KThreadContext: Difference between revisions
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{| class="wikitable" border="1" | |||
|- | |||
! Offset | |||
! Type | |||
! Description | |||
|- | |||
| 0xF50 | |||
| u32[10] | |||
| SVC mode registers, r4-r11, r13, r14 | |||
|- | |||
| 0xFF8 | |||
| u32 | |||
| FPEXC, floating point exception register for thread- stored and loaded on context switches | |||
|} | |||
When switching thread contexts the kernel does, in order: | |||
* Load FPEXC | |||
* Save the LR to r1- this LR is the return back to the main scheduling and context switching function | |||
* Load r4-r11, SP, LR | |||
* Branch back to r1, preserving the LR which was just reloaded, back to the main scheduling function, but in the context of the newly switched-to thread | |||
Revision as of 21:46, 28 August 2016
Size : 0x1000 bytes (1 page)
| Offset | Type | Description |
|---|---|---|
| 0xF50 | u32[10] | SVC mode registers, r4-r11, r13, r14 |
| 0xFF8 | u32 | FPEXC, floating point exception register for thread- stored and loaded on context switches |
When switching thread contexts the kernel does, in order:
- Load FPEXC
- Save the LR to r1- this LR is the return back to the main scheduling and context switching function
- Load r4-r11, SP, LR
- Branch back to r1, preserving the LR which was just reloaded, back to the main scheduling function, but in the context of the newly switched-to thread