+
−/*************************************************************************/
+
−/*                                                                       */
+
−/*               Copyright Mentor Graphics Corporation 2002              */
+
−/*                         All Rights Reserved.                          */
+
−/*                                                                       */
+
−/* THIS WORK CONTAINS TRADE SECRET AND PROPRIETARY INFORMATION WHICH IS  */
+
−/* THE PROPERTY OF MENTOR GRAPHICS CORPORATION OR ITS LICENSORS AND IS   */
+
−/* SUBJECT TO LICENSE TERMS.                                             */
+
−/*                                                                       */
+
−/*************************************************************************/
+
−
+
−/*************************************************************************/
+
−/*                                                                       */
+
−/* FILE NAME                                               VERSION       */
+
−/*                                                                       */
+
−/*      dmc.c                                          Nucleus PLUS 1.14 */
+
−/*                                                                       */
+
−/* COMPONENT                                                             */
+
−/*                                                                       */
+
−/*      DM - Dynamic Memory Management                                   */
+
−/*                                                                       */
+
−/* DESCRIPTION                                                           */
+
−/*                                                                       */
+
−/*      This file contains the core routines for the Dynamic Memory      */
+
−/*      Management component.                                            */
+
−/*                                                                       */
+
−/* DATA STRUCTURES                                                       */
+
−/*                                                                       */
+
−/*      None                                                             */
+
−/*                                                                       */
+
−/* FUNCTIONS                                                             */
+
−/*                                                                       */
+
−/*      DMC_Create_Memory_Pool              Create a dynamic memory pool */
+
−/*      DMC_Delete_Memory_Pool              Delete a dynamic memory pool */
+
−/*      DMC_Allocate_Memory                 Allocate a memory block from */
+
−/*                                            a dynamic memory pool      */
+
−/*      DMC_Deallocate_Memory               Deallocate a memory block    */
+
−/*                                            from a dynamic memory pool */
+
−/*      DMC_Cleanup                         Cleanup on timeout or a      */
+
−/*                                            terminate condition        */
+
−/*                                                                       */
+
−/* DEPENDENCIES                                                          */
+
−/*                                                                       */
+
−/*      cs_extr.h                           Common Service functions     */
+
−/*      tc_extr.h                           Thread Control functions     */
+
−/*      dm_extr.h                           Partition functions          */
+
−/*      hi_extr.h                           History functions            */
+
−/*                                                                       */
+
−/* HISTORY                                                               */
+
−/*                                                                       */
+
−/*      DATE                    REMARKS                                  */
+
−/*                                                                       */
+
−/*      03-01-1993      Created initial version 1.0                      */
+
−/*      04-19-1993      Verified version 1.0                             */
+
−/*      08-09-1993      Corrected pointer retrieval                      */
+
−/*                      loop, resulting in version 1.0a                  */
+
−/*      08-09-1993      Verified version 1.0a                            */
+
−/*      03-01-1994      Moved non-core functions into                    */
+
−/*                      supplemental files, changed                      */
+
−/*                      function interfaces to match                     */
+
−/*                      those in prototype, added                        */
+
−/*                      register options, changed                        */
+
−/*                      protection logic to reduce                       */
+
−/*                      overhead, resulting in                           */
+
−/*                      version 1.1                                      */
+
−/*                                                                       */
+
−/*      03-18-1994      Verified version 1.1                             */
+
−/*      04-17-1996      updated to version 1.2                           */
+
−/*      03-24-1998      Released version 1.3.                            */
+
−/*      03-26-1999      Released 1.11m (new release                      */
+
−/*                        numbering scheme)                              */
+
−/*      04-17-2002      Released version 1.13m                           */
+
−/*      11-07-2002      Released version 1.14                            */
+
−/*************************************************************************/
+
−#define         NU_SOURCE_FILE
+
−
+
−
+
−#include        "cs_extr.h"                 /* Common service functions  */
+
−#include        "tc_extr.h"                 /* Thread control functions  */
+
−#include        "dm_extr.h"                 /* Dynamic memory functions  */
+
−#include        "hi_extr.h"                 /* History functions         */
+
−#include        "profiler.h"                /* ProView interface         */
+
−
+
−
+
−/* Define external inner-component global data references.  */
+
−
+
−extern CS_NODE         *DMD_Created_Pools_List;
+
−extern UNSIGNED         DMD_Total_Pools;
+
−extern TC_PROTECT       DMD_List_Protect;
+
−
+
−
+
−/* Define internal component function prototypes.  */
+
−
+
−VOID    DMC_Cleanup(VOID *information);
+
−
+
−
+
−/*************************************************************************/
+
−/*                                                                       */
+
−/* FUNCTION                                                              */
+
−/*                                                                       */
+
−/*      DMC_Create_Memory_Pool                                           */
+
