/* ************************************************************************************************************************ * uC/OS-III * The Real-Time Kernel * * (c) Copyright 2009-2011; Micrium, Inc.; Weston, FL * All rights reserved. Protected by international copyright laws. * * MUTEX MANAGEMENT * * File : OS_MUTEX.C * By : JJL * Version : V3.02.00 * * LICENSING TERMS: * --------------- * uC/OS-III is provided in source form for FREE short-term evaluation, for educational use or * for peaceful research. If you plan or intend to use uC/OS-III in a commercial application/ * product then, you need to contact Micrium to properly license uC/OS-III for its use in your * application/product. We provide ALL the source code for your convenience and to help you * experience uC/OS-III. The fact that the source is provided does NOT mean that you can use * it commercially without paying a licensing fee. * * Knowledge of the source code may NOT be used to develop a similar product. * * Please help us continue to provide the embedded community with the finest software available. * Your honesty is greatly appreciated. * * You can contact us at www.micrium.com, or by phone at +1 (954) 217-2036. ************************************************************************************************************************ */ #include #ifdef VSC_INCLUDE_SOURCE_FILE_NAMES const CPU_CHAR *os_mutex__c = "$Id: $"; #endif #if OS_CFG_MUTEX_EN > 0u /* ************************************************************************************************************************ * CREATE A MUTEX * * Description: This function creates a mutex. * * Arguments : p_mutex is a pointer to the mutex to initialize. Your application is responsible for allocating * storage for the mutex. * * p_name is a pointer to the name you would like to give the mutex. * * p_err is a pointer to a variable that will contain an error code returned by this function. * * OS_ERR_NONE if the call was successful * OS_ERR_CREATE_ISR if you called this function from an ISR * OS_ERR_ILLEGAL_CREATE_RUN_TIME if you are trying to create the Mutex after you called * OSSafetyCriticalStart(). * OS_ERR_NAME if 'p_name' is a NULL pointer * OS_ERR_OBJ_CREATED if the mutex has already been created * OS_ERR_OBJ_PTR_NULL if 'p_mutex' is a NULL pointer * * Returns : none ************************************************************************************************************************ */ void OSMutexCreate (OS_MUTEX *p_mutex, CPU_CHAR *p_name, OS_ERR *p_err) { CPU_SR_ALLOC(); #ifdef OS_SAFETY_CRITICAL if (p_err == (OS_ERR *)0) { OS_SAFETY_CRITICAL_EXCEPTION(); return; } #endif #ifdef OS_SAFETY_CRITICAL_IEC61508 if (OSSafetyCriticalStartFlag == DEF_TRUE) { *p_err = OS_ERR_ILLEGAL_CREATE_RUN_TIME; return; } #endif #if OS_CFG_CALLED_FROM_ISR_CHK_EN > 0u if (OSIntNestingCtr > (OS_NESTING_CTR)0) { /* Not allowed to be called from an ISR */ *p_err = OS_ERR_CREATE_ISR; return; } #endif #if OS_CFG_ARG_CHK_EN > 0u if (p_mutex == (OS_MUTEX *)0) { /* Validate 'p_mutex' */ *p_err = OS_ERR_OBJ_PTR_NULL; return; } #endif CPU_CRITICAL_ENTER(); p_mutex->Type = OS_OBJ_TYPE_MUTEX; /* Mark the data structure as a mutex */ p_mutex->NamePtr = p_name; p_mutex->OwnerTCBPtr = (OS_TCB *)0; p_mutex->OwnerNestingCtr = (OS_NESTING_CTR)0; /* Mutex is available */ p_mutex->TS = (CPU_TS )0; p_mutex->OwnerOriginalPrio = OS_CFG_PRIO_MAX; OS_PendListInit(&p_mutex->PendList); /* Initialize the waiting list */ #if OS_CFG_DBG_EN > 0u OS_MutexDbgListAdd(p_mutex); #endif OSMutexQty++; CPU_CRITICAL_EXIT(); *p_err = OS_ERR_NONE; } /*$PAGE*/ /* ************************************************************************************************************************ * DELETE A MUTEX * * Description: This function deletes a mutex and readies all tasks pending on the mutex. * * Arguments : p_mutex is a pointer to the mutex to delete * * opt determines delete options as follows: * * OS_OPT_DEL_NO_PEND Delete mutex ONLY if no task pending * OS_OPT_DEL_ALWAYS Deletes the mutex even if tasks are waiting. * In this case, all the tasks pending will be readied. * * p_err is a pointer to a variable that will contain an error code returned by this function. * * OS_ERR_NONE The call was successful and the mutex was deleted * OS_ERR_DEL_ISR If you attempted to delete the mutex from an ISR * OS_ERR_OBJ_PTR_NULL If 'p_mutex' is a NULL pointer. * OS_ERR_OBJ_TYPE If 'p_mutex' is not pointing to a mutex * OS_ERR_OPT_INVALID An invalid option was specified * OS_ERR_STATE_INVALID Task is in an invalid state * OS_ERR_TASK_WAITING One or more tasks were waiting on the mutex * * Returns : == 0 if no tasks were waiting on the mutex, or upon error. * > 0 if one or more tasks waiting on the mutex are now readied and informed. * * Note(s) : 1) This function must be used with care. Tasks that would normally expect the presence of the mutex MUST * check the return code of OSMutexPend(). * * 2) OSMutexAccept() callers will not know that the intended mutex has been deleted. * * 3) Because ALL tasks pending on the mutex will be readied, you MUST be careful in applications where the * mutex is used for mutual exclusion because the resource(s) will no longer be guarded by the mutex. ************************************************************************************************************************ */ #if OS_CFG_MUTEX_DEL_EN > 0u OS_OBJ_QTY OSMutexDel (OS_MUTEX *p_mutex, OS_OPT opt, OS_ERR *p_err) { OS_OBJ_QTY cnt; OS_OBJ_QTY nbr_tasks; OS_PEND_DATA *p_pend_data; OS_PEND_LIST *p_pend_list; OS_TCB *p_tcb; OS_TCB *p_tcb_owner; CPU_TS ts; CPU_SR_ALLOC(); #ifdef OS_SAFETY_CRITICAL if (p_err == (OS_ERR *)0) { OS_SAFETY_CRITICAL_EXCEPTION(); return ((OS_OBJ_QTY)0); } #endif #if OS_CFG_CALLED_FROM_ISR_CHK_EN > 0u if (OSIntNestingCtr > (OS_NESTING_CTR)0) { /* Not allowed to delete a mutex from an ISR */ *p_err = OS_ERR_DEL_ISR; return ((OS_OBJ_QTY)0); } #endif #if OS_CFG_ARG_CHK_EN > 0u if (p_mutex == (OS_MUTEX *)0) { /* Validate pointer to mutex */ *p_err = OS_ERR_OBJ_PTR_NULL; return ((OS_OBJ_QTY)0); } #endif #if OS_CFG_OBJ_TYPE_CHK_EN > 0u if (p_mutex->Type != OS_OBJ_TYPE_MUTEX) { /* Make sure mutex was created */ *p_err = OS_ERR_OBJ_TYPE; return ((OS_OBJ_QTY)0); } #endif OS_CRITICAL_ENTER(); p_pend_list = &p_mutex->PendList; cnt = p_pend_list->NbrEntries; nbr_tasks = cnt; switch (opt) { case OS_OPT_DEL_NO_PEND: /* Delete mutex only if no task waiting */ if (nbr_tasks == (OS_OBJ_QTY)0) { #if OS_CFG_DBG_EN > 0u OS_MutexDbgListRemove(p_mutex); #endif OSMutexQty--; OS_MutexClr(p_mutex); OS_CRITICAL_EXIT(); *p_err = OS_ERR_NONE; } else { OS_CRITICAL_EXIT(); *p_err = OS_ERR_TASK_WAITING; } break; case OS_OPT_DEL_ALWAYS: /* Always delete the mutex */ p_tcb_owner = p_mutex->OwnerTCBPtr; /* Did we had to change the prio of owner? */ if ((p_tcb_owner != (OS_TCB *)0) && (p_tcb_owner->Prio != p_mutex->OwnerOriginalPrio)) { switch (p_tcb_owner->TaskState) { /* yes */ case OS_TASK_STATE_RDY: OS_RdyListRemove(p_tcb_owner); p_tcb_owner->Prio = p_mutex->OwnerOriginalPrio; /* Lower owner's prio back */ OS_PrioInsert(p_tcb_owner->Prio); OS_RdyListInsertTail(p_tcb_owner); /* Insert owner in ready list at new prio */ break; case OS_TASK_STATE_DLY: case OS_TASK_STATE_SUSPENDED: case OS_TASK_STATE_DLY_SUSPENDED: p_tcb_owner->Prio = p_mutex->OwnerOriginalPrio; /* Not in any pend list, change the prio */ break; case OS_TASK_STATE_PEND: case OS_TASK_STATE_PEND_TIMEOUT: case OS_TASK_STATE_PEND_SUSPENDED: case OS_TASK_STATE_PEND_TIMEOUT_SUSPENDED: OS_PendListChangePrio(p_tcb_owner, /* Owner is pending on another object */ p_mutex->OwnerOriginalPrio); break; default: OS_CRITICAL_EXIT(); *p_err = OS_ERR_STATE_INVALID; return ((OS_OBJ_QTY)0); } } ts = OS_TS_GET(); /* Get timestamp */ while (cnt > 0u) { /* Remove all tasks from the pend list */ p_pend_data = p_pend_list->HeadPtr; p_tcb = p_pend_data->TCBPtr; OS_PendObjDel((OS_PEND_OBJ *)((void *)p_mutex), p_tcb, ts); cnt--; } #if OS_CFG_DBG_EN > 0u OS_MutexDbgListRemove(p_mutex); #endif OSMutexQty--; OS_MutexClr(p_mutex); OS_CRITICAL_EXIT_NO_SCHED(); OSSched(); /* Find highest priority task ready to run */ *p_err = OS_ERR_NONE; break; default: OS_CRITICAL_EXIT(); *p_err = OS_ERR_OPT_INVALID; break; } return (nbr_tasks); } #endif /*$PAGE*/ /* ************************************************************************************************************************ * PEND ON MUTEX * * Description: This function waits for a mutex. * * Arguments : p_mutex is a pointer to the mutex * * timeout is an optional timeout period (in clock ticks). If non-zero, your task will wait for the * resource up to the amount of time (in 'ticks') specified by this argument. If you specify * 0, however, your task will wait forever at the specified mutex or, until the resource * becomes available. * * opt determines whether the user wants to block if the mutex is not available or not: * * OS_OPT_PEND_BLOCKING * OS_OPT_PEND_NON_BLOCKING * * p_ts is a pointer to a variable that will receive the timestamp of when the mutex was posted or * pend aborted or the mutex deleted. If you pass a NULL pointer (i.e. (CPU_TS *)0) then you * will not get the