2 * AcessOS Microkernel Version
17 #define DEBUG_TRACE_SWITCH 0
18 #define DEBUG_DISABLE_DOUBLEFAULT 1
19 #define DEBUG_VERY_SLOW_SWITCH 0
23 #define TIMER_BASE 1193182
24 #if DEBUG_VERY_SLOW_PERIOD
25 # define TIMER_DIVISOR 1193 //~10Hz switch, with 10 quantum = 1s per thread
27 # define TIMER_DIVISOR 11932 //~100Hz
34 Uint8 State; // 0: Unavaliable, 1: Idle, 2: Active
43 extern void APWait(void); // 16-bit AP pause code
44 extern void APStartup(void); // 16-bit AP startup code
45 extern Uint GetEIP(void); // start.asm
46 extern Uint GetEIP_Sched(void); // proc.asm
47 extern void NewTaskHeader(tThread *Thread, void *Fcn, int nArgs, ...); // Actually takes cdecl args
48 extern Uint Proc_CloneInt(Uint *ESP, Uint32 *CR3);
49 extern Uint32 gaInitPageDir[1024]; // start.asm
50 extern char Kernel_Stack_Top[];
53 extern tThread gThreadZero;
54 extern void Isr8(void); // Double Fault
55 extern void Proc_ReturnToUser(tVAddr Handler, Uint Argument, tVAddr KernelStack);
56 extern char scheduler_return[]; // Return address in SchedulerBase
57 extern char IRQCommon[]; // Common IRQ handler code
58 extern char IRQCommon_handled[]; // IRQCommon call return location
59 extern char GetEIP_Sched_ret[]; // GetEIP call return location
60 extern void Threads_AddToDelete(tThread *Thread);
61 extern void SwitchTasks(Uint NewSP, Uint *OldSP, Uint NewIP, Uint *OldIO, Uint CR3);
62 extern void Proc_InitialiseSSE(void);
63 extern void Proc_SaveSSE(Uint DestPtr);
64 extern void Proc_DisableSSE(void);
67 //void ArchThreads_Init(void);
69 void MP_StartAP(int CPU);
70 void MP_SendIPI(Uint8 APICID, int Vector, int DeliveryMode);
72 void Proc_IdleThread(void *Ptr);
73 //void Proc_Start(void);
74 //tThread *Proc_GetCurThread(void);
75 void Proc_ChangeStack(void);
76 // int Proc_NewKThread(void (*Fcn)(void*), void *Data);
77 // int Proc_Clone(Uint *Err, Uint Flags);
78 Uint Proc_MakeUserStack(void);
79 //void Proc_StartUser(Uint Entrypoint, Uint *Bases, int ArgC, char **ArgV, char **EnvP, int DataSize);
80 void Proc_StartProcess(Uint16 SS, Uint Stack, Uint Flags, Uint16 CS, Uint IP) NORETURN;
81 int Proc_Demote(Uint *Err, int Dest, tRegs *Regs);
82 //void Proc_CallFaultHandler(tThread *Thread);
83 //void Proc_DumpThreadCPUState(tThread *Thread);
84 void Proc_Scheduler(int CPU);
87 // --- Multiprocessing ---
89 volatile int giNumInitingCPUs = 0;
90 tMPInfo *gMPFloatPtr = NULL;
91 volatile Uint32 giMP_TimerCount; // Start Count for Local APIC Timer
92 tAPIC *gpMP_LocalAPIC = NULL;
93 Uint8 gaAPIC_to_CPU[256] = {0};
94 int giProc_BootProcessorID = 0;
95 tTSS gaTSSs[MAX_CPUS]; // TSS Array
97 tCPU gaCPUs[MAX_CPUS];
98 tTSS *gTSSs = NULL; // Pointer to TSS array
100 // --- Error Recovery ---
