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[[Category:Kernel objects]]
[[Category:Kernel synchronization objects]]
class [[KThread]] extends [[KSynchronizationObject]];
[[Category:Kernel interrupt events]]
class [[KThread]] extends [[KSynchronizationObject]], [[KTimeableInterruptEvent]], [[KSendableInterruptEvent]] and [[KSchedulableInterruptEvent]];


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{| class="wikitable" border="1"
{| class="wikitable" border="1"
|-
|-
! Offset
! Offset
! Type
! Type
! Description
! Description
|-
|-
| 0x0
| 0x0
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| u32
| u32
| Reference count
| 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
| 0x3C
| u32
| u32
| Thread priority
| Base thread priority
|-
|-
| 0x40
| 0x40
| u32
| u32
| Arbitration ???
| Pointer to object the KThread is waiting on- can be a timer, event, session, etc.
|-
| 0x44
| Result
| Status for object above
|-
|-
| 0x48
| 0x48
| u32
| KObjectMutex*
| Arbitration ???
| Locking kernel mutex
|-
|-
| 0x4C
| 0x4C
| u32
| u32
| Arbitration address
| 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
| [[KMutex|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
| 0x6C
| s32
| s32
| Thread priority
| Dynamic thread priority
|-
|-
| 0x70
| 0x70
| s32
| s32
| Processor that created the thread
| Processor that created the thread (in the sense of "first ran") ; processor the thread is running in
|-
| 0x74
| [[KResourceLimit|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
| 0x80
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| 0x88
| 0x88
| u32*
| u32*
| Ptr to svc mode register storage for KThread.
| Ptr to svc mode register storage for KThread inside the thread context.
|-
|-
| 0x8C
| 0x8C
| u32*
| u32*
| End-address of the page for this thread allocated in the [[Memory_layout|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.
| End-address of the page for this thread context allocated in the [[Memory_layout|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
| 0x90
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| 0x94
| 0x94
| void*
| void*
| Ptr to threadlocalstorage
| Ptr to [[Thread Local Storage]]
|-
|-
| 0x98
| 0x98
| void*
| void*
| Ptr to threadlocalstorage in FCRAM via kernel vmem
| Ptr to [[Thread Local Storage]] in FCRAM via kernel vmem
|-
|-
| 0xA0
| 0xA0
| KThread*
| KThreadLinkedListNode
| Previous (virtual address)
| 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 to restore after sleep if suspended, otherwise -1
|}
 
With the following declarations: <code>struct KThreadLinkedList { KThread *first, *last; };</code> and <code>struct KThreadLinkedListNode { KThread *prev, *next; };</code>.
 
=Thread Scheduling Mask=
The thread scheduling mask is made of a low nibble (enum) and a high nibble (bitfield).
 
Low nibble:
 
{| class="wikitable" border="1"
|-
|-
| 0xA4
! Value
| KThread*
! Description
| Next (virtual address)
|-
|-
| 0xA8
| 0
| struct { KThread* first; KThread* last; } ptr
| The thread is not scheduled
| Pointer to linked list that has stolen it, or 0 if in normal list
|-
| 1
| The thread is scheduled
|-
| 2
| The thread is being terminated
|}
 
High nibble:
{| class="wikitable" border="1"
|-
! 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.
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