Changes

1,018 bytes added ,  00:29, 12 December 2016
no edit summary
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| 0x60
 
| 0x60
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| KPreemptionTimer
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| Preemption timer for the current core, see below
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|}
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There are 4 KResourceLimit objects created on the kernel heap.  Each is used for a different category specified by the exheader's resource limit category specifier in the exheader [[NCCH/Extended_Header#ARM11_Local_System_Capabilities|ARM11 Local System Capabilities]].
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'''KPreemptionTimer''':
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{| class="wikitable" border="1"
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|-
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!  Offset
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! Type
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!  Description
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|-
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| 0x0
 
| u32
 
| u32
| CPU time available in ticks
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| Max CPU time in ticks for preemption type 0 (default preemption type)
 
|-
 
|-
| 0x64
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| 0x4
 
| u32
 
| u32
| Unknown
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| Current timer (in watchdog timer ticks)
 
|-
 
|-
| 0x68
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| 0x8
 
| u32
 
| u32
| Unknown
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| Last remembered watchdog timer counter value
 
|-
 
|-
| 0x6C
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| 0xC
| u32
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| u32  
| Unknown
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| Max CPU time in ticks for preemption type 1
 
|}
 
|}
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A call to svcSetResourceLimitValues with a limit value of 1000 for CPU time must be done first to set up some global variables and the associated [[KTimeableInterruptEvent]] instances, and another call needs to be made to actually enable preemption.
   −
There are 4 KResourceLimit objects created on the kernel heap. Each is used for a different category specified by the exheader's resource limit category specifier in the exheader [[NCCH/Extended_Header#ARM11_Local_System_Capabilities|ARM11 Local System Capabilities]].
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Preemption type 0: this is the default, preempts threads on core1 and allow them to run only 2ms * (timeLimit / 100).
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Preemption type 1: ''seems'' to be borked, it was apparently intended to preempt threads on all cores but seems to only preempt the kernel thread running the preemptor itself and threads on core1... (time slice: 12.5ms * (timeLimit / 100))
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"Firm" dev consoles can switch between these two types using svcKernelSetState type 6.