101 char gaDoubleFaultStack[1024] __attribute__ ((section(".padata")));
102 tTSS gDoubleFault_TSS = {
103 .ESP0 = (Uint)&gaDoubleFaultStack[1024],
105 .CR3 = (Uint)gaInitPageDir - KERNEL_BASE,
107 .ESP = (Uint)&gaDoubleFaultStack[1024],
108 .CS = 0x08, .SS = 0x10,
109 .DS = 0x10, .ES = 0x10,
110 .FS = 0x10, .GS = 0x10,
115 * \fn void ArchThreads_Init(void)
116 * \brief Starts the process scheduler
118 void ArchThreads_Init(void)
125 // Mark BSP as active
128 // -- Initialise Multiprocessing
129 // Find MP Floating Table
130 // - EBDA/Last 1Kib (640KiB)
131 for(pos = KERNEL_BASE|0x9F000; pos < (KERNEL_BASE|0xA0000); pos += 16) {
132 if( *(Uint*)(pos) == MPPTR_IDENT ) {
133 Log("Possible %p", pos);
134 if( ByteSum((void*)pos, sizeof(tMPInfo)) != 0 ) continue;
135 gMPFloatPtr = (void*)pos;
139 // - Last KiB (512KiB base mem)
141 for(pos = KERNEL_BASE|0x7F000; pos < (KERNEL_BASE|0x80000); pos += 16) {
142 if( *(Uint*)(pos) == MPPTR_IDENT ) {
143 Log("Possible %p", pos);
144 if( ByteSum((void*)pos, sizeof(tMPInfo)) != 0 ) continue;
145 gMPFloatPtr = (void*)pos;
152 for(pos = KERNEL_BASE|0xE0000; pos < (KERNEL_BASE|0x100000); pos += 16) {
153 if( *(Uint*)(pos) == MPPTR_IDENT ) {
154 Log("Possible %p", pos);
155 if( ByteSum((void*)pos, sizeof(tMPInfo)) != 0 ) continue;
156 gMPFloatPtr = (void*)pos;
162 // If the MP Table Exists, parse it
167 Log("gMPFloatPtr = %p", gMPFloatPtr);
168 Log("*gMPFloatPtr = {");
169 Log("\t.Sig = 0x%08x", gMPFloatPtr->Sig);
170 Log("\t.MPConfig = 0x%08x", gMPFloatPtr->MPConfig);
171 Log("\t.Length = 0x%02x", gMPFloatPtr->Length);
172 Log("\t.Version = 0x%02x", gMPFloatPtr->Version);
173 Log("\t.Checksum = 0x%02x", gMPFloatPtr->Checksum);
174 Log("\t.Features = [0x%02x,0x%02x,0x%02x,0x%02x,0x%02x]",
175 gMPFloatPtr->Features[0], gMPFloatPtr->Features[1],
176 gMPFloatPtr->Features[2], gMPFloatPtr->Features[3],
177 gMPFloatPtr->Features[4]
181 mptable = (void*)( KERNEL_BASE|gMPFloatPtr->MPConfig );
182 Log("mptable = %p", mptable);
184 Log("\t.Sig = 0x%08x", mptable->Sig);
185 Log("\t.BaseTableLength = 0x%04x", mptable->BaseTableLength);
186 Log("\t.SpecRev = 0x%02x", mptable->SpecRev);
187 Log("\t.Checksum = 0x%02x", mptable->Checksum);
188 Log("\t.OEMID = '%8c'", mptable->OemID);
189 Log("\t.ProductID = '%8c'", mptable->ProductID);
190 Log("\t.OEMTablePtr = %p'", mptable->OEMTablePtr);
191 Log("\t.OEMTableSize = 0x%04x", mptable->OEMTableSize);
192 Log("\t.EntryCount = 0x%04x", mptable->EntryCount);
193 Log("\t.LocalAPICMemMap = 0x%08x", mptable->LocalAPICMemMap);
194 Log("\t.ExtendedTableLen = 0x%04x", mptable->ExtendedTableLen);
195 Log("\t.ExtendedTableChecksum = 0x%02x", mptable->ExtendedTableChecksum);
198 gpMP_LocalAPIC = (void*)MM_MapHWPages(mptable->LocalAPICMemMap, 1);
200 ents = mptable->Entries;
