KResourceLimit

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class KResourceLimit extends KAutoObject;

Size : 0x74 bytes

Offset Type Description
0x0 u32 Pointer to vtable
0x4 u32 Reference count
0x8 s32 Max Priority
0xC s32 Max commit
0x10 s32 Max thread
0x14 s32 Max event
0x18 s32 Max mutex
0x1C s32 Max semaphore
0x20 s32 Max timer
0x24 s32 Max shared memory
0x28 s32 Max address arbiter
0x2C s32 Max CPU time
0x30 s32 Current Priority
0x34 s32 Current commit
0x38 s32 Current thread
0x3C s32 Current event
0x40 s32 Current mutex
0x44 s32 Current semaphore
0x48 s32 Current timer
0x4C s32 Current shared memory
0x50 s32 Current address arbiter
0x54 s32 Current CPU time
0x58 KObjectMutex Mutex
0x60 KPreemptionTimer Preemption timer for the current core, see below

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 ARM11 Local System Capabilities.

KPreemptionTimer:

Offset Type Description
0x0 u32 Max CPU time in ticks for preemption type 0 (default preemption type)
0x4 u32 Current timer (in watchdog timer ticks)
0x8 u32 Last remembered watchdog timer counter value
0xC u32 Max CPU time in ticks for preemption type 1

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.

Preemption type 0: this is the default, preempts threads on core1 and allow them to run only 2ms * (timeLimit / 100).

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))

"Firm" dev consoles can switch between these two types using svcKernelSetState type 6.