From 7ea1ebeea35ace2b29c8ec14b861abaad5717aab Mon Sep 17 00:00:00 2001 From: kuangyufei Date: Fri, 9 Apr 2021 14:57:47 +0800 Subject: [PATCH] =?UTF-8?q?=E6=B3=A8=E8=A7=A30=E5=8F=B7=E8=BF=9B=E7=A8=8B?= =?UTF-8?q?=E6=98=AF=E5=A6=82=E4=BD=95=E5=88=9B=E5=BB=BA=E7=9A=84=3F=20=20?= =?UTF-8?q?=20=20=20=E7=99=BE=E4=B8=87=E6=B1=89=E5=AD=97=E6=B3=A8=E8=A7=A3?= =?UTF-8?q?=20+=20=E7=99=BE=E7=AF=87=E5=8D=9A=E5=AE=A2=E5=88=86=E6=9E=90?= =?UTF-8?q?=20=3D>=20=E6=8C=96=E9=80=8F=E9=B8=BF=E8=92=99=E5=86=85?= =?UTF-8?q?=E6=A0=B8=E6=BA=90=E7=A0=81=20=20=20=20=20https://my.oschina.ne?= =?UTF-8?q?t/weharmony?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- arch/arm/arm/include/arch_config.h | 2 +- arch/arm/arm/include/los_hw_cpu.h | 13 +++--- arch/arm/arm/src/include/los_hw_pri.h | 4 +- arch/arm/arm/src/los_exc.c | 12 +++--- arch/arm/arm/src/los_hw.c | 2 +- arch/arm/arm/src/los_hw_exc.S | 6 +-- kernel/base/core/los_process.c | 40 ++++++++++--------- kernel/base/core/los_task.c | 10 ++--- kernel/base/include/los_process_pri.h | 2 +- kernel/base/include/los_task_pri.h | 14 +++---- kernel/base/sched/sched_sq/los_sched.c | 6 +-- kernel/common/los_config.c | 6 +-- .../extended/dynload/include/los_load_elf.h | 8 ++-- syscall/los_syscall.c | 10 ++--- zzz/git/push.sh | 2 +- 15 files changed, 72 insertions(+), 65 deletions(-) diff --git a/arch/arm/arm/include/arch_config.h b/arch/arm/arm/include/arch_config.h index 1a0b69ed..c78d9384 100644 --- a/arch/arm/arm/include/arch_config.h +++ b/arch/arm/arm/include/arch_config.h @@ -86,7 +86,7 @@ SPSR（saved program status register）程序状态保存寄存器. ******************************************************************************/ #define CPSR_INT_DISABLE 0xC0 /* Disable both FIQ and IRQ */ //禁止IRQ和FIQ中断,因为0xC0 = 0x80 + 0x40 #define CPSR_IRQ_DISABLE 0x80 /* IRQ disabled when =1 */ //禁止IRQ 中断 -#define CPSR_FIQ_DISABLE 0x40 /* FIQ disabled when =1 */ //禁止 FIQ中断 +#define CPSR_FIQ_DISABLE 0x40 /* FIQ disabled when =1 */ //禁止FIQ中断 #define CPSR_THUMB_ENABLE 0x20 /* Thumb mode when =1 */ //使能Thumb模式 1:CPU处于Thumb状态， 0:CPU处于ARM状态 #define CPSR_USER_MODE 0x10 //用户模式,除了用户模式，其余模式也叫特权模式,特权模式中除了系统模式以外的其余5种模式称为异常模式； #define CPSR_FIQ_MODE 0x11 //快中断模式 用于高速数据传输或通道处理 diff --git a/arch/arm/arm/include/los_hw_cpu.h b/arch/arm/arm/include/los_hw_cpu.h index 33e9d455..cd5323fd 100644 --- a/arch/arm/arm/include/los_hw_cpu.h +++ b/arch/arm/arm/include/los_hw_cpu.h @@ -131,17 +131,20 @@ STATIC INLINE VOID *ArchCurrTaskGet(VOID) { return (VOID *)(UINTPTR)ARM_SYSREG_READ(TPIDRPRW);//读c13寄存器 } - +//设置当前task ID STATIC INLINE VOID ArchCurrTaskSet(VOID *val) { ARM_SYSREG_WRITE(TPIDRPRW, (UINT32)(UINTPTR)val); } - +//向协处理器写入用户态任务ID TPIDRURO 仅用于用户态 STATIC INLINE VOID ArchCurrUserTaskSet(UINTPTR val) { ARM_SYSREG_WRITE(TPIDRURO, (UINT32)val); } -//https://www.keil.com/pack/doc/cmsis/Core_A/html/group__CMSIS__MPIDR.html +/* +* https://www.keil.com/pack/doc/cmsis/Core_A/html/group__CMSIS__MPIDR.html +* 在多处理器系统中，MPIDR为调度目的提供额外的处理器标识机制，并指示实现是否包括多处理器扩展。 +*/ STATIC INLINE UINT32 ArchCurrCpuid(VOID) { #if (LOSCFG_KERNEL_SMP == YES)//CPU多核情况 @@ -163,7 +166,7 @@ STATIC INLINE UINT32 OsMainIDGet(VOID) /* CPU interrupt mask handle implementation */ //CPU中断掩码句柄实现 #if LOSCFG_ARM_ARCH >= 6 - +//禁止中断 STATIC INLINE UINT32 ArchIntLock(VOID) { UINT32 intSave; @@ -175,7 +178,7 @@ STATIC INLINE UINT32 ArchIntLock(VOID) : "memory"); return intSave; } - +//恢复中断 STATIC INLINE UINT32 ArchIntUnlock(VOID) { UINT32 intSave; diff --git a/arch/arm/arm/src/include/los_hw_pri.h b/arch/arm/arm/src/include/los_hw_pri.h index 3c32d88d..853ffb97 100644 --- a/arch/arm/arm/src/include/los_hw_pri.h +++ b/arch/arm/arm/src/include/los_hw_pri.h @@ -59,8 +59,8 @@ typedef struct { //参考OsTaskSchedule来理解 UINT32 resved; /* It's stack 8 aligned */ UINT32 regPSR; UINT32 R[GEN_REGS_NUM]; /* R0-R12 */ - UINT32 SP; /* R13 */ - UINT32 LR; /* R14 */ + UINT32 SP; /* R13 */ //保存用户空间SP + UINT32 LR; /* R14 */ //保存用户空间LR UINT32 PC; /* R15 */ } TaskContext; diff --git a/arch/arm/arm/src/los_exc.c b/arch/arm/arm/src/los_exc.c index 1d34e21c..8c253d83 100644 --- a/arch/arm/arm/src/los_exc.c +++ b/arch/arm/arm/src/los_exc.c @@ -623,8 +623,8 @@ STATIC INLINE BOOL FindSuitableStack(UINTPTR regFP, UINTPTR *start, UINTPTR *end if (g_excFromUserMode[ArchCurrCpuid()] == TRUE) {//当前CPU在用户态执行发生异常 taskCB = OsCurrTaskGet(); - stackStart = taskCB->userMapBase; - stackEnd = taskCB->userMapBase + taskCB->userMapSize; + stackStart = taskCB->userMapBase;//用户态栈基地址,即用户态栈顶 + stackEnd = taskCB->userMapBase + taskCB->userMapSize;//用户态栈结束地址 if (IsValidFP(regFP, stackStart, stackEnd, &kvaddr) == TRUE) { found = TRUE; goto FOUND; @@ -632,22 +632,22 @@ STATIC INLINE BOOL FindSuitableStack(UINTPTR regFP, UINTPTR *start, UINTPTR *end return found; } - /* Search in the task stacks */ + /* Search in the task stacks *///找任务的内核态栈 for (index = 0; index < g_taskMaxNum; index++) { taskCB = &g_taskCBArray[index]; if (OsTaskIsUnused(taskCB)) { continue; } - stackStart = taskCB->topOfStack; - stackEnd = taskCB->topOfStack + taskCB->stackSize; + stackStart = taskCB->topOfStack;//内核态栈顶 + stackEnd = taskCB->topOfStack + taskCB->stackSize;//内核态栈底 if (IsValidFP(regFP, stackStart, stackEnd, &kvaddr) == TRUE) { found = TRUE; goto FOUND; } } - /* Search in the exc stacks */ + /* Search in the exc stacks *///从异常栈中找 for (index = 0; index < sizeof(g_excStack) / sizeof(StackInfo); index++) { stack = &g_excStack[index]; stackStart = (UINTPTR)stack->stackTop; diff --git a/arch/arm/arm/src/los_hw.c b/arch/arm/arm/src/los_hw.c index f5761f67..a3b67d5e 100644 --- a/arch/arm/arm/src/los_hw.c +++ b/arch/arm/arm/src/los_hw.c @@ -141,7 +141,7 @@ LITE_OS_SEC_TEXT_INIT VOID OsUserTaskStackInit(TaskContext *context, TSK_ENTRY_F #else context->regPSR = PSR_MODE_USR_ARM;//工作模式:用户模式 + 工作状态:arm #endif - context->R[0] = stack;//因为要回到用户态空间运行,所以要作为参数传回SP值 + context->R[0] = stack;//将用户态栈指针保存到上下文R0处 context->SP = TRUNCATE(stack, LOSCFG_STACK_POINT_ALIGN_SIZE);//改变 上下文的SP值,指向用户栈空间 context->LR = 0;//保存子程序返回地址 例如 a call b ,在b中保存 a地址 context->PC = (UINTPTR)taskEntry;//入口函数,由外部传入,由上层应用指定,固然每个都不一样. diff --git a/arch/arm/arm/src/los_hw_exc.S b/arch/arm/arm/src/los_hw_exc.S index 230e8a8d..cb4966a8 100644 --- a/arch/arm/arm/src/los_hw_exc.S +++ b/arch/arm/arm/src/los_hw_exc.S @@ -178,9 +178,9 @@ STMDA（完成操作而后地址递减）、STMED（空递减堆栈）。 */ @ Description: Software interrupt exception handler -_osExceptSwiHdl: @软中断异常处理 +_osExceptSwiHdl: @软中断异常处理,注意此时已在内核栈运行 @保存任务上下文(TaskContext) 开始... 一定要对照TaskContext来理解 - SUB SP, SP, #(4 * 16) @先申请16个栈空间用于处理本次软中断 + SUB SP, SP, #(4 * 16) @先申请16个栈空间单元用于处理本次软中断 STMIA SP, {R0-R12} @TaskContext.R[GEN_REGS_NUM] STMIA从左到右执行,先放R0 .. R12 MRS R3, SPSR @读取本模式下的SPSR值 MOV R4, LR @保存回跳寄存器LR @@ -201,7 +201,7 @@ _osExceptSwiHdl: @软中断异常处理 @保存任务上下文(TaskContext) 结束 MOV FP, #0 @ Init frame pointer CPSIE I @开中断,表明在系统调用期间可响应中断 - BLX OsArmA32SyscallHandle /*交给C语言处理系统调用*/ + BLX OsArmA32SyscallHandle /*交给C语言处理系统调用,参数为R0,指向TaskContext的开始位置*/ CPSID I @执行后续指令前必须先关中断 @恢复任务上下文(TaskContext) 开始 POP_FPU_REGS R1 @弹出FP值给R1 diff --git a/kernel/base/core/los_process.c b/kernel/base/core/los_process.c index a387468a..bb7af595 100644 --- a/kernel/base/core/los_process.c +++ b/kernel/base/core/los_process.c @@ -525,16 +525,19 @@ LITE_OS_SEC_TEXT_INIT UINT32 OsProcessInit(VOID) LOS_ListInit(&g_processRecyleList);//进程回收链表初始化,回收完成后进入g_freeProcess等待再次被申请使用 for (index = 0; index < g_processMaxNum; index++) {//进程池循环创建 - g_processCBArray[index].processID = index;//进程ID[0-g_processMaxNum]赋值 + g_processCBArray[index].processID = index;//进程ID[0-g_processMaxNum-1]赋值 g_processCBArray[index].processStatus = OS_PROCESS_FLAG_UNUSED;// 默认都是白纸一张,贴上未使用标签 LOS_ListTailInsert(&g_freeProcess, &g_processCBArray[index].pendList);//注意g_freeProcess挂的是pendList节点,所以使用要通过OS_PCB_FROM_PENDLIST找到进程实体. } g_userInitProcess = 1; /* 1: The root process ID of the user-mode process is fixed at 1 *///用户态的根进程 - LOS_ListDelete(&g_processCBArray[g_userInitProcess].pendList);// 清空g_userInitProcess pend链表 + LOS_ListDelete(&g_processCBArray[g_userInitProcess].pendList);// 将1号进程从空闲链表上摘出去 g_kernelInitProcess = 2; /* 2: The root process ID of the kernel-mode process is fixed at 2 *///内核态的根进程 - LOS_ListDelete(&g_processCBArray[g_kernelInitProcess].pendList);// 清空g_kernelInitProcess pend链表 + LOS_ListDelete(&g_processCBArray[g_kernelInitProcess].pendList);// 将2号进程从空闲链表上摘出去 + + //注意:这波骚操作之后,g_freeProcess链表上还有,0,3,4,...g_processMaxNum-1号进程.