/*
* Copyright (c) 2000-2021 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
* @OSF_FREE_COPYRIGHT@
*/
/*
* Mach Operating System
* Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
/*
*/
/*
* File: kern/thread.c
* Author: Avadis Tevanian, Jr., Michael Wayne Young, David Golub
* Date: 1986
*
* Thread management primitives implementation.
*/
/*
* Copyright (c) 1993 The University of Utah and
* the Computer Systems Laboratory (CSL). All rights reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* THE UNIVERSITY OF UTAH AND CSL ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS
* IS" CONDITION. THE UNIVERSITY OF UTAH AND CSL DISCLAIM ANY LIABILITY OF
* ANY KIND FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* CSL requests users of this software to return to csl-dist@cs.utah.edu any
* improvements that they make and grant CSL redistribution rights.
*
*/
#include <mach/mach_types.h>
#include <mach/boolean.h>
#include <mach/policy.h>
#include <mach/thread_info.h>
#include <mach/thread_special_ports.h>
#include <mach/thread_act.h>
#include <mach/thread_status.h>
#include <mach/time_value.h>
#include <mach/vm_param.h>
#include <machine/thread.h>
#include <machine/pal_routines.h>
#include <machine/limits.h>
#include <kern/kern_types.h>
#include <kern/kalloc.h>
#include <kern/cpu_data.h>
#include <kern/extmod_statistics.h>
#include <kern/ipc_mig.h>
#include <kern/ipc_tt.h>
#include <kern/mach_param.h>
#include <kern/machine.h>
#include <kern/misc_protos.h>
#include <kern/processor.h>
#include <kern/queue.h>
#include <kern/restartable.h>
#include <kern/sched.h>
#include <kern/sched_prim.h>
#include <kern/syscall_subr.h>
#include <kern/task.h>
#include <kern/thread.h>
#include <kern/thread_group.h>
#include <kern/coalition.h>
#include <kern/host.h>
#include <kern/zalloc.h>
#include <kern/assert.h>
#include <kern/exc_resource.h>
#include <kern/exc_guard.h>
#include <kern/telemetry.h>
#include <kern/policy_internal.h>
#include <kern/turnstile.h>
#include <kern/sched_clutch.h>
#include <kern/recount.h>
#include <kern/smr.h>
#include <kern/ast.h>
#include <kern/compact_id.h>
#include <corpses/task_corpse.h>
#include <kern/kpc.h>
#if CONFIG_PERVASIVE_CPI
#include <kern/monotonic.h>
#include <machine/monotonic.h>
#endif /* CONFIG_PERVASIVE_CPI */
#include <ipc/ipc_kmsg.h>
#include <ipc/ipc_port.h>
#include <bank/bank_types.h>
#include <vm/vm_kern_xnu.h>
#include <vm/vm_pageout_xnu.h>
#include <sys/kdebug.h>
#include <sys/bsdtask_info.h>
#include <mach/sdt.h>
#include <san/kasan.h>
#include <san/kcov_stksz.h>
#include <stdatomic.h>
#if defined(HAS_APPLE_PAC)
#include <ptrauth.h>
#include <arm64/proc_reg.h>
#endif /* defined(HAS_APPLE_PAC) */
/*
* Exported interfaces
*/
#include <mach/task_server.h>
#include <mach/thread_act_server.h>
#include <mach/mach_host_server.h>
#include <mach/host_priv_server.h>
#include <mach/mach_voucher_server.h>
#include <kern/policy_internal.h>
#if CONFIG_MACF
#include <security/mac_mach_internal.h>
#endif
#include <pthread/workqueue_trace.h>
#if CONFIG_EXCLAVES
#include <mach/exclaves.h>
#endif
LCK_GRP_DECLARE(thread_lck_grp, "thread");
static SECURITY_READ_ONLY_LATE(zone_t) thread_zone;
ZONE_DEFINE_ID(ZONE_ID_THREAD_RO, "threads_ro", struct thread_ro, ZC_READONLY);
static void thread_port_with_flavor_no_senders(ipc_port_t, mach_port_mscount_t);
IPC_KOBJECT_DEFINE(IKOT_THREAD_CONTROL);
IPC_KOBJECT_DEFINE(IKOT_THREAD_READ,
.iko_op_no_senders = thread_port_with_flavor_no_senders);
IPC_KOBJECT_DEFINE(IKOT_THREAD_INSPECT,
.iko_op_no_senders = thread_port_with_flavor_no_senders);
static struct mpsc_daemon_queue thread_stack_queue;
static struct mpsc_daemon_queue thread_terminate_queue;
static struct mpsc_daemon_queue thread_deallocate_queue;
static struct mpsc_daemon_queue thread_exception_queue;
static struct mpsc_daemon_queue thread_backtrace_queue;
decl_simple_lock_data(static, crashed_threads_lock);
static queue_head_t crashed_threads_queue;
struct thread_exception_elt {
struct mpsc_queue_chain link;
exception_type_t exception_type;
task_t exception_task;
thread_t exception_thread;
};
struct thread_backtrace_elt {
struct mpsc_queue_chain link;
exception_type_t exception_type;
kcdata_object_t obj;
exception_port_t exc_ports[BT_EXC_PORTS_COUNT]; /* send rights */
};
static SECURITY_READ_ONLY_LATE(struct thread) thread_template = {
#if MACH_ASSERT
.thread_magic = THREAD_MAGIC,
#endif /* MACH_ASSERT */
.wait_result = THREAD_WAITING,
.options = THREAD_ABORTSAFE,
.state = TH_WAIT | TH_UNINT,
.th_sched_bucket = TH_BUCKET_RUN,
.base_pri = BASEPRI_DEFAULT,
.realtime.deadline = UINT64_MAX,
.last_made_runnable_time = THREAD_NOT_RUNNABLE,
.last_basepri_change_time = THREAD_NOT_RUNNABLE,
#if defined(CONFIG_SCHED_TIMESHARE_CORE)
.pri_shift = INT8_MAX,
#endif
/* timers are initialized in thread_bootstrap */
};
#define CTID_SIZE_BIT 20
#define CTID_MASK ((1u << CTID_SIZE_BIT) - 1)
#define CTID_MAX_THREAD_NUMBER (CTID_MASK - 1)
static_assert(CTID_MAX_THREAD_NUMBER <= COMPACT_ID_MAX);
#ifndef __LITTLE_ENDIAN__
#error "ctid relies on the ls bits of uint32_t to be populated"
#endif
__startup_data
static struct thread init_thread;
static SECURITY_READ_ONLY_LATE(uint32_t) ctid_nonce;
COMPACT_ID_TABLE_DEFINE(static, ctid_table);
__startup_func
static void
thread_zone_startup(void)
{
size_t size = sizeof(struct thread);
#ifdef MACH_BSD
size += roundup(uthread_size, _Alignof(struct thread));
#endif
thread_zone = zone_create_ext("threads", size,
ZC_SEQUESTER | ZC_ZFREE_CLEARMEM, ZONE_ID_THREAD, NULL);
}
STARTUP(ZALLOC, STARTUP_RANK_FOURTH, thread_zone_startup);
static void thread_deallocate_enqueue(thread_t thread);
static void thread_deallocate_complete(thread_t thread);
static void ctid_table_remove(thread_t thread);
static void ctid_table_add(thread_t thread);
static void ctid_table_init(void);
#ifdef MACH_BSD
extern void proc_exit(void *);
extern mach_exception_data_type_t proc_encode_exit_exception_code(void *);
extern uint64_t get_dispatchqueue_offset_from_proc(void *);
extern uint64_t get_return_to_kernel_offset_from_proc(void *p);
extern uint64_t get_wq_quantum_offset_from_proc(void *);
extern int proc_selfpid(void);
extern void proc_name(int, char*, int);
extern char * proc_name_address(void *p);
exception_type_t get_exception_from_corpse_crashinfo(kcdata_descriptor_t corpse_info);
extern void kdebug_proc_name_args(struct proc *proc, long args[static 4]);
#endif /* MACH_BSD */
extern bool bsdthread_part_of_cooperative_workqueue(struct uthread *uth);
extern bool disable_exc_resource;
extern bool disable_exc_resource_during_audio;
extern int audio_active;
extern int debug_task;
int thread_max = CONFIG_THREAD_MAX; /* Max number of threads */
int task_threadmax = CONFIG_THREAD_MAX;
static uint64_t thread_unique_id = 100;
struct _thread_ledger_indices thread_ledgers = { .cpu_time = -1 };
static ledger_template_t thread_ledger_template = NULL;
static void init_thread_ledgers(void);
#if CONFIG_JETSAM
void jetsam_on_ledger_cpulimit_exceeded(void);
#endif
extern int task_thread_soft_limit;
/*
* Level (in terms of percentage of the limit) at which the CPU usage monitor triggers telemetry.
*
* (ie when any thread's CPU consumption exceeds 70% of the limit, start taking user
* stacktraces, aka micro-stackshots)
*/
#define CPUMON_USTACKSHOTS_TRIGGER_DEFAULT_PCT 70
/* Percentage. Level at which we start gathering telemetry. */
static TUNABLE(uint8_t, cpumon_ustackshots_trigger_pct,
"cpumon_ustackshots_trigger_pct", CPUMON_USTACKSHOTS_TRIGGER_DEFAULT_PCT);
void __attribute__((noinline)) SENDING_NOTIFICATION__THIS_THREAD_IS_CONSUMING_TOO_MUCH_CPU(void);
#if DEVELOPMENT || DEBUG
TUNABLE_WRITEABLE(int, exc_resource_threads_enabled, "exc_resource_threads_enabled", 1);
void __attribute__((noinline)) SENDING_NOTIFICATION__TASK_HAS_TOO_MANY_THREADS(task_t, int);
#endif /* DEVELOPMENT || DEBUG */
/*
* The smallest interval over which we support limiting CPU consumption is 1ms
*/
#define MINIMUM_CPULIMIT_INTERVAL_MS 1
os_refgrp_decl(static, thread_refgrp, "thread", NULL);
static inline void
init_thread_from_template(thread_t thread)
{
/*
* In general, struct thread isn't trivially-copyable, since it may
* contain pointers to thread-specific state. This may be enforced at
* compile time on architectures that store authed + diversified
* pointers in machine_thread.
*
* In this specific case, where we're initializing a new thread from a
* thread_template, we know all diversified pointers are NULL; these are
* safe to bitwise copy.
*/
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wnontrivial-memaccess"
memcpy(thread, &thread_template, sizeof(*thread));
#pragma clang diagnostic pop
}
static void
thread_ro_create(task_t parent_task, thread_t th, thread_ro_t tro_tpl)
{
#if __x86_64__
th->t_task = parent_task;
#endif
tro_tpl->tro_owner = th;
tro_tpl->tro_task = parent_task;
th->t_tro = zalloc_ro(ZONE_ID_THREAD_RO, Z_WAITOK | Z_ZERO | Z_NOFAIL);
zalloc_ro_update_elem(ZONE_ID_THREAD_RO, th->t_tro, tro_tpl);
}
static void
thread_ro_destroy(thread_t th)
{
thread_ro_t tro = get_thread_ro(th);
#if MACH_BSD
struct ucred *cred = tro->tro_cred;
struct ucred *rcred = tro->tro_realcred;
#endif
zfree_ro(ZONE_ID_THREAD_RO, tro);
#if MACH_BSD
uthread_cred_free(cred);
uthread_cred_free(rcred);
#endif
}
__startup_func
thread_t
thread_bootstrap(void)
{
/*
* Fill in a template thread for fast initialization.
*/
timer_init(&thread_template.runnable_timer);
init_thread_from_template(&init_thread);
/* fiddle with init thread to skip asserts in set_sched_pri */
init_thread.sched_pri = MAXPRI_KERNEL;
/*
* We can't quite use ctid yet, on ARM thread_bootstrap() is called
* before we can call random or anything,
* so we just make it barely work and it will get fixed up
* when the first thread is actually made.
*/
*compact_id_resolve(&ctid_table, 0) = &init_thread;
init_thread.ctid = CTID_MASK;
return &init_thread;
}
void
thread_machine_init_template(void)
{
machine_thread_template_init(&thread_template);
}
void
thread_init(void)
{
/*
* Initialize any machine-dependent
* per-thread structures necessary.
*/
machine_thread_init();
init_thread_ledgers();
}
boolean_t
thread_is_active(thread_t thread)
{
return thread->active;
}
void
thread_corpse_continue(void)
{
thread_t thread = current_thread();
thread_terminate_internal(thread);
/*
* Handle the thread termination directly
* here instead of returning to userspace.
