void exit(int status)
{
_TCB *tcb = (_TCB*)g_readytorun.head;
/* Only the lower 8-bits of status are used */
status &= 0xff;
/* Perform common task termination logic */
task_exithook(tcb, status);
/* Then "really" exit. Only the lower 8 bits of the exit status are used. */
_exit(status);
}
void pthread_exit(FAR void *exit_value)
{
struct tcb_s *tcb = (struct tcb_s*)g_readytorun.head;
int status;
sdbg("exit_value=%p\n", exit_value);
/* Block any signal actions that would awaken us while were
* are performing the JOIN handshake.
*/
#ifndef CONFIG_DISABLE_SIGNALS
{
sigset_t set = ALL_SIGNAL_SET;
(void)sigprocmask(SIG_SETMASK, &set, NULL);
}
#endif
/* Complete pending join operations */
status = pthread_completejoin(getpid(), exit_value);
if (status != OK)
{
/* Assume that the join completion failured because this
* not really a pthread. Exit by calling exit().
*/
exit(EXIT_FAILURE);
}
/* Perform common task termination logic. This will get called again later
* through logic kicked off by _exit(). However, we need to call it before
* calling _exit() in order certain operations if this is the last thread
* of a task group: (2) To handle atexit() and on_exit() callbacks and
* (2) so that we can flush buffered I/O (which may required suspending).
*/
task_exithook(tcb, EXIT_SUCCESS, false);
/* Then just exit, retaining all file descriptors and without
* calling atexit() functions.
*/
_exit(EXIT_SUCCESS);
}
void exit(int status)
{
struct tcb_s *tcb = (struct tcb_s*)g_readytorun.head;
/* Only the lower 8-bits of status are used */
status &= 0xff;
/* Perform common task termination logic. This will get called again later
* through logic kicked off by _exit(). However, we need to call it before
* calling _exit() in order to handle atexit() and on_exit() callbacks and
* so that we can flush buffered I/O (both of which may required suspending).
*/
task_exithook(tcb, status, false);
/* Then "really" exit. Only the lower 8 bits of the exit status are used. */
_exit(status);
}
int task_terminate(pid_t pid, bool nonblocking)
{
FAR struct tcb_s *dtcb;
FAR dq_queue_t *tasklist;
irqstate_t flags;
#ifdef CONFIG_SMP
int cpu;
#endif
int ret;
/* Make sure the task does not become ready-to-run while we are futzing
* with its TCB. Within the critical section, no new task may be started
* or terminated (even in the SMP case).
*/
flags = enter_critical_section();
/* Find for the TCB associated with matching PID */
dtcb = sched_gettcb(pid);
if (!dtcb)
{
/* This PID does not correspond to any known task */
ret = -ESRCH;
goto errout_with_lock;
}
/* Verify our internal sanity */
#ifdef CONFIG_SMP
DEBUGASSERT(dtcb->task_state < NUM_TASK_STATES);
#else
DEBUGASSERT(dtcb->task_state != TSTATE_TASK_RUNNING &&
dtcb->task_state < NUM_TASK_STATES);
#endif
/* Remove the task from the OS's task lists. We must be in a critical
* section and the must must not be running to do this.
*/
#ifdef CONFIG_SMP
/* In the SMP case, the thread may be running on another CPU. If that is
* the case, then we will pause the CPU that the thread is running on.
*/
cpu = sched_cpu_pause(dtcb);
/* Get the task list associated with the the thread's state and CPU */
tasklist = TLIST_HEAD(dtcb->task_state, cpu);
#else
/* In the non-SMP case, we can be assured that the task to be terminated
* is not running. get the task list associated with the task state.
*/
tasklist = TLIST_HEAD(dtcb->task_state);
#endif
/* Remove the task from the task list */
dq_rem((FAR dq_entry_t *)dtcb, tasklist);
dtcb->task_state = TSTATE_TASK_INVALID;
/* At this point, the TCB should no longer be accessible to the system */
#ifdef CONFIG_SMP
/* Resume the paused CPU (if any) */
if (cpu >= 0)
{
/* I am not yet sure how to handle a failure here. */
DEBUGVERIFY(up_cpu_resume(cpu));
}
#endif /* CONFIG_SMP */
leave_critical_section(flags);
/* Perform common task termination logic (flushing streams, calling
* functions registered by at_exit/on_exit, etc.). We need to do
* this as early as possible so that higher level clean-up logic
* can run in a healthy tasking environment.
*
* In the case where the task exits via exit(), task_exithook()
* may be called twice.
*
* I suppose EXIT_SUCCESS is an appropriate return value???
*/
task_exithook(dtcb, EXIT_SUCCESS, nonblocking);
/* Since all tasks pass through this function as the final step in their
* exit sequence, this is an appropriate place to inform any instrumentation
* layer that the task no longer exists.
*/
sched_note_stop(dtcb);
/* Deallocate its TCB */
return sched_releasetcb(dtcb, dtcb->flags & TCB_FLAG_TTYPE_MASK);
errout_with_lock:
leave_critical_section(flags);
return ret;
}