203 for( i = 0; i < mptable->EntryCount; i ++ )
210 Log("%i: Processor", i);
211 Log("\t.APICID = %i", ents->Proc.APICID);
212 Log("\t.APICVer = 0x%02x", ents->Proc.APICVer);
213 Log("\t.CPUFlags = 0x%02x", ents->Proc.CPUFlags);
214 Log("\t.CPUSignature = 0x%08x", ents->Proc.CPUSignature);
215 Log("\t.FeatureFlags = 0x%08x", ents->Proc.FeatureFlags);
218 if( !(ents->Proc.CPUFlags & 1) ) {
223 // Check if there is too many processors
224 if(giNumCPUs >= MAX_CPUS) {
225 giNumCPUs ++; // If `giNumCPUs` > MAX_CPUS later, it will be clipped
229 // Initialise CPU Info
230 gaAPIC_to_CPU[ents->Proc.APICID] = giNumCPUs;
231 gaCPUs[giNumCPUs].APICID = ents->Proc.APICID;
232 gaCPUs[giNumCPUs].State = 0;
236 if( ents->Proc.CPUFlags & 2 ) {
237 giProc_BootProcessorID = giNumCPUs-1;
246 Log("\t.ID = %i", ents->Bus.ID);
247 Log("\t.TypeString = '%6C'", ents->Bus.TypeString);
251 Log("%i: I/O APIC", i);
252 Log("\t.ID = %i", ents->IOAPIC.ID);
253 Log("\t.Version = 0x%02x", ents->IOAPIC.Version);
254 Log("\t.Flags = 0x%02x", ents->IOAPIC.Flags);
255 Log("\t.Addr = 0x%08x", ents->IOAPIC.Addr);
257 case 3: // I/O Interrupt Assignment
259 Log("%i: I/O Interrupt Assignment", i);
260 Log("\t.IntType = %i", ents->IOInt.IntType);
261 Log("\t.Flags = 0x%04x", ents->IOInt.Flags);
262 Log("\t.SourceBusID = 0x%02x", ents->IOInt.SourceBusID);
263 Log("\t.SourceBusIRQ = 0x%02x", ents->IOInt.SourceBusIRQ);
264 Log("\t.DestAPICID = 0x%02x", ents->IOInt.DestAPICID);
265 Log("\t.DestAPICIRQ = 0x%02x", ents->IOInt.DestAPICIRQ);
267 case 4: // Local Interrupt Assignment
269 Log("%i: Local Interrupt Assignment", i);
270 Log("\t.IntType = %i", ents->LocalInt.IntType);
271 Log("\t.Flags = 0x%04x", ents->LocalInt.Flags);
272 Log("\t.SourceBusID = 0x%02x", ents->LocalInt.SourceBusID);
273 Log("\t.SourceBusIRQ = 0x%02x", ents->LocalInt.SourceBusIRQ);
274 Log("\t.DestLocalAPICID = 0x%02x", ents->LocalInt.DestLocalAPICID);
275 Log("\t.DestLocalAPICIRQ = 0x%02x", ents->LocalInt.DestLocalAPICIRQ);
278 Log("%i: Unknown (%i)", i, ents->Type);
282 ents = (void*)( (Uint)ents + entSize );
285 if( giNumCPUs > MAX_CPUS ) {
286 Warning("Too many CPUs detected (%i), only using %i of them", giNumCPUs, MAX_CPUS);
287 giNumCPUs = MAX_CPUS;
292 Log("No MP Table was found, assuming uniprocessor\n");
301 #if !DEBUG_DISABLE_DOUBLEFAULT
302 // Initialise Double Fault TSS
303 gGDT[5].BaseLow = (Uint)&gDoubleFault_TSS & 0xFFFF;
304 gGDT[5].BaseMid = (Uint)&gDoubleFault_TSS >> 16;
305 gGDT[5].BaseHi = (Uint)&gDoubleFault_TSS >> 24;
307 // Set double fault IDT to use the new TSS
308 gIDT[8].OffsetLo = 0;
310 gIDT[8].Flags = 0x8500;
311 gIDT[8].OffsetHi = 0;
314 // Set timer frequency
315 outb(0x43, 0x34); // Set Channel 0, Low/High, Rate Generator