timestamp. In other words, passing a NULL pointer is valid and indicates * that you don't need the timestamp. * * p_err is a pointer to a variable that will contain an error code returned by this function. * * OS_ERR_NONE The call was successful and your task owns the resource * OS_ERR_MUTEX_OWNER If calling task already owns the mutex * OS_ERR_OBJ_DEL If 'p_mutex' was deleted * OS_ERR_OBJ_PTR_NULL If 'p_mutex' is a NULL pointer. * OS_ERR_OBJ_TYPE If 'p_mutex' is not pointing at a mutex * OS_ERR_OPT_INVALID If you didn't specify a valid option * OS_ERR_PEND_ABORT If the pend was aborted by another task * OS_ERR_PEND_ISR If you called this function from an ISR and the result * would lead to a suspension. * OS_ERR_PEND_WOULD_BLOCK If you specified non-blocking but the mutex was not * available. * OS_ERR_SCHED_LOCKED If you called this function when the scheduler is locked * OS_ERR_STATE_INVALID If the task is in an invalid state * OS_ERR_STATUS_INVALID If the pend status has an invalid value * OS_ERR_TIMEOUT The mutex was not received within the specified timeout. * * Returns : none ************************************************************************************************************************ */ void OSMutexPend (OS_MUTEX *p_mutex, OS_TICK timeout, OS_OPT opt, CPU_TS *p_ts, OS_ERR *p_err) { OS_PEND_DATA pend_data; OS_TCB *p_tcb; CPU_SR_ALLOC(); #ifdef OS_SAFETY_CRITICAL if (p_err == (OS_ERR *)0) { OS_SAFETY_CRITICAL_EXCEPTION(); return; } #endif #if OS_CFG_CALLED_FROM_ISR_CHK_EN > 0u if (OSIntNestingCtr > (OS_NESTING_CTR)0) { /* Not allowed to call from an ISR */ *p_err = OS_ERR_PEND_ISR; return; } #endif #if OS_CFG_ARG_CHK_EN > 0u if (p_mutex == (OS_MUTEX *)0) { /* Validate arguments */ *p_err = OS_ERR_OBJ_PTR_NULL; return; } switch (opt) { case OS_OPT_PEND_BLOCKING: case OS_OPT_PEND_NON_BLOCKING: break; default: *p_err = OS_ERR_OPT_INVALID; return; } #endif #if OS_CFG_OBJ_TYPE_CHK_EN > 0u if (p_mutex->Type != OS_OBJ_TYPE_MUTEX) { /* Make sure mutex was created */ *p_err = OS_ERR_OBJ_TYPE; return; } #endif if (p_ts != (CPU_TS *)0) { *p_ts = (CPU_TS )0; /* Initialize the returned timestamp */ } CPU_CRITICAL_ENTER(); if (p_mutex->OwnerNestingCtr == (OS_NESTING_CTR)0) { /* Resource available? */ p_mutex->OwnerTCBPtr = OSTCBCurPtr; /* Yes, caller may proceed */ p_mutex->OwnerOriginalPrio = OSTCBCurPtr->Prio; p_mutex->OwnerNestingCtr = (OS_NESTING_CTR)1; if (p_ts != (CPU_TS *)0) { *p_ts = p_mutex->TS; } CPU_CRITICAL_EXIT(); *p_err = OS_ERR_NONE; return; } if (OSTCBCurPtr == p_mutex->OwnerTCBPtr) { /* See if current task is already the owner of the mutex */ p_mutex->OwnerNestingCtr++; if (p_ts != (CPU_TS *)0) { *p_ts = p_mutex->TS; } CPU_CRITICAL_EXIT(); *p_err = OS_ERR_MUTEX_OWNER; /* Indicate that current task already owns the mutex */ return; } if ((opt & OS_OPT_PEND_NON_BLOCKING) != (OS_OPT)0) { /* Caller wants to block if not available? */ CPU_CRITICAL_EXIT(); *p_err = OS_ERR_PEND_WOULD_BLOCK; /* No */ return; } else { if (OSSchedLockNestingCtr > (OS_NESTING_CTR)0) { /* Can't pend when the