−/*                                                                       */
+
−/* DESCRIPTION                                                           */
+
−/*                                                                       */
+
−/*      This function creates a dynamic memory pool and then places it   */
+
−/*      on the list of created dynamic memory pools.                     */
+
−/*                                                                       */
+
−/* CALLED BY                                                             */
+
−/*                                                                       */
+
−/*      Application                                                      */
+
−/*      DMCE_Create_Memory_Pool             Error checking shell         */
+
−/*                                                                       */
+
−/* CALLS                                                                 */
+
−/*                                                                       */
+
−/*      CSC_Place_On_List                   Add node to linked-list      */
+
−/*      [HIC_Make_History_Entry]            Make entry in history log    */
+
−/*      [TCT_Check_Stack]                   Stack checking function      */
+
−/*      TCT_Protect                         Data structure protect       */
+
−/*      TCT_Unprotect                       Un-protect data structure    */
+
−/*                                                                       */
+
−/* INPUTS                                                                */
+
−/*                                                                       */
+
−/*      pool_ptr                            Memory pool control block    */
+
−/*                                            pointer                    */
+
−/*      name                                Memory pool name             */
+
−/*      start_address                       Starting address of the pool */
+
−/*      pool_size                           Number of bytes in the pool  */
+
−/*      min_allocation                      Minimum allocation size      */
+
−/*      suspend_type                        Suspension type              */
+
−/*                                                                       */
+
−/* OUTPUTS                                                               */
+
−/*                                                                       */
+
−/*      NU_SUCCESS                                                       */
+
−/*                                                                       */
+
−/* HISTORY                                                               */
+
−/*                                                                       */
+
−/*         DATE                    REMARKS                               */
+
−/*                                                                       */
+
−/*      03-01-1993      Created initial version 1.0                      */
+
−/*      04-19-1993      Verified version 1.0                             */
+
−/*      03-01-1994      Changed function interfaces to                   */
+
−/*                      match those in prototype,                        */
+
−/*                      added register options,                          */
+
−/*                      resulting in version 1.1                         */
+
−/*                                                                       */
+
−/*      03-18-1994      Verified version 1.1                             */
+
−/*                                                                       */
+
−/*************************************************************************/
+
−STATUS  DMC_Create_Memory_Pool(NU_MEMORY_POOL *pool_ptr, CHAR *name,
+
−                        VOID *start_address, UNSIGNED pool_size,
+
−                        UNSIGNED min_allocation, OPTION suspend_type)
+
−{
+
−
+
−R1 DM_PCB      *pool;                       /* Pool control block ptr    */
+
−INT             i;                          /* Working index variable    */
+
−DM_HEADER      *header_ptr;                 /* Partition block header ptr*/
+
−NU_SUPERV_USER_VARIABLES
+
−
+
−    /* Switch to supervisor mode */
+
−    NU_SUPERVISOR_MODE();
+
−
+
−    /* Move input pool pointer into internal pointer.  */
+
−    pool =  (DM_PCB *) pool_ptr;
+
−
+
−
+
−#ifdef  NU_ENABLE_STACK_CHECK
+
−
+
−    /* Call stack checking function to check for an overflow condition.  */
+
−    TCT_Check_Stack();
+
−
+
−#endif
+
−
+
−#ifdef  NU_ENABLE_HISTORY
+
−
+
−    /* Make an entry that corresponds to this function in the system history
+
−       log.  */
+
−    HIC_Make_History_Entry(NU_CREATE_MEMORY_POOL_ID, (UNSIGNED) pool,
+
−                        (UNSIGNED) start_address, (UNSIGNED) pool_size);
+
−
+
−#endif
+
−
+
−    /* First, clear the partition pool ID just in case it is an old
+
−       pool control block.  */
+
−    pool -> dm_id =             0;
+
−
+
−    /* Fill in the partition pool name.  */
+
−    for (i = 0; i < NU_MAX_NAME; i++)
+
−        pool -> dm_name[i] =  name[i];
+
−
+
−    /* Convert the pool's size into something that is evenly divisible by
+
−       the sizeof an UNSIGNED data element.  */
+
−    pool_size =  (pool_size/sizeof(UNSIGNED)) * sizeof(UNSIGNED);
+
−
+
−    /* Save the starting address and size parameters in the dynamic memory
+
−       control block.  */
+
−    pool -> dm_start_address =   start_address;
+
−    pool -> dm_pool_size =       pool_size;
+
−    pool -> dm_min_allocation =
+
−                ((min_allocation + sizeof(UNSIGNED) - 1)/sizeof(UNSIGNED)) *
+
−                                                              sizeof(UNSIGNED);
+
−
+
−    /* Setup the dynamic memory pool suspension type.  */
+
−    if (suspend_type == NU_FIFO)
+
−
+
−        /* FIFO suspension is selected, setup the flag accordingly.  */
+
−        pool -> dm_fifo_suspend =  NU_TRUE;
+
−    else
+
−
+
−        /* Priority suspension is selected.  */
+
−        pool -> dm_fifo_suspend =  NU_FALSE;
+
−
+
−    /* Clear the suspension list pointer.  */
+
−    pool -> dm_suspension_list =  NU_NULL;
+
−
+
−    /* Clear the number of tasks waiting on the dynamic memory pool.  */
+
−    pool -> dm_tasks_waiting =  0;
+
−
+
−    /* Initialize link pointers.  */
+
−    pool -> dm_created.cs_previous =    NU_NULL;
+
−    pool -> dm_created.cs_next =        NU_NULL;
+
−
+
−    /* Build a single block that has all of the memory.  */
+
−    header_ptr =  (DM_HEADER *) start_address;
+
−
+
−    /* Initialize the memory parameters.  */
+
−    pool -> dm_available =       pool_size - (2 * DM_OVERHEAD);
+
−    pool -> dm_memory_list =     header_ptr;
+
−    pool -> dm_search_ptr =      header_ptr;
+
−
+
−    /* Build the block header.  */
+
−    header_ptr -> dm_memory_pool =  pool;
+
−    header_ptr -> dm_memory_free =  NU_TRUE;
+
−    header_ptr -> dm_next_memory =  (DM_HEADER *)
+
