7 +251,7 @@ tThread *Threads_CloneTCB(Uint *Err, Uint Flags)
// Set State
new->Remaining = new->Quantum = cur->Quantum;
- new->NumTickets = cur->NumTickets;
+ new->Priority = cur->Priority;
// Set Signal Handlers
new->CurFaultNum = 0;
@@ -453,7 +495,11 @@ void Threads_Kill(tThread *Thread, int Status)
SHORTLOCK( &glThreadListLock );
// Delete from active list
+ #if SCHEDULER_TYPE == SCHED_RR_PRI
+ if( !Threads_int_DelFromQueue( &gaActiveThreads[Thread->Priority], Thread ) )
+ #else
if( !Threads_int_DelFromQueue( &gActiveThreads, Thread ) )
+ #endif
{
Warning("Proc_Exit - Current thread is not on the active queue");
SHORTREL( &glThreadListLock );
@@ -467,8 +513,10 @@ void Threads_Kill(tThread *Thread, int Status)
// Update bookkeeping
giNumActiveThreads --;
+ #if SCHEDULER_TYPE == SCHED_LOTTERY
if( Thread != Proc_GetCurThread() )
- giFreeTickets -= Thread->NumTickets;
+ giFreeTickets -= caiTICKET_COUNTS[ Thread->Priority ];
+ #endif
// Save exit status
Thread->RetStatus = Status;
@@ -614,39 +662,29 @@ void Threads_AddActive(tThread *Thread)
{
SHORTLOCK( &glThreadListLock );
- #if 1
- {
- tThread *t;
- for( t = gActiveThreads; t; t = t->Next )
- {
- if( t == Thread ) {
- Panic("Threads_AddActive: Attempting a double add of TID %i (0x%x)",
- Thread->TID, __builtin_return_address(0));
- }
-
- if(t->Status != THREAD_STAT_ACTIVE) {
- Panic("Threads_AddActive: TID %i status != THREAD_STAT_ACTIVE",
- Thread->TID);
- }
- }
- }
- #endif
-
// Set state
Thread->Status = THREAD_STAT_ACTIVE;
Thread->CurCPU = -1;
// Add to active list
+ #if SCHEDULER_TYPE == SCHED_RR_PRI
+ Thread->Next = gaActiveThreads[Thread->Priority];
+ gaActiveThreads[Thread->Priority] = Thread;
+ #else
Thread->Next = gActiveThreads;
gActiveThreads = Thread;
+ #endif
// Update bookkeeping
giNumActiveThreads ++;
- giFreeTickets += Thread->NumTickets;
- #if DEBUG_TRACE_TICKETS
+ #if SCHEDULER_TYPE == SCHED_LOTTERY
+ giFreeTickets += caiTICKET_COUNTS[ Thread->Priority ];
+ # if DEBUG_TRACE_TICKETS
Log("Threads_AddActive: %p %i (%s) added, new giFreeTickets = %i",
Thread, Thread->TID, Thread->ThreadName, giFreeTickets);
+ # endif
#endif
+
SHORTREL( &glThreadListLock );
}
@@ -662,7 +700,12 @@ tThread *Threads_RemActive(void)
SHORTLOCK( &glThreadListLock );
// Delete from active queue
- if( !Threads_int_DelFromQueue(&gActiveThreads, ret) ) {
+ #if SCHEDULER_TYPE == SCHED_RR_PRI
+ if( !Threads_int_DelFromQueue(&gaActiveThreads[ret->Priority], ret) )
+ #else
+ if( !Threads_int_DelFromQueue(&gActiveThreads, ret) )
+ #endif
+ {
SHORTREL( &glThreadListLock );
return NULL;
}
@@ -673,7 +716,7 @@ tThread *Threads_RemActive(void)
giNumActiveThreads --;
// no need to decrement tickets, scheduler did it for us
- #if DEBUG_TRACE_TICKETS
+ #if SCHEDULER_TYPE == SCHED_LOTTERY && DEBUG_TRACE_TICKETS
Log("Threads_RemActive: %p %i (%s) removed, giFreeTickets = %i",
ret, ret->TID, ret->ThreadName, giFreeTickets);
#endif
@@ -774,49 +817,55 @@ int Threads_SetGID(Uint *Errno, tGID ID)