scheduler is locked */ CPU_CRITICAL_EXIT(); *p_err = OS_ERR_SCHED_LOCKED; return; } } OS_CRITICAL_ENTER_CPU_CRITICAL_EXIT(); /* Lock the scheduler/re-enable interrupts */ p_tcb = p_mutex->OwnerTCBPtr; /* Point to the TCB of the Mutex owner */ if (p_tcb->Prio > OSTCBCurPtr->Prio) { /* See if mutex owner has a lower priority than current */ switch (p_tcb->TaskState) { case OS_TASK_STATE_RDY: OS_RdyListRemove(p_tcb); /* Remove from ready list at current priority */ p_tcb->Prio = OSTCBCurPtr->Prio; /* Raise owner's priority */ OS_PrioInsert(p_tcb->Prio); OS_RdyListInsertHead(p_tcb); /* Insert in ready list at new priority */ break; case OS_TASK_STATE_DLY: case OS_TASK_STATE_DLY_SUSPENDED: case OS_TASK_STATE_SUSPENDED: p_tcb->Prio = OSTCBCurPtr->Prio; /* Only need to raise the owner's priority */ break; case OS_TASK_STATE_PEND: /* Change the position of the task in the wait list */ case OS_TASK_STATE_PEND_TIMEOUT: case OS_TASK_STATE_PEND_SUSPENDED: case OS_TASK_STATE_PEND_TIMEOUT_SUSPENDED: OS_PendListChangePrio(p_tcb, OSTCBCurPtr->Prio); break; default: OS_CRITICAL_EXIT(); *p_err = OS_ERR_STATE_INVALID; return; } } OS_Pend(&pend_data, /* Block task pending on Mutex */ (OS_PEND_OBJ *)((void *)p_mutex), OS_TASK_PEND_ON_MUTEX, timeout); OS_CRITICAL_EXIT_NO_SCHED(); OSSched(); /* Find the next highest priority task ready to run */ CPU_CRITICAL_ENTER(); switch (OSTCBCurPtr->PendStatus) { case OS_STATUS_PEND_OK: /* We got the mutex */ if (p_ts != (CPU_TS *)0) { *p_ts = OSTCBCurPtr->TS; } *p_err = OS_ERR_NONE; break; case OS_STATUS_PEND_ABORT: /* Indicate that we aborted */ if (p_ts != (CPU_TS *)0) { *p_ts = OSTCBCurPtr->TS; } *p_err = OS_ERR_PEND_ABORT; break; case OS_STATUS_PEND_TIMEOUT: /* Indicate that we didn't get mutex within timeout */ if (p_ts != (CPU_TS *)0) { *p_ts = (CPU_TS )0; } *p_err = OS_ERR_TIMEOUT; break; case OS_STATUS_PEND_DEL: /* Indicate that object pended on has been deleted */ if (p_ts != (CPU_TS *)0) { *p_ts = OSTCBCurPtr->TS; } *p_err = OS_ERR_OBJ_DEL; break; default: *p_err = OS_ERR_STATUS_INVALID; break; } CPU_CRITICAL_EXIT(); } /*$PAGE*/ /* ************************************************************************************************************************ * ABORT WAITING ON A MUTEX * * Description: This function aborts & readies any tasks currently waiting on a mutex. This function should be used * to fault-abort the wait on the mutex, rather than to normally signal the mutex via OSMutexPost(). * * Arguments : p_mutex is a pointer to the mutex * * opt determines the type of ABORT performed: * * OS_OPT_PEND_ABORT_1 ABORT wait for a single task (HPT) waiting on the mutex * OS_OPT_PEND_ABORT_ALL ABORT wait for ALL tasks that are waiting on the mutex * OS_OPT_POST_NO_SCHED Do not call the scheduler * * p_err is a pointer to a variable that will contain an error code returned by this function. * * OS_ERR_NONE At least one task waiting on the mutex was readied and * informed of the aborted wait; check return value for the * number of tasks whose wait on the mutex was