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/**************************************************************************/
/* */
/* 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 */
/** */
/** Semaphore */
/** */
/**************************************************************************/
/**************************************************************************/
#define TX_SOURCE_CODE
/* Include necessary system files. */
#include "tx_api.h"
#include "tx_trace.h"
#include "tx_thread.h"
#include "tx_semaphore.h"
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _tx_semaphore_ceiling_put PORTABLE C */
/* 6.1 */
/* AUTHOR */
/* */
/* William E. Lamie, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function puts an instance into the specified counting */
/* semaphore up to the specified semaphore ceiling. */
/* */
/* INPUT */
/* */
/* semaphore_ptr Pointer to semaphore */
/* ceiling Maximum value of semaphore */
/* */
/* OUTPUT */
/* */
/* status Completion status */
/* */
/* CALLS */
/* */
/* _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_semaphore_ceiling_put(TX_SEMAPHORE *semaphore_ptr, ULONG ceiling)
{
TX_INTERRUPT_SAVE_AREA
#ifndef TX_DISABLE_NOTIFY_CALLBACKS
VOID (*semaphore_put_notify)(struct TX_SEMAPHORE_STRUCT *notify_semaphore_ptr);
#endif
TX_THREAD *thread_ptr;
UINT suspended_count;
TX_THREAD *next_thread;
TX_THREAD *previous_thread;
UINT status;
/* Default the status to TX_SUCCESS. */
status = TX_SUCCESS;
/* Disable interrupts to put an instance back to the semaphore. */
TX_DISABLE
#ifdef TX_SEMAPHORE_ENABLE_PERFORMANCE_INFO
/* Increment the total semaphore put counter. */
_tx_semaphore_performance_put_count++;
/* Increment the number of puts on this semaphore. */
semaphore_ptr -> tx_semaphore_performance_put_count++;
#endif
/* If trace is enabled, insert this event into the trace buffer. */
TX_TRACE_IN_LINE_INSERT(TX_TRACE_SEMAPHORE_CEILING_PUT, semaphore_ptr, semaphore_ptr -> tx_semaphore_count, semaphore_ptr -> tx_semaphore_suspended_count, ceiling, TX_TRACE_SEMAPHORE_EVENTS)
/* Log this kernel call. */
TX_EL_SEMAPHORE_CEILING_PUT_INSERT
/* Pickup the number of suspended threads. */
suspended_count = semaphore_ptr -> tx_semaphore_suspended_count;
/* Determine if there are any threads suspended on the semaphore. */
if (suspended_count == TX_NO_SUSPENSIONS)
{
/* Determine if the ceiling has been exceeded. */
if (semaphore_ptr -> tx_semaphore_count >= ceiling)
{
/* Restore interrupts. */
TX_RESTORE
/* Return an error. */
status = TX_CEILING_EXCEEDED;
}
else
{
/* Increment the semaphore count. */
semaphore_ptr -> tx_semaphore_count++;
#ifndef TX_DISABLE_NOTIFY_CALLBACKS
/* Pickup the application notify function. */
semaphore_put_notify = semaphore_ptr -> tx_semaphore_put_notify;
#endif
/* Restore interrupts. */
TX_RESTORE
#ifndef TX_DISABLE_NOTIFY_CALLBACKS
/* Determine if notification is required. */
if (semaphore_put_notify != TX_NULL)
{
/* Yes, call the appropriate notify callback function. */
(semaphore_put_notify)(semaphore_ptr);
}
#endif
/* Return successful completion status. */
status = TX_SUCCESS;
}
}
else
{
/* Remove the suspended thread from the list. */
/* Pickup the pointer to the first suspended thread. */
thread_ptr = semaphore_ptr -> tx_semaphore_suspension_list;
/* See if this is the only suspended thread on the list. */
suspended_count--;
if (suspended_count == TX_NO_SUSPENSIONS)
{
/* Yes, the only suspended thread. */
/* Update the head pointer. */
semaphore_ptr -> tx_semaphore_suspension_list = TX_NULL;
}
else
{
/* At least one more thread is on the same expiration list. */
/* Update the list head pointer. */
next_thread = thread_ptr -> tx_thread_suspended_next;
semaphore_ptr -> tx_semaphore_suspension_list = next_thread;
/* Update the links of the adjacent threads. */
previous_thread = thread_ptr -> tx_thread_suspended_previous;
next_thread -> tx_thread_suspended_previous = previous_thread;
previous_thread -> tx_thread_suspended_next = next_thread;
}
/* Decrement the suspension count. */
semaphore_ptr -> tx_semaphore_suspended_count = suspended_count;
/* Prepare for resumption of the first thread. */
/* Clear cleanup routine to avoid timeout. */
thread_ptr -> tx_thread_suspend_cleanup = TX_NULL;
/* Put return status into the thread control block. */
thread_ptr -> tx_thread_suspend_status = TX_SUCCESS;
#ifndef TX_DISABLE_NOTIFY_CALLBACKS
/* Pickup the application notify function. */
semaphore_put_notify = semaphore_ptr -> tx_semaphore_put_notify;
#endif
#ifdef TX_NOT_INTERRUPTABLE
/* Resume the thread! */
_tx_thread_system_ni_resume(thread_ptr);
/* Restore interrupts. */
TX_RESTORE
#else
/* Temporarily disable preemption. */
_tx_thread_preempt_disable++;
/* Restore interrupts. */
TX_RESTORE
/* Resume thread. */
_tx_thread_system_resume(thread_ptr);
#endif
#ifndef TX_DISABLE_NOTIFY_CALLBACKS
/* Determine if notification is required. */
if (semaphore_put_notify != TX_NULL)
{
/* Yes, call the appropriate notify callback function. */
(semaphore_put_notify)(semaphore_ptr);
}
#endif
}
/* Return successful completion. */
return(status);
}