void dq_addbefore(FAR dq_entry_t *next, FAR dq_entry_t *node,
dq_queue_t *queue)
{
if (!queue->head || next == queue->head)
{
dq_addfirst(node, queue);
}
else
{
FAR dq_entry_t *prev = next->blink;
node->flink = next;
node->blink = prev;
prev->flink = node;
next->blink = node;
}
}
static int thread_schedsetup(FAR struct tcb_s *tcb, int priority,
start_t start, CODE void *entry, uint8_t ttype)
{
int ret;
/* Assign a unique task ID to the task. */
ret = task_assignpid(tcb);
if (ret == OK)
{
/* Save task priority and entry point in the TCB */
tcb->sched_priority = (uint8_t)priority;
#ifdef CONFIG_PRIORITY_INHERITANCE
tcb->base_priority = (uint8_t)priority;
#endif
tcb->start = start;
tcb->entry.main = (main_t)entry;
/* Save the thread type. This setting will be needed in
* up_initial_state() is called.
*/
ttype &= TCB_FLAG_TTYPE_MASK;
tcb->flags &= ~TCB_FLAG_TTYPE_MASK;
tcb->flags |= ttype;
/* Save the task ID of the parent task in the TCB and allocate
* a child status structure.
*/
task_saveparent(tcb, ttype);
/* exec(), pthread_create(), task_create(), and vfork() all
* inherit the signal mask of the parent thread.
*/
#ifndef CONFIG_DISABLE_SIGNALS
(void)sigprocmask(SIG_SETMASK, NULL, &tcb->sigprocmask);
#endif
/* Initialize the task state. It does not get a valid state
* until it is activated.
*/
tcb->task_state = TSTATE_TASK_INVALID;
/* Clone the parent tasks D-Space (if it was running PIC). This
* must be done before calling up_initial_state() so that the
* state setup will take the PIC address base into account.
*/
task_dupdspace(tcb);
/* Initialize the processor-specific portion of the TCB */
up_initial_state(tcb);
/* Add the task to the inactive task list */
sched_lock();
dq_addfirst((FAR dq_entry_t*)tcb, (dq_queue_t*)&g_inactivetasks);
tcb->task_state = TSTATE_TASK_INACTIVE;
sched_unlock();
}
return ret;
}
FAR sem_t *sem_open (FAR const char *name, int oflag, ...)
{
int namelen;
FAR nsem_t *psem;
FAR sem_t *sem = (FAR sem_t*)ERROR;
va_list arg; /* Points to each un-named argument */
unsigned int value; /* Semaphore value parameter */
/* Make sure that a non-NULL name is supplied */
if (name)
{
/* The POSIX specification requires that the "check for the
* existence of a semaphore and the creation of the semaphore
* if it does not exist shall be atomic with respect to other
* processes executing sem_open()..." A simple sched_lock()
* should be sufficient to meet this requirement.
*/
sched_lock();
namelen = strlen(name);
if (namelen > 0)
{
/* See if the semaphore already exists */
psem = sem_findnamed(name);
if (psem)
{
/* It does. Check if the caller wanted to created
* a new semahore with this name.
*/
if (!(oflag & O_CREAT) || !(oflag & O_EXCL))
{
/* Allow a new connection to the semaphore */
psem->nconnect++;
sem = &psem->sem;
}
}
/* It doesn't exist. Should we create one? */
else if ((oflag & O_CREAT) != 0)
{
/* Set up to get the optional arguments needed to create
* a message queue.
