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|
/***************************************************************************
* Copyright (c) 2024 Microsoft Corporation
* Copyright (c) 2026-present Eclipse ThreadX contributors
*
* This program and the accompanying materials are made available under the
* terms of the MIT License which is available at
* https://opensource.org/licenses/MIT.
*
* SPDX-License-Identifier: MIT
**************************************************************************/
/**************************************************************************/
/**************************************************************************/
/** */
/** ThreadX Component */
/** */
/** Thread */
/** */
/**************************************************************************/
/**************************************************************************/
#define TX_SOURCE_CODE
#define TX_THREAD_SMP_SOURCE_CODE
/* Include necessary system files. */
#include "tx_api.h"
#include "tx_thread.h"
#include "tx_timer.h"
#include <stdio.h>
#include <errno.h>
extern sem_t _tx_linux_isr_semaphore;
extern UINT _tx_linux_timer_waiting;
extern pthread_t _tx_linux_timer_id;
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _tx_thread_schedule SMP/Linux/GCC */
/* 6.1 */
/* AUTHOR */
/* */
/* William E. Lamie, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function waits for a thread control block pointer to appear in */
/* the _tx_thread_execute_ptr variable. Once a thread pointer appears */
/* in the variable, the corresponding thread is resumed. */
/* */
/* INPUT */
/* */
/* None */
/* */
/* OUTPUT */
/* */
/* None */
/* */
/* CALLS */
/* */
/* _tx_linux_mutex_obtain */
/* _tx_linux_debug_entry_insert */
/* _tx_linux_thread_resume */
/* tx_linux_sem_post */
/* sem_trywait */
/* tx_linux_sem_wait */
/* */
/* CALLED BY */
/* */
/* _tx_initialize_kernel_enter ThreadX entry function */
/* */
/**************************************************************************/
VOID _tx_thread_schedule(VOID)
{
UINT core;
TX_THREAD *current_thread;
TX_THREAD *execute_thread;
struct timespec ts;
UCHAR preemt_retry = TX_FALSE;
/* Loop forever. */
while(1)
{
/* Lock Linux mutex. */
_tx_linux_mutex_obtain(&_tx_linux_mutex);
/* Check for a system error condition. */
if (_tx_linux_global_int_disabled_flag != TX_FALSE)
{
/* This should not happen... increment the system error counter. */
_tx_linux_system_error++;
}
/* Debug entry. */
_tx_linux_debug_entry_insert("SCHEDULE-wake_up", __FILE__, __LINE__);
/* Loop through each virtual core to look for an idle core. */
for (core = 0; core < TX_THREAD_SMP_MAX_CORES; core++)
{
/* Pickup the current thread pointer for this core. */
current_thread = _tx_thread_current_ptr[core];
/* Determine if the thread's deferred preemption flag is set. */
if ((current_thread) && (current_thread -> tx_thread_linux_deferred_preempt))
{
if (_tx_thread_preempt_disable)
{
/* Preemption disabled. Retry. */
preemt_retry = TX_TRUE;
break;
}
if (current_thread -> tx_thread_state != TX_TERMINATED)
{
/* Suspend the thread to simulate preemption. Note that the thread is suspended BEFORE the protection get
flag is checked to ensure there is not a race condition between this thread and the update of that flag. */
_tx_linux_thread_suspend(current_thread -> tx_thread_linux_thread_id);
/* Clear the preemption flag. */
current_thread -> tx_thread_linux_deferred_preempt = TX_FALSE;
/* Indicate that this thread was suspended asynchronously. */
current_thread -> tx_thread_linux_suspension_type = 1;
/* Save the remaining time-slice and disable it. */
if (_tx_timer_time_slice[core])
{
current_thread -> tx_thread_time_slice = _tx_timer_time_slice[core];
_tx_timer_time_slice[core] = 0;
}
}
/* Clear the current thread pointer. */
_tx_thread_current_ptr[core] = TX_NULL;
/* Clear this mapping entry. */
_tx_linux_virtual_cores[core].tx_thread_smp_core_mapping_thread = TX_NULL;
_tx_linux_virtual_cores[core].tx_thread_smp_core_mapping_linux_thread_id = 0;
/* Indicate that this thread is now ready for scheduling again by another core. */
current_thread -> tx_thread_smp_core_control = 1;
/* Debug entry. */
_tx_linux_debug_entry_insert("SCHEDULE-core_preempt_complete", __FILE__, __LINE__);
