stw24/Middlewares/ST/threadx/common/src/tx_queue_flush.c

208 lines
8.7 KiB
C

/**************************************************************************/
/* */
/* Copyright (c) Microsoft Corporation. All rights reserved. */
/* */
/* This software is licensed under the Microsoft Software License */
/* Terms for Microsoft Azure RTOS. Full text of the license can be */
/* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */
/* and in the root directory of this software. */
/* */
/**************************************************************************/
/**************************************************************************/
/**************************************************************************/
/** */
/** ThreadX Component */
/** */
/** Queue */
/** */
/**************************************************************************/
/**************************************************************************/
#define TX_SOURCE_CODE
/* Include necessary system files. */
#include "tx_api.h"
#include "tx_trace.h"
#include "tx_thread.h"
#include "tx_queue.h"
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _tx_queue_flush PORTABLE C */
/* 6.1 */
/* AUTHOR */
/* */
/* William E. Lamie, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function resets the specified queue, if there are any messages */
/* in it. Messages waiting to be placed on the queue are also thrown */
/* out. */
/* */
/* INPUT */
/* */
/* queue_ptr Pointer to queue control block */
/* */
/* OUTPUT */
/* */
/* TX_SUCCESS Successful completion status */
/* */
/* CALLS */
/* */
/* _tx_thread_system_preempt_check Check for preemption */
/* _tx_thread_system_resume Resume thread service */
/* _tx_thread_system_ni_resume Non-interruptable resume thread */
/* */
/* CALLED BY */
/* */
/* Application Code */
/* */
/* RELEASE HISTORY */
/* */
/* DATE NAME DESCRIPTION */
/* */
/* 05-19-2020 William E. Lamie Initial Version 6.0 */
/* 09-30-2020 Yuxin Zhou Modified comment(s), */
/* resulting in version 6.1 */
/* */
/**************************************************************************/
UINT _tx_queue_flush(TX_QUEUE *queue_ptr)
{
TX_INTERRUPT_SAVE_AREA
TX_THREAD *suspension_list;
UINT suspended_count;
TX_THREAD *thread_ptr;
/* Initialize the suspended count and list. */
suspended_count = TX_NO_SUSPENSIONS;
suspension_list = TX_NULL;
/* Disable interrupts to reset various queue parameters. */
TX_DISABLE
/* If trace is enabled, insert this event into the trace buffer. */
TX_TRACE_IN_LINE_INSERT(TX_TRACE_QUEUE_FLUSH, queue_ptr, TX_POINTER_TO_ULONG_CONVERT(&thread_ptr), 0, 0, TX_TRACE_QUEUE_EVENTS)
/* Log this kernel call. */
TX_EL_QUEUE_FLUSH_INSERT
/* Determine if there is something on the queue. */
if (queue_ptr -> tx_queue_enqueued != TX_NO_MESSAGES)
{
/* Yes, there is something in the queue. */
/* Reset the queue parameters to erase all of the queued messages. */
queue_ptr -> tx_queue_enqueued = TX_NO_MESSAGES;
queue_ptr -> tx_queue_available_storage = queue_ptr -> tx_queue_capacity;
queue_ptr -> tx_queue_read = queue_ptr -> tx_queue_start;
queue_ptr -> tx_queue_write = queue_ptr -> tx_queue_start;
/* Now determine if there are any threads suspended on a full queue. */
if (queue_ptr -> tx_queue_suspended_count != TX_NO_SUSPENSIONS)
{
/* Yes, there are threads suspended on this queue, they must be
resumed! */
/* Copy the information into temporary variables. */
suspension_list = queue_ptr -> tx_queue_suspension_list;
suspended_count = queue_ptr -> tx_queue_suspended_count;
/* Clear the queue variables. */
queue_ptr -> tx_queue_suspension_list = TX_NULL;
queue_ptr -> tx_queue_suspended_count = TX_NO_SUSPENSIONS;
/* Temporarily disable preemption. */
_tx_thread_preempt_disable++;
}
}
/* Restore interrupts. */
TX_RESTORE
/* Walk through the queue list to resume any and all threads suspended
on this queue. */
if (suspended_count != TX_NO_SUSPENSIONS)
{
/* Pickup the thread to resume. */
thread_ptr = suspension_list;
while (suspended_count != ((ULONG) 0))
{
/* Decrement the suspension count. */
suspended_count--;
/* Check for a NULL thread pointer. */
if (thread_ptr == TX_NULL)
{
/* Get out of the loop. */
break;
}
/* Resume the next suspended thread. */
/* Lockout interrupts. */
TX_DISABLE
/* Clear the cleanup pointer, this prevents the timeout from doing
anything. */
thread_ptr -> tx_thread_suspend_cleanup = TX_NULL;
/* Set the return status in the thread to TX_SUCCESS. */
thread_ptr -> tx_thread_suspend_status = TX_SUCCESS;
/* Move the thread pointer ahead. */
thread_ptr = thread_ptr -> tx_thread_suspended_next;
#ifdef TX_NOT_INTERRUPTABLE
/* Resume the thread! */
_tx_thread_system_ni_resume(thread_ptr -> tx_thread_suspended_previous);
/* Restore interrupts. */
TX_RESTORE
#else
/* Temporarily disable preemption again. */
_tx_thread_preempt_disable++;
/* Restore interrupts. */
TX_RESTORE
/* Resume the thread. */
_tx_thread_system_resume(thread_ptr -> tx_thread_suspended_previous);
#endif
}
/* Disable interrupts. */
TX_DISABLE
/* Restore previous preempt posture. */
_tx_thread_preempt_disable--;
/* Restore interrupts. */
TX_RESTORE
/* Check for preemption. */
_tx_thread_system_preempt_check();
}
/* Return TX_SUCCESS. */
return(TX_SUCCESS);
}