−           (((BYTE_PTR) header_ptr) + pool -> dm_available + DM_OVERHEAD);
+
−    header_ptr -> dm_previous_memory =  header_ptr -> dm_next_memory;
+
−
+
−    /* Build the small trailer block that prevents block merging when the
+
−       pool wraps around.  Note that the list is circular so searching can
+
−       wrap across the physical end of the memory pool.  */
+
−    header_ptr =  header_ptr -> dm_next_memory;
+
−    header_ptr -> dm_next_memory =  (DM_HEADER *) start_address;
+
−    header_ptr -> dm_previous_memory =  (DM_HEADER *) start_address;
+
−    header_ptr -> dm_memory_pool =  pool;
+
−    header_ptr -> dm_memory_free =  NU_FALSE;
+
−
+
−    /* Initialize the protection structure.  */
+
−    pool -> dm_protect.tc_tcb_pointer =  NU_NULL;
+
−
+
−    /* Protect against access to the list of created memory pools.  */
+
−    TCT_Protect(&DMD_List_Protect);
+
−
+
−    /* At this point the dynamic memory pool is completely built.  The ID can
+
−       now be set and it can be linked into the created dynamic memory
+
−       pool list. */
+
−    pool -> dm_id =  DM_DYNAMIC_ID;
+
−
+
−    /* Link the memory pool into the list of created memory pools and
+
−       increment the total number of pools in the system.  */
+
−    CSC_Place_On_List(&DMD_Created_Pools_List, &(pool -> dm_created));
+
−    DMD_Total_Pools++;
+
−
+
−#ifdef INCLUDE_PROVIEW
+
−    _RTProf_DumpMemoryPool(RT_PROF_CREATE_MEMORY_POOL,pool,RT_PROF_OK);
+
−#endif /*INCLUDE_PROVIEW*/
+
−    /* Release protection against access to the list of created memory
+
−       pools.  */
+
−    TCT_Unprotect();
+
−
+
−    /* Return to user mode */
+
−    NU_USER_MODE();
+
−
+
−    /* Return successful completion.  */
+
−    return(NU_SUCCESS);
+
−}
+
−
+
−
+
−/*************************************************************************/
+
−/*                                                                       */
+
−/* FUNCTION                                                              */
+
−/*                                                                       */
+
−/*      DMC_Delete_Memory_Pool                                           */
+
−/*                                                                       */
+
−/* DESCRIPTION                                                           */
+
−/*                                                                       */
+
−/*      This function deletes a dynamic memory pool and removes it from  */
+
−/*      the list of created memory pools.  All tasks suspended on the    */
+
−/*      memory pool are resumed with the appropriate error status.       */
+
−/*      Note that this function does not free any memory associated with */
+
−/*      either the pool area or the pool control block.                  */
+
−/*                                                                       */
+
−/* CALLED BY                                                             */
+
−/*                                                                       */
+
−/*      Application                                                      */
+
−/*      DMCE_Delete_Memory_Pool             Error checking shell         */
+
−/*                                                                       */
+
−/* CALLS                                                                 */
+
−/*                                                                       */
+
−/*      CSC_Remove_From_List                Remove node from list        */
+
−/*      [HIC_Make_History_Entry]            Make entry in history log    */
+
−/*      TCC_Resume_Task                     Resume a suspended task      */
+
−/*      [TCT_Check_Stack]                   Stack checking function      */
+
−/*      TCT_Control_To_System               Transfer control to system   */
+
−/*      TCT_Protect                         Protect created list         */
+
−/*      TCT_Set_Current_Protect             Modify current protection    */
+
−/*      TCT_System_Protect                  Setup system protection      */
+
−/*      TCT_System_Unprotect                Release system protection    */
+
−/*      TCT_Unprotect                       Release protection           */
+
−/*                                                                       */
+
−/* INPUTS                                                                */
+
−/*                                                                       */
+
−/*      pool_ptr                            Memory pool control block    */
+
−/*                                            pointer                    */
+
−/*                                                                       */
+
−/* OUTPUTS                                                               */
+
−/*                                                                       */
+
−/*      NU_SUCCESS                                                       */
+
−/*                                                                       */
+
−/* HISTORY                                                               */
+
−/*                                                                       */
+
−/*         DATE                    REMARKS                               */
+
−/*                                                                       */
+
−/*      03-01-1993      Created initial version 1.0                      */
+
−/*      04-19-1993      Verified version 1.0                             */
+
−/*      03-01-1994      Changed function interfaces to                   */
+
−/*                      match those in prototype,                        */
+
−/*                      added register options, changed                  */
+
−/*                      protection logic to reduce                       */
+
−/*                      overhead, resulting in                           */
+
−/*                      version 1.1                                      */
+
−/*                                                                       */
+
−/*      03-18-1994      Verified version 1.1                             */
+
−/*                                                                       */
+
−/*************************************************************************/
+
−STATUS  DMC_Delete_Memory_Pool(NU_MEMORY_POOL *pool_ptr)
+
−{
+
−
+
−R1 DM_PCB      *pool;                       /* Pool control block ptr    */
+
−DM_SUSPEND     *suspend_ptr;                /* Suspend block pointer     */
+
−DM_SUSPEND     *next_ptr;                   /* Next suspend block        */
+
−STATUS          preempt;                    /* Status for resume call    */
+
−NU_SUPERV_USER_VARIABLES
+
−
+
−    /* Switch to supervisor mode */
+
−    NU_SUPERVISOR_MODE();
+
−
+
−    /* Move input pool pointer into internal pointer.  */
+
−    pool =  (DM_PCB *) pool_ptr;
+
−
+
−#ifdef  NU_ENABLE_STACK_CHECK
+
−
+
−    /* Call stack checking function to check for an overflow condition.  */