*/
assert(thread->active == FALSE);
thread_ast_clear(thread, AST_APC);
thread_apc_ast(thread);
panic("thread_corpse_continue");
/*NOTREACHED*/
}
__dead2
static void
thread_terminate_continue(void)
{
panic("thread_terminate_continue");
/*NOTREACHED*/
}
/*
* thread_terminate_self:
*/
void
thread_terminate_self(void)
{
thread_t thread = current_thread();
thread_ro_t tro = get_thread_ro(thread);
task_t task = tro->tro_task;
void *bsd_info = get_bsdtask_info(task);
int threadcnt;
pal_thread_terminate_self(thread);
DTRACE_PROC(lwp__exit);
thread_mtx_lock(thread);
ipc_thread_disable(thread);
thread_mtx_unlock(thread);
thread_sched_call(thread, NULL);
spl_t s = splsched();
thread_lock(thread);
thread_depress_abort_locked(thread);
/*
* Before we take the thread_lock right above,
* act_set_ast_reset_pcs() might not yet observe
* that the thread is inactive, and could have
* requested an IPI Ack.
*
* Once we unlock the thread, we know that
* act_set_ast_reset_pcs() can't fail to notice
* that thread->active is false,
* and won't set new ones.
*/
thread_reset_pcs_ack_IPI(thread);
thread_unlock(thread);
splx(s);
#if CONFIG_TASKWATCH
thead_remove_taskwatch(thread);
#endif /* CONFIG_TASKWATCH */
work_interval_thread_terminate(thread);
thread_mtx_lock(thread);
thread_policy_reset(thread);
thread_mtx_unlock(thread);
assert(thread->th_work_interval == NULL);
bank_swap_thread_bank_ledger(thread, NULL);
if (kdebug_enable && bsd_hasthreadname(get_bsdthread_info(thread))) {
char threadname[MAXTHREADNAMESIZE];
bsd_getthreadname(get_bsdthread_info(thread), threadname);
kernel_debug_string_simple(TRACE_STRING_THREADNAME_PREV, threadname);
}
uthread_cleanup(get_bsdthread_info(thread), tro);
if (kdebug_enable && bsd_info && !task_is_exec_copy(task)) {
/* trace out pid before we sign off */
long dbg_arg1 = 0;
long dbg_arg2 = 0;
kdbg_trace_data(get_bsdtask_info(task), &dbg_arg1, &dbg_arg2);
#if CONFIG_PERVASIVE_CPI
if (kdebug_debugid_enabled(DBG_MT_INSTRS_CYCLES_THR_EXIT)) {
struct recount_usage usage = { 0 };
struct recount_usage perf_only = { 0 };
boolean_t intrs_end = ml_set_interrupts_enabled(FALSE);
recount_current_thread_usage_perf_only(&usage, &perf_only);
ml_set_interrupts_enabled(intrs_end);
KDBG_RELEASE(DBG_MT_INSTRS_CYCLES_THR_EXIT,
recount_usage_instructions(&usage),
recount_usage_cycles(&usage),
recount_usage_system_time_mach(&usage),
usage.ru_metrics[RCT_LVL_USER].rm_time_mach);
#if __AMP__
KDBG_RELEASE(DBG_MT_P_INSTRS_CYCLES_THR_EXIT,
recount_usage_instructions(&perf_only),
recount_usage_cycles(&perf_only),
recount_usage_system_time_mach(&perf_only),
perf_only.ru_metrics[RCT_LVL_USER].rm_time_mach);
#endif // __AMP__
}
#endif/* CONFIG_PERVASIVE_CPI */
KDBG_RELEASE(TRACE_DATA_THREAD_TERMINATE_PID, dbg_arg1, dbg_arg2);
}
/*
* After this subtraction, this thread should never access
* task->bsd_info unless it got 0 back from the os_atomic_dec. It
* could be racing with other threads to be the last thread in the
* process, and the last thread in the process will tear down the proc
* structure and zero-out task->bsd_info.
*/
threadcnt = os_atomic_dec(&task->active_thread_count, relaxed);
#if CONFIG_COALITIONS
/*
* Leave the coalitions when last thread of task is exiting and the
* task is not a corpse.
*/
if (threadcnt == 0 && !task->corpse_info) {
coalitions_remove_task(task);
}
#endif
/*
* If we are the last thread to terminate and the task is
* associated with a BSD process, perform BSD process exit.
*/
if (threadcnt == 0 && bsd_info != NULL) {
mach_exception_data_type_t subcode = 0;
if (kdebug_enable) {
/* since we're the last thread in this process, trace out the command name too */
long args[4] = { 0 };
kdebug_proc_name_args(bsd_info, args);
#if CONFIG_PERVASIVE_CPI
if (kdebug_debugid_enabled(DBG_MT_INSTRS_CYCLES_PROC_EXIT)) {
struct recount_usage usage = { 0 };
struct recount_usage perf_only = { 0 };
recount_current_task_usage_perf_only(&usage, &perf_only);
KDBG_RELEASE(DBG_MT_INSTRS_CYCLES_PROC_EXIT,
recount_usage_instructions(&usage),
recount_usage_cycles(&usage),
recount_usage_system_time_mach(&usage),
usage.ru_metrics[RCT_LVL_USER].rm_time_mach);
#if __AMP__
KDBG_RELEASE(DBG_MT_P_INSTRS_CYCLES_PROC_EXIT,
recount_usage_instructions(&perf_only),
recount_usage_cycles(&perf_only),
recount_usage_system_time_mach(&perf_only),
perf_only.ru_metrics[RCT_LVL_USER].rm_time_mach);
#endif // __AMP__
}
#endif/* CONFIG_PERVASIVE_CPI */
KDBG_RELEASE(TRACE_STRING_PROC_EXIT, args[0], args[1], args[2], args[3]);
}
/* Get the exit reason before proc_exit */
subcode = proc_encode_exit_exception_code(bsd_info);
proc_exit(bsd_info);
bsd_info = NULL;
#if CONFIG_EXCLAVES
task_clear_conclave(task);
#endif
/*
* if there is crash info in task
* then do the deliver action since this is
* last thread for this task.
*/
if (task->corpse_info) {
/* reset all except task name port */
ipc_task_reset(task);
/* enable all task ports (name port unchanged) */
ipc_task_enable(task);
exception_type_t etype = get_exception_from_corpse_crashinfo(task->corpse_info);
task_deliver_crash_notification(task, current_thread(), etype, subcode);
}
}
if (threadcnt == 0) {
task_lock(task);
if (task_is_a_corpse_fork(task)) {
thread_wakeup((event_t)&task->active_thread_count);
}
task_unlock(task);
}
#if CONFIG_EXCLAVES
exclaves_thread_terminate(thread);
#endif
if (thread->th_vm_faults_disabled) {
panic("Thread %p terminating with vm_faults disabled.", thread);
}
s = splsched();
thread_lock(thread);
/*
* Ensure that the depress timer is no longer enqueued,
* so the timer can be safely deallocated
*
* TODO: build timer_call_cancel_wait
*/
assert((thread->sched_flags & TH_SFLAG_DEPRESSED_MASK) == 0);
uint32_t delay_us = 1;
while (thread->depress_timer_active > 0) {
thread_unlock(thread);
splx(s);
delay(delay_us++);
if (delay_us > USEC_PER_SEC) {
panic("depress timer failed to inactivate!"
"thread: %p depress_timer_active: %d",
thread, thread->depress_timer_active);
}
s = splsched();
thread_lock(thread);
}
/*
* Cancel wait timer, and wait for
* concurrent expirations.
*/
if (thread->wait_timer_armed) {
thread->wait_timer_armed = false;
if (timer_call_cancel(thread->wait_timer)) {
thread->wait_timer_active--;
}
}
delay_us = 1;
while (thread->wait_timer_active > 0) {
thread_unlock(thread);
splx(s);
delay(delay_us++);
if (delay_us > USEC_PER_SEC) {
panic("wait timer failed to inactivate!"
"thread: %p, wait_timer_active: %d, "
"wait_timer_armed: %d",
thread, thread->wait_timer_active,
thread->wait_timer_armed);
}
s = splsched();
thread_lock(thread);
}
/*
* If there is a reserved stack, release it.
*/
if (thread->reserved_stack != 0) {
stack_free_reserved(thread);
thread->reserved_stack = 0;
}
/*
* Mark thread as terminating, and block.
*/
thread->state |= TH_TERMINATE;
thread_mark_wait_locked(thread, THREAD_UNINT);
#if CONFIG_EXCLAVES
assert(thread->th_exclaves_ipc_ctx.ipcb == NULL);
assert(thread->th_exclaves_ipc_ctx.scid == 0);
assert(thread->th_exclaves_intstate == 0);
assert(thread->th_exclaves_state == 0);
#endif
assert(thread->th_work_interval_flags == TH_WORK_INTERVAL_FLAGS_NONE);
assert(thread->kern_promotion_schedpri == 0);
if (thread->rwlock_count > 0) {
panic("rwlock_count is %d for thread %p, possibly it still holds a rwlock", thread->rwlock_count, thread);
}
assert(thread->priority_floor_count == 0);
assert(thread->handoff_thread == THREAD_NULL);
assert(thread->th_work_interval == NULL);
assert(thread->t_rr_state.trr_value == 0);
assert3u(0, ==, thread->sched_flags &
(TH_SFLAG_WAITQ_PROMOTED |
TH_SFLAG_RW_PROMOTED |
TH_SFLAG_EXEC_PROMOTED |
TH_SFLAG_FLOOR_PROMOTED |
TH_SFLAG_PROMOTED |
TH_SFLAG_DEPRESS));
thread_unlock(thread);
/* splsched */
thread_block((thread_continue_t)thread_terminate_continue);
/*NOTREACHED*/
}
static bool
thread_ref_release(thread_t thread)
{
if (thread == THREAD_NULL) {
return false;
}
assert_thread_magic(thread);
return os_ref_release_raw(&thread->ref_count, &thread_refgrp) == 0;
}
/* Drop a thread refcount safely without triggering a zfree */
void
thread_deallocate_safe(thread_t thread)
{
if (__improbable(thread_ref_release(thread))) {
/* enqueue the thread for thread deallocate deamon to call thread_deallocate_complete */
thread_deallocate_enqueue(thread);
}
}
void
thread_deallocate(thread_t thread)
{
if (__improbable(thread_ref_release(thread))) {
thread_deallocate_complete(thread);
}
}
void
thread_deallocate_complete(
thread_t thread)
{
task_t task;
assert_thread_magic(thread);
assert(os_ref_get_count_raw(&thread->ref_count) == 0);
if (!(thread->state & TH_TERMINATE2)) {
panic("thread_deallocate: thread not properly terminated");
}
thread_assert_runq_null(thread);
assert(!(thread->state & TH_WAKING));
#if CONFIG_CPU_COUNTERS
kpc_thread_destroy(thread);
#endif /* CONFIG_CPU_COUNTERS */
ipc_thread_terminate(thread);
proc_thread_qos_deallocate(thread);
task = get_threadtask(thread);
#ifdef MACH_BSD
uthread_destroy(get_bsdthread_info(thread));
#endif /* MACH_BSD */
if (thread->t_ledger) {
ledger_dereference(thread->t_ledger);
}
if (thread->t_threadledger) {
ledger_dereference(thread->t_threadledger);
}
assert(thread->turnstile != TURNSTILE_NULL);
if (thread->turnstile) {
turnstile_deallocate(thread->turnstile);
}
turnstile_compact_id_put(thread->ctsid);
if (IPC_VOUCHER_NULL != thread->ith_voucher) {
ipc_voucher_release(thread->ith_voucher);
}
kfree_data(thread->thread_io_stats, sizeof(struct io_stat_info));
#if CONFIG_PREADOPT_TG
if (thread->old_preadopt_thread_group) {
thread_group_release(thread->old_preadopt_thread_group);
}
if (thread->preadopt_thread_group) {
thread_group_release(thread->preadopt_thread_group);
}
#endif /* CONFIG_PREADOPT_TG */
if (thread->kernel_stack != 0) {
stack_free(thread);
}
recount_thread_deinit(&thread->th_recount);
lck_mtx_destroy(&thread->mutex, &thread_lck_grp);
machine_thread_destroy(thread);
task_deallocate_grp(task, TASK_GRP_INTERNAL);
#if MACH_ASSERT
assert_thread_magic(thread);
thread->thread_magic = 0;
#endif /* MACH_ASSERT */
lck_mtx_lock(&tasks_threads_lock);
assert(terminated_threads_count > 0);
queue_remove(&terminated_threads, thread, thread_t, threads);
terminated_threads_count--;
lck_mtx_unlock(&tasks_threads_lock);
timer_call_free(thread->depress_timer);
timer_call_free(thread->wait_timer);
ctid_table_remove(thread);
thread_ro_destroy(thread);
zfree(thread_zone, thread);
}
/*
* thread_inspect_deallocate:
*
* Drop a thread inspection reference.
*/
void
thread_inspect_deallocate(
thread_inspect_t thread_inspect)
{
return thread_deallocate((thread_t)thread_inspect);
}
/*
* thread_read_deallocate:
*
* Drop a reference on thread read port.