/**
* \fn void Threads_Dump(void)
- * \brief Dumps a list of currently running threads
*/
-void Threads_Dump(void)
+void Threads_DumpActive(void)
{
tThread *thread;
+ #if SCHEDULER_TYPE == SCHED_RR_PRI
+ int i;
+ #endif
- Log("--- Thread Dump ---");
Log("Active Threads: (%i reported)", giNumActiveThreads);
- for(thread=gActiveThreads;thread;thread=thread->Next)
- {
- Log(" %i (%i) - %s (CPU %i)",
- thread->TID, thread->TGID, thread->ThreadName, thread->CurCPU);
- if(thread->Status != THREAD_STAT_ACTIVE)
- Log(" ERROR State (%i) != THREAD_STAT_ACTIVE (%i)", thread->Status, THREAD_STAT_ACTIVE);
- Log(" %i Tickets, Quantum %i", thread->NumTickets, thread->Quantum);
- Log(" KStack 0x%x", thread->KernelStack);
- }
- Log("All Threads:");
- for(thread=gAllThreads;thread;thread=thread->GlobalNext)
+ #if SCHEDULER_TYPE == SCHED_RR_PRI
+ for( i = 0; i < MIN_PRIORITY+1; i++ )
{
- Log(" %i (%i) - %s (CPU %i)",
- thread->TID, thread->TGID, thread->ThreadName, thread->CurCPU);
- Log(" State %i", thread->Status);
- Log(" %i Tickets, Quantum %i", thread->NumTickets, thread->Quantum);
- Log(" KStack 0x%x", thread->KernelStack);
+ for(thread=gaActiveThreads[i];thread;thread=thread->Next)
+ #else
+ for(thread=gActiveThreads;thread;thread=thread->Next)
+ #endif
+ {
+ Log(" %i (%i) - %s (CPU %i)",
+ thread->TID, thread->TGID, thread->ThreadName, thread->CurCPU);
+ if(thread->Status != THREAD_STAT_ACTIVE)
+ Log(" ERROR State (%i) != THREAD_STAT_ACTIVE (%i)", thread->Status, THREAD_STAT_ACTIVE);
+ Log(" Priority %i, Quantum %i", thread->Priority, thread->Quantum);
+ Log(" KStack 0x%x", thread->KernelStack);
+ }
+
+ #if SCHEDULER_TYPE == SCHED_RR_PRI
}
+ #endif
}
+
/**
* \fn void Threads_Dump(void)
+ * \brief Dumps a list of currently running threads
*/
-void Threads_DumpActive(void)
+void Threads_Dump(void)
{
tThread *thread;
- Log("Active Threads:");
- for(thread=gActiveThreads;thread;thread=thread->Next)
+ Log("--- Thread Dump ---");
+ Threads_DumpActive();
+
+ Log("All Threads:");
+ for(thread=gAllThreads;thread;thread=thread->GlobalNext)
{
Log(" %i (%i) - %s (CPU %i)",
thread->TID, thread->TGID, thread->ThreadName, thread->CurCPU);
- if(thread->Status != THREAD_STAT_ACTIVE)
- Log(" ERROR State (%i) != THREAD_STAT_ACTIVE (%i)", thread->Status, THREAD_STAT_ACTIVE);
- Log(" %i Tickets, Quantum %i", thread->NumTickets, thread->Quantum);
+ Log(" State %i", thread->Status);
+ Log(" Priority %i, Quantum %i", thread->Priority, thread->Quantum);
Log(" KStack 0x%x", thread->KernelStack);
}
}
@@ -829,8 +878,6 @@ void Threads_DumpActive(void)
tThread *Threads_GetNextToRun(int CPU, tThread *Last)
{
tThread *thread;
- int ticket;
- int number;
// If this CPU has the lock, we must let it complete
if( CPU_HAS_LOCK( &glThreadListLock ) )
@@ -874,6 +921,7 @@ tThread *Threads_GetNextToRun(int CPU, tThread *Last)
return NULL;
}
+ #if SCHEDULER_TYPE != SCHED_RR_PRI
// Special case: 1 thread