aborted. * OS_ERR_OBJ_PTR_NULL If 'p_mutex' is a NULL pointer. * OS_ERR_OBJ_TYPE If 'p_mutex' is not pointing at a mutex * OS_ERR_OPT_INVALID If you specified an invalid option * OS_ERR_PEND_ABORT_ISR If you attempted to call this function from an ISR * OS_ERR_PEND_ABORT_NONE No task were pending * * Returns : == 0 if no tasks were waiting on the mutex, or upon error. * > 0 if one or more tasks waiting on the mutex are now readied and informed. ************************************************************************************************************************ */ #if OS_CFG_MUTEX_PEND_ABORT_EN > 0u OS_OBJ_QTY OSMutexPendAbort (OS_MUTEX *p_mutex, OS_OPT opt, OS_ERR *p_err) { OS_PEND_LIST *p_pend_list; OS_TCB *p_tcb; CPU_TS ts; OS_OBJ_QTY nbr_tasks; CPU_SR_ALLOC(); #ifdef OS_SAFETY_CRITICAL if (p_err == (OS_ERR *)0) { OS_SAFETY_CRITICAL_EXCEPTION(); return ((OS_OBJ_QTY)0u); } #endif #if OS_CFG_CALLED_FROM_ISR_CHK_EN > 0u if (OSIntNestingCtr > (OS_NESTING_CTR)0u) { /* Not allowed to Pend Abort from an ISR */ *p_err = OS_ERR_PEND_ABORT_ISR; return ((OS_OBJ_QTY)0u); } #endif #if OS_CFG_ARG_CHK_EN > 0u if (p_mutex == (OS_MUTEX *)0) { /* Validate 'p_mutex' */ *p_err = OS_ERR_OBJ_PTR_NULL; return ((OS_OBJ_QTY)0u); } switch (opt) { /* Validate 'opt' */ case OS_OPT_PEND_ABORT_1: case OS_OPT_PEND_ABORT_ALL: break; default: *p_err = OS_ERR_OPT_INVALID; return ((OS_OBJ_QTY)0u); } #endif #if OS_CFG_OBJ_TYPE_CHK_EN > 0u if (p_mutex->Type != OS_OBJ_TYPE_MUTEX) { /* Make sure mutex was created */ *p_err = OS_ERR_OBJ_TYPE; return ((OS_OBJ_QTY)0u); } #endif CPU_CRITICAL_ENTER(); p_pend_list = &p_mutex->PendList; if (p_pend_list->NbrEntries == (OS_OBJ_QTY)0u) { /* Any task waiting on mutex? */ CPU_CRITICAL_EXIT(); /* No */ *p_err = OS_ERR_PEND_ABORT_NONE; return ((OS_OBJ_QTY)0u); } OS_CRITICAL_ENTER_CPU_CRITICAL_EXIT(); nbr_tasks = 0u; ts = OS_TS_GET(); /* Get local time stamp so all tasks get the same time */ while (p_pend_list->NbrEntries > (OS_OBJ_QTY)0u) { p_tcb = p_pend_list->HeadPtr->TCBPtr; OS_PendAbort((OS_PEND_OBJ *)((void *)p_mutex), p_tcb, ts); nbr_tasks++; if (opt != OS_OPT_PEND_ABORT_ALL) { /* Pend abort all tasks waiting? */ break; /* No */ } } OS_CRITICAL_EXIT_NO_SCHED(); if ((opt & OS_OPT_POST_NO_SCHED) == (OS_OPT)0u) { OSSched(); /* Run the scheduler */ } *p_err = OS_ERR_NONE; return (nbr_tasks); } #endif /*$PAGE*/ /* ************************************************************************************************************************ * POST TO A MUTEX * * Description: This function signals a mutex * * Arguments : p_mutex is a pointer to the mutex * * opt is an option you can specify to alter the behavior of the post. The choices are: * * OS_OPT_POST_NONE No special option selected * OS_OPT_POST_NO_SCHED If you don't want the scheduler to be called after the post. * * p_err is a pointer to a variable that will contain an error code returned by this function. * * OS_ERR_NONE The call was successful and the mutex was signaled. * OS_ERR_MUTEX_NESTING Mutex owner nested its use of the mutex * OS_ERR_MUTEX_NOT_OWNER