*/
void
thread_read_deallocate(
thread_read_t thread_read)
{
return thread_deallocate((thread_t)thread_read);
}
/*
* thread_exception_queue_invoke:
*
* Deliver EXC_{RESOURCE,GUARD} exception
*/
static void
thread_exception_queue_invoke(mpsc_queue_chain_t elm,
__assert_only mpsc_daemon_queue_t dq)
{
struct thread_exception_elt *elt;
task_t task;
thread_t thread;
exception_type_t etype;
assert(dq == &thread_exception_queue);
elt = mpsc_queue_element(elm, struct thread_exception_elt, link);
etype = elt->exception_type;
task = elt->exception_task;
thread = elt->exception_thread;
assert_thread_magic(thread);
kfree_type(struct thread_exception_elt, elt);
/* wait for all the threads in the task to terminate */
task_lock(task);
task_wait_till_threads_terminate_locked(task);
task_unlock(task);
/* Consumes the task ref returned by task_generate_corpse_internal */
task_deallocate(task);
/* Consumes the thread ref returned by task_generate_corpse_internal */
thread_deallocate(thread);
/* Deliver the notification, also clears the corpse. */
task_deliver_crash_notification(task, thread, etype, 0);
}
static void
thread_backtrace_queue_invoke(mpsc_queue_chain_t elm,
__assert_only mpsc_daemon_queue_t dq)
{
struct thread_backtrace_elt *elt;
kcdata_object_t obj;
exception_port_t exc_ports[BT_EXC_PORTS_COUNT]; /* send rights */
exception_type_t etype;
assert(dq == &thread_backtrace_queue);
elt = mpsc_queue_element(elm, struct thread_backtrace_elt, link);
obj = elt->obj;
memcpy(exc_ports, elt->exc_ports, sizeof(ipc_port_t) * BT_EXC_PORTS_COUNT);
etype = elt->exception_type;
kfree_type(struct thread_backtrace_elt, elt);
/* Deliver to backtrace exception ports */
exception_deliver_backtrace(obj, exc_ports, etype);
/*
* Release port right and kcdata object refs given by
* task_enqueue_exception_with_corpse()
*/
for (unsigned int i = 0; i < BT_EXC_PORTS_COUNT; i++) {
ipc_port_release_send(exc_ports[i]);
}
kcdata_object_release(obj);
}
/*
* thread_exception_enqueue:
*
* Enqueue a corpse port to be delivered an EXC_{RESOURCE,GUARD}.
*/
void
thread_exception_enqueue(
task_t task,
thread_t thread,
exception_type_t etype)
{
assert(EXC_RESOURCE == etype || EXC_GUARD == etype);
struct thread_exception_elt *elt = kalloc_type(struct thread_exception_elt, Z_WAITOK | Z_NOFAIL);
elt->exception_type = etype;
elt->exception_task = task;
elt->exception_thread = thread;
mpsc_daemon_enqueue(&thread_exception_queue, &elt->link,
MPSC_QUEUE_DISABLE_PREEMPTION);
}
void
thread_backtrace_enqueue(
kcdata_object_t obj,
exception_port_t ports[static BT_EXC_PORTS_COUNT],
exception_type_t etype)
{
struct thread_backtrace_elt *elt = kalloc_type(struct thread_backtrace_elt, Z_WAITOK | Z_NOFAIL);
elt->obj = obj;
elt->exception_type = etype;
memcpy(elt->exc_ports, ports, sizeof(ipc_port_t) * BT_EXC_PORTS_COUNT);
mpsc_daemon_enqueue(&thread_backtrace_queue, &elt->link,
MPSC_QUEUE_DISABLE_PREEMPTION);
}
/*
* thread_copy_resource_info
*
* Copy the resource info counters from source
* thread to destination thread.
*/
void
thread_copy_resource_info(
thread_t dst_thread,
thread_t src_thread)
{
dst_thread->c_switch = src_thread->c_switch;
dst_thread->p_switch = src_thread->p_switch;
dst_thread->ps_switch = src_thread->ps_switch;
dst_thread->sched_time_save = src_thread->sched_time_save;
dst_thread->runnable_timer = src_thread->runnable_timer;
dst_thread->vtimer_user_save = src_thread->vtimer_user_save;
dst_thread->vtimer_prof_save = src_thread->vtimer_prof_save;
dst_thread->vtimer_rlim_save = src_thread->vtimer_rlim_save;
dst_thread->vtimer_qos_save = src_thread->vtimer_qos_save;
dst_thread->syscalls_unix = src_thread->syscalls_unix;
dst_thread->syscalls_mach = src_thread->syscalls_mach;
ledger_rollup(dst_thread->t_threadledger, src_thread->t_threadledger);
recount_thread_copy(&dst_thread->th_recount, &src_thread->th_recount);
*dst_thread->thread_io_stats = *src_thread->thread_io_stats;
}
static void
thread_terminate_queue_invoke(mpsc_queue_chain_t e,
__assert_only mpsc_daemon_queue_t dq)
{
thread_t thread = mpsc_queue_element(e, struct thread, mpsc_links);
task_t task = get_threadtask(thread);
assert(dq == &thread_terminate_queue);
task_lock(task);
/*
* if marked for crash reporting, skip reaping.
* The corpse delivery thread will clear bit and enqueue
* for reaping when done
*
* Note: the inspection field is set under the task lock
*
* FIXME[mad]: why enqueue for termination before `inspection` is false ?
*/
if (__improbable(thread->inspection)) {
simple_lock(&crashed_threads_lock, &thread_lck_grp);
task_unlock(task);
enqueue_tail(&crashed_threads_queue, &thread->runq_links);
simple_unlock(&crashed_threads_lock);
return;
}
recount_task_rollup_thread(&task->tk_recount, &thread->th_recount);
task->total_runnable_time += timer_grab(&thread->runnable_timer);
task->c_switch += thread->c_switch;
task->p_switch += thread->p_switch;
task->ps_switch += thread->ps_switch;
task->syscalls_unix += thread->syscalls_unix;
task->syscalls_mach += thread->syscalls_mach;
task->task_timer_wakeups_bin_1 += thread->thread_timer_wakeups_bin_1;
task->task_timer_wakeups_bin_2 += thread->thread_timer_wakeups_bin_2;
task->task_gpu_ns += ml_gpu_stat(thread);
task->decompressions += thread->decompressions;
thread_update_qos_cpu_time(thread);
queue_remove(&task->threads, thread, thread_t, task_threads);
task->thread_count--;
/*
* If the task is being halted, and there is only one thread
* left in the task after this one, then wakeup that thread.
*/
if (task->thread_count == 1 && task->halting) {
thread_wakeup((event_t)&task->halting);
}
task_unlock(task);
lck_mtx_lock(&tasks_threads_lock);
queue_remove(&threads, thread, thread_t, threads);
threads_count--;
queue_enter(&terminated_threads, thread, thread_t, threads);
terminated_threads_count++;
lck_mtx_unlock(&tasks_threads_lock);
#if MACH_BSD
/*
* The thread no longer counts against the task's thread count,
* we can now wake up any pending joiner.
*
* Note that the inheritor will be set to `thread` which is
* incorrect once it is on the termination queue, however
* the termination queue runs at MINPRI_KERNEL which is higher
* than any user thread, so this isn't a priority inversion.
*/
if (thread_get_tag(thread) & THREAD_TAG_USER_JOIN) {
struct uthread *uth = get_bsdthread_info(thread);
mach_port_name_t kport = uthread_joiner_port(uth);
/*
* Clear the port low two bits to tell pthread that thread is gone.
*/
#ifndef NO_PORT_GEN
kport &= ~MACH_PORT_MAKE(0, IE_BITS_GEN_MASK + IE_BITS_GEN_ONE);
#else
kport |= MACH_PORT_MAKE(0, ~(IE_BITS_GEN_MASK + IE_BITS_GEN_ONE));
#endif
(void)copyoutmap_atomic32(task->map, kport,
uthread_joiner_address(uth));
uthread_joiner_wake(task, uth);
}
#endif
thread_deallocate(thread);
}
static void
thread_deallocate_queue_invoke(mpsc_queue_chain_t e,
__assert_only mpsc_daemon_queue_t dq)
{
thread_t thread = mpsc_queue_element(e, struct thread, mpsc_links);
assert(dq == &thread_deallocate_queue);
thread_deallocate_complete(thread);
}
/*
* thread_terminate_enqueue:
*
* Enqueue a terminating thread for final disposition.
*
* Called at splsched.
*/
void
thread_terminate_enqueue(
thread_t thread)
{
KDBG_RELEASE(TRACE_DATA_THREAD_TERMINATE, thread->thread_id);
mpsc_daemon_enqueue(&thread_terminate_queue, &thread->mpsc_links,
MPSC_QUEUE_DISABLE_PREEMPTION);
}
/*
* thread_deallocate_enqueue:
*
* Enqueue a thread for final deallocation.
*/
static void
thread_deallocate_enqueue(
thread_t thread)
{
mpsc_daemon_enqueue(&thread_deallocate_queue, &thread->mpsc_links,
MPSC_QUEUE_DISABLE_PREEMPTION);
}
/*
* thread_terminate_crashed_threads:
* walk the list of crashed threads and put back set of threads
* who are no longer being inspected.
*/
void
thread_terminate_crashed_threads(void)
{
thread_t th_remove;
simple_lock(&crashed_threads_lock, &thread_lck_grp);
/*
* loop through the crashed threads queue
* to put any threads that are not being inspected anymore
*/
qe_foreach_element_safe(th_remove, &crashed_threads_queue, runq_links) {
/* make sure current_thread is never in crashed queue */
assert(th_remove != current_thread());
if (th_remove->inspection == FALSE) {
remqueue(&th_remove->runq_links);
mpsc_daemon_enqueue(&thread_terminate_queue, &th_remove->mpsc_links,
MPSC_QUEUE_NONE);
}
}
simple_unlock(&crashed_threads_lock);
}
/*
* thread_stack_queue_invoke:
*
* Perform stack allocation as required due to
* invoke failures.
*/
static void
thread_stack_queue_invoke(mpsc_queue_chain_t elm,
__assert_only mpsc_daemon_queue_t dq)
{
thread_t thread = mpsc_queue_element(elm, struct thread, mpsc_links);
assert(dq == &thread_stack_queue);
/* allocate stack with interrupts enabled so that we can call into VM */
stack_alloc(thread);
KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_SCHED, MACH_STACK_WAIT) | DBG_FUNC_END, thread_tid(thread), 0, 0, 0, 0);
spl_t s = splsched();
thread_lock(thread);
thread_setrun(thread, SCHED_PREEMPT | SCHED_TAILQ);
thread_unlock(thread);
splx(s);
}
/*
* thread_stack_enqueue:
*
* Enqueue a thread for stack allocation.
*
* Called at splsched.
*/
void
thread_stack_enqueue(
thread_t thread)
{
KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_SCHED, MACH_STACK_WAIT) | DBG_FUNC_START, thread_tid(thread), 0, 0, 0, 0);
assert_thread_magic(thread);
mpsc_daemon_enqueue(&thread_stack_queue, &thread->mpsc_links,
MPSC_QUEUE_DISABLE_PREEMPTION);
}
void
thread_daemon_init(void)
{
kern_return_t result;
thread_deallocate_daemon_init();
thread_deallocate_daemon_register_queue(&thread_terminate_queue,
thread_terminate_queue_invoke);
thread_deallocate_daemon_register_queue(&thread_deallocate_queue,
thread_deallocate_queue_invoke);
ipc_object_deallocate_register_queue();
simple_lock_init(&crashed_threads_lock, 0);
queue_init(&crashed_threads_queue);
result = mpsc_daemon_queue_init_with_thread(&thread_stack_queue,
thread_stack_queue_invoke, BASEPRI_PREEMPT_HIGH,
"daemon.thread-stack", MPSC_DAEMON_INIT_NONE);
if (result != KERN_SUCCESS) {
panic("thread_daemon_init: thread_stack_daemon");
}
result = mpsc_daemon_queue_init_with_thread(&thread_exception_queue,
thread_exception_queue_invoke, MINPRI_KERNEL,
"daemon.thread-exception", MPSC_DAEMON_INIT_NONE);
if (result != KERN_SUCCESS) {
panic("thread_daemon_init: thread_exception_daemon");
}
result = mpsc_daemon_queue_init_with_thread(&thread_backtrace_queue,
thread_backtrace_queue_invoke, MINPRI_KERNEL,
"daemon.thread-backtrace", MPSC_DAEMON_INIT_NONE);
if (result != KERN_SUCCESS) {
panic("thread_daemon_init: thread_backtrace_daemon");
}
}
__options_decl(thread_create_internal_options_t, uint32_t, {
TH_OPTION_NONE = 0x00,
TH_OPTION_NOSUSP = 0x02,
TH_OPTION_WORKQ = 0x04,
TH_OPTION_MAINTHREAD = 0x08,
});
void
main_thread_set_immovable_pinned(thread_t thread)
{
ipc_main_thread_set_immovable_pinned(thread);
}
/*
* Create a new thread.