316 outb(0x40, TIMER_DIVISOR&0xFF); // Low Byte of Divisor
317 outb(0x40, (TIMER_DIVISOR>>8)&0xFF); // High Byte
319 Log("Timer Frequency %i.%03i Hz",
320 TIMER_BASE/TIMER_DIVISOR,
321 ((Uint64)TIMER_BASE*1000/TIMER_DIVISOR)%1000
325 // Get the count setting for APIC timer
326 Log("Determining APIC Count");
327 __asm__ __volatile__ ("sti");
328 while( giMP_TimerCount == 0 ) __asm__ __volatile__ ("hlt");
329 __asm__ __volatile__ ("cli");
330 Log("APIC Count %i", giMP_TimerCount);
332 Uint64 freq = giMP_TimerCount;
333 freq /= TIMER_DIVISOR;
335 if( (freq /= 1000) < 2*1000)
336 Log("Bus Frequency %i KHz", freq);
337 else if( (freq /= 1000) < 2*1000)
338 Log("Bus Frequency %i MHz", freq);
339 else if( (freq /= 1000) < 2*1000)
340 Log("Bus Frequency %i GHz", freq);
342 Log("Bus Frequency %i THz", freq);
345 // Initialise Normal TSS(s)
346 for(pos=0;pos<giNumCPUs;pos++)
351 gTSSs[pos].SS0 = 0x10;
352 gTSSs[pos].ESP0 = 0; // Set properly by scheduler
353 gGDT[6+pos].BaseLow = ((Uint)(&gTSSs[pos])) & 0xFFFF;
354 gGDT[6+pos].BaseMid = ((Uint)(&gTSSs[pos]) >> 16) & 0xFFFF;
355 gGDT[6+pos].BaseHi = ((Uint)(&gTSSs[pos])) >> 24;
360 // Load the BSP's TSS
361 __asm__ __volatile__ ("ltr %%ax"::"a"(0x30));
362 // Set Current Thread and CPU Number in DR0 and DR1
363 __asm__ __volatile__ ("mov %0, %%db0"::"r"(&gThreadZero));
364 __asm__ __volatile__ ("mov %0, %%db1"::"r"(0));
366 gaCPUs[0].Current = &gThreadZero;
367 gThreadZero.CurCPU = 0;
369 gThreadZero.MemState.CR3 = (Uint)gaInitPageDir - KERNEL_BASE;
371 // Create Per-Process Data Block
372 if( !MM_Allocate(MM_PPD_CFG) )
374 Panic("OOM - No space for initial Per-Process Config");
377 // Initialise SSE support
378 Proc_InitialiseSSE();
385 void MP_StartAP(int CPU)
387 Log("Starting AP %i (APIC %i)", CPU, gaCPUs[CPU].APICID);
389 // Set location of AP startup code and mark for a warm restart
390 *(Uint16*)(KERNEL_BASE|0x467) = (Uint)&APWait - (KERNEL_BASE|0xFFFF0);
391 *(Uint16*)(KERNEL_BASE|0x469) = 0xFFFF;
392 outb(0x70, 0x0F); outb(0x71, 0x0A); // Set warm reset flag
393 MP_SendIPI(gaCPUs[CPU].APICID, 0, 5); // Init IPI
396 inb(0x80); inb(0x80); inb(0x80); inb(0x80);
398 // TODO: Use a better address, preferably registered with the MM
399 // - MM_AllocDMA mabye?
401 *(Uint8*)(KERNEL_BASE|0x11000) = 0xEA; // Far JMP
402 *(Uint16*)(KERNEL_BASE|0x11001) = (Uint)&APStartup - (KERNEL_BASE|0xFFFF0); // IP
403 *(Uint16*)(KERNEL_BASE|0x11003) = 0xFFFF; // CS
404 // Send a Startup-IPI to make the CPU execute at 0x11000 (which we
406 MP_SendIPI(gaCPUs[CPU].APICID, 0x11, 6); // StartupIPI
412 * \brief Send an Inter-Processor Interrupt
413 * \param APICID Processor's Local APIC ID
414 * \param Vector Argument of some kind
415 * \param DeliveryMode Type of signal?