If the task posting is not the Mutex owner * OS_ERR_OBJ_PTR_NULL If 'p_mutex' is a NULL pointer. * OS_ERR_OBJ_TYPE If 'p_mutex' is not pointing at a mutex * OS_ERR_POST_ISR If you attempted to post from an ISR * * Returns : none ************************************************************************************************************************ */ void OSMutexPost (OS_MUTEX *p_mutex, OS_OPT opt, OS_ERR *p_err) { OS_PEND_LIST *p_pend_list; OS_TCB *p_tcb; CPU_TS ts; CPU_SR_ALLOC(); #ifdef OS_SAFETY_CRITICAL if (p_err == (OS_ERR *)0) { OS_SAFETY_CRITICAL_EXCEPTION(); return; } #endif #if OS_CFG_CALLED_FROM_ISR_CHK_EN > 0u if (OSIntNestingCtr > (OS_NESTING_CTR)0) { /* Not allowed to call from an ISR */ *p_err = OS_ERR_POST_ISR; return; } #endif #if OS_CFG_ARG_CHK_EN > 0u if (p_mutex == (OS_MUTEX *)0) { /* Validate 'p_mutex' */ *p_err = OS_ERR_OBJ_PTR_NULL; return; } #endif #if OS_CFG_OBJ_TYPE_CHK_EN > 0u if (p_mutex->Type != OS_OBJ_TYPE_MUTEX) { /* Make sure mutex was created */ *p_err = OS_ERR_OBJ_TYPE; return; } #endif CPU_CRITICAL_ENTER(); if (OSTCBCurPtr != p_mutex->OwnerTCBPtr) { /* Make sure the mutex owner is releasing the mutex */ CPU_CRITICAL_EXIT(); *p_err = OS_ERR_MUTEX_NOT_OWNER; return; } OS_CRITICAL_ENTER_CPU_CRITICAL_EXIT(); ts = OS_TS_GET(); /* Get timestamp */ p_mutex->TS = ts; p_mutex->OwnerNestingCtr--; /* Decrement owner's nesting counter */ if (p_mutex->OwnerNestingCtr > (OS_NESTING_CTR)0) { /* Are we done with all nestings? */ OS_CRITICAL_EXIT(); /* No */ *p_err = OS_ERR_MUTEX_NESTING; return; } p_pend_list = &p_mutex->PendList; if (p_pend_list->NbrEntries == (OS_OBJ_QTY)0) { /* Any task waiting on mutex? */ p_mutex->OwnerTCBPtr = (OS_TCB *)0; /* No */ p_mutex->OwnerNestingCtr = (OS_NESTING_CTR)0; OS_CRITICAL_EXIT(); *p_err = OS_ERR_NONE; return; } /* Yes */ if (OSTCBCurPtr->Prio != p_mutex->OwnerOriginalPrio) { OS_RdyListRemove(OSTCBCurPtr); OSTCBCurPtr->Prio = p_mutex->OwnerOriginalPrio; /* Lower owner's priority back to its original one */ OS_PrioInsert(OSTCBCurPtr->Prio); OS_RdyListInsertTail(OSTCBCurPtr); /* Insert owner in ready list at new priority */ OSPrioCur = OSTCBCurPtr->Prio; } /* Get TCB from head of pend list */ p_tcb = p_pend_list->HeadPtr->TCBPtr; p_mutex->OwnerTCBPtr = p_tcb; /* Give mutex to new owner */ p_mutex->OwnerOriginalPrio = p_tcb->Prio; p_mutex->OwnerNestingCtr = (OS_NESTING_CTR)1; /* Post to mutex */ OS_Post((OS_PEND_OBJ *)((void *)p_mutex), (OS_TCB *)p_tcb, (void *)0, (OS_MSG_SIZE )0, (CPU_TS )ts); OS_CRITICAL_EXIT_NO_SCHED(); if ((opt & OS_OPT_POST_NO_SCHED) == (OS_OPT)0) { OSSched(); /* Run the scheduler */ } *p_err = OS_ERR_NONE; } /*$PAGE*/ /* ************************************************************************************************************************ * CLEAR THE CONTENTS OF A MUTEX * * Description: This function is called by OSMutexDel() to clear the contents of a mutex * * Argument(s): p_mutex is a pointer to the mutex to clear * ------- * * Returns : none * * Note(s) : This function is INTERNAL to uC/OS-III and your application