*/
va_start(arg, oflag);
(void)va_arg(arg, mode_t); /* Creation mode parameter (ignored) */
value = va_arg(arg, unsigned int);
/* Verify that a legal initial value was selected. */
if (value <= SEM_VALUE_MAX)
{
/* Allocate memory for the new semaphore */
psem = (FAR nsem_t*)kmm_malloc((sizeof(nsem_t) + namelen + 1));
if (psem)
{
/* Initialize the named semaphore */
sem = &psem->sem;
sem_init(sem, 0, value);
psem->nconnect = 1;
psem->unlinked = false;
psem->name = (FAR char*)psem + sizeof(nsem_t);
strcpy(psem->name, name);
/* Add the new semaphore to the list of named
* semaphores
*/
dq_addfirst((FAR dq_entry_t*)psem, &g_nsems);
}
/* Clean-up variable argument stuff */
va_end(arg);
}
}
}
int task_restart(pid_t pid)
{
FAR _TCB *rtcb;
FAR _TCB *tcb;
int status;
irqstate_t state;
/* Make sure this task does not become ready-to-run while
* we are futzing with its TCB
*/
sched_lock();
/* Check if the task to restart is the calling task */
rtcb = (FAR _TCB*)g_readytorun.head;
if ((pid == 0) || (pid == rtcb->pid))
{
/* Not implemented */
return ERROR;
}
/* We are restarting some other task than ourselves */
else
{
/* Find for the TCB associated with matching pid */
tcb = sched_gettcb(pid);
if (!tcb)
{
/* There is no TCB with this pid */
return ERROR;
}
/* Remove the TCB from whatever list it is in. At this point, the
* TCB should no longer be accessible to the system
*/
state = irqsave();
dq_rem((FAR dq_entry_t*)tcb, (dq_queue_t*)g_tasklisttable[tcb->task_state].list);
tcb->task_state = TSTATE_TASK_INVALID;
irqrestore(state);
/* Deallocate anything left in the TCB's queues */
sig_cleanup(tcb); /* Deallocate Signal lists */
/* Reset the current task priority */
tcb->sched_priority = tcb->init_priority;
/* Reset the base task priority and the number of pending reprioritizations */
#ifdef CONFIG_PRIORITY_INHERITANCE
tcb->base_priority = tcb->init_priority;
# if CONFIG_SEM_NNESTPRIO > 0
tcb->npend_reprio = 0;
# endif
#endif
/* Re-initialize the processor-specific portion of the TCB
* This will reset the entry point and the start-up parameters
*/
up_initial_state(tcb);
/* Add the task to the inactive task list */
dq_addfirst((FAR dq_entry_t*)tcb, (dq_queue_t*)&g_inactivetasks);
tcb->task_state = TSTATE_TASK_INACTIVE;
/* Activate the task */
status = task_activate(tcb);
if (status != OK)
{
dq_rem((FAR dq_entry_t*)tcb, (dq_queue_t*)&g_inactivetasks);
sched_releasetcb(tcb);
return ERROR;
}
}
sched_unlock();
return OK;
}
int task_restart(pid_t pid)
{
FAR struct tcb_s *rtcb;
FAR struct task_tcb_s *tcb;
FAR dq_queue_t *tasklist;
irqstate_t state;
int status;
/* Make sure this task does not become ready-to-run while
* we are futzing with its TCB
*/
sched_lock();
/* Check if the task to restart is the calling task */
rtcb = this_task();
if ((pid == 0) || (pid == rtcb->pid))
{
/* Not implemented */
set_errno(ENOSYS);
return ERROR;
}
#ifdef CONFIG_SMP
/* There is currently no capability to restart a task that is actively
* running on another CPU either. This is not the calling cast so if it
* is running, then it could only be running a a different CPU.
*
* Also, will need some interlocks to assure that no tasks are rescheduled
* on any other CPU while we do this.
*/
#warning Missing SMP logic
if (rtcb->task_state == TSTATE_TASK_RUNNING)
{
/* Not implemented */
set_errno(ENOSYS);
return ERROR;
}
#endif
/* We are restarting some other task than ourselves */
/* Find for the TCB associated with matching pid */
tcb = (FAR struct task_tcb_s *)sched_gettcb(pid);
#ifndef CONFIG_DISABLE_PTHREAD
if (!tcb || (tcb->cmn.flags & TCB_FLAG_TTYPE_MASK) == TCB_FLAG_TTYPE_PTHREAD)
#else
if (!tcb)
#endif
{
/* There is no TCB with this pid or, if there is, it is not a task. */
set_errno(ESRCH);
return ERROR;
}
/* Try to recover from any bad states */
task_recover((FAR struct tcb_s *)tcb);
/* Kill any children of this thread */
#ifdef HAVE_GROUP_MEMBERS
(void)group_killchildren(tcb);
#endif
/* Remove the TCB from whatever list it is in. After this point, the TCB
* should no longer be accessible to the system
*/
#ifdef CONFIG_SMP
tasklist = TLIST_HEAD(tcb->cmn.task_state, tcb->cmn.cpu);
#else
tasklist = TLIST_HEAD(tcb->cmn.task_state);
#endif
state = irqsave();
dq_rem((FAR dq_entry_t *)tcb, tasklist);
tcb->cmn.task_state = TSTATE_TASK_INVALID;
irqrestore(state);
/* Deallocate anything left in the TCB's queues */
sig_cleanup((FAR struct tcb_s *)tcb); /* Deallocate Signal lists */
/* Reset the current task priority */
tcb->cmn.sched_priority = tcb->init_priority;
/* Reset the base task priority and the number of pending reprioritizations */
#ifdef CONFIG_PRIORITY_INHERITANCE
tcb->cmn.base_priority = tcb->init_priority;
# if CONFIG_SEM_NNESTPRIO > 0
tcb->cmn.npend_reprio = 0;
# endif
#endif
/* Re-initialize the processor-specific portion of the TCB. This will
* reset the entry point and the start-up parameters
*/
up_initial_state((FAR struct tcb_s *)tcb);
/* Add the task to the inactive task list */
dq_addfirst((FAR dq_entry_t *)tcb, (FAR dq_queue_t *)&g_inactivetasks);
tcb->cmn.task_state = TSTATE_TASK_INACTIVE;
/* Activate the task */
status = task_activate((FAR struct tcb_s *)tcb);
if (status != OK)
{
(void)task_delete(pid);
set_errno(-status);
return ERROR;
}
sched_unlock();
return OK;
}
int task_restart(pid_t pid)
{
FAR struct tcb_s *rtcb;
FAR struct task_tcb_s *tcb;
FAR dq_queue_t *tasklist;
irqstate_t flags;
int errcode;
#ifdef CONFIG_SMP
int cpu;
#endif
int ret;
/* Check if the task to restart is the calling task */
rtcb = this_task();
if ((pid == 0) || (pid == rtcb->pid))
{
/* Not implemented */
errcode = ENOSYS;
goto errout;
}
/* We are restarting some other task than ourselves. Make sure that the
* task does not change its state while we are executing. In the single
* CPU state this could be done by disabling pre-emption. But we will
* a little stronger medicine on the SMP case: The task make be running
* on another CPU.
