### liteos_a多核启动大体过程-20211024

**core0**

kernel/liteos_a/arch/arm/arm/src/startup/reset_vector_mp.S
    将内核映像由ROM的物理地址0搬移至RAM的物理地址0x40000000
    用device/qemu/arm_virt/liteos_a/board/platform.c中的g_archMmuInitMapping建立页表g_firstPageTable
    启用MMU
    初始化栈
    清零BSS段

kernel/liteos_a/kernel/common/main.c::main
    kernel/liteos_a/kernel/common/los_config.c::OsMain
        kernel/liteos_a/kernel/base/core/los_task.c::OsSetMainTask
            将当前线程设置主线程"osMain"，置为当前线程
        **kernel/liteos_a/kernel/common/los_init.c::OsInitCall**LOS_INIT_LEVEL_EARLIEST
        (LOS_INIT_LEVEL的原理是链接时设置有序的不同的只读数据段，每段存放若干函数地址钩子；core0控制level的递进)
            初始化shell的logger、dmesg
        设置时钟、中断
        **kernel/liteos_a/kernel/common/los_init.c::OsInitCall**LOS_INIT_LEVEL_ARCH_EARLY（空）
        初始化uart
        **kernel/liteos_a/kernel/common/los_init.c::OsInitCall**LOS_INIT_LEVEL_PLATFORM_EARLY（空）
        打印"main core booting up..."
        kernel/liteos_a/kernel/base/core/los_task.c::OsTaskInit
            （静态）分配并初始化TCB数组
            kernel/liteos_a/kernel/base/sched/sched_sq/los_sched.c::OsSchedInit
                分配并初始化调度数据结构
        **kernel/liteos_a/kernel/common/los_init.c::OsInitCall**LOS_INIT_LEVEL_KMOD_PREVM（空）
        kernel/liteos_a/kernel/base/vm/los_vm_boot.c::OsSysMemInit
            kernel/liteos_a/kernel/base/vm/los_vm_map.c::OsKSpaceInit
                kernel/liteos_a/arch/arm/arm/src/los_arch_mmu.c::OsArchMmuInit
                    初始化内核VSpace和malloc VSpace，将g_firstPageTable设为内核页表
            kernel/liteos_a/kernel/base/mem/tlsf/los_memory.c::OsKHeapInit
                kernel/liteos_a/kernel/base/vm/los_vm_boot.c::OsVmBootMemAlloc
                    设置内核堆
            kernel/liteos_a/kernel/base/vm/los_vm_page.c::OsVmPageStartup
                设置可用物理内存页、段数据结构
            kernel/liteos_a/arch/arm/arm/src/los_arch_mmu.c::OsInitMappingStartUp
                重设内核页表属性
        **kernel/liteos_a/kernel/common/los_init.c::OsInitCall**LOS_INIT_LEVEL_VM_COMPLETE
            初始化共享内存数据结构
        初始化sem、queue
        kernel/liteos_a/kernel/base/core/los_process.c::OsSystemProcessCreate
            （静态）分配并初始化PCB数组，创建内核进程、idle进程线程
        kernel/liteos_a/arch/arm/arm/src/los_arch_mmu.c::OsArchMmuInitPerCPU
            内核、用户页表访问分离
        **kernel/liteos_a/kernel/common/los_init.c::OsInitCall**LOS_INIT_LEVEL_ARCH
            blackbox
        **kernel/liteos_a/kernel/common/los_init.c::OsInitCall**LOS_INIT_LEVEL_PLATFORM
            bsd
            blackbox system adapter
        kernel/liteos_a/kernel/base/core/los_swtmr.c::OsSwtmrInit
            初始化定时器、创建定时器线程
        **kernel/liteos_a/kernel/common/los_init.c::OsInitCall**LOS_INIT_LEVEL_KMOD_BASIC
            VFS
        **kernel/liteos_a/kernel/common/los_init.c::OsInitCall**LOS_INIT_LEVEL_KMOD_EXTENDED
            linux work queue
            device perf
            device trace
            procFS
            futex
            cpup
            hidumper
            hilog
            liteIPC
            perf
            power manager
            trace
            VDSO
            syscall
        kernel/liteos_a/kernel/base/core/los_smp.c::OsSmpInit
            kernel/liteos_a/arch/arm/arm/src/smp.c::HalArchCpuOn
                device/qemu/arm_virt/liteos_a/board/platform.c::
                    释放其它core
                    打印"releasing secondary cores"
                逐个释放并等待所有core完成启动
        **所有core已完成启动，开始并行执行**
        **LOS_INIT_LEVEL_KMOD_TASK由自旋锁保护，粒度为单个钩子函数，可能由不同的核执行**
        **kernel/liteos_a/kernel/common/los_init.c::OsInitCall**LOS_INIT_LEVEL_KMOD_TASK
            创建资源管理线程
            MP多核管理
            创建OOM线程
            创建SystemInit线程--device/qemu/arm_virt/liteos_a/board/os_adapt/os_adapt.c::SystemInit
            创建CPUP防守定时任务
            **同步等待所有core都完成本阶段**
    kernel/liteos_a/kernel/base/sched/sched_sq/los_sched.c::OsSchedStart
        **开始调度**
        打印“cpu 0 entering scheduler”

**core1**
kernel/liteos_a/arch/arm/arm/src/startup/reset_vector_mp.S
    设置svc栈
    用core0建立的页表启用MMU
kernel/liteos_a/arch/arm/arm/src/smp.c::HalSecondaryCpuStart
    用core0的主线程作为当前线程
    **置启动完毕标志，core0开始释放并等待下一core；本core继续执行**
    kernel/liteos_a/arch/arm/arm/src/los_arch_mmu.c::OsArchMmuInitPerCPU
        内核、用户页表访问分离
    kernel/liteos_a/arch/arm/gic/gic_v2.c::HalIrqInitPercpu
        使能硬件中断
    kernel/liteos_a/kernel/base/core/los_smp.c::OsSmpSecondaryInit
        用core0建立的内核init进程
        初始化定时器、创建定时器线程
        创建idle线程
        **kernel/liteos_a/kernel/common/los_init.c::OsInitCall**LOS_INIT_LEVEL_KMOD_TASK
            **同步等待所有core都完成本阶段**
    kernel/liteos_a/kernel/base/sched/sched_sq/los_sched.c::OsSchedStart
        **开始调度**
        打印“cpu 1 entering scheduler”

#### SystemInit线程的执行内容-20211024
    net_init
    DeviceManagerStart逐一加载在HDF注册的驱动
    获取启动参数（通过读取存储设备）
    OsMountRootfs
    终端控制台
    kernel/liteos_a/kernel/base/core/los_process.c::OsUserInitProcess
        创建用户进程

#### 用户init进程线程

kernel/liteos_a/kernel/base/core/los_process.c::OsUserInitProcess
    初始化进程的IPC池