+
−    TCT_Check_Stack();
+
−
+
−#endif
+
−
+
−#ifdef  NU_ENABLE_HISTORY
+
−
+
−    /* Make an entry that corresponds to this function in the system history
+
−       log.  */
+
−    HIC_Make_History_Entry(NU_DELETE_MEMORY_POOL_ID, (UNSIGNED) pool,
+
−                                        (UNSIGNED) 0, (UNSIGNED) 0);
+
−
+
−#endif
+
−
+
−    /* Protect against simultaneous access to the memory pool.  */
+
−    TCT_Protect(&(pool -> dm_protect));
+
−
+
−#ifdef INCLUDE_PROVIEW
+
−    _RTProf_DumpMemoryPool(RT_PROF_DELETE_MEMORY_POOL,pool,RT_PROF_OK);
+
−#endif /*INCLUDE_PROVIEW*/
+
−    /* Clear the memory pool ID.  */
+
−    pool -> dm_id =  0;
+
−
+
−    /* Release protection.  */
+
−    TCT_Unprotect();
+
−
+
−    /* Protect against access to the list of created memory pools.  */
+
−    TCT_Protect(&DMD_List_Protect);
+
−
+
−    /* Remove the memory pool from the list of created memory pools.  */
+
−    CSC_Remove_From_List(&DMD_Created_Pools_List, &(pool -> dm_created));
+
−
+
−    /* Decrement the total number of created memory pools.  */
+
−    DMD_Total_Pools--;
+
−
+
−    /* Pickup the suspended task pointer list.  */
+
−    suspend_ptr =  pool -> dm_suspension_list;
+
−
+
−    /* Walk the chain task(s) currently suspended on the memory pool.  */
+
−    preempt =  0;
+
−    while (suspend_ptr)
+
−    {
+
−
+
−        /* Protect against system access.  */
+
−        TCT_System_Protect();
+
−
+
−        /* Resume the suspended task.  Insure that the status returned is
+
−           NU_POOL_DELETED.  */
+
−        suspend_ptr -> dm_return_pointer =  NU_NULL;
+
−        suspend_ptr -> dm_return_status =   NU_POOL_DELETED;
+
−
+
−        /* Point to the next suspend structure in the link.  */
+
−        next_ptr =  (DM_SUSPEND *) (suspend_ptr -> dm_suspend_link.cs_next);
+
−
+
−        /* Resume the specified task.  */
+
−        preempt =  preempt |
+
−            TCC_Resume_Task((NU_TASK *) suspend_ptr -> dm_suspended_task,
+
−                                                NU_MEMORY_SUSPEND);
+
−
+
−        /* Determine if the next is the same as the current pointer.  */
+
−        if (next_ptr == pool -> dm_suspension_list)
+
−
+
−            /* Clear the suspension pointer to signal the end of the list
+
−               traversal.  */
+
−            suspend_ptr =  NU_NULL;
+
−        else
+
−
+
−            /* Move the next pointer into the suspend block pointer.  */
+
−            suspend_ptr =  next_ptr;
+
−
+
−        /* Modify current protection.  */
+
−        TCT_Set_Current_Protect(&DMD_List_Protect);
+
−
+
−        /* Clear the system protection.  */
+
−        TCT_System_Unprotect();
+
−    }
+
−
+
−    /* Determine if preemption needs to occur.  */
+
−    if (preempt)
+
−
+
−        /* Transfer control to system to facilitate preemption.  */
+
−        TCT_Control_To_System();
+
−
+
−    /* Release protection against access to the list of created memory
+
−       pools. */
+
−    TCT_Unprotect();
+
−
+
−    /* Return to user mode */
+
−    NU_USER_MODE();
+
−
+
−    /* Return a successful completion.  */
+
−    return(NU_SUCCESS);
+
−}
+
−
+
−
+
−/*************************************************************************/
+
−/*                                                                       */
+
−/* FUNCTION                                                              */
+
−/*                                                                       */
+
−/*      DMC_Allocate_Memory                                              */
+
−/*                                                                       */
+
−/* DESCRIPTION                                                           */
+
−/*                                                                       */
+
−/*      This function allocates memory from the specified dynamic memory */
+
−/*      pool.  If dynamic memory is currently available, this function   */
+
−/*      is completed immediately.  Otherwise, if there is not enough     */
+
−/*      memory currently available, task suspension is possible.         */
+
−/*                                                                       */
+
−/* CALLED BY                                                             */
+
−/*                                                                       */
+
−/*      Application                                                      */
+
−/*      DMCE_Allocate_Memory                Error checking shell         */
+
−/*                                                                       */
+
−/* CALLS                                                                 */
+
−/*                                                                       */
+
−/*      CSC_Place_On_List                   Place on suspend list        */
+
−/*      [HIC_Make_History_Entry]            Make entry in history log    */
+
−/*      TCC_Suspend_Task                    Suspend calling task         */
+
−/*      TCC_Task_Priority                   Pickup task priority         */
+
−/*      [TCT_Check_Stack]                   Stack checking function      */
+
−/*      TCT_Current_Thread                  Pickup current thread pointer*/
+
−/*      TCT_Protect                         Protect memory pool          */
+
−/*      TCT_Set_Suspend_Protect             Save suspend protection      */
+
−/*      TCT_System_Protect                  Protect system structures    */
+
−/*      TCT_Unprotect                       Release protection           */
+
−/*      TCT_Unprotect_Specific              Release specific protection  */
+
−/*                                                                       */
+
−/* INPUTS                                                                */
+
−/*                                                                       */
+
−/*      pool_ptr                            Memory pool pointer          */
+
−/*      return_pointer                      Pointer to the destination   */
+
−/*                                            memory pointer             */
+
−/*      size                                Number of bytes requested    */
+
−/*      suspend                             Suspension option if full    */
+
−/*                                                                       */
+
−/* OUTPUTS                                                               */
+
−/*                                                                       */
+
−/*      NU_SUCCESS                          If service is successful     */
+
−/*      NU_NO_MEMORY                        Memory not available         */
+
−/*      NU_TIMEOUT                          If timeout on service        */
+
−/*      NU_POOL_DELETED                     If memory pool deleted       */
+
−/*                                            during suspension          */
+
−/*                                                                       */
+