*/
flags = enter_critical_section();
/* Find for the TCB associated with matching pid */
tcb = (FAR struct task_tcb_s *)sched_gettcb(pid);
#ifndef CONFIG_DISABLE_PTHREAD
if (!tcb || (tcb->cmn.flags & TCB_FLAG_TTYPE_MASK) == TCB_FLAG_TTYPE_PTHREAD)
#else
if (!tcb)
#endif
{
/* There is no TCB with this pid or, if there is, it is not a task. */
errcode = ESRCH;
goto errout_with_lock;
}
#ifdef CONFIG_SMP
/* If the task is running on another CPU, then pause that CPU. We can
* then manipulate the TCB of the restarted task and when we resume the
* that CPU, the restart take effect.
*/
cpu = sched_cpu_pause(&tcb->cmn);
#endif /* CONFIG_SMP */
/* Try to recover from any bad states */
task_recover((FAR struct tcb_s *)tcb);
/* Kill any children of this thread */
#ifdef HAVE_GROUP_MEMBERS
(void)group_killchildren(tcb);
#endif
/* Remove the TCB from whatever list it is in. After this point, the TCB
* should no longer be accessible to the system
*/
#ifdef CONFIG_SMP
tasklist = TLIST_HEAD(tcb->cmn.task_state, tcb->cmn.cpu);
#else
tasklist = TLIST_HEAD(tcb->cmn.task_state);
#endif
dq_rem((FAR dq_entry_t *)tcb, tasklist);
tcb->cmn.task_state = TSTATE_TASK_INVALID;
/* Deallocate anything left in the TCB's queues */
sig_cleanup((FAR struct tcb_s *)tcb); /* Deallocate Signal lists */
/* Reset the current task priority */
tcb->cmn.sched_priority = tcb->cmn.init_priority;
/* The task should restart with pre-emption disabled and not in a critical
* secton.
*/
tcb->cmn.lockcount = 0;
#ifdef CONFIG_SMP
tcb->cmn.irqcount = 0;
#endif
/* Reset the base task priority and the number of pending reprioritizations */
#ifdef CONFIG_PRIORITY_INHERITANCE
tcb->cmn.base_priority = tcb->cmn.init_priority;
# if CONFIG_SEM_NNESTPRIO > 0
tcb->cmn.npend_reprio = 0;
# endif
#endif
/* Re-initialize the processor-specific portion of the TCB. This will
* reset the entry point and the start-up parameters
*/
up_initial_state((FAR struct tcb_s *)tcb);
/* Add the task to the inactive task list */
dq_addfirst((FAR dq_entry_t *)tcb, (FAR dq_queue_t *)&g_inactivetasks);
tcb->cmn.task_state = TSTATE_TASK_INACTIVE;
#ifdef CONFIG_SMP
/* Resume the paused CPU (if any) */
if (cpu >= 0)
{
ret = up_cpu_resume(cpu);
if (ret < 0)
{
errcode = -ret;
goto errout_with_lock;
}
}
#endif /* CONFIG_SMP */
leave_critical_section(flags);
/* Activate the task. */
ret = task_activate((FAR struct tcb_s *)tcb);
if (ret != OK)
{
(void)task_terminate(pid, true);
errcode = -ret;
goto errout_with_lock;
}
return OK;
errout_with_lock:
leave_critical_section(flags);
errout:
set_errno(errcode);
return ERROR;
}
void os_start(void)
{
int i;
slldbg("Entry\n");
/* Initialize all task lists */
dq_init(&g_readytorun);
dq_init(&g_pendingtasks);
dq_init(&g_waitingforsemaphore);
#ifndef CONFIG_DISABLE_SIGNALS
dq_init(&g_waitingforsignal);
#endif
#ifndef CONFIG_DISABLE_MQUEUE
dq_init(&g_waitingformqnotfull);
dq_init(&g_waitingformqnotempty);
#endif
#ifdef CONFIG_PAGING
dq_init(&g_waitingforfill);
#endif
dq_init(&g_inactivetasks);
sq_init(&g_delayeddeallocations);
/* Initialize the logic that determine unique process IDs. */
g_lastpid = 0;
for (i = 0; i < CONFIG_MAX_TASKS; i++)
{
g_pidhash[i].tcb = NULL;
g_pidhash[i].pid = INVALID_PROCESS_ID;
}
/* Assign the process ID of ZERO to the idle task */
g_pidhash[ PIDHASH(0)].tcb = &g_idletcb;
g_pidhash[ PIDHASH(0)].pid = 0;
/* Initialize a TCB for this thread of execution. NOTE: The default
* value for most components of the g_idletcb are zero. The entire
* structure is set to zero. Then only the (potentially) non-zero
* elements are initialized. NOTE: The idle task is the only task in
* that has pid == 0 and sched_priority == 0.
