KThread
class KThread extends KSynchronizationObject, KTimeableInterruptEvent, KSendableInterruptEvent and KSchedulableInterruptEvent;
Size : 0xB0 bytes
| Offset | Type | Description |
|---|---|---|
| 0x0 | u32 | Pointer to vtable |
| 0x4 | u32 | Reference count |
| 0x8 | u32 | Count of KThreads that sync with this object - number of nodes in the linked list below |
| 0xC | KLinkedListNode* | Pointer to first KLinkedListNode in node list of KThreads that sync with this object |
| 0x10 | KLinkedListNode* | Pointer to last KLinkedListNode in node list of KThreads that sync with this object |
| 0x14 | KTimeableInterruptEvent | Used to suspend threads (*this) |
| 0x24 | KSendableInterruptEvent | Interrupt event (*this) sent to terminate a thread, except in the case just below |
| 0x2C | KSchedulableInterruptEvent | Interrupt event (*this) scheduled by the IRQ handler when the thread should terminate (*this) |
| 0x34 | u8 | Scheduling mask |
| 0x35 | u8 | Set to 1 when a thread is woken up from a svcSendSyncRequest call due to the ServerSession endpoint closing down |
| 0x36 | s8 | Indicates that the thread shall terminate |
| 0x37 | u8 | Indicates there was an error translating the parameters in the command buffer during an IPC call |
| 0x38 | KDebugThread* | Pointer to KDebugThread object used with the current KThread |
| 0x3C | u32 | Base thread priority |
| 0x40 | u32 | Pointer to object the KThread is waiting on- can be a timer, event, session, etc. |
| 0x44 | Result | Status for object above |
| 0x48 | KObjectMutex* | Locking kernel mutex |
| 0x4C | u32 | Arbitration address |
| 0x50 | KLinkedListNode* | Pointer to first KLinkedListNode in node list of objects this thread is waiting on |
| 0x54 | KLinkedListNode* | Pointer to last KLinkedListNode in node list of objects this thread is |
| 0x5C | KMutexLinkedList * | Set in some very specific circumstances |
| 0x60 | u32 | Count of KMutex objects this thread is using |
| 0x64 | KLinkedListNode* | Pointer to first KLinkedListNode in node list of KMutex objects this thread is using |
| 0x68 | KLinkedListNode* | Pointer to last KLinkedListNode in node list of KMutex objects this thread is using |
| 0x6C | s32 | Dynamic thread priority |
| 0x70 | s32 | Processor that created the thread (in the sense of "first ran") ; processor the thread is running in |
| 0x74 | KPreemptionTimer * | Points to KResourceLimit+0x60, which among other things holds the amount of CPU time available in ticks, or NULL |
| 0x7C | u8 | Thread is alive |
| 0x7D | u8 | Thread has been terminated |
| 0x7E | u8 | Thread affinity mask - set differently depending on whether the thread is created via svc call or from inside the kernel |
| 0x80 | KProcess* | Process the thread belongs to (virtual address) |
| 0x84 | u32 | Thread id |
| 0x88 | u32* | Ptr to svc mode register storage for KThread inside the thread context. |
| 0x8C | u32* | End-address of the page for this thread context allocated in the 0xFF4XX000 region. Thus, if the beginning of this mapped page is 0xFF401000, this ptr would be 0xFF402000. Thread context page - used for thread svc stack, preserving svc mode registers and VFP exception register for thread. |
| 0x90 | s32 | Ideal processor (processorid value from svcCreateThread) |
| 0x94 | void* | Ptr to Thread Local Storage |
| 0x98 | void* | Ptr to Thread Local Storage in FCRAM via kernel vmem |
| 0xA0 | KThreadLinkedListNode | Previous and next scheduled threads |
| 0xA8 | KThreadLinkedList * | Pointer to linked list of scheduled threads that has stolen it, or 0 if in normal list |
| 0xAC | s32 | Priority field used for priority inheritance when needed |
With the following declarations: struct KThreadLinkedList { KThread *first, *last; }; and struct KThreadLinkedListNode { KThread *prev, *next; };.
Thread Scheduling Mask
The thread scheduling mask is made of a low nibble (enum) and a high nibble (bitfield).
Low nibble:
| Value | Description |
|---|---|
| 0 | The thread is not scheduled |
| 1 | The thread is scheduled |
| 2 | The thread is being terminated |
High nibble:
| Mask | Description |
|---|---|
| 0 | Nothing special |
| 0x8 (bit 3) | The thread has been debug-locked |
A thread is scheduled *if and only if* its (full) scheduling mask is exactly 1. This allows debug-(un)locking of threads to be done transparently.
Thread Affinity Mask
If the thread is created via a call to SVC 8(CreateThread), which uses thread creation type 3, and the CPU ID is -2(meaning use the core specified in the exheader), the mask is just the affinity mask from the thread's owner KProcess. If the CPU ID is -1(meaning any core), the affinity mask is set to 0xF on the New3DS and 0x3 on the Old3DS. Otherwise, the affinity mask is (1 << cpu_id) | 1.
If the thread is created via a call by the kernel, which uses thread creation types 0-2, the checks for -1 and -2 are skipped and the mask is always (1 << cpu_id) | 1.