−/* HISTORY                                                               */
+
−/*                                                                       */
+
−/*         DATE                    REMARKS                               */
+
−/*                                                                       */
+
−/*      03-01-1993      Created initial version 1.0                      */
+
−/*      04-19-1993      Verified version 1.0                             */
+
−/*      03-01-1994      Changed function interfaces to                   */
+
−/*                      match those in prototype,                        */
+
−/*                      added register options, changed                  */
+
−/*                      protection logic to reduce                       */
+
−/*                      overhead, resulting in                           */
+
−/*                      version 1.1                                      */
+
−/*                                                                       */
+
−/*      03-18-1994      Verified version 1.1                             */
+
−/*                                                                       */
+
−/*************************************************************************/
+
−STATUS  DMC_Allocate_Memory(NU_MEMORY_POOL *pool_ptr, VOID **return_pointer,
+
−                                        UNSIGNED size, UNSIGNED suspend)
+
−{
+
−
+
−R1 DM_PCB      *pool;                       /* Pool control block ptr    */
+
−R2 DM_SUSPEND  *suspend_ptr;                /* Pointer to suspend block  */
+
−DM_SUSPEND      suspend_block;              /* Allocate suspension block */
+
−R4 DM_HEADER   *memory_ptr;                 /* Pointer to memory         */
+
−R3 DM_HEADER   *new_ptr;                    /* New split block pointer   */
+
−UNSIGNED        free_size;                  /* Size of block found       */
+
−TC_TCB         *task;                       /* Task pointer              */
+
−STATUS          status;                     /* Completion status         */
+
−NU_SUPERV_USER_VARIABLES
+
−
+
−    /* Switch to supervisor mode */
+
−    NU_SUPERVISOR_MODE();
+
−
+
−    /* Move input pool pointer into internal pointer.  */
+
−    pool =  (DM_PCB *) pool_ptr;
+
−
+
−
+
−#ifdef  NU_ENABLE_STACK_CHECK
+
−
+
−    /* Call stack checking function to check for an overflow condition.  */
+
−    TCT_Check_Stack();
+
−
+
−#endif
+
−
+
−#ifdef  NU_ENABLE_HISTORY
+
−
+
−    /* Make an entry that corresponds to this function in the system history
+
−       log.  */
+
−    HIC_Make_History_Entry(NU_ALLOCATE_MEMORY_ID, (UNSIGNED) pool,
+
−                                (UNSIGNED) return_pointer, (UNSIGNED) size);
+
−
+
−#endif
+
−
+
−    /* Initialize the status as successful.  */
+
−    status =  NU_SUCCESS;
+
−
+
−    /* Adjust the request to a size evenly divisible by the number of bytes
+
−       in an UNSIGNED data element.  Also, check to make sure it is of the
+
−       minimum size.  */
+
−    if (size < pool -> dm_min_allocation)
+
−
+
−        /* Change size to the minimum allocation.  */
+
−        size =  pool -> dm_min_allocation;
+
−    else
+
−
+
−        /* Insure that size is a multiple of the UNSIGNED size.  */
+
−        size =
+
−           ((size + sizeof(UNSIGNED) - 1)/sizeof(UNSIGNED)) * sizeof(UNSIGNED);
+
−
+
−    /* Protect against simultaneous access to the memory pool.  */
+
−    TCT_Protect(&(pool -> dm_protect));
+
−
+
−    /* Search the memory list for the first available block of memory that
+
−       satisfies the request.  Note that blocks are merged during the
+
−       deallocation function.  */
+
−    memory_ptr =  pool -> dm_search_ptr;
+
−    do
+
−    {
+
−
+
−        /* Determine if the block is free and if it can satisfy the request. */
+
−        if (memory_ptr -> dm_memory_free)
+
−
+
−            /* Calculate the free block size.  */
+
−            free_size =  (((BYTE_PTR) (memory_ptr -> dm_next_memory)) -
+
−                           ((BYTE_PTR) memory_ptr)) - DM_OVERHEAD;
+
−        else
+
−
+
−            /* There are no free bytes available.  */
+
−            free_size =  0;
+
−
+
−        /* Determine if the search should continue.  */
+
−        if (free_size < size)
+
−
+
−            /* Large enough block has not been found.  Move the search
+
−               pointer to the next block.  */
+
−            memory_ptr =  memory_ptr -> dm_next_memory;
+
−    } while((free_size < size) && (memory_ptr != pool -> dm_search_ptr));
+
−
+
−    /* Determine if the memory is available.  */
+
−    if (free_size >= size)
+
−    {
+
−
+
−        /* A block that satisfies the request has been found.  */
+
−
+
−        /* Determine if the block needs to be split.  */
+
−        if (free_size >= (size + DM_OVERHEAD + pool -> dm_min_allocation))
+
−        {
+
−
+
−            /* Yes, split the block.  */
+
−            new_ptr =  (DM_HEADER *) (((BYTE_PTR) memory_ptr) + size +
+
−                                                DM_OVERHEAD);
+
−
+
−            /* Mark the new block as free.  */
+
−            new_ptr -> dm_memory_free =  NU_TRUE;
+
−
+
−            /* Put the pool pointer into the new block.  */
+
−            new_ptr -> dm_memory_pool =  pool;
+
−
+
−            /* Build the necessary pointers.  */
+
−            new_ptr -> dm_previous_memory =  memory_ptr;
+
−            new_ptr -> dm_next_memory =      memory_ptr -> dm_next_memory;
+
−            (new_ptr -> dm_next_memory) -> dm_previous_memory =  new_ptr;
+
−            memory_ptr -> dm_next_memory =   new_ptr;
+
−
+
−            /* Decrement the available byte count.  */
+
−            pool -> dm_available =  pool -> dm_available - size - DM_OVERHEAD;
+
−        }
+
−        else
+
−
+
−            /* Decrement the entire free size from the available bytes
+
−               count.  */
+
−            pool -> dm_available =  pool -> dm_available - free_size;
+
−
+
−        /* Mark the allocated block as not available.  */
+
−        memory_ptr -> dm_memory_free =  NU_FALSE;
+
−
+
−        /* Should the search pointer be moved?   */
+
−        if (pool -> dm_search_ptr == memory_ptr)
+
−
+
−            /* Move the search pointer to the next free memory slot.  */
+
−            pool -> dm_search_ptr =  memory_ptr -> dm_next_memory;
+
−
+
−        /* Return a memory address to the caller.  */
+
−        *return_pointer =  (VOID *) (((BYTE_PTR) memory_ptr) + DM_OVERHEAD);
+
−#ifdef INCLUDE_PROVIEW
+
−        _RTProf_DumpMemoryPool(RT_PROF_ALLOCATE_MEMORY,pool,RT_PROF_OK);
+
−#endif /*INCLUDE_PROVIEW*/
+
−    }
+
−    else
+
−    {
+
−
+
−        /* Enough dynamic memory is not available.  Determine if suspension is
+
−           required. */
+
−        if (suspend)
+
−        {
+
−
+
−            /* Suspension is selected.  */
+
−
+
−            /* Increment the number of tasks waiting.  */
+
−            pool -> dm_tasks_waiting++;
+
−
+
−#ifdef INCLUDE_PROVIEW
+