if(giNumActiveThreads == 1) {
if( gActiveThreads->CurCPU == -1 )
@@ -886,17 +934,20 @@ tThread *Threads_GetNextToRun(int CPU, tThread *Last)
return NULL; // CPU has nothing to do
}
+ #endif
// Allow the old thread to be scheduled again
if( Last ) {
if( Last->Status == THREAD_STAT_ACTIVE ) {
- giFreeTickets += Last->NumTickets;
- #if DEBUG_TRACE_TICKETS
+ #if SCHEDULER_TYPE == SCHED_LOTTERY
+ giFreeTickets += caiTICKET_COUNTS[ Last->Priority ];
+ # if DEBUG_TRACE_TICKETS
LogF(" CPU %i released %p (%i %s) into the pool (%i tickets in pool)\n",
CPU, Last, Last->TID, Last->ThreadName, giFreeTickets);
+ # endif
#endif
}
- #if DEBUG_TRACE_TICKETS
+ #if SCHEDULER_TYPE == SCHED_LOTTERY && DEBUG_TRACE_TICKETS
else
LogF(" CPU %i released %p (%i %s)->Status = %i (Released)\n",
CPU, Last, Last->TID, Last->ThreadName, Last->Status);
@@ -904,70 +955,132 @@ tThread *Threads_GetNextToRun(int CPU, tThread *Last)
Last->CurCPU = -1;
}
- #if DEBUG_TRACE_TICKETS
- //Threads_DumpActive();
- #endif
-
- #if 1
- number = 0;
- for(thread = gActiveThreads; thread; thread = thread->Next) {
- if(thread->CurCPU >= 0) continue;
- if(thread->Status != THREAD_STAT_ACTIVE)
- Panic("Bookkeeping fail - %p %i(%s) is on the active queue with a status of %i",
- thread, thread->TID, thread->ThreadName, thread->Status);
- if(thread->Next == thread) {
- Panic("Bookkeeping fail - %p %i(%s) loops back on itself",
- thread, thread->TID, thread->ThreadName, thread->Status);
+ // ---
+ // Lottery Scheduler
+ // ---
+ #if SCHEDULER_TYPE == SCHED_LOTTERY
+ {
+ int ticket, number;
+ # if 1
+ number = 0;
+ for(thread = gActiveThreads; thread; thread = thread->Next) {
+ if(thread->CurCPU >= 0) continue;
+ if(thread->Status != THREAD_STAT_ACTIVE)
+ Panic("Bookkeeping fail - %p %i(%s) is on the active queue with a status of %i",
+ thread, thread->TID, thread->ThreadName, thread->Status);
+ if(thread->Next == thread) {
+ Panic("Bookkeeping fail - %p %i(%s) loops back on itself",
+ thread, thread->TID, thread->ThreadName, thread->Status);
+ }
+ number += caiTICKET_COUNTS[ thread->Priority ];
}
- number += thread->NumTickets;
- }
- if(number != giFreeTickets) {
- Panic("Bookkeeping fail (giFreeTickets(%i) != number(%i)) - CPU%i",
- giFreeTickets, number, CPU);
- }
- #endif
-
- // No free tickets (all tasks delegated to cores)
- if( giFreeTickets == 0 ) {
- SHORTREL(&glThreadListLock);
- return NULL;
+ if(number != giFreeTickets) {
+ Panic("Bookkeeping fail (giFreeTickets(%i) != number(%i)) - CPU%i",
+ giFreeTickets, number, CPU);
+ }
+ # endif
+
+ // No free tickets (all tasks delegated to cores)
+ if( giFreeTickets == 0 ) {
+ SHORTREL(&glThreadListLock);
+ return NULL;
+ }
+
+ // Get the ticket number
+ ticket = number = rand() % giFreeTickets;
+
+ // Find the next thread
+ for(thread=gActiveThreads;thread;thread=thread->Next)
+ {
+ if(thread->CurCPU >= 0) continue;
+ if( caiTICKET_COUNTS[ thread->Priority ] > number) break;
+ number -= caiTICKET_COUNTS[ thread->Priority ];