*/
bzero((void*)&g_idletcb, sizeof(_TCB));
g_idletcb.task_state = TSTATE_TASK_RUNNING;
g_idletcb.entry.main = (main_t)os_start;
#if CONFIG_TASK_NAME_SIZE > 0
strncpy(g_idletcb.name, g_idlename, CONFIG_TASK_NAME_SIZE-1);
g_idletcb.argv[0] = g_idletcb.name;
#else
g_idletcb.argv[0] = (char*)g_idlename;
#endif /* CONFIG_TASK_NAME_SIZE */
/* Then add the idle task's TCB to the head of the ready to run list */
dq_addfirst((FAR dq_entry_t*)&g_idletcb, (FAR dq_queue_t*)&g_readytorun);
/* Initialize the processor-specific portion of the TCB */
g_idletcb.flags = TCB_FLAG_TTYPE_KERNEL;
up_initial_state(&g_idletcb);
/* Initialize the semaphore facility(if in link). This has to be done
* very early because many subsystems depend upon fully functional
* semaphores.
*/
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (sem_initialize != NULL)
#endif
{
sem_initialize();
}
/* Initialize the memory manager */
#ifndef CONFIG_HEAP_BASE
{
FAR void *heap_start;
size_t heap_size;
up_allocate_heap(&heap_start, &heap_size);
kmm_initialize(heap_start, heap_size);
}
#else
kmm_initialize((void*)CONFIG_HEAP_BASE, CONFIG_HEAP_SIZE);
#endif
/* Initialize the interrupt handling subsystem (if included) */
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (irq_initialize != NULL)
#endif
{
irq_initialize();
}
/* Initialize the watchdog facility (if included in the link) */
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (wd_initialize != NULL)
#endif
{
wd_initialize();
}
/* Initialize the POSIX timer facility (if included in the link) */
#ifndef CONFIG_DISABLE_CLOCK
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (clock_initialize != NULL)
#endif
{
clock_initialize();
}
#endif
#ifndef CONFIG_DISABLE_POSIX_TIMERS
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (timer_initialize != NULL)
#endif
{
timer_initialize();
}
#endif
/* Initialize the signal facility (if in link) */
#ifndef CONFIG_DISABLE_SIGNALS
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (sig_initialize != NULL)
#endif
{
sig_initialize();
}
#endif
/* Initialize the named message queue facility (if in link) */
#ifndef CONFIG_DISABLE_MQUEUE
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (mq_initialize != NULL)
#endif
{
mq_initialize();
}
#endif
/* Initialize the thread-specific data facility (if in link) */
#ifndef CONFIG_DISABLE_PTHREAD
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (pthread_initialize != NULL)
#endif
{
pthread_initialize();
}
#endif
/* Initialize the file system (needed to support device drivers) */
#if CONFIG_NFILE_DESCRIPTORS > 0
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (fs_initialize != NULL)
#endif
{
fs_initialize();
}
#endif
/* Initialize the network system */
#ifdef CONFIG_NET
#if 0
if (net_initialize != NULL)
#endif
{
net_initialize();
}
#endif
/* The processor specific details of running the operating system
* will be handled here. Such things as setting up interrupt
* service routines and starting the clock are some of the things
* that are different for each processor and hardware platform.
*/
up_initialize();
/* Initialize the C libraries (if included in the link). This
* is done last because the libraries may depend on the above.