−            _RTProf_DumpMemoryPool(RT_PROF_ALLOCATE_MEMORY,pool,RT_PROF_WAIT);
+
−#endif /*INCLUDE_PROVIEW*/
+
−            /* Setup the suspend block and suspend the calling task.  */
+
−            suspend_ptr =  &suspend_block;
+
−            suspend_ptr -> dm_memory_pool =              pool;
+
−            suspend_ptr -> dm_request_size =             size;
+
−            suspend_ptr -> dm_suspend_link.cs_next =     NU_NULL;
+
−            suspend_ptr -> dm_suspend_link.cs_previous = NU_NULL;
+
−            task =                            (TC_TCB *) TCT_Current_Thread();
+
−            suspend_ptr -> dm_suspended_task =           task;
+
−
+
−            /* Determine if priority or FIFO suspension is associated with the
+
−               memory pool.  */
+
−            if (pool -> dm_fifo_suspend)
+
−            {
+
−
+
−                /* FIFO suspension is required.  Link the suspend block into
+
−                   the list of suspended tasks on this memory pool.  */
+
−                CSC_Place_On_List((CS_NODE **)
+
−                        &(pool -> dm_suspension_list),
+
−                                        &(suspend_ptr -> dm_suspend_link));
+
−            }
+
−            else
+
−            {
+
−
+
−                /* Get the priority of the current thread so the suspend block
+
−                   can be placed in the appropriate place.  */
+
−                suspend_ptr -> dm_suspend_link.cs_priority =
+
−                                                     TCC_Task_Priority(task);
+
−
+
−                CSC_Priority_Place_On_List((CS_NODE **)
+
−                        &(pool -> dm_suspension_list),
+
−                                        &(suspend_ptr -> dm_suspend_link));
+
−            }
+
−
+
−            /* Protect against system access.  */
+
−            TCT_System_Protect();
+
−
+
−            /* Save the list protection in preparation for suspension.  */
+
−            TCT_Set_Suspend_Protect(&(pool -> dm_protect));
+
−
+
−            /* Release protection of dynamic memory pool.  */
+
−            TCT_Unprotect_Specific(&(pool -> dm_protect));
+
−
+
−            /* Finally, suspend the calling task. Note that the suspension call
+
−               automatically clears the system protection.  */
+
−            TCC_Suspend_Task((NU_TASK *) task, NU_MEMORY_SUSPEND,
+
−                                        DMC_Cleanup, suspend_ptr, suspend);
+
−
+
−            /* Pickup the return status.  */
+
−            status =            suspend_ptr -> dm_return_status;
+
−            *return_pointer =   suspend_ptr -> dm_return_pointer;
+
−        }
+
−        else
+
−        {
+
−
+
−            /* No suspension requested.  Simply return an error status.  */
+
−            status =            NU_NO_MEMORY;
+
−            *return_pointer =   NU_NULL;
+
−#ifdef INCLUDE_PROVIEW
+
−            _RTProf_DumpMemoryPool(RT_PROF_ALLOCATE_MEMORY,pool,RT_PROF_FAIL);
+
−#endif /*INCLUDE_PROVIEW*/
+
−        }
+
−    }
+
−
+
−    /* Release protection of the memory pool.  */
+
−    TCT_Unprotect();
+
−
+
−    /* Return to user mode */
+
−    NU_USER_MODE();
+
−
+
−    /* Return the completion status.  */
+
−    return(status);
+
−}
+
−
+
−
+
−/*************************************************************************/
+
−/*                                                                       */
+
−/* FUNCTION                                                              */
+
−/*                                                                       */
+
−/*      DMC_Deallocate_Memory                                            */
+
−/*                                                                       */
+
−/* DESCRIPTION                                                           */
+
−/*                                                                       */
+
−/*      This function deallocates a previously allocated dynamic memory  */
+
−/*      block.  The deallocated dynamic memory block is merged with any  */
+
−/*      adjacent neighbors.  This insures that there are no consecutive  */
+
−/*      blocks of free memory in the pool (makes the search easier!).    */
+
−/*      If there is a task waiting for dynamic memory, a determination   */
+
−/*      of whether or not the request can now be satisfied is made after */
+
−/*      the deallocation is complete.                                    */
+
−/*                                                                       */
+
−/* CALLED BY                                                             */
+
−/*                                                                       */
+
−/*      Application                                                      */
+
−/*      DMCE_Deallocate_Memory              Error checking shell         */
+
−/*                                                                       */
+
−/* CALLS                                                                 */
+
−/*                                                                       */
+
−/*      CSC_Remove_From_List                Remove from suspend list     */
+
−/*      [HIC_Make_History_Entry]            Make entry in history log    */
+
−/*      TCC_Resume_Task                     Resume a suspended task      */
+
−/*      [TCT_Check_Stack]                   Stack checking function      */
+
−/*      TCT_Control_To_System               Transfer control to system   */
+
−/*      TCT_Set_Current_Protect             Set current protection       */
+
−/*      TCT_System_Protect                  Protect system structures    */
+
−/*      TCT_System_Unprotect                Release system protection    */
+
−/*      TCT_Protect                         Protect dynamic memory pool  */
+
−/*      TCT_Unprotect                       Release protection           */
+
−/*                                                                       */
+
−/* INPUTS                                                                */
+
−/*                                                                       */
+
−/*      memory                              Pointer to dynamic memory    */
+
−/*                                                                       */
+
−/* OUTPUTS                                                               */
+
−/*                                                                       */
+
−/*      NU_SUCCESS                                                       */
+
−/*                                                                       */
+
−/* HISTORY                                                               */
+
−/*                                                                       */
+
−/*         DATE                    REMARKS                               */
+
−/*                                                                       */
+
−/*      03-01-1993      Created initial version 1.0                      */
+
−/*      04-19-1993      Verified version 1.0                             */
