📄 tx_ba.c
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/**************************************************************************/
/* */
/* Copyright (c) 1996-2000 by Express Logic Inc. */
/* */
/* This software is copyrighted by and is the sole property of Express */
/* Logic, Inc. All rights, title, ownership, or other interests */
/* in the software remain the property of Express Logic, Inc. This */
/* software may only be used in accordance with the corresponding */
/* license agreement. Any unauthorized use, duplication, transmission, */
/* distribution, or disclosure of this software is expressly forbidden. */
/* */
/* This Copyright notice may not be removed or modified without prior */
/* written consent of Express Logic, Inc. */
/* */
/* Express Logic, Inc. reserves the right to modify this software */
/* without notice. */
/* */
/* Express Logic, Inc. */
/* 11440 West Bernardo Court info@expresslogic.com */
/* Suite 366 http://www.expresslogic.com */
/* San Diego, CA 92127 */
/* */
/**************************************************************************/
/**************************************************************************/
/**************************************************************************/
/** */
/** ThreadX Component */
/** */
/** Block Pool (BLO) */
/** */
/**************************************************************************/
/**************************************************************************/
#define TX_SOURCE_CODE
/* Include necessary system files. */
#include "tx_api.h"
#include "tx_thr.h"
#include "tx_tim.h"
#include "tx_blo.h"
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _tx_block_allocate PORTABLE C */
/* 3.0f */
/* AUTHOR */
/* */
/* William E. Lamie, Express Logic, Inc. */
/* */
/* DESCRIPTION */
/* */
/* This function allocates a block from the specified memory block */
/* pool. */
/* */
/* INPUT */
/* */
/* pool_ptr Pointer to pool control block */
/* block_ptr Pointer to place allocated block */
/* pointer */
/* wait_option Suspension option */
/* */
/* OUTPUT */
/* */
/* status Completion status */
/* */
/* CALLS */
/* */
/* _tx_timer_activate Activate timer routine */
/* _tx_thread_suspend Suspend thread service */
/* */
/* CALLED BY */
/* */
/* Application Code */
/* */
/* RELEASE HISTORY */
/* */
/* DATE NAME DESCRIPTION */
/* */
/* 12-31-1996 William E. Lamie Initial Version 3.0 */
/* 11-11-1997 William E. Lamie Modified comment(s), */
/* resulting in version 3.0b. */
/* 03-01-1998 William E. Lamie Optimized post RESTORE */
/* processing, resulting in */
/* version 3.0d. */
/* 01-01-1999 William E. Lamie Modified comment(s), */
/* resulting in version 3.0e. */
/* 11-01-1999 William E. Lamie Modified comment(s), */
/* added logic to track events,*/
/* resulting in version 3.0f. */
/* */
/**************************************************************************/
UINT _tx_block_allocate(TX_BLOCK_POOL *pool_ptr, VOID **block_ptr, ULONG wait_option)
{
TX_INTERRUPT_SAVE_AREA
REG_1 UINT status; /* Return status */
REG_2 TX_THREAD *thread_ptr; /* Working thread pointer */
REG_3 CHAR_PTR work_ptr; /* Working block pointer */
/* Disable interrupts to get a block from the pool. */
TX_DISABLE
/* Log this kernel call. */
TX_EL_BLOCK_ALLOCATE_INSERT
/* Determine if there is an available block. */
if (pool_ptr -> tx_block_pool_available)
{
/* Yes, a block is available. Decrement the available count. */
pool_ptr -> tx_block_pool_available--;
/* Pickup the current block pointer. */
work_ptr = pool_ptr -> tx_block_pool_available_list;
/* Return the first available block to the caller. */
*((CHAR_PTR *) block_ptr) = work_ptr + sizeof(CHAR_PTR);
/* Modify the available list to point at the next block in the pool. */
pool_ptr -> tx_block_pool_available_list =
*((CHAR_PTR *) work_ptr);
/* Save the pool's address in the block for when it is released! */
*((CHAR_PTR *) work_ptr) = (CHAR_PTR) pool_ptr;
/* Set status to success. */
status = TX_SUCCESS;
}
else
{
/* Determine if the request specifies suspension. */
if (wait_option)
{
/* Prepare for suspension of this thread. */
/* Pickup thread pointer. */
thread_ptr = _tx_thread_current_ptr;
/* Setup cleanup routine pointer. */
thread_ptr -> tx_suspend_cleanup = _tx_block_pool_cleanup;
/* Setup cleanup information, i.e. this pool control
block. */
thread_ptr -> tx_suspend_control_block = (VOID_PTR) pool_ptr;
/* Save the return block pointer address as well. */
thread_ptr -> tx_additional_suspend_info = (VOID_PTR) block_ptr;
/* Setup suspension list. */
if (pool_ptr -> tx_block_pool_suspension_list)
{
/* This list is not NULL, add current thread to the end. */
thread_ptr -> tx_suspended_next =
pool_ptr -> tx_block_pool_suspension_list;
thread_ptr -> tx_suspended_previous =
(pool_ptr -> tx_block_pool_suspension_list) -> tx_suspended_previous;
((pool_ptr -> tx_block_pool_suspension_list) -> tx_suspended_previous) -> tx_suspended_next =
thread_ptr;
(pool_ptr -> tx_block_pool_suspension_list) -> tx_suspended_previous = thread_ptr;
}
else
{
/* No other threads are suspended. Setup the head pointer and
just setup this threads pointers to itself. */
pool_ptr -> tx_block_pool_suspension_list = thread_ptr;
thread_ptr -> tx_suspended_next = thread_ptr;
thread_ptr -> tx_suspended_previous = thread_ptr;
}
/* Increment the suspended thread count. */
pool_ptr -> tx_block_pool_suspended_count++;
/* Set the state to suspended. */
thread_ptr -> tx_state = TX_BLOCK_MEMORY;
/* Set the suspending flag. */
thread_ptr -> tx_suspending = TX_TRUE;
/* Temporarily disable preemption. */
_tx_thread_preempt_disable++;
/* Save the timeout value. */
thread_ptr -> tx_thread_timer.tx_remaining_ticks = wait_option;
/* Restore interrupts. */
TX_RESTORE
/* See if we need to start a timer. */
if (wait_option != TX_WAIT_FOREVER)
{
/* A timeout is required. */
/* Activate the thread timer for the timeout. */
_tx_timer_activate(&(thread_ptr -> tx_thread_timer));
}
/* Call actual thread suspension routine. */
_tx_thread_suspend(thread_ptr);
/* Return the completion status. */
return(thread_ptr -> tx_suspend_status);
}
else
/* Immediate return, return error completion. */
status = TX_NO_MEMORY;
}
/* Restore interrupts. */
TX_RESTORE
/* Return completion status. */
return(status);
}
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