*/
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (lib_initialize != NULL)
#endif
{
lib_initialize();
}
/* Create stdout, stderr, stdin on the IDLE task. These will be
* inherited by all of the threads created by the IDLE task.
*/
(void)sched_setupidlefiles(&g_idletcb);
/* Create initial tasks and bring-up the system */
(void)os_bringup();
/* When control is return to this point, the system is idle. */
sdbg("Beginning Idle Loop\n");
for (;;)
{
/* Perform garbage collection (if it is not being done by the worker
* thread). This cleans-up memory de-allocations that were queued
* because they could not be freed in that execution context (for
* example, if the memory was freed from an interrupt handler).
*/
#ifndef CONFIG_SCHED_WORKQUEUE
/* We must have exclusive access to the memory manager to do this
* BUT the idle task cannot wait on a semaphore. So we only do
* the cleanup now if we can get the semaphore -- this should be
* possible because if the IDLE thread is running, no other task is!
*/
if (kmm_trysemaphore() == 0)
{
sched_garbagecollection();
kmm_givesemaphore();
}
#endif
/* Perform any processor-specific idle state operations */
up_idle();
}
}
void os_start(void)
{
int i;
slldbg("Entry\n");
/* Initialize RTOS Data ***************************************************/
/* Initialize all task lists */
dq_init(&g_readytorun);
dq_init(&g_pendingtasks);
dq_init(&g_waitingforsemaphore);
#ifndef CONFIG_DISABLE_SIGNALS
dq_init(&g_waitingforsignal);
#endif
#ifndef CONFIG_DISABLE_MQUEUE
dq_init(&g_waitingformqnotfull);
dq_init(&g_waitingformqnotempty);
#endif
#ifdef CONFIG_PAGING
dq_init(&g_waitingforfill);
#endif
dq_init(&g_inactivetasks);
sq_init(&g_delayed_kufree);
#if (defined(CONFIG_BUILD_PROTECTED) || defined(CONFIG_BUILD_KERNEL)) && \
defined(CONFIG_MM_KERNEL_HEAP)
sq_init(&g_delayed_kfree);
#endif
/* Initialize the logic that determine unique process IDs. */
g_lastpid = 0;
for (i = 0; i < CONFIG_MAX_TASKS; i++)
{
g_pidhash[i].tcb = NULL;
g_pidhash[i].pid = INVALID_PROCESS_ID;
}
/* Assign the process ID of ZERO to the idle task */
g_pidhash[PIDHASH(0)].tcb = &g_idletcb.cmn;
g_pidhash[PIDHASH(0)].pid = 0;
/* Initialize the IDLE task TCB *******************************************/
/* Initialize a TCB for this thread of execution. NOTE: The default
* value for most components of the g_idletcb are zero. The entire
* structure is set to zero. Then only the (potentially) non-zero
* elements are initialized. NOTE: The idle task is the only task in
* that has pid == 0 and sched_priority == 0.
*/
bzero((void*)&g_idletcb, sizeof(struct task_tcb_s));
g_idletcb.cmn.task_state = TSTATE_TASK_RUNNING;
g_idletcb.cmn.entry.main = (main_t)os_start;
g_idletcb.cmn.flags = TCB_FLAG_TTYPE_KERNEL;
/* Set the IDLE task name */
#if CONFIG_TASK_NAME_SIZE > 0
strncpy(g_idletcb.cmn.name, g_idlename, CONFIG_TASK_NAME_SIZE);
g_idletcb.cmn.name[CONFIG_TASK_NAME_SIZE] = '\0';
#endif /* CONFIG_TASK_NAME_SIZE */
/* Configure the task name in the argument list. The IDLE task does
* not really have an argument list, but this name is still useful
* for things like the NSH PS command.
*
* In the kernel mode build, the arguments are saved on the task's stack
* and there is no support that yet.
*/
#if CONFIG_TASK_NAME_SIZE > 0
g_idleargv[0] = g_idletcb.cmn.name;
#else
g_idleargv[0] = (FAR char *)g_idlename;
#endif /* CONFIG_TASK_NAME_SIZE */
g_idleargv[1] = NULL;
g_idletcb.argv = g_idleargv;
/* Then add the idle task's TCB to the head of the ready to run list */
dq_addfirst((FAR dq_entry_t*)&g_idletcb, (FAR dq_queue_t*)&g_readytorun);
/* Initialize the processor-specific portion of the TCB */
up_initial_state(&g_idletcb.cmn);
/* Initialize RTOS facilities *********************************************/
/* Initialize the semaphore facility. This has to be done very early
* because many subsystems depend upon fully functional semaphores.