+
−/*      03-01-1994      Added register options, changed                  */
+
−/*                      protection logic to reduce                       */
+
−/*                      overhead, resulting in                           */
+
−/*                      version 1.1                                      */
+
−/*                                                                       */
+
−/*      03-18-1994      Verified version 1.1                             */
+
−/*                                                                       */
+
−/*************************************************************************/
+
−STATUS  DMC_Deallocate_Memory(VOID *memory)
+
−{
+
−
+
−R1 DM_PCB      *pool;                       /* Pool pointer              */
+
−R3 DM_SUSPEND  *suspend_ptr;                /* Pointer to suspend block  */
+
−R2 DM_HEADER   *header_ptr;                 /* Pointer to memory hdr     */
+
−R4 DM_HEADER   *new_ptr;                    /* New memory block pointer  */
+
−UNSIGNED        size;                       /* Suspended task request    */
+
−UNSIGNED        free_size;                  /* Amount of free bytes      */
+
−STATUS          preempt;                    /* Preemption flag           */
+
−STATUS          status;                     /* Completion status         */
+
−NU_SUPERV_USER_VARIABLES
+
−
+
−    /* Switch to supervisor mode */
+
−    NU_SUPERVISOR_MODE();
+
−
+
−#ifdef  NU_ENABLE_STACK_CHECK
+
−
+
−    /* Call stack checking function to check for an overflow condition.  */
+
−    TCT_Check_Stack();
+
−
+
−#endif
+
−
+
−#ifdef  NU_ENABLE_HISTORY
+
−
+
−    /* Make an entry that corresponds to this function in the system history
+
−       log.  */
+
−    HIC_Make_History_Entry(NU_DEALLOCATE_MEMORY_ID, (UNSIGNED) memory,
+
−                                        (UNSIGNED) 0, (UNSIGNED) 0);
+
−
+
−#endif
+
−
+
−    /* Initialize the status as successful.  */
+
−    status =  NU_SUCCESS;
+
−
+
−    /* Pickup the associated pool's pointer.  It is inside the header of
+
−       each memory.  */
+
−    header_ptr =  (DM_HEADER *) (((BYTE_PTR) memory) - DM_OVERHEAD);
+
−    pool =        header_ptr -> dm_memory_pool;
+
−
+
−    /* Protect against simultaneous access to the memory pool.  */
+
−    TCT_Protect(&(pool -> dm_protect));
+
−
+
−    /* Mark the memory as available.  */
+
−    header_ptr -> dm_memory_free =  NU_TRUE;
+
−
+
−    /* Adjust the available number of bytes.  */
+
−    pool -> dm_available =  pool -> dm_available +
+
−                        (((BYTE_PTR) (header_ptr -> dm_next_memory)) -
+
−                           ((BYTE_PTR) header_ptr)) - DM_OVERHEAD;
+
−
+
−    /* Determine if the block can be merged with the previous neighbor.  */
+
−    if ((header_ptr -> dm_previous_memory) -> dm_memory_free)
+
−    {
+
−
+
−        /* Adjust the available number of bytes.  */
+
−        pool -> dm_available =  pool -> dm_available + DM_OVERHEAD;
+
−
+
−        /* Yes, merge block with previous neighbor.  */
+
−        (header_ptr -> dm_previous_memory) -> dm_next_memory =
+
−                                header_ptr -> dm_next_memory;
+
−        (header_ptr -> dm_next_memory) -> dm_previous_memory =
+
−                                header_ptr -> dm_previous_memory;
+
−
+
−        /* Move header pointer to previous.  */
+
−        header_ptr =  header_ptr -> dm_previous_memory;
+
−
+
−        /* Adjust the search pointer to the new merged block.  */
+
−        pool -> dm_search_ptr =  header_ptr;
+
−    }
+
−
+
−    /* Determine if the block can be merged with the next neighbor.  */
+
−    if ((header_ptr -> dm_next_memory) -> dm_memory_free)
+
−    {
+
−
+
−        /* Adjust the available number of bytes.  */
+
−        pool -> dm_available =  pool -> dm_available + DM_OVERHEAD;
+
−
+
−        /* Yes, merge block with next neighbor.  */
+
−        new_ptr =  header_ptr -> dm_next_memory;
+
−        (new_ptr -> dm_next_memory) -> dm_previous_memory =
+
−                                                header_ptr;
+
−        header_ptr -> dm_next_memory = new_ptr -> dm_next_memory;
+
−
+
−        /* Adjust the search pointer to the new merged block.  */
+
−        pool -> dm_search_ptr =  header_ptr;
+
−    }
+
−
+
−#ifdef INCLUDE_PROVIEW
+
−    _RTProf_DumpMemoryPool(RT_PROF_DEALLOCATE_MEMORY,pool,RT_PROF_OK);
+
−#endif /*INCLUDE_PROVIEW*/
+
−    /* Determine if another task is waiting for memory from the pool.  */
+
−    suspend_ptr =  pool -> dm_suspension_list;
+
−    preempt =      0;
+
−    while (suspend_ptr)
+
−    {
+
−
+
−        /* Yes, another task is waiting for memory from the pool.  Search
+
−           the pool in the same manner as the memory allocation function.  */
+
−        size =        suspend_ptr -> dm_request_size;
+
−        header_ptr =  pool -> dm_search_ptr;
+
−        do
+
−        {
+
−
+
−            /* Determine if the block is free and if it can satisfy the request
+
−               of the first task waiting. */
+
−            if (header_ptr -> dm_memory_free)
+
−
+
−                /* Calculate the free block size.  */
+
−                free_size =  (((BYTE_PTR) (header_ptr -> dm_next_memory)) -
+
−                               ((BYTE_PTR) header_ptr)) - DM_OVERHEAD;
+
−            else
+
−
+
−                /* There are no free bytes available.  */
+
−                free_size =  0;
+
−
+
−            /* Determine if the search should continue.  */
+
−            if (free_size < size)
+
−
+
−                /* Large enough block has not been found.  Move the search
+
−                   pointer to the next block.  */
+
−                header_ptr =  header_ptr -> dm_next_memory;
+
−        } while((free_size < size) && (header_ptr != pool -> dm_search_ptr));
+
−
+
−        /* Determine if the memory is available.  */
+
−        if (free_size >= size)
+
−        {
+
−
+
−            /* A block that satisfies the request has been found.  */
+
−
+
−            /* Determine if the block needs to be split.  */
+
−            if (free_size >= (size + DM_OVERHEAD + pool -> dm_min_allocation))
+
−            {
+
−
+
−                /* Yes, split the block.  */
+
−                new_ptr =  (DM_HEADER *) (((BYTE_PTR) header_ptr) + size +
+
−                                                                  DM_OVERHEAD);
+
−
+
−                /* Mark the new block as free.  */
+
−                new_ptr -> dm_memory_free =  NU_TRUE;
+
−
+
−                /* Put the pool pointer into the new block.  */
+
−                new_ptr -> dm_memory_pool =  pool;
+
−
+
−                /* Build the necessary pointers.  */
+
−                new_ptr -> dm_previous_memory =  header_ptr;
+
−                new_ptr -> dm_next_memory =      header_ptr -> dm_next_memory;
+
−                (new_ptr -> dm_next_memory) -> dm_previous_memory =  new_ptr;
+
−                header_ptr -> dm_next_memory =   new_ptr;
+
−
+