417 void MP_SendIPI(Uint8 APICID, int Vector, int DeliveryMode)
422 val = (Uint)APICID << 24;
423 Log("*%p = 0x%08x", &gpMP_LocalAPIC->ICR[1], val);
424 gpMP_LocalAPIC->ICR[1].Val = val;
426 val = ((DeliveryMode & 7) << 8) | (Vector & 0xFF);
427 Log("*%p = 0x%08x", &gpMP_LocalAPIC->ICR[0], val);
428 gpMP_LocalAPIC->ICR[0].Val = val;
432 void Proc_IdleThread(void *Ptr)
435 cpu->IdleThread->ThreadName = strdup("Idle Thread");
436 Threads_SetPriority( cpu->IdleThread, -1 ); // Never called randomly
437 cpu->IdleThread->Quantum = 1; // 1 slice quantum
445 * \fn void Proc_Start(void)
446 * \brief Start process scheduler
448 void Proc_Start(void)
457 for( i = 0; i < giNumCPUs; i ++ )
459 if(i) gaCPUs[i].Current = NULL;
462 tid = Proc_NewKThread(Proc_IdleThread, &gaCPUs[i]);
463 gaCPUs[i].IdleThread = Threads_GetThread(tid);
466 if( i != giProc_BootProcessorID ) {
471 // BSP still should run the current task
472 gaCPUs[0].Current = &gThreadZero;
474 // Start interrupts and wait for APs to come up
475 Log("Waiting for APs to come up\n");
476 __asm__ __volatile__ ("sti");
477 while( giNumInitingCPUs ) __asm__ __volatile__ ("hlt");
480 tid = Proc_NewKThread(Proc_IdleThread, &gaCPUs[0]);
481 gaCPUs[0].IdleThread = Threads_GetThread(tid);
484 gaCPUs[0].Current = &gThreadZero;
486 // while( gaCPUs[0].IdleThread == NULL )
489 // Start Interrupts (and hence scheduler)
490 __asm__ __volatile__("sti");
492 MM_FinishVirtualInit();
496 * \fn tThread *Proc_GetCurThread(void)
497 * \brief Gets the current thread
499 tThread *Proc_GetCurThread(void)
502 return gaCPUs[ GetCPUNum() ].Current;
504 return gaCPUs[ 0 ].Current;
509 * \fn void Proc_ChangeStack(void)
510 * \brief Swaps the current stack for a new one (in the proper stack reigon)
512 void Proc_ChangeStack(void)
516 Uint curBase, newBase;
518 __asm__ __volatile__ ("mov %%esp, %0":"=r"(esp));
519 __asm__ __volatile__ ("mov %%ebp, %0":"=r"(ebp));
524 newBase = MM_NewKStack();
527 Panic("What the?? Unable to allocate space for initial kernel stack");
531 curBase = (Uint)&Kernel_Stack_Top;
533 LOG("curBase = 0x%x, newBase = 0x%x", curBase, newBase);
535 // Get ESP as a used size
537 LOG("memcpy( %p, %p, 0x%x )", (void*)(newBase - esp), (void*)(curBase - esp), esp );
539 memcpy( (void*)(newBase - esp), (void*)(curBase - esp), esp );
540 // Get ESP as an offset in the new stack
543 ebp = newBase - (curBase - ebp);
545 // Repair EBPs & Stack Addresses
546 // Catches arguments also, but may trash stack-address-like values
547 for(tmpEbp = esp; tmpEbp < newBase; tmpEbp += 4)
549 if(oldEsp < *(Uint*)tmpEbp && *(Uint*)tmpEbp < curBase)
550 *(Uint*)tmpEbp += newBase - curBase;
553 Proc_GetCurThread()->KernelStack = newBase;
555 __asm__ __volatile__ ("mov %0, %%esp"::"r"(esp));
556 __asm__ __volatile__ ("mov %0, %%ebp"::"r"(ebp));
559 void Proc_ClearThread(tThread *Thread)
561 if(Thread->SavedState.SSE) {
562 free(Thread->SavedState.SSE);