*/
sem_initialize();
#if defined(MM_KERNEL_USRHEAP_INIT) || defined(CONFIG_MM_KERNEL_HEAP) || defined(CONFIG_MM_PGALLOC)
/* Initialize the memory manager */
{
FAR void *heap_start;
size_t heap_size;
#ifdef MM_KERNEL_USRHEAP_INIT
/* Get the user-mode heap from the platform specific code and configure
* the user-mode memory allocator.
*/
up_allocate_heap(&heap_start, &heap_size);
kumm_initialize(heap_start, heap_size);
#endif
#ifdef CONFIG_MM_KERNEL_HEAP
/* Get the kernel-mode heap from the platform specific code and configure
* the kernel-mode memory allocator.
*/
up_allocate_kheap(&heap_start, &heap_size);
kmm_initialize(heap_start, heap_size);
#endif
#ifdef CONFIG_MM_PGALLOC
/* If there is a page allocator in the configuration, then get the page
* heap information from the platform-specific code and configure the
* page allocator.
*/
up_allocate_pgheap(&heap_start, &heap_size);
mm_pginitialize(heap_start, heap_size);
#endif
}
#endif
#if defined(CONFIG_SCHED_HAVE_PARENT) && defined(CONFIG_SCHED_CHILD_STATUS)
/* Initialize tasking data structures */
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (task_initialize != NULL)
#endif
{
task_initialize();
}
#endif
/* Initialize the interrupt handling subsystem (if included) */
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (irq_initialize != NULL)
#endif
{
irq_initialize();
}
/* Initialize the watchdog facility (if included in the link) */
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (wd_initialize != NULL)
#endif
{
wd_initialize();
}
/* Initialize the POSIX timer facility (if included in the link) */
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (clock_initialize != NULL)
#endif
{
clock_initialize();
}
#ifndef CONFIG_DISABLE_POSIX_TIMERS
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (timer_initialize != NULL)
#endif
{
timer_initialize();
}
#endif
#ifndef CONFIG_DISABLE_SIGNALS
/* Initialize the signal facility (if in link) */
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (sig_initialize != NULL)
#endif
{
sig_initialize();
}
#endif
#ifndef CONFIG_DISABLE_MQUEUE
/* Initialize the named message queue facility (if in link) */
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (mq_initialize != NULL)
#endif
{
mq_initialize();
}
#endif
#ifndef CONFIG_DISABLE_PTHREAD
/* Initialize the thread-specific data facility (if in link) */
#ifdef CONFIG_HAVE_WEAKFUNCTIONS
if (pthread_initialize != NULL)
#endif
{
pthread_initialize();
}
#endif
#if CONFIG_NFILE_DESCRIPTORS > 0
/* Initialize the file system (needed to support device drivers) */
fs_initialize();
#endif
#ifdef CONFIG_NET
/* Initialize the networking system. Network initialization is
* performed in two steps: (1) net_setup() initializes static
* configuration of the network support. This must be done prior
* to registering network drivers by up_initialize(). This step
* cannot require upon any hardware-depending features such as
* timers or interrupts.
*/
net_setup();
#endif
/* The processor specific details of running the operating system
* will be handled here. Such things as setting up interrupt
* service routines and starting the clock are some of the things
* that are different for each processor and hardware platform.
*/
up_initialize();
#ifdef CONFIG_NET
/* Complete initialization the networking system now that interrupts
* and timers have been configured by up_initialize().
*/
net_initialize();
#endif
#ifdef CONFIG_MM_SHM
/* Initialize shared memory support */
shm_initialize();
#endif
/* Initialize the C libraries. This is done last because the libraries
* may depend on the above.
*/
lib_initialize();
/* IDLE Group Initialization **********************************************/
#ifdef HAVE_TASK_GROUP
/* Allocate the IDLE group */
DEBUGVERIFY(group_allocate(&g_idletcb, g_idletcb.cmn.flags));
#endif
#if CONFIG_NFILE_DESCRIPTORS > 0 || CONFIG_NSOCKET_DESCRIPTORS > 0
/* Create stdout, stderr, stdin on the IDLE task. These will be
* inherited by all of the threads created by the IDLE task.
*/
DEBUGVERIFY(group_setupidlefiles(&g_idletcb));
#endif
#ifdef HAVE_TASK_GROUP
/* Complete initialization of the IDLE group. Suppress retention
* of child status in the IDLE group.
*/
DEBUGVERIFY(group_initialize(&g_idletcb));
g_idletcb.cmn.group->tg_flags = GROUP_FLAG_NOCLDWAIT;
#endif
/* Bring Up the System ****************************************************/
/* Create initial tasks and bring-up the system */
DEBUGVERIFY(os_bringup());
/* The IDLE Loop **********************************************************/
/* When control is return to this point, the system is idle. */
sdbg("Beginning Idle Loop\n");
for (;;)
{
/* Perform garbage collection (if it is not being done by the worker
* thread). This cleans-up memory de-allocations that were queued
* because they could not be freed in that execution context (for
* example, if the memory was freed from an interrupt handler).