创建进程是从g_freeProcess上申请 + //即下次申请到的将是0号进程,而 OsCreateIdleProcess 将占有0号进程. return LOS_OK; } @@ -553,10 +556,10 @@ STATIC UINT32 OsCreateIdleProcess(VOID) } //创建一个名叫"KIdle"的进程,并创建一个idle task,CPU空闲的时候就待在 idle task中等待被唤醒 ret = LOS_Fork(CLONE_FILES, "KIdle", (TSK_ENTRY_FUNC)OsIdleTask, LOSCFG_BASE_CORE_TSK_IDLE_STACK_SIZE); - if (ret < 0) { + if (ret < 0) {//内核进程的fork并不会一次调用,返回两次,此子进程执行的开始位置是参数OsIdleTask return LOS_NOK; } - g_kernelIdleProcess = (UINT32)ret;//返回进程ID + g_kernelIdleProcess = (UINT32)ret;//返回 0号进程 idleProcess = OS_PCB_FROM_PID(g_kernelIdleProcess);//通过ID拿到进程实体 *idleTaskID = idleProcess->threadGroupID;//绑定CPU的IdleTask,或者说改变CPU现有的idle任务 @@ -619,14 +622,14 @@ STATIC LosProcessCB *OsGetFreePCB(VOID) UINT32 intSave; SCHEDULER_LOCK(intSave); - if (LOS_ListEmpty(&g_freeProcess)) {//空闲池里还有未分配的task? + if (LOS_ListEmpty(&g_freeProcess)) {//空闲池里还有未分配的进程? SCHEDULER_UNLOCK(intSave); PRINT_ERR("No idle PCB in the system!\n"); return NULL; } processCB = OS_PCB_FROM_PENDLIST(LOS_DL_LIST_FIRST(&g_freeProcess));//拿到PCB,通过OS_PCB_FROM_PENDLIST是因为通过pendlist 节点挂在 freelist链表上. - LOS_ListDelete(&processCB->pendList);//分配出来了就要在freelist将自己摘除 + LOS_ListDelete(&processCB->pendList);//将自己从g_freeProcess链表摘除 SCHEDULER_UNLOCK(intSave); return processCB; @@ -907,7 +910,7 @@ LITE_OS_SEC_TEXT_INIT UINT32 OsKernelInitProcess(VOID) processCB->processStatus &= ~OS_PROCESS_STATUS_INIT;// 进程初始化位 置1 g_processGroup = processCB->group;//全局进程组指向了KProcess所在的进程组 LOS_ListInit(&g_processGroup->groupList);// 进程组链表初始化 - OsCurrProcessSet(processCB);// 设置为当前进程 + OsCurrProcessSet(processCB);// 将KProcess设置为当前进程 return OsCreateIdleProcess();// 创建一个空闲状态的进程 } @@ -1547,7 +1550,7 @@ LITE_OS_SEC_TEXT UINT32 OsExecRecycleAndInit(LosProcessCB *processCB, const CHAR LOS_VmSpaceFree(oldSpace);//ELF已经接管了进程,进程的原有虚拟空间要被释放掉 return LOS_OK; } -//进程层面的开始执行, entry为入口函数 ,其中 创建好task,task上下文 等待调度真正执行, sp:栈指针 mapBase:栈底 mapSize:栈大小 +//执行用户态任务, entry为入口函数 ,其中 创建好task,task上下文 等待调度真正执行, sp:栈指针 mapBase:栈底 mapSize:栈大小 LITE_OS_SEC_TEXT UINT32 OsExecStart(const TSK_ENTRY_FUNC entry, UINTPTR sp, UINTPTR mapBase, UINT32 mapSize) { LosProcessCB *processCB = NULL; @@ -1572,12 +1575,13 @@ LITE_OS_SEC_TEXT UINT32 OsExecStart(const TSK_ENTRY_FUNC entry, UINTPTR sp, UINT taskCB = OsCurrTaskGet();//获取当前任务 processCB->threadGroupID = taskCB->taskID;//threadGroupID是进程的主线程ID,也就是应用程序 main函数线程 - taskCB->userMapBase = mapBase;//任务用户态栈底地址 - taskCB->userMapSize = mapSize;//任务用户态栈大小 + taskCB->userMapBase = mapBase;//用户态栈顶 + taskCB->userMapSize = mapSize;//用户态栈大小 taskCB->taskEntry = (TSK_ENTRY_FUNC)entry;//任务的入口函数 - taskContext = (TaskContext *)OsTaskStackInit(taskCB->taskID, taskCB->stackSize, (VOID *)taskCB->topOfStack, FALSE);//创建任务上下文 - OsUserTaskStackInit(taskContext, taskCB->taskEntry, sp);//用户进程任务栈初始化 + taskContext = (TaskContext *)OsTaskStackInit(taskCB->taskID, taskCB->stackSize, (VOID *)taskCB->topOfStack, FALSE);//在内核栈中创建任务上下文 + OsUserTaskStackInit(taskContext, taskCB->taskEntry, sp);//初始化用户栈,将内核栈中上下文的 context->R[0] = sp ,context->sp = sp + //这样做的目的是将用户栈SP保存到内核栈中, SCHEDULER_UNLOCK(intSave);//解锁 return LOS_OK; } @@ -1641,7 +1645,7 @@ LITE_OS_SEC_TEXT_INIT UINT32 OsUserInitProcess(VOID) (VOID)memset_s((VOID *)((UINTPTR)userText + userInitBssStart - userInitTextStart), initBssSize, 0, initBssSize);// 除了代码段，其余都清0 - stack = OsUserInitStackAlloc(g_userInitProcess, &size);//分配任务在用户态下的运行栈,大小为1M,注意此内存来自进程空间,而非内核空间. + stack = OsUserInitStackAlloc(g_userInitProcess, &size);//分配任务在用户态下的运行栈,大小为1M,注意此内存来自用户空间. if (stack == NULL) { PRINTK("user init process malloc user stack failed!\n"); ret = LOS_NOK; @@ -1696,7 +1700,7 @@ STATIC VOID OsInitCopyTaskParam(LosProcessCB *childProcessCB, const CHAR *name, childPara->userParam.userArea = mainThread->userArea; //用户态栈区栈顶位置 childPara->userParam.userMapBase = mainThread->userMapBase; //用户态栈底 childPara->userParam.userMapSize = mainThread->userMapSize; //用户态栈大小 - } else { + } else {//注意内核态进程创建任务的入口由外界指定,例如 OsCreateIdleProcess 指定了OsIdleTask childPara->pfnTaskEntry = (TSK_ENTRY_FUNC)entry;//参数(sp)为内核态入口地址 childPara->uwStackSize = size;//参数(size)为内核态栈大小 } @@ -1987,17 +1991,17 @@ LITE_OS_SEC_TEXT VOID LOS_Exit(INT32 status) OsTaskExitGroup((UINT32)status); OsProcessExit(OsCurrTaskGet(), (UINT32)status); } -//获取用户进程的根进程,所有用户进程都是g_processCBArray[g_userInitProcess] fork来的 +//获取用户态进程的根进程,所有用户进程都是g_processCBArray[g_userInitProcess] fork来的 LITE_OS_SEC_TEXT UINT32 OsGetUserInitProcessID(VOID) { return g_userInitProcess; } -//获取Idel进程,CPU不公正时待的地方,等待被事件唤醒 +//获取Idel进程,CPU休息时待的地方,等待被事件唤醒 LITE_OS_SEC_TEXT UINT32 OsGetIdleProcessID(VOID) { return g_kernelIdleProcess; } -//获取内核进程的根进程,所有内核进程都是g_processCBArray[g_kernelInitProcess] fork来的,包括g_processCBArray[g_kernelIdleProcess]进程 +//获取内核态进程的根进程,所有内核进程都是g_processCBArray[g_kernelInitProcess] fork来的,包括g_processCBArray[g_kernelIdleProcess]进程 LITE_OS_SEC_TEXT UINT32 OsGetKernelInitProcessID(VOID) { return g_kernelInitProcess; diff --git a/kernel/base/core/los_task.c b/kernel/base/core/los_task.c index 1af18f63..9aa7868f 100644 --- a/kernel/base/core/los_task.c +++ b/kernel/base/core/los_task.c @@ -767,7 +767,7 @@ LITE_OS_SEC_TEXT_INIT STATIC VOID OsTaskCBInitBase(LosTaskCB *taskCB, taskCB->args[1] = initParam->auwArgs[1]; taskCB->args[2] = initParam->auwArgs[2]; taskCB->args[3] = initParam->auwArgs[3]; - taskCB->topOfStack = (UINTPTR)topStack; //内核态栈起始位置 + taskCB->topOfStack = (UINTPTR)topStack; //内核态栈顶 taskCB->stackSize = initParam->uwStackSize;// taskCB->priority = initParam->usTaskPrio; taskCB->taskEntry = initParam->pfnTaskEntry; @@ -805,7 +805,7 @@ LITE_OS_SEC_TEXT_INIT STATIC UINT32 OsTaskCBInit(LosTaskCB *taskCB, const TSK_IN LosProcessCB *processCB = NULL; OsTaskCBInitBase(taskCB, stackPtr, topStack, initParam);//初始化任务的基本信息, - //taskCB->stackPointer = stackPtr ,用户态时将改写taskCB->stackPointer指向 + //taskCB->stackPointer指向内核态栈 sp位置,该位置存着 任务初始上下文 SCHEDULER_LOCK(intSave); processCB = OS_PCB_FROM_PID(initParam->processID);//通过ID获取PCB ,单核进程数最多64个 @@ -817,7 +817,7 @@ LITE_OS_SEC_TEXT_INIT STATIC UINT32 OsTaskCBInit(LosTaskCB *taskCB, const TSK_IN taskCB->userMapBase = initParam->userParam.userMapBase; taskCB->userMapSize = initParam->userParam.userMapSize; OsUserTaskStackInit(taskCB->stackPointer, taskCB->taskEntry, initParam->userParam.userSP);//初始化用户态任务栈 - //这里要注意,任务的上下文是始终保存在内核栈空间,但用户态时运行是在用户态的栈空间.(因为SP指向了用户态空间) + //这里要注意,任务的上下文是始终保存在内核栈空间,而用户态时运行在用户态栈空间.(context->SP = userSP 指向了用户态栈空间) } if (!processCB->threadNumber) {//进程线程数量为0时， @@ -1584,8 +1584,8 @@ LITE_OS_SEC_TEXT_MINOR UINT32 LOS_TaskInfoGet(UINT32 taskID, TSK_INFO_S *taskInf taskInfo->usTaskStatus = taskCB->taskStatus; taskInfo->usTaskPrio = taskCB->priority; - taskInfo->uwStackSize = taskCB->stackSize; - taskInfo->uwTopOfStack = taskCB->topOfStack; + taskInfo->uwStackSize = taskCB->stackSize;//内核态栈大小 + taskInfo->uwTopOfStack = taskCB->topOfStack;//内核态栈顶位置 taskInfo->uwEventMask = taskCB->eventMask; taskInfo->taskEvent = taskCB->taskEvent; taskInfo->pTaskSem = taskCB->taskSem; diff --git a/kernel/base/include/los_process_pri.h b/kernel/base/include/los_process_pri.h index 77443252..bcf03366 100644 --- a/kernel/base/include/los_process_pri.h +++ b/kernel/base/include/los_process_pri.h @@ -386,7 +386,7 @@ STATIC INLINE LosProcessCB *OsCurrProcessGet(VOID) LOS_IntRestore(intSave);//恢复硬件中断 return runProcess; } -//设置当前进程,加入g_runProcess中 +//设置使用CPU的当前进程,加入g_runProcess中 STATIC INLINE VOID OsCurrProcessSet(const LosProcessCB *process) { g_runProcess[ArchCurrCpuid()] = (LosProcessCB *)process; diff --git a/kernel/base/include/los_task_pri.h b/kernel/base/include/los_task_pri.h index 575a432e..4dd83535 100644 --- a/kernel/base/include/los_task_pri.h +++ b/kernel/base/include/los_task_pri.h @@ -294,13 +294,13 @@ extern SPIN_LOCK_S g_taskSpin;//任务自旋锁 #define OS_TCB_NAME_LEN 32 typedef struct { - VOID *stackPointer; /**< Task stack pointer */ //栈指针,SP位置,切换任务时先保存上下文并指向TaskContext位置. + VOID *stackPointer; /**< Task stack pointer */ //内核栈指针位置,内核栈默认保存了初始的上下文信息. UINT16 taskStatus; /**< Task status */ //各种状态标签，可以拥有多种标签，按位标识 UINT16 priority; /**< Task priority */ //任务优先级[0:31],默认是31级 UINT16 policy; //任务的调度方式(三种 .. LOS_SCHED_RR ) UINT16 timeSlice; /**< Remaining time slice *///剩余时间片 - UINT32 stackSize; /**< Task stack size */ //栈大小,内存来自内核空间 - UINTPTR topOfStack; /**< Task stack top */ //栈顶 bottom = top + size,内存来自内核空间 + UINT32 stackSize; /**< Task stack size */ //内核态栈大小,内存来自内核空间 + UINTPTR topOfStack; /**< Task stack top */ //内核态栈顶 bottom = top + size UINT32 taskID; /**< Task ID */ //任务ID，任务池本质是一个大数组，ID就是数组的索引，默认 < 128 TSK_ENTRY_FUNC taskEntry; /**< Task entrance function */ //任务执行入口函数 VOID *joinRetval; /**< pthread adaption */ //用来存储join线程的返回值 @@ -334,8 +334,8 @@ typedef struct { SchedStat schedStat; /**< Schedule statistics */ //调度统计 #endif #endif - UINTPTR userArea; //用户区域,由运行时划定,根据运行态不同而不同 - UINTPTR userMapBase; //内存来自进程空间,用户态下的栈底位置,和topOfStack有本质的区别. + UINTPTR userArea; //用户空间,由运行时划定,根据运行态不同而不同 + UINTPTR userMapBase; //用户态栈基地址,内存来自用户空间,和topOfStack有本质的区别. UINT32 userMapSize; /**< user thread stack size ,real size : userMapSize + USER_STACK_MIN_SIZE */ UINT32 processID; /**< Which belong process *///所属进程ID FutexNode futex; //实现快锁功能 @@ -395,12 +395,12 @@ STATIC INLINE LosTaskCB *OsCurrTaskGet(VOID) { return (LosTaskCB *)ArchCurrTaskGet(); } -//设置当前CPUcore运行任务 +//告诉协处理器当前任务使用范围为内核空间 STATIC INLINE VOID OsCurrTaskSet(LosTaskCB *task) { ArchCurrTaskSet(task); } -//用户模式下设置当前Cpucore运行任务，参数为线程 +//告诉协处理器当前任务使用范围为 用户空间 STATIC INLINE VOID OsCurrUserTaskSet(UINTPTR thread) { ArchCurrUserTaskSet(thread); diff --git a/kernel/base/sched/sched_sq/los_sched.c b/kernel/base/sched/sched_sq/los_sched.c index 458f0e33..b3d0fdeb 100644 --- a/kernel/base/sched/sched_sq/los_sched.c +++ b/kernel/base/sched/sched_sq/los_sched.c @@ -130,10 +130,10 @@ VOID OsSchedResched(VOID) newTask->timeSlice = LOSCFG_BASE_CORE_TIMESLICE_TIMEOUT;//给新任务时间片 默认 20ms } - OsCurrTaskSet((VOID*)newTask);//设置新的task为CPU核的当前任务 + OsCurrTaskSet((VOID*)newTask);//设置新的task为当前任务 - if (OsProcessIsUserMode(newProcess)) {//用户模式需自带栈空间 - OsCurrUserTaskSet(newTask->userArea);//设置task栈空间 + if (OsProcessIsUserMode(newProcess)) {//用户态进程 + OsCurrUserTaskSet(newTask->userArea);//向CP15 (c13, 0, c0, 3) 设置当前线程ID } PRINT_TRACE("cpu%d run process name: (%s) pid: %d status: %x threadMap: %x task name: (%s) tid: %d status: %x ->\n" diff --git a/kernel/common/los_config.c b/kernel/common/los_config.c index fbd75e34..49573829 100644 --- a/kernel/common/los_config.c +++ b/kernel/common/los_config.c @@ -296,7 +296,7 @@ LITE_OS_SEC_TEXT_INIT INT32 OsMain(VOID) } #endif - ret = OsKernelInitProcess();// 完成内核进程的初始化 + ret = OsKernelInitProcess();// 初始化内核态根进程 if (ret != LOS_OK) { return ret; } @@ -387,7 +387,7 @@ STATIC UINT32 OsSystemInitTaskCreate(VOID) TSK_INIT_PARAM_S sysTask; (VOID)memset_s(&sysTask, sizeof(TSK_INIT_PARAM_S), 0, sizeof(TSK_INIT_PARAM_S)); - sysTask.pfnTaskEntry = (TSK_ENTRY_FUNC)SystemInit;//任务的入口函数，这个任务由外部提供 比如..\vendor\hi3516dv300\module_init\src\system_init.c + sysTask.pfnTaskEntry = (TSK_ENTRY_FUNC)SystemInit;//任务的入口函数，这个任务由外部提供比如..