+ }
+
+ // If we didn't find a thread, something went wrong
+ if(thread == NULL)
+ {
+ number = 0;
+ for(thread=gActiveThreads;thread;thread=thread->Next) {
+ if(thread->CurCPU >= 0) continue;
+ number += caiTICKET_COUNTS[ thread->Priority ];
+ }
+ Panic("Bookeeping Failed - giFreeTickets(%i) > true count (%i)",
+ giFreeTickets, number);
+ }
+ # if DEBUG_TRACE_TICKETS
+ LogF(" CPU%i giFreeTickets = %i, running %p (%i %s CPU=%i)\n",
+ CPU, giFreeTickets, thread, thread->TID, thread->ThreadName, thread->CurCPU);
+ # endif
+
+ giFreeTickets -= caiTICKET_COUNTS[ thread->Priority ];
}
- // Get the ticket number
- ticket = number = rand() % giFreeTickets;
-
- // Find the next thread
- for(thread=gActiveThreads;thread;thread=thread->Next)
+ // ---
+ // Priority based round robin scheduler
+ // ---
+ #elif SCHEDULER_TYPE == SCHED_RR_PRI
{
- if(thread->CurCPU >= 0) continue;
- if(thread->NumTickets > number) break;
- number -= thread->NumTickets;
+ int i;
+ for( i = 0; i < MIN_PRIORITY + 1; i ++ )
+ {
+ for(thread = gaActiveThreads[i]; thread; thread = thread->Next)
+ {
+ if( thread->CurCPU == -1 ) break;
+ }
+ // If we fall onto the same queue again, special handling is
+ // needed
+ if( i == Last->Priority ) {
+ tThread *savedThread = thread;
+
+ // Find the next unscheduled thread in the list
+ for( thread = Last->Next; thread; thread = thread->Next )
+ {
+ if( thread->CurCPU == -1 ) break;
+ }
+ // If we don't find anything after, just use the one
+ // found above.
+ if( !thread ) thread = savedThread;
+ }
+ // Found a thread? Schedule it!
+ if( thread ) break;
+ }
+
+ // Anything to do?
+ if( !thread ) {
+ SHORTREL(&glThreadListLock);
+ return NULL;
+ }
}
- // Error Check
- if(thread == NULL)
- {
- number = 0;
- for(thread=gActiveThreads;thread;thread=thread->Next) {
- if(thread->CurCPU >= 0) continue;
- number += thread->NumTickets;
+ #elif SCHEDULER_TYPE == SCHED_RR_SIM
+ {
+ // Find the next unscheduled thread in the list
+ for( thread = Last->Next; thread; thread = thread->Next )
+ {
+ if( thread->CurCPU == -1 ) break;
+ }
+ // If we don't find anything after, search from the beginning
+ if( !thread )
+ {
+ for(thread = gActiveThreads; thread; thread = thread->Next)
+ {
+ if( thread->CurCPU == -1 ) break;
+ }
+ }
+
+ // Anything to do?
+ if( !thread ) {
+ SHORTREL(&glThreadListLock);
+ return NULL;
}
- Panic("Bookeeping Failed - giFreeTickets(%i) > true count (%i)",
- giFreeTickets, number);
}
- #if DEBUG_TRACE_TICKETS
- LogF(" CPU%i giFreeTickets = %i\n", CPU, giFreeTickets);
+ #else
+ # error "Unimplemented scheduling algorithm"
#endif
// Make the new thread non-schedulable
- giFreeTickets -= thread->NumTickets;
thread->CurCPU = CPU;
- //Threads_Dump();
- #if DEBUG_TRACE_TICKETS
- LogF(" CPU%i giFreeTickets = %i, giving %p (%i %s CPU=%i)\n",
- CPU, giFreeTickets, thread, thread->TID, thread->ThreadName, thread->CurCPU);
- #endif
-
SHORTREL( &glThreadListLock );
return thread;