*/
#ifndef CONFIG_SCHED_WORKQUEUE
/* We must have exclusive access to the memory manager to do this
* BUT the idle task cannot wait on a semaphore. So we only do
* the cleanup now if we can get the semaphore -- this should be
* possible because if the IDLE thread is running, no other task is!
*
* WARNING: This logic could have undesirable side-effects if priority
* inheritance is enabled. Imaginee the possible issues if the
* priority of the IDLE thread were to get boosted! Moral: If you
* use priority inheritance, then you should also enable the work
* queue so that is done in a safer context.
*/
if (kmm_trysemaphore() == 0)
{
sched_garbagecollection();
kmm_givesemaphore();
}
#endif
/* Perform any processor-specific idle state operations */
up_idle();
}
}
int task_restart(pid_t pid)
{
FAR struct tcb_s *rtcb;
FAR struct task_tcb_s *tcb;
irqstate_t state;
int status;
/* Make sure this task does not become ready-to-run while
* we are futzing with its TCB
*/
sched_lock();
/* Check if the task to restart is the calling task */
rtcb = (FAR struct tcb_s *)g_readytorun.head;
if ((pid == 0) || (pid == rtcb->pid))
{
/* Not implemented */
set_errno(ENOSYS);
return ERROR;
}
/* We are restarting some other task than ourselves */
else
{
/* Find for the TCB associated with matching pid */
tcb = (FAR struct task_tcb_s *)sched_gettcb(pid);
#ifndef CONFIG_DISABLE_PTHREAD
if (!tcb || (tcb->cmn.flags & TCB_FLAG_TTYPE_MASK) == TCB_FLAG_TTYPE_PTHREAD)
#else
if (!tcb)
#endif
{
/* There is no TCB with this pid or, if there is, it is not a
* task.
*/
set_errno(ESRCH);
return ERROR;
}
/* Try to recover from any bad states */
task_recover((FAR struct tcb_s *)tcb);
/* Kill any children of this thread */
#if HAVE_GROUP_MEMBERS
(void)group_killchildren(tcb);
#endif
/* Remove the TCB from whatever list it is in. At this point, the
* TCB should no longer be accessible to the system
*/
state = irqsave();
dq_rem((FAR dq_entry_t*)tcb,
(dq_queue_t*)g_tasklisttable[tcb->cmn.task_state].list);
tcb->cmn.task_state = TSTATE_TASK_INVALID;
irqrestore(state);
/* Deallocate anything left in the TCB's queues */
sig_cleanup((FAR struct tcb_s *)tcb); /* Deallocate Signal lists */
/* Reset the current task priority */
tcb->cmn.sched_priority = tcb->init_priority;
/* Reset the base task priority and the number of pending reprioritizations */
#ifdef CONFIG_PRIORITY_INHERITANCE
tcb->cmn.base_priority = tcb->init_priority;
# if CONFIG_SEM_NNESTPRIO > 0
tcb->cmn.npend_reprio = 0;
# endif
#endif
/* Re-initialize the processor-specific portion of the TCB
* This will reset the entry point and the start-up parameters
*/
up_initial_state((FAR struct tcb_s *)tcb);
/* Add the task to the inactive task list */
dq_addfirst((FAR dq_entry_t*)tcb, (dq_queue_t*)&g_inactivetasks);
tcb->cmn.task_state = TSTATE_TASK_INACTIVE;
/* Activate the task */
status = task_activate((FAR struct tcb_s *)tcb);
if (status != OK)
{
(void)task_delete(pid);
set_errno(-status);
return ERROR;
}
}
sched_unlock();
return OK;
}
bool sched_removereadytorun(FAR struct tcb_s *rtcb)
{
FAR dq_queue_t *tasklist;
bool doswitch = false;
int cpu;
/* Which CPU (if any) is the task running on? Which task list holds the
* TCB?
*/
cpu = rtcb->cpu;
tasklist = TLIST_HEAD(rtcb->task_state, cpu);
/* Check if the TCB to be removed is at the head of a ready-to-run list.
* For the case of SMP, there are two lists involved: (1) the
* g_readytorun list that holds non-running tasks that have not been
* assigned to a CPU, and (2) and the g_assignedtasks[] lists which hold
* tasks assigned a CPU, including the task that is currently running on
* that CPU. Only this latter list contains the currently active task
* only only removing the head of that list can result in a context
* switch.