563 Thread->SavedState.SSE = NULL;
567 int Proc_NewKThread(void (*Fcn)(void*), void *Data)
570 tThread *newThread, *cur;
572 cur = Proc_GetCurThread();
573 newThread = Threads_CloneTCB(0);
574 if(!newThread) return -1;
577 newThread->MemState.CR3 = cur->MemState.CR3;
580 newThread->KernelStack = MM_NewKStack();
582 if(newThread->KernelStack == 0) {
587 esp = newThread->KernelStack;
588 *(Uint*)(esp-=4) = (Uint)Data; // Data (shadowed)
589 *(Uint*)(esp-=4) = 1; // Number of params
590 *(Uint*)(esp-=4) = (Uint)Fcn; // Function to call
591 *(Uint*)(esp-=4) = (Uint)newThread; // Thread ID
593 newThread->SavedState.ESP = esp;
594 newThread->SavedState.EIP = (Uint)&NewTaskHeader;
595 newThread->SavedState.SSE = NULL;
596 Log("New (KThread) %p, esp = %p\n", newThread->SavedState.EIP, newThread->SavedState.ESP);
599 Threads_AddActive(newThread);
601 return newThread->TID;
605 * \fn int Proc_Clone(Uint *Err, Uint Flags)
606 * \brief Clone the current process
608 int Proc_Clone(Uint Flags)
611 tThread *cur = Proc_GetCurThread();
615 if( !(Flags & CLONE_VM) ) {
616 Log_Error("Proc", "Proc_Clone: Don't leave CLONE_VM unset, use Proc_NewKThread instead");
621 newThread = Threads_CloneTCB(Flags);
622 if(!newThread) return -1;
624 newThread->KernelStack = cur->KernelStack;
627 eip = Proc_CloneInt(&newThread->SavedState.ESP, &newThread->MemState.CR3);
632 newThread->SavedState.EIP = eip;
633 newThread->SavedState.SSE = NULL;
634 newThread->SavedState.bSSEModified = 0;
637 if( newThread->MemState.CR3 == 0 ) {
638 Log_Error("Proc", "Proc_Clone: MM_Clone failed");
639 Threads_AddToDelete(newThread);
643 // Add the new thread to the run queue
644 Threads_AddActive(newThread);
645 return newThread->TID;
649 * \fn int Proc_SpawnWorker(void)
650 * \brief Spawns a new worker thread
652 int Proc_SpawnWorker(void (*Fcn)(void*), void *Data)
655 Uint stack_contents[4];
658 new = Threads_CloneThreadZero();
660 Warning("Proc_SpawnWorker - Out of heap space!\n");
664 // Create the stack contents
665 stack_contents[3] = (Uint)Data;
666 stack_contents[2] = 1;
667 stack_contents[1] = (Uint)Fcn;
668 stack_contents[0] = (Uint)new;
670 // Create a new worker stack (in PID0's address space)
671 new->KernelStack = MM_NewWorkerStack(stack_contents, sizeof(stack_contents));
673 // Save core machine state
674 new->SavedState.ESP = new->KernelStack - sizeof(stack_contents);
675 new->SavedState.EIP = (Uint)NewTaskHeader;
676 new->SavedState.SSE = NULL;
677 new->SavedState.bSSEModified = 0;
680 new->Status = THREAD_STAT_PREINIT;
681 Threads_AddActive( new );
687 * \fn Uint Proc_MakeUserStack(void)
688 * \brief Creates a new user stack
690 Uint Proc_MakeUserStack(void)
693 Uint base = USER_STACK_TOP - USER_STACK_SZ;
695 // Check Prospective Space
696 for( i = USER_STACK_SZ >> 12; i--; )
697 if( MM_GetPhysAddr( base + (i<<12) ) != 0 )
700 if(i != -1) return 0;