\vendor\hi3516dv300\module_init\src\system_init.c sysTask.uwStackSize = LOSCFG_BASE_CORE_TSK_DEFAULT_STACK_SIZE;//16K sysTask.pcName = "SystemInit";//任务的名称 sysTask.usTaskPrio = LOSCFG_BASE_CORE_TSK_DEFAULT_PRIO;// 内核默认优先级为10 @@ -423,7 +423,7 @@ UINT32 OsSystemInit(VOID) #ifdef LOSCFG_COMPAT_LINUXKPI g_pstSystemWq = create_workqueue("system_wq"); #endif - ret = OsSystemInitTaskCreate();//创建 "SystemInit" 任务 + ret = OsSystemInitTaskCreate();//创建 "SystemInit" 任务,用户创建用户态根进程 if (ret != LOS_OK) { return ret; } diff --git a/kernel/extended/dynload/include/los_load_elf.h b/kernel/extended/dynload/include/los_load_elf.h index e1c70a85..4dd57f28 100644 --- a/kernel/extended/dynload/include/los_load_elf.h +++ b/kernel/extended/dynload/include/los_load_elf.h @@ -92,11 +92,11 @@ typedef struct { INT32 envc; CHAR *const *argv; CHAR *const *envp; - UINTPTR stackTop; - UINTPTR stackTopMax; - UINTPTR stackBase; + UINTPTR stackTop; //当前栈顶 + UINTPTR stackTopMax; //栈顶最大值,其实必 stackTopMax < stackTop + UINTPTR stackBase; //栈底 UINTPTR stackParamBase; - UINT32 stackSize; + UINT32 stackSize;//栈大小 INT32 stackProt; UINTPTR loadAddr; UINTPTR elfEntry; //入口函数位置 diff --git a/syscall/los_syscall.c b/syscall/los_syscall.c index 45bc660a..ae977356 100644 --- a/syscall/los_syscall.c +++ b/syscall/los_syscall.c @@ -94,7 +94,7 @@ void SyscallHandleInit(void) /* The SYSCALL ID is in R7 on entry. Parameters follow in R0..R6 */ /****************************************************************** -由汇编调用,见于 los_hw_exc.s 第197行 BLX OsArmA32SyscallHandle +由汇编调用,见于 los_hw_exc.s / BLX OsArmA32SyscallHandle SYSCALL是产生系统调用时触发的信号,R7寄存器存放具体的系统调用ID,也叫系统调用号 regs:参数就是所有寄存器 注意:本函数在用户态和内核态下都可能被调用到 @@ -112,8 +112,8 @@ LITE_OS_SEC_TEXT UINT32 *OsArmA32SyscallHandle(UINT32 *regs) return regs; } - if (cmd == __NR_sigreturn) {//此时运行在内核栈,程序返回的调用,从内核态返回用户态时触发 - OsRestorSignalContext(regs);//恢复信号上下文,执行完函数后,切到了用户栈 + if (cmd == __NR_sigreturn) {//收到 __NR_sigreturn 信号 + OsRestorSignalContext(regs);//恢复信号上下文 return regs; } @@ -131,7 +131,7 @@ LITE_OS_SEC_TEXT UINT32 *OsArmA32SyscallHandle(UINT32 *regs) case ARG_NUM_1: ret = (*(SyscallFun1)handle)(regs[REG_R0]);//执行系统调用,类似 SysUnlink(pathname); break; - case ARG_NUM_2://@note_thinking 如何是两个参数的系统调用,这里传的确是三个参数,任务栈中会出现怎样的情况呢? + case ARG_NUM_2://如何是两个参数的系统调用,这里传三个参数也没有问题,因被调用函数不会去取用R2值 case ARG_NUM_3: ret = (*(SyscallFun3)handle)(regs[REG_R0], regs[REG_R1], regs[REG_R2]);//类似 SysExecve(fileName, argv, envp); break; @@ -146,7 +146,7 @@ LITE_OS_SEC_TEXT UINT32 *OsArmA32SyscallHandle(UINT32 *regs) } regs[REG_R0] = ret;//R0保存系统调用返回值 - OsSaveSignalContext(regs);//保存用户栈现场 + OsSaveSignalContext(regs);//保存信号上下文现场 /* Return the last value of curent_regs. This supports context switches on return from the exception. * That capability is only used with theSYS_context_switch system call. diff --git a/zzz/git/push.sh b/zzz/git/push.sh index e988a2a5..8bd80b0b 100644 --- a/zzz/git/push.sh +++ b/zzz/git/push.sh @@ -1,5 +1,5 @@ git add -A -git commit -m '用户态,内核态代码注解 +git commit -m '注解0号进程是如何创建的? 百万汉字注解 + 百篇博客分析 => 挖透鸿蒙内核源码 https://my.oschina.net/weharmony ' -- GitLab