* Doesn't start the thread running.
*
* Task and tasks_threads_lock are returned locked on success.
*/
static kern_return_t
thread_create_internal(
task_t parent_task,
integer_t priority,
thread_continue_t continuation,
void *parameter,
thread_create_internal_options_t options,
thread_t *out_thread)
{
thread_t new_thread;
ipc_thread_init_options_t init_options = IPC_THREAD_INIT_NONE;
struct thread_ro tro_tpl = { };
bool first_thread = false;
kern_return_t kr = KERN_FAILURE;
/*
* Allocate a thread and initialize static fields
*/
new_thread = zalloc_flags(thread_zone, Z_WAITOK | Z_NOFAIL);
if (__improbable(current_thread() == &init_thread)) {
/*
* The first thread ever is a global, but because we want to be
* able to zone_id_require() threads, we have to stop using the
* global piece of memory we used to boostrap the kernel and
* jump to a proper thread from a zone.
*
* This is why that one thread will inherit its original
* state differently.
*
* Also remember this thread in `vm_pageout_scan_thread`
* as this is what the first thread ever becomes.
*
* Also pre-warm the depress timer since the VM pageout scan
* daemon might need to use it.
*/
assert(vm_pageout_scan_thread == THREAD_NULL);
vm_pageout_scan_thread = new_thread;
first_thread = true;
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wnontrivial-memaccess"
/* work around 74481146 */
memcpy(new_thread, &init_thread, sizeof(*new_thread));
#pragma clang diagnostic pop
/*
* Make the ctid table functional
*/
ctid_table_init();
new_thread->ctid = 0;
} else {
init_thread_from_template(new_thread);
}
if (options & TH_OPTION_MAINTHREAD) {
init_options |= IPC_THREAD_INIT_MAINTHREAD;
}
os_ref_init_count_raw(&new_thread->ref_count, &thread_refgrp, 2);
machine_thread_create(new_thread, parent_task, first_thread);
machine_thread_process_signature(new_thread, parent_task);
#ifdef MACH_BSD
uthread_init(parent_task, get_bsdthread_info(new_thread),
&tro_tpl, (options & TH_OPTION_WORKQ) != 0);
if (!task_is_a_corpse(parent_task)) {
/*
* uthread_init will set tro_cred (with a +1)
* and tro_proc for live tasks.
*/
assert(tro_tpl.tro_cred && tro_tpl.tro_proc);
}
#endif /* MACH_BSD */
thread_lock_init(new_thread);
wake_lock_init(new_thread);
lck_mtx_init(&new_thread->mutex, &thread_lck_grp, LCK_ATTR_NULL);
ipc_thread_init(parent_task, new_thread, &tro_tpl, init_options);
thread_ro_create(parent_task, new_thread, &tro_tpl);
new_thread->continuation = continuation;
new_thread->parameter = parameter;
new_thread->inheritor_flags = TURNSTILE_UPDATE_FLAGS_NONE;
new_thread->requested_policy = default_thread_requested_policy;
new_thread->__runq.runq = PROCESSOR_NULL;
priority_queue_init(&new_thread->sched_inheritor_queue);
priority_queue_init(&new_thread->base_inheritor_queue);
#if CONFIG_SCHED_CLUTCH
priority_queue_entry_init(&new_thread->th_clutch_runq_link);
priority_queue_entry_init(&new_thread->th_clutch_pri_link);
#endif /* CONFIG_SCHED_CLUTCH */
#if CONFIG_SCHED_EDGE
new_thread->th_bound_cluster_enqueued = false;
for (cluster_shared_rsrc_type_t shared_rsrc_type = CLUSTER_SHARED_RSRC_TYPE_MIN; shared_rsrc_type < CLUSTER_SHARED_RSRC_TYPE_COUNT; shared_rsrc_type++) {
new_thread->th_shared_rsrc_enqueued[shared_rsrc_type] = false;
new_thread->th_shared_rsrc_heavy_user[shared_rsrc_type] = false;
new_thread->th_shared_rsrc_heavy_perf_control[shared_rsrc_type] = false;
}
#endif /* CONFIG_SCHED_EDGE */
new_thread->th_bound_cluster_id = THREAD_BOUND_CLUSTER_NONE;
/* Allocate I/O Statistics structure */
new_thread->thread_io_stats = kalloc_data(sizeof(struct io_stat_info),
Z_WAITOK | Z_ZERO | Z_NOFAIL);
#if KASAN_CLASSIC
kasan_init_thread(&new_thread->kasan_data);
#endif /* KASAN_CLASSIC */
#if CONFIG_KCOV
kcov_init_thread(&new_thread->kcov_data);
#endif
#if CONFIG_IOSCHED
/* Clear out the I/O Scheduling info for AppleFSCompression */
new_thread->decmp_upl = NULL;
#endif /* CONFIG_IOSCHED */
new_thread->thread_region_page_shift = 0;
#if DEVELOPMENT || DEBUG
task_lock(parent_task);
uint16_t thread_limit = parent_task->task_thread_limit;
if (exc_resource_threads_enabled &&
thread_limit > 0 &&
parent_task->thread_count >= thread_limit &&
!parent_task->task_has_crossed_thread_limit &&
!(task_is_a_corpse(parent_task))) {
int thread_count = parent_task->thread_count;
parent_task->task_has_crossed_thread_limit = TRUE;
task_unlock(parent_task);
SENDING_NOTIFICATION__TASK_HAS_TOO_MANY_THREADS(parent_task, thread_count);
} else {
task_unlock(parent_task);
}
#endif
lck_mtx_lock(&tasks_threads_lock);
task_lock(parent_task);
/*
* Fail thread creation if parent task is being torn down or has too many threads
* If the caller asked for TH_OPTION_NOSUSP, also fail if the parent task is suspended
*/
if (parent_task->active == 0 || parent_task->halting ||
(parent_task->suspend_count > 0 && (options & TH_OPTION_NOSUSP) != 0) ||
(parent_task->thread_count >= task_threadmax && parent_task != kernel_task)) {
task_unlock(parent_task);
lck_mtx_unlock(&tasks_threads_lock);
ipc_thread_disable(new_thread);
ipc_thread_terminate(new_thread);
kfree_data(new_thread->thread_io_stats,
sizeof(struct io_stat_info));
lck_mtx_destroy(&new_thread->mutex, &thread_lck_grp);
kr = KERN_FAILURE;
goto out_thread_cleanup;
}
/* Protected by the tasks_threads_lock */
new_thread->thread_id = ++thread_unique_id;
ctid_table_add(new_thread);
/* New threads inherit any default state on the task */
machine_thread_inherit_taskwide(new_thread, parent_task);
task_reference_grp(parent_task, TASK_GRP_INTERNAL);
if (parent_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.
*/
act_set_astledger(new_thread);
}
/* Instantiate a thread ledger. Do not fail thread creation if ledger creation fails. */
if ((new_thread->t_threadledger = ledger_instantiate(thread_ledger_template,
LEDGER_CREATE_INACTIVE_ENTRIES)) != LEDGER_NULL) {
ledger_entry_setactive(new_thread->t_threadledger, thread_ledgers.cpu_time);
}
new_thread->t_bankledger = LEDGER_NULL;
new_thread->t_deduct_bank_ledger_time = 0;
new_thread->t_deduct_bank_ledger_energy = 0;
new_thread->t_ledger = parent_task->ledger;
if (new_thread->t_ledger) {
ledger_reference(new_thread->t_ledger);
}
recount_thread_init(&new_thread->th_recount);
/* Cache the task's map */
new_thread->map = parent_task->map;
new_thread->depress_timer = timer_call_alloc(thread_depress_expire, new_thread);
new_thread->wait_timer = timer_call_alloc(thread_timer_expire, new_thread);
#if CONFIG_CPU_COUNTERS
kpc_thread_create(new_thread);
#endif /* CONFIG_CPU_COUNTERS */
/* Set the thread's scheduling parameters */
new_thread->sched_mode = SCHED(initial_thread_sched_mode)(parent_task);
new_thread->max_priority = parent_task->max_priority;
new_thread->task_priority = parent_task->priority;
#if CONFIG_THREAD_GROUPS
thread_group_init_thread(new_thread, parent_task);
#endif /* CONFIG_THREAD_GROUPS */
int new_priority = (priority < 0) ? parent_task->priority: priority;
new_priority = (priority < 0)? parent_task->priority: priority;
if (new_priority > new_thread->max_priority) {
new_priority = new_thread->max_priority;
}
#if !defined(XNU_TARGET_OS_OSX)
if (new_priority < MAXPRI_THROTTLE) {
new_priority = MAXPRI_THROTTLE;
}
#endif /* !defined(XNU_TARGET_OS_OSX) */
new_thread->importance = new_priority - new_thread->task_priority;
sched_set_thread_base_priority(new_thread, new_priority);
#if defined(CONFIG_SCHED_TIMESHARE_CORE)
new_thread->sched_stamp = sched_tick;
#if CONFIG_SCHED_CLUTCH
new_thread->pri_shift = sched_clutch_thread_pri_shift(new_thread, new_thread->th_sched_bucket);
#else /* CONFIG_SCHED_CLUTCH */
new_thread->pri_shift = sched_pri_shifts[new_thread->th_sched_bucket];
#endif /* CONFIG_SCHED_CLUTCH */
#endif /* defined(CONFIG_SCHED_TIMESHARE_CORE) */
if (parent_task->max_priority <= MAXPRI_THROTTLE) {
sched_thread_mode_demote(new_thread, TH_SFLAG_THROTTLED);
}
thread_policy_create(new_thread);
/* 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 */
os_atomic_inc(&parent_task->active_thread_count, relaxed);
queue_enter(&threads, new_thread, thread_t, threads);
threads_count++;
new_thread->active = TRUE;
if (task_is_a_corpse_fork(parent_task)) {
/* Set the inspection bit if the task is a corpse fork */
new_thread->inspection = TRUE;
} else {
new_thread->inspection = FALSE;
}
new_thread->corpse_dup = FALSE;
new_thread->turnstile = turnstile_alloc();
new_thread->ctsid = turnstile_compact_id_get();
*out_thread = new_thread;
if (kdebug_enable) {
long args[4] = {};
kdbg_trace_data(get_bsdtask_info(parent_task), &args[1], &args[3]);
/*
* Starting with 26604425, exec'ing creates a new task/thread.
*
* NEWTHREAD in the current process has two possible meanings:
*
* 1) Create a new thread for this process.
* 2) Create a new thread for the future process this will become in an
* exec.
*
* To disambiguate these, arg3 will be set to TRUE for case #2.
*
* The value we need to find (TPF_EXEC_COPY) is stable in the case of a
* task exec'ing. The read of t_procflags does not take the proc_lock.