702 // Allocate Stack - Allocate incrementally to clean up MM_Dump output
703 for( i = 0; i < USER_STACK_SZ/0x1000; i++ )
705 if( !MM_Allocate( base + (i<<12) ) )
707 Warning("OOM: Proc_MakeUserStack");
712 return base + USER_STACK_SZ;
715 void Proc_StartUser(Uint Entrypoint, Uint Base, int ArgC, char **ArgV, int DataSize)
722 // Copy data to the user stack and free original buffer
723 stack = (void*)Proc_MakeUserStack();
724 stack -= DataSize/sizeof(*stack);
725 memcpy( stack, ArgV, DataSize );
728 // Adjust Arguments and environment
731 Uint delta = (Uint)stack - (Uint)ArgV;
732 ArgV = (char**)stack;
733 for( i = 0; ArgV[i]; i++ ) ArgV[i] += delta;
735 for( i = 0; envp[i]; i++ ) envp[i] += delta;
738 // User Mode Segments
739 ss = 0x23; cs = 0x1B;
742 *--stack = (Uint)envp;
743 *--stack = (Uint)ArgV;
744 *--stack = (Uint)ArgC;
747 Proc_StartProcess(ss, (Uint)stack, 0x202, cs, Entrypoint);
750 void Proc_StartProcess(Uint16 SS, Uint Stack, Uint Flags, Uint16 CS, Uint IP)
752 Uint *stack = (void*)Stack;
753 *--stack = SS; //Stack Segment
754 *--stack = Stack; //Stack Pointer
755 *--stack = Flags; //EFLAGS (Resvd (0x2) and IF (0x20))
756 *--stack = CS; //Code Segment
759 *--stack = 0xAAAAAAAA; // eax
760 *--stack = 0xCCCCCCCC; // ecx
761 *--stack = 0xDDDDDDDD; // edx
762 *--stack = 0xBBBBBBBB; // ebx
763 *--stack = 0xD1D1D1D1; // edi
764 *--stack = 0x54545454; // esp - NOT POPED
765 *--stack = 0x51515151; // esi
766 *--stack = 0xB4B4B4B4; // ebp
773 __asm__ __volatile__ (
774 "mov %%eax,%%esp;\n\t" // Set stack pointer
780 "iret;\n\t" : : "a" (stack));
785 * \fn int Proc_Demote(Uint *Err, int Dest, tRegs *Regs)
786 * \brief Demotes a process to a lower permission level
787 * \param Err Pointer to user's errno
788 * \param Dest New Permission Level
789 * \param Regs Pointer to user's register structure
791 int Proc_Demote(Uint *Err, int Dest, tRegs *Regs)
793 int cpl = Regs->cs & 3;
795 if(Dest > 3 || Dest < 0) {
806 // Change the Segment Registers
807 Regs->cs = (((Dest+1)<<4) | Dest) - 8;
808 Regs->ss = ((Dest+1)<<4) | Dest;
809 // Check if the GP Segs are GDT, then change them
810 if(!(Regs->ds & 4)) Regs->ds = ((Dest+1)<<4) | Dest;
811 if(!(Regs->es & 4)) Regs->es = ((Dest+1)<<4) | Dest;
812 if(!(Regs->fs & 4)) Regs->fs = ((Dest+1)<<4) | Dest;
813 if(!(Regs->gs & 4)) Regs->gs = ((Dest+1)<<4) | Dest;
819 * \brief Calls a signal handler in user mode
820 * \note Used for signals
822 void Proc_CallFaultHandler(tThread *Thread)
824 // Rewinds the stack and calls the user function
826 Proc_ReturnToUser( Thread->FaultHandler, Thread->CurFaultNum, Thread->KernelStack );
830 void Proc_DumpThreadCPUState(tThread *Thread)
832 if( Thread->CurCPU > -1 )
834 int maxBacktraceDistance = 6;
838 if( Thread->CurCPU != GetCPUNum() ) {
839 Log(" Currently running");
843 // Backtrace to find the IRQ entrypoint
844 // - This will usually only be called by an IRQ, so this should