*
* rtcb->blink == NULL will tell us if the TCB is at the head of the
* ready-to-run list and, hence, a candidate for the new running task.
*
* If so, then the tasklist RUNNABLE attribute will inform us if the list
* holds the currently executing task and, hence, if a context switch
* should occur.
*/
if (rtcb->blink == NULL && TLIST_ISRUNNABLE(rtcb->task_state))
{
FAR struct tcb_s *nxttcb;
FAR struct tcb_s *rtrtcb;
int me;
/* There must always be at least one task in the list (the IDLE task)
* after the TCB being removed.
*/
nxttcb = (FAR struct tcb_s *)rtcb->flink;
DEBUGASSERT(nxttcb != NULL);
/* If we are modifying the head of some assigned task list other than
* our own, we will need to stop that CPU.
*/
me = this_cpu();
if (cpu != me)
{
DEBUGVERIFY(up_cpu_pause(cpu));
}
/* The task is running but the CPU that it was running on has been
* paused. We can now safely remove its TCB from the ready-to-run
* task list. In the SMP case this may be either the g_readytorun()
* or the g_assignedtasks[cpu] list.
*/
dq_rem((FAR dq_entry_t *)rtcb, tasklist);
/* Which task will go at the head of the list? It will be either the
* next tcb in the assigned task list (nxttcb) or a TCB in the
* g_readytorun list. We can only select a task from that list if
* the affinity mask includes the current CPU.
*
* REVISIT: What should we do, if anything, if pre-emption is locked
* by the another CPU? Should just used nxttcb? Should we select
* from the pending task list instead of the g_readytorun list?
*/
for (rtrtcb = (FAR struct tcb_s *)g_readytorun.head;
rtrtcb != NULL && !CPU_ISSET(cpu, &rtrtcb->affinity);
rtrtcb = (FAR struct tcb_s *)rtrtcb->flink);
/* Did we find a task in the g_readytorun list? Which task should
* we use? We decide strictly by the priority of the two tasks:
* Either (1) the task currently at the head of the g_assignedtasks[cpu]
* list (nexttcb) or (2) the highest priority task from the
* g_readytorun list with matching affinity (rtrtcb).
*/
if (rtrtcb != NULL && rtrtcb->sched_priority >= nxttcb->sched_priority)
{
FAR struct tcb_s *tmptcb;
/* The TCB at the head of the ready to run list has the higher
* priority. Remove that task from the head of the g_readytorun
* list and add to the head of the g_assignedtasks[cpu] list.
*/
tmptcb = (FAR struct tcb_s *)
dq_remfirst((FAR dq_queue_t *)&g_readytorun);
DEBUGASSERT(tmptcb == rtrtcb);
dq_addfirst((FAR dq_entry_t *)tmptcb, tasklist);
tmptcb->cpu = cpu;
nxttcb = tmptcb;
}
/* Will pre-emption be disabled after the switch? If the lockcount is
* greater than zero, then this task/this CPU holds the scheduler lock.
*/
if (nxttcb->lockcount > 0)
{
/* Yes... make sure that scheduling logic knows about this */
spin_setbit(&g_cpu_lockset, cpu, &g_cpu_locksetlock,
&g_cpu_schedlock);
}
else
{
/* No.. we may need to perform release our hold on the lock. */
spin_clrbit(&g_cpu_lockset, cpu, &g_cpu_locksetlock,
&g_cpu_schedlock);
}
/* Interrupts may be disabled after the switch. If irqcount is greater
* than zero, then this task/this CPU holds the IRQ lock
*/
if (nxttcb->irqcount > 0)
{
/* Yes... make sure that scheduling logic knows about this */
spin_setbit(&g_cpu_irqset, cpu, &g_cpu_irqsetlock,
&g_cpu_irqlock);
}
else
{
/* No.. we may need to release our hold on the irq state. */
spin_clrbit(&g_cpu_irqset, cpu, &g_cpu_irqsetlock,
&g_cpu_irqlock);
}
nxttcb->task_state = TSTATE_TASK_RUNNING;
/* All done, restart the other CPU (if it was paused). */
doswitch = true;
if (cpu != me)
{
/* In this we will not want to report a context switch to this
* CPU. Only the other CPU is affected.
*/
DEBUGVERIFY(up_cpu_resume(cpu));
doswitch = false;
}
}
else
{
/* The task is not running. Just remove its TCB from the ready-to-run
* list. In the SMP case this may be either the g_readytorun() or the
* g_assignedtasks[cpu] list.
*/
dq_rem((FAR dq_entry_t *)rtcb, tasklist);
}
/* Since the TCB is no longer in any list, it is now invalid */
rtcb->task_state = TSTATE_TASK_INVALID;
return doswitch;
}