}
/* Determine if this core is idle. */
if (_tx_thread_current_ptr[core] == TX_NULL)
{
/* Yes, this core is idle, determine if there is a thread that can be scheduled for it. */
/* Pickup the execute thread pointer. */
execute_thread = _tx_thread_execute_ptr[core];
/* Is there a thread that is ready to execute on this core? */
if ((execute_thread) && (execute_thread -> tx_thread_smp_core_control))
{
/* Yes! We have a thread to execute. Note that the critical section is already
active from the scheduling loop above. */
/* Setup the current thread pointer. */
_tx_thread_current_ptr[core] = execute_thread;
/* Remember the virtual core in the thread control block. */
execute_thread -> tx_thread_linux_virtual_core = core;
/* Setup the virtual core mapping structure. */
_tx_linux_virtual_cores[core].tx_thread_smp_core_mapping_thread = execute_thread;
_tx_linux_virtual_cores[core].tx_thread_smp_core_mapping_linux_thread_id = execute_thread -> tx_thread_linux_thread_id;
/* Clear the execution control flag. */
execute_thread -> tx_thread_smp_core_control = 0;
/* Increment the run count for this thread. */
execute_thread -> tx_thread_run_count++;
/* Setup time-slice, if present. */
_tx_timer_time_slice[core] = execute_thread -> tx_thread_time_slice;
/* Determine how the thread was last suspended. */
if (execute_thread -> tx_thread_linux_suspension_type == 1)
{
/* Clear the suspension type. */
execute_thread -> tx_thread_linux_suspension_type = 0;
/* Debug entry. */
_tx_linux_debug_entry_insert("SCHEDULE-resume_thread", __FILE__, __LINE__);
/* Pseudo interrupt suspension. The thread is not waiting on
its run semaphore. */
_tx_linux_thread_resume(execute_thread -> tx_thread_linux_thread_id);
}
else if (execute_thread -> tx_thread_linux_suspension_type == 2)
{
/* Clear the suspension type. */
execute_thread -> tx_thread_linux_suspension_type = 0;
/* Debug entry. */
_tx_linux_debug_entry_insert("SCHEDULE-release_sem", __FILE__, __LINE__);
/* Make sure semaphore is 0. */
while(!sem_trywait(&execute_thread -> tx_thread_linux_thread_run_semaphore));
/* Let the thread run again by releasing its run semaphore. */
tx_linux_sem_post(&execute_thread -> tx_thread_linux_thread_run_semaphore);
/* Block timer ISR. */
if(_tx_linux_timer_waiting)
{
/* It is woken up by timer ISR. */
/* Let ThreadX thread wake up first. */
tx_linux_sem_wait(&_tx_linux_scheduler_semaphore);
/* Wake up timer ISR. */
tx_linux_sem_post(&_tx_linux_isr_semaphore);
}
else
{
/* It is woken up by TX_THREAD. */
/* Suspend timer thread and let ThreadX thread wake up first. */
_tx_linux_thread_suspend(_tx_linux_timer_id);
tx_linux_sem_wait(&_tx_linux_scheduler_semaphore);
_tx_linux_thread_resume(_tx_linux_timer_id);
}
}
else
{
/* System error, increment the counter. */
_tx_linux_system_error++;
}
}
}
}
if (preemt_retry)
{
/* Unlock linux mutex. */
_tx_linux_mutex_release_all(&_tx_linux_mutex);
/* Let user thread run to reset _tx_thread_preempt_disable. */
_tx_linux_thread_sleep(1);
preemt_retry = TX_FALSE;
continue;
}
/* Debug entry. */
_tx_linux_debug_entry_insert("SCHEDULE-self_suspend_sem", __FILE__, __LINE__);
/* Unlock linux mutex. */
_tx_linux_mutex_release_all(&_tx_linux_mutex);
/* Now suspend the main thread so the application thread can run. */
clock_gettime(CLOCK_REALTIME, &ts);
ts.tv_nsec += 2000000;
if (ts.tv_nsec >= 1000000000)
{
ts.tv_nsec -= 1000000000;
ts.tv_sec++;
}
tx_linux_sem_timedwait(&_tx_linux_scheduler_semaphore, &ts);
clock_gettime(CLOCK_REALTIME, &ts);
}
}
/* Define the ThreadX Linux mutex get, release, and release all functions. */
void _tx_linux_mutex_obtain(TX_LINUX_MUTEX *mutex)
{
TX_THREAD *thread_ptr;
pthread_t current_thread_id;
UINT i;
/* Pickup the current thread ID. */
current_thread_id = pthread_self();
/* Is the protection owned? */
if (mutex -> tx_linux_mutex_owner == current_thread_id)
{
/* Simply increment the nested counter. */
mutex -> tx_linux_mutex_nested_count++;
}
else
{
/* Loop to find a thread matching this ID. */
i = 0;
do
{
/* Pickup the thread pointer. */
thread_ptr = _tx_thread_current_ptr[i];
/* Is this thread obtaining the mutex? */
if ((thread_ptr) && (thread_ptr -> tx_thread_linux_thread_id == current_thread_id))
{
/* We have found the thread, get out of the loop. */