*/
args[2] = task_is_exec_copy(parent_task) ? 1 : 0;
KDBG_RELEASE(TRACE_DATA_NEWTHREAD, (uintptr_t)thread_tid(new_thread),
args[1], args[2], args[3]);
kdebug_proc_name_args(get_bsdtask_info(parent_task), args);
KDBG_RELEASE(TRACE_STRING_NEWTHREAD, args[0], args[1], args[2],
args[3]);
}
DTRACE_PROC1(lwp__create, thread_t, *out_thread);
kr = KERN_SUCCESS;
goto done;
out_thread_cleanup:
#ifdef MACH_BSD
{
struct uthread *ut = get_bsdthread_info(new_thread);
uthread_cleanup(ut, &tro_tpl);
uthread_destroy(ut);
}
#endif /* MACH_BSD */
machine_thread_destroy(new_thread);
thread_ro_destroy(new_thread);
zfree(thread_zone, new_thread);
done:
return kr;
}
static kern_return_t
thread_create_with_options_internal(
task_t task,
thread_t *new_thread,
boolean_t from_user,
thread_create_internal_options_t options,
thread_continue_t continuation)
{
kern_return_t result;
thread_t thread;
if (task == TASK_NULL || task == kernel_task) {
return KERN_INVALID_ARGUMENT;
}
#if CONFIG_MACF
if (from_user && current_task() != task &&
mac_proc_check_remote_thread_create(task, -1, NULL, 0) != 0) {
return KERN_DENIED;
}
#endif
result = thread_create_internal(task, -1, continuation, NULL, options, &thread);
if (result != KERN_SUCCESS) {
return result;
}
thread->user_stop_count = 1;
thread_hold(thread);
if (task->suspend_count > 0) {
thread_hold(thread);
}
if (from_user) {
extmod_statistics_incr_thread_create(task);
}
task_unlock(task);
lck_mtx_unlock(&tasks_threads_lock);
*new_thread = thread;
return KERN_SUCCESS;
}
kern_return_t
thread_create_immovable(
task_t task,
thread_t *new_thread)
{
return thread_create_with_options_internal(task, new_thread, FALSE,
TH_OPTION_NONE, (thread_continue_t)thread_bootstrap_return);
}
kern_return_t
thread_create_from_user(
task_t task,
thread_t *new_thread)
{
/* All thread ports are created immovable by default */
return thread_create_with_options_internal(task, new_thread, TRUE, TH_OPTION_NONE,
(thread_continue_t)thread_bootstrap_return);
}
kern_return_t
thread_create_with_continuation(
task_t task,
thread_t *new_thread,
thread_continue_t continuation)
{
return thread_create_with_options_internal(task, new_thread, FALSE, TH_OPTION_NONE, continuation);
}
/*
* Create a thread that is already started, but is waiting on an event
*/
static kern_return_t
thread_create_waiting_internal(
task_t task,
thread_continue_t continuation,
event_t event,
block_hint_t block_hint,
thread_create_internal_options_t options,
thread_t *new_thread)
{
kern_return_t result;
thread_t thread;
wait_interrupt_t wait_interrupt = THREAD_INTERRUPTIBLE;
if (task == TASK_NULL || task == kernel_task) {
return KERN_INVALID_ARGUMENT;
}
result = thread_create_internal(task, -1, continuation, NULL,
options, &thread);
if (result != KERN_SUCCESS) {
return result;
}
/* note no user_stop_count or thread_hold here */
if (task->suspend_count > 0) {
thread_hold(thread);
}
thread_mtx_lock(thread);
thread_set_pending_block_hint(thread, block_hint);
if (options & TH_OPTION_WORKQ) {
thread->static_param = true;
event = workq_thread_init_and_wq_lock(task, thread);
} else if (options & TH_OPTION_MAINTHREAD) {
wait_interrupt = THREAD_UNINT;
}
thread_start_in_assert_wait(thread,
assert_wait_queue(event), CAST_EVENT64_T(event),
wait_interrupt);
thread_mtx_unlock(thread);
task_unlock(task);
lck_mtx_unlock(&tasks_threads_lock);
*new_thread = thread;
return KERN_SUCCESS;
}
kern_return_t
main_thread_create_waiting(
task_t task,
thread_continue_t continuation,
event_t event,
thread_t *new_thread)
{
return thread_create_waiting_internal(task, continuation, event,
kThreadWaitNone, TH_OPTION_MAINTHREAD, new_thread);
}
static kern_return_t
thread_create_running_internal2(
task_t task,
int flavor,
thread_state_t new_state,
mach_msg_type_number_t new_state_count,
thread_t *new_thread,
boolean_t from_user)
{
kern_return_t result;
thread_t thread;
if (task == TASK_NULL || task == kernel_task) {
return KERN_INVALID_ARGUMENT;
}
#if CONFIG_MACF
if (from_user && current_task() != task &&
mac_proc_check_remote_thread_create(task, flavor, new_state, new_state_count) != 0) {
return KERN_DENIED;
}
#endif
result = thread_create_internal(task, -1,
(thread_continue_t)thread_bootstrap_return, NULL,
TH_OPTION_NONE, &thread);
if (result != KERN_SUCCESS) {
return result;
}
if (task->suspend_count > 0) {
thread_hold(thread);
}
if (from_user) {
result = machine_thread_state_convert_from_user(thread, flavor,
new_state, new_state_count, NULL, 0, TSSF_FLAGS_NONE);
}
if (result == KERN_SUCCESS) {
result = machine_thread_set_state(thread, flavor, new_state,
new_state_count);
}
if (result != KERN_SUCCESS) {
task_unlock(task);
lck_mtx_unlock(&tasks_threads_lock);
thread_terminate(thread);
thread_deallocate(thread);
return result;
}
thread_mtx_lock(thread);
thread_start(thread);
thread_mtx_unlock(thread);
if (from_user) {
extmod_statistics_incr_thread_create(task);
}
task_unlock(task);
lck_mtx_unlock(&tasks_threads_lock);
*new_thread = thread;
return result;
}
/* Prototype, see justification above */
kern_return_t
thread_create_running(
task_t task,
int flavor,
thread_state_t new_state,
mach_msg_type_number_t new_state_count,
thread_t *new_thread);
kern_return_t
thread_create_running(
task_t task,
int flavor,
thread_state_t new_state,
mach_msg_type_number_t new_state_count,
thread_t *new_thread)
{
return thread_create_running_internal2(
task, flavor, new_state, new_state_count,
new_thread, FALSE);
}
kern_return_t
thread_create_running_from_user(
task_t task,
int flavor,
thread_state_t new_state,
mach_msg_type_number_t new_state_count,
thread_t *new_thread)
{
return thread_create_running_internal2(
task, flavor, new_state, new_state_count,
new_thread, TRUE);
}
kern_return_t
thread_create_workq_waiting(
task_t task,
thread_continue_t continuation,
thread_t *new_thread,
bool is_permanently_bound)
{
/*
* Create thread, but don't pin control port just yet, in case someone calls
* task_threads() and deallocates pinned port before kernel copyout happens,
* which will result in pinned port guard exception. Instead, pin and copyout
* atomically during workq_setup_and_run().
*/
int options = TH_OPTION_WORKQ;
/*
* Until we add a support for delayed thread creation for permanently
* bound workqueue threads, we do not pass TH_OPTION_NOSUSP for their
* creation.
*/
if (!is_permanently_bound) {
options |= TH_OPTION_NOSUSP;
}
return thread_create_waiting_internal(task, continuation, NULL,
is_permanently_bound ? kThreadWaitParkedBoundWorkQueue : kThreadWaitParkedWorkQueue,
options, new_thread);
}
/*
* kernel_thread_create:
*
* Create a thread in the kernel task
* to execute in kernel context.
*/
kern_return_t
kernel_thread_create(
thread_continue_t continuation,
void *parameter,
integer_t priority,
thread_t *new_thread)
{
kern_return_t result;
thread_t thread;
task_t task = kernel_task;
result = thread_create_internal(task, priority, continuation, parameter,
TH_OPTION_NONE, &thread);
if (result != KERN_SUCCESS) {
return result;
}
task_unlock(task);
lck_mtx_unlock(&tasks_threads_lock);
stack_alloc(thread);
assert(thread->kernel_stack != 0);
#if !defined(XNU_TARGET_OS_OSX)
if (priority > BASEPRI_KERNEL)
#endif
thread->reserved_stack = thread->kernel_stack;
if (debug_task & 1) {
kprintf("kernel_thread_create: thread = %p continuation = %p\n", thread, continuation);
}
*new_thread = thread;
return result;
}
kern_return_t
kernel_thread_start_priority(
thread_continue_t continuation,
void *parameter,
integer_t priority,
thread_t *new_thread)
{
kern_return_t result;
thread_t thread;
result = kernel_thread_create(continuation, parameter, priority, &thread);
if (result != KERN_SUCCESS) {
return result;
}
*new_thread = thread;
thread_mtx_lock(thread);
thread_start(thread);
thread_mtx_unlock(thread);
return result;
}
kern_return_t
kernel_thread_start(
thread_continue_t continuation,
void *parameter,
thread_t *new_thread)
{
return kernel_thread_start_priority(continuation, parameter, -1, new_thread);
}
/* Separated into helper function so it can be used by THREAD_BASIC_INFO and THREAD_EXTENDED_INFO */
/* it is assumed that the thread is locked by the caller */
static void
retrieve_thread_basic_info(thread_t thread, thread_basic_info_t basic_info)
{
int state, flags;
/* fill in info */
thread_read_times(thread, &basic_info->user_time,
&basic_info->system_time, NULL);
/*
* Update lazy-evaluated scheduler info because someone wants it.
*/
if (SCHED(can_update_priority)(thread)) {
SCHED(update_priority)(thread);
}
basic_info->sleep_time = 0;
/*
* To calculate cpu_usage, first correct for timer rate,
* then for 5/8 ageing. The correction factor [3/5] is
* (1/(5/8) - 1).
*/
basic_info->cpu_usage = 0;
#if defined(CONFIG_SCHED_TIMESHARE_CORE)
if (sched_tick_interval) {
basic_info->cpu_usage = (integer_t)(((uint64_t)thread->cpu_usage
* TH_USAGE_SCALE) / sched_tick_interval);
basic_info->cpu_usage = (basic_info->cpu_usage * 3) / 5;
}
#endif
if (basic_info->cpu_usage > TH_USAGE_SCALE) {
basic_info->cpu_usage = TH_USAGE_SCALE;
}
basic_info->policy = ((thread->sched_mode == TH_MODE_TIMESHARE)?
POLICY_TIMESHARE: POLICY_RR);
flags = 0;
if (thread->options & TH_OPT_IDLE_THREAD) {
flags |= TH_FLAGS_IDLE;
}
if (thread->options & TH_OPT_GLOBAL_FORCED_IDLE) {
flags |= TH_FLAGS_GLOBAL_FORCED_IDLE;
}
if (!thread->kernel_stack) {
flags |= TH_FLAGS_SWAPPED;
}
state = 0;
if (thread->state & TH_TERMINATE) {
state = TH_STATE_HALTED;
} else if (thread->state & TH_RUN) {
state = TH_STATE_RUNNING;
} else if (thread->state & TH_UNINT) {
state = TH_STATE_UNINTERRUPTIBLE;
} else if (thread->state & TH_SUSP) {
state = TH_STATE_STOPPED;
} else if (thread->state & TH_WAIT) {
state = TH_STATE_WAITING;
}
basic_info->run_state = state;
basic_info->flags = flags;
basic_info->suspend_count = thread->user_stop_count;
return;
}
kern_return_t
thread_info_internal(
thread_t thread,
thread_flavor_t flavor,
thread_info_t thread_info_out, /* ptr to OUT array */
mach_msg_type_number_t *thread_info_count) /*IN/OUT*/
{
spl_t s;
if (thread == THREAD_NULL) {
return KERN_INVALID_ARGUMENT;
}
if (flavor == THREAD_BASIC_INFO) {
if (*thread_info_count < THREAD_BASIC_INFO_COUNT) {
return KERN_INVALID_ARGUMENT;
}
s = splsched();
thread_lock(thread);
retrieve_thread_basic_info(thread, (thread_basic_info_t) thread_info_out);
thread_unlock(thread);
splx(s);
*thread_info_count = THREAD_BASIC_INFO_COUNT;
return KERN_SUCCESS;
} else if (flavor == THREAD_IDENTIFIER_INFO) {
thread_identifier_info_t identifier_info;
if (*thread_info_count < THREAD_IDENTIFIER_INFO_COUNT) {
return KERN_INVALID_ARGUMENT;
}
identifier_info = __IGNORE_WCASTALIGN((thread_identifier_info_t)thread_info_out);
s = splsched();
thread_lock(thread);
identifier_info->thread_id = thread->thread_id;
identifier_info->thread_handle = thread->machine.cthread_self;
identifier_info->dispatch_qaddr = thread_dispatchqaddr(thread);
thread_unlock(thread);
splx(s);
return KERN_SUCCESS;
} else if (flavor == THREAD_SCHED_TIMESHARE_INFO) {
policy_timeshare_info_t ts_info;
if (*thread_info_count < POLICY_TIMESHARE_INFO_COUNT) {
return KERN_INVALID_ARGUMENT;
}
ts_info = (policy_timeshare_info_t)thread_info_out;
s = splsched();
thread_lock(thread);
if (thread->sched_mode != TH_MODE_TIMESHARE) {
thread_unlock(thread);
splx(s);
return KERN_INVALID_POLICY;
}
ts_info->depressed = (thread->sched_flags & TH_SFLAG_DEPRESSED_MASK) != 0;
if (ts_info->depressed) {
ts_info->base_priority = DEPRESSPRI;
