Magenta Job/Process/Thread Study

Thread

syscall: kernel/lib/syscalls/syscalls_task.cpp sys_thread_create --> process->CreateUserThread ----> ut->Initialize(name.data(), name.length());

source: kernel/lib/magenta/user_thread.cpp

Init. flow

1. allocate_stack
2. new a LK thread assign user_thread to itself register thread state change callback
3. attach process address space vmm_aspace

Thread Stucture

header: include/kernel/thread.h 最新LK的thread: https://github.com/littlekernel/lk/blob/master/include/kernel/thread.h ^ 已經有VMM, SMP相關的欄位

AOSP Trusty裡面LK的thread: https://android.googlesource.com/trusty/lk/common/+/master/include/kernel/thread.h ^ 比較舊

New attributes in Magenta

1. user thread related
2. signal
3. priority boost
4. interruptable
5. profiling & debug related
6. default一定有vmm_aspace
7. default一定有SMP

Thread context switch

source: kernel/kernel/thread.c

void thread_resched(void)

---> void vmm_context_switch(vmm_aspace_t oldspace, vmm_aspace_t newaspace) kernel/kernel/vm/vmm.c

-----> arch_mmu_context_switch (Platform dependent here) // change VM space

Process

source: kernel/lib/magenta/process_dispatcher.cpp

System Call kernel entries

source location: kernel/lib/syscalls/

接到各個kernel space object dispatcher