break;
}
/* Look at next core. */
i++;
} while (i < TX_THREAD_SMP_MAX_CORES);
/* Determine if we found a thread. */
if (i >= TX_THREAD_SMP_MAX_CORES)
{
/* Set the thread pointer to NULL to indicate a thread was not found. */
thread_ptr = TX_NULL;
}
/* If a thread was found, indicate the thread is attempting to access the mutex. */
if (thread_ptr)
{
/* Yes, current ThreadX thread attempting to get the mutex - set the flag. */
thread_ptr -> tx_thread_linux_mutex_access = TX_TRUE;
}
/* Get the Linux mutex. */
pthread_mutex_lock(&mutex -> tx_linux_mutex);
/* At this point we have the mutex. */
/* Clear the mutex access flag for the thread. */
if (thread_ptr)
{
/* Yes, clear the current ThreadX thread attempting to get the mutex. */
thread_ptr -> tx_thread_linux_mutex_access = TX_FALSE;
}
/* Increment the nesting counter. */
mutex -> tx_linux_mutex_nested_count = 1;
/* Remember the owner. */
mutex -> tx_linux_mutex_owner = pthread_self();
}
}
void _tx_linux_mutex_release(TX_LINUX_MUTEX *mutex)
{
pthread_t current_thread_id;
/* Pickup the current thread ID. */
current_thread_id = pthread_self();
/* Ensure the caller is the mutex owner. */
if (mutex -> tx_linux_mutex_owner == current_thread_id)
{
/* Determine if there is protection. */
if (mutex -> tx_linux_mutex_nested_count)
{
/* Decrement the nesting counter. */
mutex -> tx_linux_mutex_nested_count--;
/* Determine if the critical section is now being released. */
if (mutex -> tx_linux_mutex_nested_count == 0)
{
/* Yes, it is being released clear the owner. */
mutex -> tx_linux_mutex_owner = 0;
/* Finally, release the mutex. */
if (pthread_mutex_unlock(&mutex -> tx_linux_mutex) != 0)
{
/* Increment the system error counter. */
_tx_linux_system_error++;
}
/* Just in case, make sure there the mutex is not owned. */
while (pthread_mutex_unlock(&mutex -> tx_linux_mutex) == 0)
{
/* Increment the system error counter. */
_tx_linux_system_error++;
}
/* Relinquish to other ready threads. */
_tx_linux_thread_sleep(1000);
}
}
}
else
{
/* Increment the system error counter. */
_tx_linux_system_error++;
}
}
void _tx_linux_mutex_release_all(TX_LINUX_MUTEX *mutex)
{
/* Ensure the caller is the mutex owner. */
if (mutex -> tx_linux_mutex_owner == pthread_self())
{
/* Determine if there is protection. */
if (mutex -> tx_linux_mutex_nested_count)
{
/* Clear the nesting counter. */
mutex -> tx_linux_mutex_nested_count = 0;
/* Yes, it is being release clear the owner. */
mutex -> tx_linux_mutex_owner = 0;
/* Finally, release the mutex. */
if (pthread_mutex_unlock(&mutex -> tx_linux_mutex) != 0)
{
/* Increment the system error counter. */
_tx_linux_system_error++;
}
/* Just in case, make sure there the mutex is not owned. */
while (pthread_mutex_unlock(&mutex -> tx_linux_mutex) == 0)
{
/* Increment the system error counter. */
_tx_linux_system_error++;
}
}
}
else
{
/* Increment the system error counter. */
_tx_linux_system_error++;
}
}
void _tx_thread_delete_port_completion(TX_THREAD *thread_ptr, UINT tx_interrupt_save)
{
INT linux_status;
sem_t *threadrunsemaphore;
pthread_t thread_id;
thread_id = thread_ptr -> tx_thread_linux_thread_id;
threadrunsemaphore = &(thread_ptr -> tx_thread_linux_thread_run_semaphore);
_tx_thread_smp_unprotect(tx_interrupt_save);
do
{
linux_status = pthread_cancel(thread_id);
if(linux_status != EAGAIN)
{
break;
}
_tx_linux_thread_resume(thread_id);
tx_linux_sem_post(threadrunsemaphore);
_tx_linux_thread_sleep(1000000);
} while (1);
pthread_join(thread_id, NULL);
sem_destroy(threadrunsemaphore);
tx_interrupt_save = _tx_thread_smp_protect();
}
void _tx_thread_reset_port_completion(TX_THREAD *thread_ptr, UINT tx_interrupt_save)
{
INT linux_status;
sem_t *threadrunsemaphore;
pthread_t thread_id;
thread_id = thread_ptr -> tx_thread_linux_thread_id;
threadrunsemaphore = &(thread_ptr -> tx_thread_linux_thread_run_semaphore);
_tx_thread_smp_unprotect(tx_interrupt_save);
do
{
linux_status = pthread_cancel(thread_id);
if(linux_status != EAGAIN)
{
break;
}
_tx_linux_thread_resume(thread_id);
tx_linux_sem_post(threadrunsemaphore);
_tx_linux_thread_sleep(1000000);
} while (1);
pthread_join(thread_id, NULL);
sem_destroy(threadrunsemaphore);
tx_interrupt_save = _tx_thread_smp_protect();
}
|