ts_info->depress_priority = thread->base_pri;
} else {
ts_info->base_priority = thread->base_pri;
ts_info->depress_priority = -1;
}
ts_info->cur_priority = thread->sched_pri;
ts_info->max_priority = thread->max_priority;
thread_unlock(thread);
splx(s);
*thread_info_count = POLICY_TIMESHARE_INFO_COUNT;
return KERN_SUCCESS;
} else if (flavor == THREAD_SCHED_FIFO_INFO) {
if (*thread_info_count < POLICY_FIFO_INFO_COUNT) {
return KERN_INVALID_ARGUMENT;
}
return KERN_INVALID_POLICY;
} else if (flavor == THREAD_SCHED_RR_INFO) {
policy_rr_info_t rr_info;
uint32_t quantum_time;
uint64_t quantum_ns;
if (*thread_info_count < POLICY_RR_INFO_COUNT) {
return KERN_INVALID_ARGUMENT;
}
rr_info = (policy_rr_info_t) thread_info_out;
s = splsched();
thread_lock(thread);
if (thread->sched_mode == TH_MODE_TIMESHARE) {
thread_unlock(thread);
splx(s);
return KERN_INVALID_POLICY;
}
rr_info->depressed = (thread->sched_flags & TH_SFLAG_DEPRESSED_MASK) != 0;
if (rr_info->depressed) {
rr_info->base_priority = DEPRESSPRI;
rr_info->depress_priority = thread->base_pri;
} else {
rr_info->base_priority = thread->base_pri;
rr_info->depress_priority = -1;
}
quantum_time = SCHED(initial_quantum_size)(THREAD_NULL);
absolutetime_to_nanoseconds(quantum_time, &quantum_ns);
rr_info->max_priority = thread->max_priority;
rr_info->quantum = (uint32_t)(quantum_ns / 1000 / 1000);
thread_unlock(thread);
splx(s);
*thread_info_count = POLICY_RR_INFO_COUNT;
return KERN_SUCCESS;
} else if (flavor == THREAD_EXTENDED_INFO) {
thread_basic_info_data_t basic_info;
thread_extended_info_t extended_info = __IGNORE_WCASTALIGN((thread_extended_info_t)thread_info_out);
if (*thread_info_count < THREAD_EXTENDED_INFO_COUNT) {
return KERN_INVALID_ARGUMENT;
}
s = splsched();
thread_lock(thread);
/* NOTE: This mimics fill_taskthreadinfo(), which is the function used by proc_pidinfo() for
* the PROC_PIDTHREADINFO flavor (which can't be used on corpses)
*/
retrieve_thread_basic_info(thread, &basic_info);
extended_info->pth_user_time = (((uint64_t)basic_info.user_time.seconds * NSEC_PER_SEC) + ((uint64_t)basic_info.user_time.microseconds * NSEC_PER_USEC));
extended_info->pth_system_time = (((uint64_t)basic_info.system_time.seconds * NSEC_PER_SEC) + ((uint64_t)basic_info.system_time.microseconds * NSEC_PER_USEC));
extended_info->pth_cpu_usage = basic_info.cpu_usage;
extended_info->pth_policy = basic_info.policy;
extended_info->pth_run_state = basic_info.run_state;
extended_info->pth_flags = basic_info.flags;
extended_info->pth_sleep_time = basic_info.sleep_time;
extended_info->pth_curpri = thread->sched_pri;
extended_info->pth_priority = thread->base_pri;
extended_info->pth_maxpriority = thread->max_priority;
bsd_getthreadname(get_bsdthread_info(thread), extended_info->pth_name);
thread_unlock(thread);
splx(s);
*thread_info_count = THREAD_EXTENDED_INFO_COUNT;
return KERN_SUCCESS;
} else if (flavor == THREAD_DEBUG_INFO_INTERNAL) {
#if DEVELOPMENT || DEBUG
thread_debug_info_internal_t dbg_info;
if (*thread_info_count < THREAD_DEBUG_INFO_INTERNAL_COUNT) {
return KERN_NOT_SUPPORTED;
}
if (thread_info_out == NULL) {
return KERN_INVALID_ARGUMENT;
}
dbg_info = __IGNORE_WCASTALIGN((thread_debug_info_internal_t)thread_info_out);
dbg_info->page_creation_count = thread->t_page_creation_count;
*thread_info_count = THREAD_DEBUG_INFO_INTERNAL_COUNT;
return KERN_SUCCESS;
#endif /* DEVELOPMENT || DEBUG */
return KERN_NOT_SUPPORTED;
}
return KERN_INVALID_ARGUMENT;
}
static void
_convert_mach_to_time_value(uint64_t time_mach, time_value_t *time)
{
clock_sec_t secs;
clock_usec_t usecs;
absolutetime_to_microtime(time_mach, &secs, &usecs);
time->seconds = (typeof(time->seconds))secs;
time->microseconds = usecs;
}
void
thread_read_times(
thread_t thread,
time_value_t *user_time,
time_value_t *system_time,
time_value_t *runnable_time)
{
if (user_time && system_time) {
struct recount_times_mach times = recount_thread_times(thread);
_convert_mach_to_time_value(times.rtm_user, user_time);
_convert_mach_to_time_value(times.rtm_system, system_time);
}
if (runnable_time) {
uint64_t runnable_time_mach = timer_grab(&thread->runnable_timer);
_convert_mach_to_time_value(runnable_time_mach, runnable_time);
}
}
uint64_t
thread_get_runtime_self(void)
{
/*
* Must be guaranteed to stay on the same CPU and not be updated by the
* scheduler.
*/
boolean_t interrupt_state = ml_set_interrupts_enabled(FALSE);
uint64_t time_mach = recount_current_thread_time_mach();
ml_set_interrupts_enabled(interrupt_state);
return time_mach;
}
/*
* thread_wire_internal:
*
* Specify that the target thread must always be able
* to run and to allocate memory.
*/
kern_return_t
thread_wire_internal(
host_priv_t host_priv,
thread_t thread,
boolean_t wired,
boolean_t *prev_state)
{
if (host_priv == NULL || thread != current_thread()) {
return KERN_INVALID_ARGUMENT;
}
if (prev_state) {
*prev_state = (thread->options & TH_OPT_VMPRIV) != 0;
}
if (wired) {
if (!(thread->options & TH_OPT_VMPRIV)) {
vm_page_free_reserve(1); /* XXX */
}
thread->options |= TH_OPT_VMPRIV;
} else {
if (thread->options & TH_OPT_VMPRIV) {
vm_page_free_reserve(-1); /* XXX */
}
thread->options &= ~TH_OPT_VMPRIV;
}
return KERN_SUCCESS;
}
/*
* thread_wire:
*
* User-api wrapper for thread_wire_internal()
*/
kern_return_t
thread_wire(
host_priv_t host_priv __unused,
thread_t thread __unused,
boolean_t wired __unused)
{
return KERN_NOT_SUPPORTED;
}
boolean_t
is_external_pageout_thread(void)
{
return current_thread() == pgo_iothread_external_state.pgo_iothread;
}
boolean_t
is_vm_privileged(void)
{
return current_thread()->options & TH_OPT_VMPRIV ? TRUE : FALSE;
}
boolean_t
set_vm_privilege(boolean_t privileged)
{
boolean_t was_vmpriv;
if (current_thread()->options & TH_OPT_VMPRIV) {
was_vmpriv = TRUE;
} else {
was_vmpriv = FALSE;
}
if (privileged != FALSE) {
current_thread()->options |= TH_OPT_VMPRIV;
} else {
current_thread()->options &= ~TH_OPT_VMPRIV;
}
return was_vmpriv;
}
void
thread_floor_boost_set_promotion_locked(thread_t thread)
{
assert(thread->priority_floor_count > 0);
if (!(thread->sched_flags & TH_SFLAG_FLOOR_PROMOTED)) {
sched_thread_promote_reason(thread, TH_SFLAG_FLOOR_PROMOTED, 0);
}
}
/*! @function thread_priority_floor_start
* @abstract boost the current thread priority to floor.
* @discussion Increase the priority of the current thread to at least MINPRI_FLOOR.
* The boost will be mantained until a corresponding thread_priority_floor_end()
* is called. Every call of thread_priority_floor_start() needs to have a corresponding
* call to thread_priority_floor_end() from the same thread.
* No thread can return to userspace before calling thread_priority_floor_end().
*
* NOTE: avoid to use this function. Try to use gate_t or sleep_with_inheritor()
* instead.
* @result a token to be given to the corresponding thread_priority_floor_end()
*/
thread_pri_floor_t
thread_priority_floor_start(void)
{
thread_pri_floor_t ret;
thread_t thread = current_thread();
__assert_only uint16_t prev_priority_floor_count;
assert(thread->priority_floor_count < UINT16_MAX);
prev_priority_floor_count = thread->priority_floor_count++;
#if MACH_ASSERT
/*
* Set the ast to check that the
* priority_floor_count is going to be set to zero when
* going back to userspace.
* Set it only once when we increment it for the first time.
*/
if (prev_priority_floor_count == 0) {
act_set_debug_assert();
}
#endif
ret.thread = thread;
return ret;
}
/*! @function thread_priority_floor_end
* @abstract ends the floor boost.
* @param token the token obtained from thread_priority_floor_start()
* @discussion ends the priority floor boost started with thread_priority_floor_start()
*/
void
thread_priority_floor_end(thread_pri_floor_t *token)
{
thread_t thread = current_thread();
assert(thread->priority_floor_count > 0);
assertf(token->thread == thread, "thread_priority_floor_end called from a different thread from thread_priority_floor_start %p %p", thread, token->thread);
if ((thread->priority_floor_count-- == 1) && (thread->sched_flags & TH_SFLAG_FLOOR_PROMOTED)) {
spl_t s = splsched();
thread_lock(thread);
if (thread->sched_flags & TH_SFLAG_FLOOR_PROMOTED) {
sched_thread_unpromote_reason(thread, TH_SFLAG_FLOOR_PROMOTED, 0);
}
thread_unlock(thread);
splx(s);
}
token->thread = NULL;
}
/*
* XXX assuming current thread only, for now...
*/
void
thread_guard_violation(thread_t thread,
mach_exception_data_type_t code, mach_exception_data_type_t subcode, boolean_t fatal)
{
assert(thread == current_thread());
/* Don't set up the AST for kernel threads; this check is needed to ensure
* that the guard_exc_* fields in the thread structure are set only by the
* current thread and therefore, don't require a lock.
*/
if (get_threadtask(thread) == kernel_task) {
return;
}
assert(EXC_GUARD_DECODE_GUARD_TYPE(code));
/*
* Use the saved state area of the thread structure
* to store all info required to handle the AST when
* returning to userspace. It's possible that there is
* already a pending guard exception. If it's non-fatal,
* it can only be over-written by a fatal exception code.
*/
if (thread->guard_exc_info.code && (thread->guard_exc_fatal || !fatal)) {
return;
}
thread->guard_exc_info.code = code;
thread->guard_exc_info.subcode = subcode;
thread->guard_exc_fatal = fatal ? 1 : 0;
spl_t s = splsched();
thread_ast_set(thread, AST_GUARD);
ast_propagate(thread);
splx(s);
}
#if CONFIG_DEBUG_SYSCALL_REJECTION
extern void rejected_syscall_guard_ast(thread_t __unused t, mach_exception_data_type_t code, mach_exception_data_type_t subcode);
#endif /* CONFIG_DEBUG_SYSCALL_REJECTION */
/*
* guard_ast:
*
* Handle AST_GUARD for a thread. This routine looks at the
* state saved in the thread structure to determine the cause
* of this exception. Based on this value, it invokes the
* appropriate routine which determines other exception related
* info and raises the exception.
*/
void
guard_ast(thread_t t)
{
const mach_exception_data_type_t
code = t->guard_exc_info.code,
subcode = t->guard_exc_info.subcode;
t->guard_exc_info.code = 0;
t->guard_exc_info.subcode = 0;
t->guard_exc_fatal = 0;
switch (EXC_GUARD_DECODE_GUARD_TYPE(code)) {
case GUARD_TYPE_NONE:
/* lingering AST_GUARD on the processor? */
break;
case GUARD_TYPE_MACH_PORT:
mach_port_guard_ast(t, code, subcode);
break;
case GUARD_TYPE_FD:
fd_guard_ast(t, code, subcode);
break;
case GUARD_TYPE_VN:
vn_guard_ast(t, code, subcode);
break;
case GUARD_TYPE_VIRT_MEMORY:
virt_memory_guard_ast(t, code, subcode);
break;
#if CONFIG_DEBUG_SYSCALL_REJECTION
case GUARD_TYPE_REJECTED_SC:
rejected_syscall_guard_ast(t, code, subcode);
break;
#endif /* CONFIG_DEBUG_SYSCALL_REJECTION */
default:
panic("guard_exc_info %llx %llx", code, subcode);
}
}
static void
thread_cputime_callback(int warning, __unused const void *arg0, __unused const void *arg1)
{
if (warning == LEDGER_WARNING_ROSE_ABOVE) {
#if CONFIG_TELEMETRY
/*
* This thread is in danger of violating the CPU usage monitor. Enable telemetry
* on the entire task so there are micro-stackshots available if and when
* EXC_RESOURCE is triggered. We could have chosen to enable micro-stackshots
* for this thread only; but now that this task is suspect, knowing what all of
* its threads are up to will be useful.
*/
telemetry_task_ctl(current_task(), TF_CPUMON_WARNING, 1);
#endif
return;
}
#if CONFIG_TELEMETRY
/*
* If the balance has dipped below the warning level (LEDGER_WARNING_DIPPED_BELOW) or
* exceeded the limit, turn telemetry off for the task.