−                /* Decrement the available byte count.  */
+
−                pool -> dm_available =  pool -> dm_available -
+
−                                                        size - DM_OVERHEAD;
+
−            }
+
−            else
+
−
+
−                /* Decrement the entire free size from the available bytes
+
−                   count.  */
+
−                pool -> dm_available =  pool -> dm_available - free_size;
+
−
+
−            /* Mark the allocated block as not available.  */
+
−            header_ptr -> dm_memory_free =  NU_FALSE;
+
−
+
−            /* Should the search pointer be moved?   */
+
−            if (pool -> dm_search_ptr == header_ptr)
+
−
+
−                /* Move the search pointer to the next free memory slot.  */
+
−                pool -> dm_search_ptr =  header_ptr -> dm_next_memory;
+
−
+
−            /* Decrement the number of tasks waiting counter.  */
+
−            pool -> dm_tasks_waiting--;
+
−
+
−            /* Remove the first suspended block from the list.  */
+
−            CSC_Remove_From_List((CS_NODE **) &(pool -> dm_suspension_list),
+
−                                        &(suspend_ptr -> dm_suspend_link));
+
−
+
−            /* Setup the appropriate return value.  */
+
−            suspend_ptr -> dm_return_status =   NU_SUCCESS;
+
−            suspend_ptr -> dm_return_pointer =  (VOID *)
+
−                                (((BYTE_PTR) header_ptr) + DM_OVERHEAD);
+
−
+
−            /* Setup system protect while task is being resumed.  */
+
−            TCT_System_Protect();
+
−
+
−            /* Resume the suspended task.  */
+
−            preempt =  preempt |
+
−              TCC_Resume_Task((NU_TASK *) suspend_ptr -> dm_suspended_task,
+
−                                                        NU_MEMORY_SUSPEND);
+
−
+
−            /* Switch back to the pool protection.  */
+
−            TCT_Set_Current_Protect(&(pool -> dm_protect));
+
−
+
−            /* Release system protection.  */
+
−            TCT_System_Unprotect();
+
−
+
−            /* Pickup the next suspension pointer.  */
+
−            suspend_ptr =  pool -> dm_suspension_list;
+
−        }
+
−        else
+
−
+
−            /* Not enough memory for suspended task. */
+
−            suspend_ptr =  NU_NULL;
+
−    }
+
−
+
−    /* Determine if a preempt condition is present.  */
+
−    if (preempt)
+
−
+
−        /* Transfer control to the system if the resumed task function
+
−           detects a preemption condition.  */
+
−        TCT_Control_To_System();
+
−
+
−    /* Release protection of the memory pool.  */
+
−    TCT_Unprotect();
+
−
+
−    /* Return to user mode */
+
−    NU_USER_MODE();
+
−
+
−    /* Return the completion status.  */
+
−    return(status);
+
−}
+
−
+
−
+
−/*************************************************************************/
+
−/*                                                                       */
+
−/* FUNCTION                                                              */
+
−/*                                                                       */
+
−/*      DMC_Cleanup                                                      */
+
−/*                                                                       */
+
−/* DESCRIPTION                                                           */
+
−/*                                                                       */
+
−/*      This function is responsible for removing a suspension block     */
+
−/*      from a memory pool.  It is not called unless a timeout or        */
+
−/*      a task terminate is in progress.  Note that protection is        */
+
−/*      already in effect - the same protection at suspension time.      */
+
−/*                                                                       */
+
−/* CALLED BY                                                             */
+
−/*                                                                       */
+
−/*      TCC_Timeout                         Task timeout                 */
+
−/*      TCC_Terminate                       Task terminate               */
+
−/*                                                                       */
+
−/* CALLS                                                                 */
+
−/*                                                                       */
+
−/*      CSC_Remove_From_List                Remove suspend block from    */
+
−/*                                            the suspension list        */
+
−/*                                                                       */
+
−/* INPUTS                                                                */
+
−/*                                                                       */
+
−/*      information                         Pointer to suspend block     */
+
−/*                                                                       */
+
−/* OUTPUTS                                                               */
+
−/*                                                                       */
+
−/*      None                                                             */
+
−/*                                                                       */
+
−/* HISTORY                                                               */
+
−/*                                                                       */
+
−/*         DATE                    REMARKS                               */
+
−/*                                                                       */
+
−/*      03-01-1993      Created initial version 1.0                      */
+
−/*      04-19-1993      Verified version 1.0                             */
+
−/*                                                                       */
+
−/*************************************************************************/
+
−VOID  DMC_Cleanup(VOID *information)
+
−{
+
−
+
−DM_SUSPEND      *suspend_ptr;               /* Suspension block pointer  */
+
−NU_SUPERV_USER_VARIABLES
+
−
+
−    /* Switch to supervisor mode */
+
−    NU_SUPERVISOR_MODE();
+
−
+
−    /* Use the information pointer as a suspend pointer.  */
+
−    suspend_ptr =  (DM_SUSPEND *) information;
+
−
+
−    /* By default, indicate that the service timed-out.  It really does not
+
−       matter if this function is called from a terminate request since
+
−       the task does not resume.  */
+
−    suspend_ptr -> dm_return_status =   NU_TIMEOUT;
+
−    suspend_ptr -> dm_return_pointer =  NU_NULL;
+
−
+
−    /* Decrement the number of tasks waiting counter.  */
+
−    (suspend_ptr -> dm_memory_pool) -> dm_tasks_waiting--;
+
−
+
−    /* Unlink the suspend block from the suspension list.  */
+
−    CSC_Remove_From_List((CS_NODE **)
+
−                &((suspend_ptr -> dm_memory_pool) -> dm_suspension_list),
+
−                                &(suspend_ptr -> dm_suspend_link));
+
−
+
−    /* Return to user mode */
+
−    NU_USER_MODE();
+
−}
+
−
+
−
+
−
+
−
+
−
+
−
+
−