should not call it. ************************************************************************************************************************ */ void OS_MutexClr (OS_MUTEX *p_mutex) { p_mutex->Type = OS_OBJ_TYPE_NONE; /* Mark the data structure as a NONE */ p_mutex->NamePtr = (CPU_CHAR *)((void *)"?MUTEX"); p_mutex->OwnerTCBPtr = (OS_TCB *)0; p_mutex->OwnerNestingCtr = (OS_NESTING_CTR)0; p_mutex->TS = (CPU_TS )0; p_mutex->OwnerOriginalPrio = OS_CFG_PRIO_MAX; OS_PendListInit(&p_mutex->PendList); /* Initialize the waiting list */ } /*$PAGE*/ /* ************************************************************************************************************************ * ADD/REMOVE MUTEX TO/FROM DEBUG LIST * * Description: These functions are called by uC/OS-III to add or remove a mutex to/from the debug list. * * Arguments : p_mutex is a pointer to the mutex to add/remove * * Returns : none * * Note(s) : These functions are INTERNAL to uC/OS-III and your application should not call it. ************************************************************************************************************************ */ #if OS_CFG_DBG_EN > 0u void OS_MutexDbgListAdd (OS_MUTEX *p_mutex) { p_mutex->DbgNamePtr = (CPU_CHAR *)((void *)" "); p_mutex->DbgPrevPtr = (OS_MUTEX *)0; if (OSMutexDbgListPtr == (OS_MUTEX *)0) { p_mutex->DbgNextPtr = (OS_MUTEX *)0; } else { p_mutex->DbgNextPtr = OSMutexDbgListPtr; OSMutexDbgListPtr->DbgPrevPtr = p_mutex; } OSMutexDbgListPtr = p_mutex; } void OS_MutexDbgListRemove (OS_MUTEX *p_mutex) { OS_MUTEX *p_mutex_next; OS_MUTEX *p_mutex_prev; p_mutex_prev = p_mutex->DbgPrevPtr; p_mutex_next = p_mutex->DbgNextPtr; if (p_mutex_prev == (OS_MUTEX *)0) { OSMutexDbgListPtr = p_mutex_next; if (p_mutex_next != (OS_MUTEX *)0) { p_mutex_next->DbgPrevPtr = (OS_MUTEX *)0; } p_mutex->DbgNextPtr = (OS_MUTEX *)0; } else if (p_mutex_next == (OS_MUTEX *)0) { p_mutex_prev->DbgNextPtr = (OS_MUTEX *)0; p_mutex->DbgPrevPtr = (OS_MUTEX *)0; } else { p_mutex_prev->DbgNextPtr = p_mutex_next; p_mutex_next->DbgPrevPtr = p_mutex_prev; p_mutex->DbgNextPtr = (OS_MUTEX *)0; p_mutex->DbgPrevPtr = (OS_MUTEX *)0; } } #endif /*$PAGE*/ /* ************************************************************************************************************************ * MUTEX INITIALIZATION * * Description: This function is called by OSInit() to initialize the mutex management. * * Argument(s): p_err is a pointer to a variable that will contain an error code returned by this function. * * OS_ERR_NONE the call was successful * * Returns : none * * Note(s) : 1) This function is INTERNAL to uC/OS-III and your application MUST NOT call it. ************************************************************************************************************************ */ void OS_MutexInit (OS_ERR *p_err) { #ifdef OS_SAFETY_CRITICAL if (p_err == (OS_ERR *)0) { OS_SAFETY_CRITICAL_EXCEPTION(); return; } #endif #if OS_CFG_DBG_EN > 0u OSMutexDbgListPtr = (OS_MUTEX *)0; #endif OSMutexQty = (OS_OBJ_QTY)0; *p_err = OS_ERR_NONE; } #endif /* OS_CFG_MUTEX_EN */