846 __asm__ __volatile__ ("mov %%ebp, %0" : "=r" (stack));
847 while( maxBacktraceDistance -- )
852 if( stack[1] == (tVAddr)&IRQCommon_handled ) {
853 regs = (void*)stack[2];
857 stack = (void*)stack[0];
861 Log(" Unable to find IRQ Entry");
865 Log(" at %04x:%08x", regs->cs, regs->eip);
869 tVAddr diffFromScheduler = Thread->SavedState.EIP - (tVAddr)SwitchTasks;
870 tVAddr diffFromClone = Thread->SavedState.EIP - (tVAddr)Proc_CloneInt;
871 tVAddr diffFromSpawn = Thread->SavedState.EIP - (tVAddr)NewTaskHeader;
873 if( diffFromClone > 0 && diffFromClone < 40 ) // When I last checked, .newTask was at .+27
875 Log(" Creating process");
879 if( diffFromSpawn == 0 )
881 Log(" Creating thread");
885 if( diffFromScheduler > 0 && diffFromScheduler < 128 ) // When I last checked, GetEIP was at .+0x30
888 Log(" At %04x:%08x", Thread->SavedState.UserCS, Thread->SavedState.UserEIP);
892 Log(" Just created (unknown %p)", Thread->SavedState.EIP);
895 void Proc_Reschedule(void)
897 tThread *nextthread, *curthread;
898 int cpu = GetCPUNum();
900 // TODO: Wait for the lock?
901 if(IS_LOCKED(&glThreadListLock)) return;
903 curthread = Proc_GetCurThread();
905 nextthread = Threads_GetNextToRun(cpu, curthread);
908 nextthread = gaCPUs[cpu].IdleThread;
909 if(!nextthread || nextthread == curthread)
912 #if DEBUG_TRACE_SWITCH
913 LogF("\nSwitching to task %i, CR3 = 0x%x, EIP = %p, ESP = %p\n",
915 nextthread->MemState.CR3,
916 nextthread->SavedState.EIP,
917 nextthread->SavedState.ESP
922 gaCPUs[cpu].Current = nextthread;
923 gTSSs[cpu].ESP0 = nextthread->KernelStack-4;
924 __asm__ __volatile__("mov %0, %%db0\n\t" : : "r"(nextthread) );
926 // Save FPU/MMX/XMM/SSE state
927 if( curthread->SavedState.SSE )
929 Proc_SaveSSE( ((Uint)curthread->SavedState.SSE + 0xF) & ~0xF );
930 curthread->SavedState.bSSEModified = 0;
935 nextthread->SavedState.ESP, &curthread->SavedState.ESP,
936 nextthread->SavedState.EIP, &curthread->SavedState.EIP,
937 nextthread->MemState.CR3
944 * \fn void Proc_Scheduler(int CPU)
945 * \brief Swap current thread and clears dead threads
947 void Proc_Scheduler(int CPU)
951 // If the spinlock is set, let it complete
952 if(IS_LOCKED(&glThreadListLock)) return;
954 // Get current thread
955 thread = gaCPUs[CPU].Current;
961 // Reduce remaining quantum and continue timeslice if non-zero
962 if( thread->Remaining-- )
964 // Reset quantum for next call
965 thread->Remaining = thread->Quantum;
967 // TODO: Make this more stable somehow
968 __asm__ __volatile__("mov %%ebp, %0" : "=r" (ebp));
969 regs = (tRegs*)(ebp+(2+2)*4); // EBP,Ret + CPU,CurThread
970 thread->SavedState.UserCS = regs->cs;
971 thread->SavedState.UserEIP = regs->eip;
973 if(thread->bInstrTrace) {
974 regs->eflags |= 0x100; // Set TF
975 Log("%p De-scheduled", thread);
978 regs->eflags &= ~0x100; // Clear TF
985 gpMP_LocalAPIC->EOI.Val = 0;
989 __asm__ __volatile__ ("sti");
995 EXPORT(Proc_SpawnWorker);