*/
telemetry_task_ctl(current_task(), TF_CPUMON_WARNING, 0);
#endif
if (warning == 0) {
SENDING_NOTIFICATION__THIS_THREAD_IS_CONSUMING_TOO_MUCH_CPU();
}
}
void __attribute__((noinline))
SENDING_NOTIFICATION__THIS_THREAD_IS_CONSUMING_TOO_MUCH_CPU(void)
{
int pid = 0;
task_t task = current_task();
thread_t thread = current_thread();
uint64_t tid = thread->thread_id;
const char *procname = "unknown";
time_value_t thread_total_time = {0, 0};
time_value_t thread_system_time;
time_value_t thread_user_time;
int action;
uint8_t percentage;
uint32_t usage_percent = 0;
uint32_t interval_sec;
uint64_t interval_ns;
uint64_t balance_ns;
boolean_t fatal = FALSE;
boolean_t send_exc_resource = TRUE; /* in addition to RESOURCE_NOTIFY */
kern_return_t kr;
#ifdef EXC_RESOURCE_MONITORS
mach_exception_data_type_t code[EXCEPTION_CODE_MAX];
#endif /* EXC_RESOURCE_MONITORS */
struct ledger_entry_info lei;
assert(thread->t_threadledger != LEDGER_NULL);
/*
* Extract the fatal bit and suspend the monitor (which clears the bit).
*/
task_lock(task);
if (task->rusage_cpu_flags & TASK_RUSECPU_FLAGS_FATAL_CPUMON) {
fatal = TRUE;
send_exc_resource = TRUE;
}
/* Only one thread can be here at a time. Whichever makes it through
* first will successfully suspend the monitor and proceed to send the
* notification. Other threads will get an error trying to suspend the
* monitor and give up on sending the notification. In the first release,
* the monitor won't be resumed for a number of seconds, but we may
* eventually need to handle low-latency resume.
*/
kr = task_suspend_cpumon(task);
task_unlock(task);
if (kr == KERN_INVALID_ARGUMENT) {
return;
}
#ifdef MACH_BSD
pid = proc_selfpid();
void *bsd_info = get_bsdtask_info(task);
if (bsd_info != NULL) {
procname = proc_name_address(bsd_info);
}
#endif
thread_get_cpulimit(&action, &percentage, &interval_ns);
interval_sec = (uint32_t)(interval_ns / NSEC_PER_SEC);
thread_read_times(thread, &thread_user_time, &thread_system_time, NULL);
time_value_add(&thread_total_time, &thread_user_time);
time_value_add(&thread_total_time, &thread_system_time);
ledger_get_entry_info(thread->t_threadledger, thread_ledgers.cpu_time, &lei);
/* credit/debit/balance/limit are in absolute time units;
* the refill info is in nanoseconds. */
absolutetime_to_nanoseconds(lei.lei_balance, &balance_ns);
if (lei.lei_last_refill > 0) {
usage_percent = (uint32_t)((balance_ns * 100ULL) / lei.lei_last_refill);
}
/* TODO: show task total runtime (via TASK_ABSOLUTETIME_INFO)? */
printf("process %s[%d] thread %llu caught burning CPU! It used more than %d%% CPU over %u seconds\n",
procname, pid, tid, percentage, interval_sec);
printf(" (actual recent usage: %d%% over ~%llu seconds)\n",
usage_percent, (lei.lei_last_refill + NSEC_PER_SEC / 2) / NSEC_PER_SEC);
printf(" Thread lifetime cpu usage %d.%06ds, (%d.%06d user, %d.%06d sys)\n",
thread_total_time.seconds, thread_total_time.microseconds,
thread_user_time.seconds, thread_user_time.microseconds,
thread_system_time.seconds, thread_system_time.microseconds);
printf(" Ledger balance: %lld; mabs credit: %lld; mabs debit: %lld\n",
lei.lei_balance, lei.lei_credit, lei.lei_debit);
printf(" mabs limit: %llu; mabs period: %llu ns; last refill: %llu ns%s.\n",
lei.lei_limit, lei.lei_refill_period, lei.lei_last_refill,
(fatal ? " [fatal violation]" : ""));
/*
* For now, send RESOURCE_NOTIFY in parallel with EXC_RESOURCE. Once
* we have logging parity, we will stop sending EXC_RESOURCE (24508922).
*/
/* RESOURCE_NOTIFY MIG specifies nanoseconds of CPU time */
lei.lei_balance = balance_ns;
absolutetime_to_nanoseconds(lei.lei_limit, &lei.lei_limit);
trace_resource_violation(RMON_CPUUSAGE_VIOLATED, &lei);
kr = send_resource_violation(send_cpu_usage_violation, task, &lei,
fatal ? kRNFatalLimitFlag : 0);
if (kr) {
printf("send_resource_violation(CPU usage, ...): error %#x\n", kr);
}
#ifdef EXC_RESOURCE_MONITORS
if (send_exc_resource) {
if (disable_exc_resource) {
printf("process %s[%d] thread %llu caught burning CPU! "
"EXC_RESOURCE%s suppressed by a boot-arg\n",
procname, pid, tid, fatal ? " (and termination)" : "");
return;
}
if (disable_exc_resource_during_audio && audio_active) {
printf("process %s[%d] thread %llu caught burning CPU! "
"EXC_RESOURCE & termination suppressed due to audio playback\n",
procname, pid, tid);
return;
}
}
if (send_exc_resource) {
code[0] = code[1] = 0;
EXC_RESOURCE_ENCODE_TYPE(code[0], RESOURCE_TYPE_CPU);
if (fatal) {
EXC_RESOURCE_ENCODE_FLAVOR(code[0], FLAVOR_CPU_MONITOR_FATAL);
} else {
EXC_RESOURCE_ENCODE_FLAVOR(code[0], FLAVOR_CPU_MONITOR);
}
EXC_RESOURCE_CPUMONITOR_ENCODE_INTERVAL(code[0], interval_sec);
EXC_RESOURCE_CPUMONITOR_ENCODE_PERCENTAGE(code[0], percentage);
EXC_RESOURCE_CPUMONITOR_ENCODE_PERCENTAGE(code[1], usage_percent);
exception_triage(EXC_RESOURCE, code, EXCEPTION_CODE_MAX);
}
#endif /* EXC_RESOURCE_MONITORS */
if (fatal) {
#if CONFIG_JETSAM
jetsam_on_ledger_cpulimit_exceeded();
#else
task_terminate_internal(task);
#endif
}
}
bool os_variant_has_internal_diagnostics(const char *subsystem);
#if DEVELOPMENT || DEBUG
void __attribute__((noinline))
SENDING_NOTIFICATION__TASK_HAS_TOO_MANY_THREADS(task_t task, int thread_count)
{
mach_exception_data_type_t code[EXCEPTION_CODE_MAX] = {0};
int pid = task_pid(task);
char procname[MAXCOMLEN + 1] = "unknown";
if (pid == 1) {
/*
* Cannot suspend launchd
*/
return;
}
proc_name(pid, procname, sizeof(procname));
/*
* Skip all checks for testing when exc_resource_threads_enabled is overriden
*/
if (exc_resource_threads_enabled == 2) {
goto skip_checks;
}
if (disable_exc_resource) {
printf("process %s[%d] crossed thread count high watermark (%d), EXC_RESOURCE "
"suppressed by a boot-arg.\n", procname, pid, thread_count);
return;
}
if (!os_variant_has_internal_diagnostics("com.apple.xnu")) {
printf("process %s[%d] crossed thread count high watermark (%d), EXC_RESOURCE "
"suppressed, internal diagnostics disabled.\n", procname, pid, thread_count);
return;
}
if (disable_exc_resource_during_audio && audio_active) {
printf("process %s[%d] crossed thread count high watermark (%d), EXC_RESOURCE "
"suppressed due to audio playback.\n", procname, pid, thread_count);
return;
}
if (!exc_via_corpse_forking) {
printf("process %s[%d] crossed thread count high watermark (%d), EXC_RESOURCE "
"suppressed due to corpse forking being disabled.\n", procname, pid,
thread_count);
return;
}
skip_checks:
printf("process %s[%d] crossed thread count high watermark (%d), sending "
"EXC_RESOURCE\n", procname, pid, thread_count);
EXC_RESOURCE_ENCODE_TYPE(code[0], RESOURCE_TYPE_THREADS);
EXC_RESOURCE_ENCODE_FLAVOR(code[0], FLAVOR_THREADS_HIGH_WATERMARK);
EXC_RESOURCE_THREADS_ENCODE_THREADS(code[0], thread_count);
task_enqueue_exception_with_corpse(task, EXC_RESOURCE, code, EXCEPTION_CODE_MAX, NULL, FALSE);
}
#endif /* DEVELOPMENT || DEBUG */
void
thread_update_io_stats(thread_t thread, int size, int io_flags)
{
task_t task = get_threadtask(thread);
int io_tier;
if (thread->thread_io_stats == NULL || task->task_io_stats == NULL) {
return;
}
if (io_flags & DKIO_READ) {
UPDATE_IO_STATS(thread->thread_io_stats->disk_reads, size);
UPDATE_IO_STATS_ATOMIC(task->task_io_stats->disk_reads, size);
}
if (io_flags & DKIO_META) {
UPDATE_IO_STATS(thread->thread_io_stats->metadata, size);
UPDATE_IO_STATS_ATOMIC(task->task_io_stats->metadata, size);
}
if (io_flags & DKIO_PAGING) {
UPDATE_IO_STATS(thread->thread_io_stats->paging, size);
UPDATE_IO_STATS_ATOMIC(task->task_io_stats->paging, size);
}
io_tier = ((io_flags & DKIO_TIER_MASK) >> DKIO_TIER_SHIFT);
assert(io_tier < IO_NUM_PRIORITIES);
UPDATE_IO_STATS(thread->thread_io_stats->io_priority[io_tier], size);
UPDATE_IO_STATS_ATOMIC(task->task_io_stats->io_priority[io_tier], size);
/* Update Total I/O Counts */
UPDATE_IO_STATS(thread->thread_io_stats->total_io, size);
UPDATE_IO_STATS_ATOMIC(task->task_io_stats->total_io, size);
if (!(io_flags & DKIO_READ)) {
DTRACE_IO3(physical_writes, struct task *, task, uint32_t, size, int, io_flags);
ledger_credit(task->ledger, task_ledgers.physical_writes, size);
}
}
static void
init_thread_ledgers(void)
{
ledger_template_t t;
int idx;
assert(thread_ledger_template == NULL);
if ((t = ledger_template_create("Per-thread ledger")) == NULL) {
panic("couldn't create thread ledger template");
}
if ((idx = ledger_entry_add(t, "cpu_time", "sched", "ns")) < 0) {
panic("couldn't create cpu_time entry for thread ledger template");
}
if (ledger_set_callback(t, idx, thread_cputime_callback, NULL, NULL) < 0) {
panic("couldn't set thread ledger callback for cpu_time entry");
}
thread_ledgers.cpu_time = idx;
ledger_template_complete(t);
thread_ledger_template = t;
}
/*
* Returns the amount of (abs) CPU time that remains before the limit would be
* hit or the amount of time left in the current interval, whichever is smaller.
* This value changes as CPU time is consumed and the ledgers refilled.
* Used to limit the quantum of a thread.
*/
uint64_t
thread_cpulimit_remaining(uint64_t now)
{
thread_t thread = current_thread();
if ((thread->options &
(TH_OPT_PROC_CPULIMIT | TH_OPT_PRVT_CPULIMIT)) == 0) {
return UINT64_MAX;
}
/* Amount of time left in the current interval. */
const uint64_t interval_remaining =
ledger_get_interval_remaining(thread->t_threadledger, thread_ledgers.cpu_time, now);
/* Amount that can be spent until the limit is hit. */
const uint64_t remaining =
ledger_get_remaining(thread->t_threadledger, thread_ledgers.cpu_time);
return MIN(interval_remaining, remaining);
}
/*
* Returns true if a new interval should be started.
*/
bool
thread_cpulimit_interval_has_expired(uint64_t now)
{
thread_t thread = current_thread();
if ((thread->options &
(TH_OPT_PROC_CPULIMIT | TH_OPT_PRVT_CPULIMIT)) == 0) {
return false;
}
return ledger_get_interval_remaining(thread->t_threadledger,
thread_ledgers.cpu_time, now) == 0;
}
/*
* Balances the ledger and sets the last refill time to `now`.
*/
void
thread_cpulimit_restart(uint64_t now)
{
thread_t thread = current_thread();
assert3u(thread->options & (TH_OPT_PROC_CPULIMIT | TH_OPT_PRVT_CPULIMIT), !=, 0);
ledger_restart(thread->t_threadledger, thread_ledgers.cpu_time, now);
}
/*
* Returns currently applied CPU usage limit, or 0/0 if none is applied.
*/
int
thread_get_cpulimit(int *action, uint8_t *percentage, uint64_t *interval_ns)
{
int64_t abstime = 0;
uint64_t limittime = 0;
thread_t thread = current_thread();
*percentage = 0;
*interval_ns = 0;
*action = 0;
if (thread->t_threadledger == LEDGER_NULL) {
/*
* This thread has no per-thread ledger, so it can't possibly
* have a CPU limit applied.
*/
return KERN_SUCCESS;
}
ledger_get_period(thread->t_threadledger, thread_ledgers.cpu_time, interval_ns);
ledger_get_limit(thread->t_threadledger, thread_ledgers.cpu_time, &abstime);
if ((abstime == LEDGER_LIMIT_INFINITY) || (*interval_ns == 0)) {
/*
* This thread's CPU time ledger has no period or limit; so it
* doesn't have a CPU limit applied.
