/**
* pmap_common_init
*
* Initialize common elements of pmaps.
*/
void pmap_common_init(pmap_t pmap)
{
usimple_lock_init(&pmap->lock, 0);
ledger_reference(pmap->ledger);
pmap->ref_count = 1;
pmap->nx_enabled = 0;
}
/*
* Create a new thread.
* Doesn't start the thread running.
*/
static kern_return_t
thread_create_internal(
task_t parent_task,
integer_t priority,
thread_continue_t continuation,
int options,
#define TH_OPTION_NONE 0x00
#define TH_OPTION_NOCRED 0x01
#define TH_OPTION_NOSUSP 0x02
thread_t *out_thread)
{
thread_t new_thread;
static thread_t first_thread = THREAD_NULL;
/*
* Allocate a thread and initialize static fields
*/
if (first_thread == THREAD_NULL)
new_thread = first_thread = current_thread();
new_thread = (thread_t)zalloc(thread_zone);
if (new_thread == THREAD_NULL)
return (KERN_RESOURCE_SHORTAGE);
if (new_thread != first_thread)
*new_thread = thread_template;
#ifdef MACH_BSD
new_thread->uthread = uthread_alloc(parent_task, new_thread, (options & TH_OPTION_NOCRED) != 0);
if (new_thread->uthread == NULL) {
zfree(thread_zone, new_thread);
return (KERN_RESOURCE_SHORTAGE);
}
#endif /* MACH_BSD */
if (machine_thread_create(new_thread, parent_task) != KERN_SUCCESS) {
#ifdef MACH_BSD
void *ut = new_thread->uthread;
new_thread->uthread = NULL;
/* cred free may not be necessary */
uthread_cleanup(parent_task, ut, parent_task->bsd_info);
uthread_cred_free(ut);
uthread_zone_free(ut);
#endif /* MACH_BSD */
zfree(thread_zone, new_thread);
return (KERN_FAILURE);
}
new_thread->task = parent_task;
thread_lock_init(new_thread);
wake_lock_init(new_thread);
lck_mtx_init(&new_thread->mutex, &thread_lck_grp, &thread_lck_attr);
ipc_thread_init(new_thread);
queue_init(&new_thread->held_ulocks);
new_thread->continuation = continuation;
lck_mtx_lock(&tasks_threads_lock);
task_lock(parent_task);
if ( !parent_task->active || parent_task->halting ||
((options & TH_OPTION_NOSUSP) != 0 &&
parent_task->suspend_count > 0) ||
(parent_task->thread_count >= task_threadmax &&
parent_task != kernel_task) ) {
task_unlock(parent_task);
lck_mtx_unlock(&tasks_threads_lock);
#ifdef MACH_BSD
{
void *ut = new_thread->uthread;
new_thread->uthread = NULL;
uthread_cleanup(parent_task, ut, parent_task->bsd_info);
/* cred free may not be necessary */
uthread_cred_free(ut);
uthread_zone_free(ut);
}
#endif /* MACH_BSD */
ipc_thread_disable(new_thread);
ipc_thread_terminate(new_thread);
lck_mtx_destroy(&new_thread->mutex, &thread_lck_grp);
machine_thread_destroy(new_thread);
zfree(thread_zone, new_thread);
return (KERN_FAILURE);
}
/* New threads inherit any default state on the task */
machine_thread_inherit_taskwide(new_thread, parent_task);
task_reference_internal(parent_task);
if (new_thread->task->rusage_cpu_flags & TASK_RUSECPU_FLAGS_PERTHR_LIMIT) {
/*
* This task has a per-thread CPU limit; make sure this new thread
* gets its limit set too, before it gets out of the kernel.
*/
set_astledger(new_thread);
}
new_thread->t_threadledger = LEDGER_NULL; /* per thread ledger is not inherited */
new_thread->t_ledger = new_thread->task->ledger;
if (new_thread->t_ledger)
ledger_reference(new_thread->t_ledger);
/* Cache the task's map */
new_thread->map = parent_task->map;
/* Chain the thread onto the task's list */
queue_enter(&parent_task->threads, new_thread, thread_t, task_threads);
parent_task->thread_count++;
/* So terminating threads don't need to take the task lock to decrement */
hw_atomic_add(&parent_task->active_thread_count, 1);
/* Protected by the tasks_threads_lock */
new_thread->thread_id = ++thread_unique_id;
queue_enter(&threads, new_thread, thread_t, threads);
threads_count++;
timer_call_setup(&new_thread->wait_timer, thread_timer_expire, new_thread);
timer_call_setup(&new_thread->depress_timer, thread_depress_expire, new_thread);
#if CONFIG_COUNTERS
/*
* If parent task has any reservations, they need to be propagated to this
* thread.
*/
new_thread->t_chud = (TASK_PMC_FLAG == (parent_task->t_chud & TASK_PMC_FLAG)) ?
THREAD_PMC_FLAG : 0U;
#endif
/* Set the thread's scheduling parameters */
new_thread->sched_mode = SCHED(initial_thread_sched_mode)(parent_task);
new_thread->sched_flags = 0;
new_thread->max_priority = parent_task->max_priority;
new_thread->task_priority = parent_task->priority;
new_thread->priority = (priority < 0)? parent_task->priority: priority;
if (new_thread->priority > new_thread->max_priority)
new_thread->priority = new_thread->max_priority;
#if CONFIG_EMBEDDED
if (new_thread->priority < MAXPRI_THROTTLE) {
new_thread->priority = MAXPRI_THROTTLE;
}
#endif /* CONFIG_EMBEDDED */
new_thread->importance =
new_thread->priority - new_thread->task_priority;
#if CONFIG_EMBEDDED
new_thread->saved_importance = new_thread->importance;
/* apple ios daemon starts all threads in darwin background */
if (parent_task->ext_appliedstate.apptype == PROC_POLICY_IOS_APPLE_DAEMON) {
/* Cannot use generic routines here so apply darwin bacground directly */
new_thread->policystate.hw_bg = TASK_POLICY_BACKGROUND_ATTRIBUTE_ALL;
/* set thread self backgrounding */
new_thread->appliedstate.hw_bg = new_thread->policystate.hw_bg;
/* priority will get recomputed suitably bit later */
new_thread->importance = INT_MIN;
/* to avoid changes to many pri compute routines, set the effect of those here */
new_thread->priority = MAXPRI_THROTTLE;
}
#endif /* CONFIG_EMBEDDED */
#if defined(CONFIG_SCHED_TRADITIONAL)
new_thread->sched_stamp = sched_tick;
new_thread->pri_shift = sched_pri_shift;
#endif
SCHED(compute_priority)(new_thread, FALSE);
new_thread->active = TRUE;
*out_thread = new_thread;
{
long dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4;
kdbg_trace_data(parent_task->bsd_info, &dbg_arg2);
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
TRACEDBG_CODE(DBG_TRACE_DATA, 1) | DBG_FUNC_NONE,
(vm_address_t)(uintptr_t)thread_tid(new_thread), dbg_arg2, 0, 0, 0);
kdbg_trace_string(parent_task->bsd_info,
&dbg_arg1, &dbg_arg2, &dbg_arg3, &dbg_arg4);
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
TRACEDBG_CODE(DBG_TRACE_STRING, 1) | DBG_FUNC_NONE,
dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4, 0);
}
DTRACE_PROC1(lwp__create, thread_t, *out_thread);
return (KERN_SUCCESS);
}