*/
return KERN_SUCCESS;
}
/*
* This calculation is the converse to the one in thread_set_cpulimit().
*/
absolutetime_to_nanoseconds(abstime, &limittime);
*percentage = (uint8_t)((limittime * 100ULL) / *interval_ns);
assert(*percentage <= 100);
if (thread->options & TH_OPT_PROC_CPULIMIT) {
assert((thread->options & TH_OPT_PRVT_CPULIMIT) == 0);
*action = THREAD_CPULIMIT_BLOCK;
} else if (thread->options & TH_OPT_PRVT_CPULIMIT) {
assert((thread->options & TH_OPT_PROC_CPULIMIT) == 0);
*action = THREAD_CPULIMIT_EXCEPTION;
} else {
*action = THREAD_CPULIMIT_DISABLE;
}
return KERN_SUCCESS;
}
/*
* Set CPU usage limit on a thread.
*/
int
thread_set_cpulimit(int action, uint8_t percentage, uint64_t interval_ns)
{
thread_t thread = current_thread();
ledger_t l;
uint64_t limittime = 0;
uint64_t abstime = 0;
assert(percentage <= 100);
assert(percentage > 0 || action == THREAD_CPULIMIT_DISABLE);
/*
* Disallow any change to the CPU limit if the TH_OPT_FORCED_LEDGER
* flag is set.
*/
if ((thread->options & TH_OPT_FORCED_LEDGER) != 0) {
return KERN_FAILURE;
}
if (action == THREAD_CPULIMIT_DISABLE) {
/*
* Remove CPU limit, if any exists.
*/
if (thread->t_threadledger != LEDGER_NULL) {
l = thread->t_threadledger;
ledger_set_limit(l, thread_ledgers.cpu_time, LEDGER_LIMIT_INFINITY, 0);
ledger_set_action(l, thread_ledgers.cpu_time, LEDGER_ACTION_IGNORE);
thread->options &= ~(TH_OPT_PROC_CPULIMIT | TH_OPT_PRVT_CPULIMIT);
}
return 0;
}
if (interval_ns < MINIMUM_CPULIMIT_INTERVAL_MS * NSEC_PER_MSEC) {
return KERN_INVALID_ARGUMENT;
}
l = thread->t_threadledger;
if (l == LEDGER_NULL) {
/*
* This thread doesn't yet have a per-thread ledger; so create one with the CPU time entry active.
*/
if ((l = ledger_instantiate(thread_ledger_template, LEDGER_CREATE_INACTIVE_ENTRIES)) == LEDGER_NULL) {
return KERN_RESOURCE_SHORTAGE;
}
/*
* We are the first to create this thread's ledger, so only activate our entry.
*/
ledger_entry_setactive(l, thread_ledgers.cpu_time);
thread->t_threadledger = l;
}
/*
* The limit is specified as a percentage of CPU over an interval in nanoseconds.
* Calculate the amount of CPU time that the thread needs to consume in order to hit the limit.
*/
limittime = (interval_ns * percentage) / 100;
nanoseconds_to_absolutetime(limittime, &abstime);
ledger_set_limit(l, thread_ledgers.cpu_time, abstime, cpumon_ustackshots_trigger_pct);
/*
* Refill the thread's allotted CPU time every interval_ns nanoseconds.
*/
ledger_set_period(l, thread_ledgers.cpu_time, interval_ns);
if (action == THREAD_CPULIMIT_EXCEPTION) {
/*
* We don't support programming the CPU usage monitor on a task if any of its
* threads have a per-thread blocking CPU limit configured.
*/
if (thread->options & TH_OPT_PRVT_CPULIMIT) {
panic("CPU usage monitor activated, but blocking thread limit exists");
}
/*
* Make a note that this thread's CPU limit is being used for the task-wide CPU
* usage monitor. We don't have to arm the callback which will trigger the
* exception, because that was done for us in ledger_instantiate (because the
* ledger template used has a default callback).
*/
thread->options |= TH_OPT_PROC_CPULIMIT;
} else {
/*
* We deliberately override any CPU limit imposed by a task-wide limit (eg
* CPU usage monitor).
*/
thread->options &= ~TH_OPT_PROC_CPULIMIT;
thread->options |= TH_OPT_PRVT_CPULIMIT;
/* The per-thread ledger template by default has a callback for CPU time */
ledger_disable_callback(l, thread_ledgers.cpu_time);
ledger_set_action(l, thread_ledgers.cpu_time, LEDGER_ACTION_BLOCK);
}
return 0;
}
void
thread_sched_call(
thread_t thread,
sched_call_t call)
{
assert((thread->state & TH_WAIT_REPORT) == 0);
thread->sched_call = call;
}
uint64_t
thread_tid(
thread_t thread)
{
return thread != THREAD_NULL? thread->thread_id: 0;
}
uint64_t
uthread_tid(
struct uthread *uth)
{
if (uth) {
return thread_tid(get_machthread(uth));
}
return 0;
}
uint16_t
thread_set_tag(thread_t th, uint16_t tag)
{
return thread_set_tag_internal(th, tag);
}
uint16_t
thread_get_tag(thread_t th)
{
return thread_get_tag_internal(th);
}
uint64_t
thread_last_run_time(thread_t th)
{
return th->last_run_time;
}
/*
* Shared resource contention management
*
* The scheduler attempts to load balance the shared resource intensive
* workloads across clusters to ensure that the resource is not heavily
* contended. The kernel relies on external agents (userspace or
* performance controller) to identify shared resource heavy threads.
* The load balancing is achieved based on the scheduler configuration
* enabled on the platform.
*/
#if CONFIG_SCHED_EDGE
/*
* On the Edge scheduler, the load balancing is achieved by looking
* at cluster level shared resource loads and migrating resource heavy
* threads dynamically to under utilized cluster. Therefore, when a
* thread is indicated as a resource heavy thread, the policy set
* routine simply adds a flag to the thread which is looked at by
* the scheduler on thread migration decisions.
*/
boolean_t
thread_shared_rsrc_policy_get(thread_t thread, cluster_shared_rsrc_type_t type)
{
return thread->th_shared_rsrc_heavy_user[type] || thread->th_shared_rsrc_heavy_perf_control[type];
}
__options_decl(sched_edge_rsrc_heavy_thread_state, uint32_t, {
SCHED_EDGE_RSRC_HEAVY_THREAD_SET = 1,
SCHED_EDGE_RSRC_HEAVY_THREAD_CLR = 2,
});
kern_return_t
thread_shared_rsrc_policy_set(thread_t thread, __unused uint32_t index, cluster_shared_rsrc_type_t type, shared_rsrc_policy_agent_t agent)
{
spl_t s = splsched();
thread_lock(thread);
bool user = (agent == SHARED_RSRC_POLICY_AGENT_DISPATCH) || (agent == SHARED_RSRC_POLICY_AGENT_SYSCTL);
bool *thread_flags = (user) ? thread->th_shared_rsrc_heavy_user : thread->th_shared_rsrc_heavy_perf_control;
if (thread_flags[type]) {
thread_unlock(thread);
splx(s);
return KERN_FAILURE;
}
thread_flags[type] = true;
thread_unlock(thread);
splx(s);
KDBG(MACHDBG_CODE(DBG_MACH_SCHED_CLUTCH, MACH_SCHED_EDGE_RSRC_HEAVY_THREAD) | DBG_FUNC_NONE, SCHED_EDGE_RSRC_HEAVY_THREAD_SET, thread_tid(thread), type, agent);
if (thread == current_thread()) {
if (agent == SHARED_RSRC_POLICY_AGENT_PERFCTL_QUANTUM) {
ast_on(AST_PREEMPT);
} else {
assert(agent != SHARED_RSRC_POLICY_AGENT_PERFCTL_CSW);
thread_block(THREAD_CONTINUE_NULL);
}
}
return KERN_SUCCESS;
}
kern_return_t
thread_shared_rsrc_policy_clear(thread_t thread, cluster_shared_rsrc_type_t type, shared_rsrc_policy_agent_t agent)
{
spl_t s = splsched();
thread_lock(thread);
bool user = (agent == SHARED_RSRC_POLICY_AGENT_DISPATCH) || (agent == SHARED_RSRC_POLICY_AGENT_SYSCTL);
bool *thread_flags = (user) ? thread->th_shared_rsrc_heavy_user : thread->th_shared_rsrc_heavy_perf_control;
if (!thread_flags[type]) {
thread_unlock(thread);
splx(s);
return KERN_FAILURE;
}
thread_flags[type] = false;
thread_unlock(thread);
splx(s);
KDBG(MACHDBG_CODE(DBG_MACH_SCHED_CLUTCH, MACH_SCHED_EDGE_RSRC_HEAVY_THREAD) | DBG_FUNC_NONE, SCHED_EDGE_RSRC_HEAVY_THREAD_CLR, thread_tid(thread), type, agent);
if (thread == current_thread()) {
if (agent == SHARED_RSRC_POLICY_AGENT_PERFCTL_QUANTUM) {
ast_on(AST_PREEMPT);
} else {
assert(agent != SHARED_RSRC_POLICY_AGENT_PERFCTL_CSW);
thread_block(THREAD_CONTINUE_NULL);
}
}
return KERN_SUCCESS;
}
#else /* CONFIG_SCHED_EDGE */
/*
* On non-Edge schedulers, the shared resource contention
* is managed by simply binding threads to specific clusters
* based on the worker index passed by the agents marking
* this thread as resource heavy threads. The thread binding
* approach does not provide any rebalancing opportunities;
* it can also suffer from scheduling delays if the cluster
* where the thread is bound is contended.
*/
boolean_t
thread_shared_rsrc_policy_get(__unused thread_t thread, __unused cluster_shared_rsrc_type_t type)
{
return false;
}
kern_return_t
thread_shared_rsrc_policy_set(thread_t thread, uint32_t index, __unused cluster_shared_rsrc_type_t type, __unused shared_rsrc_policy_agent_t agent)
{
return thread_bind_cluster_id(thread, index, THREAD_BIND_SOFT | THREAD_BIND_ELIGIBLE_ONLY);
}
kern_return_t
thread_shared_rsrc_policy_clear(thread_t thread, __unused cluster_shared_rsrc_type_t type, __unused shared_rsrc_policy_agent_t agent)
{
return thread_bind_cluster_id(thread, 0, THREAD_UNBIND);
}
#endif /* CONFIG_SCHED_EDGE */
uint64_t
thread_dispatchqaddr(
thread_t thread)
{
uint64_t dispatchqueue_addr;
uint64_t thread_handle;
task_t task;
if (thread == THREAD_NULL) {
return 0;
}
thread_handle = thread->machine.cthread_self;
if (thread_handle == 0) {
return 0;
}
task = get_threadtask(thread);
void *bsd_info = get_bsdtask_info(task);
if (thread->inspection == TRUE) {
dispatchqueue_addr = thread_handle + get_task_dispatchqueue_offset(task);
} else if (bsd_info) {
dispatchqueue_addr = thread_handle + get_dispatchqueue_offset_from_proc(bsd_info);
} else {
dispatchqueue_addr = 0;
}
return dispatchqueue_addr;
}
uint64_t
thread_wqquantum_addr(thread_t thread)
{
uint64_t thread_handle;
task_t task;
if (thread == THREAD_NULL) {
return 0;
}
thread_handle = thread->machine.cthread_self;
if (thread_handle == 0) {
return 0;
}
task = get_threadtask(thread);
uint64_t wq_quantum_expiry_offset = get_wq_quantum_offset_from_proc(get_bsdtask_info(task));
if (wq_quantum_expiry_offset == 0) {
return 0;
}
return wq_quantum_expiry_offset + thread_handle;
}
uint64_t
thread_rettokern_addr(
thread_t thread)
{
uint64_t rettokern_addr;
uint64_t rettokern_offset;
uint64_t thread_handle;
task_t task;
void *bsd_info;
if (thread == THREAD_NULL) {
return 0;
}
thread_handle = thread->machine.cthread_self;
if (thread_handle == 0) {
return 0;
}
task = get_threadtask(thread);
bsd_info = get_bsdtask_info(task);
if (bsd_info) {
rettokern_offset = get_return_to_kernel_offset_from_proc(bsd_info);
/* Return 0 if return to kernel offset is not initialized. */
if (rettokern_offset == 0) {
rettokern_addr = 0;
} else {
rettokern_addr = thread_handle + rettokern_offset;
}
} else {
rettokern_addr = 0;
}
return rettokern_addr;
}
/*
* Export routines to other components for things that are done as macros
* within the osfmk component.
*/
void
thread_mtx_lock(thread_t thread)
{
lck_mtx_lock(&thread->mutex);
}
void
thread_mtx_unlock(thread_t thread)
{
lck_mtx_unlock(&thread->mutex);
}
void
thread_reference(
thread_t thread)
{
if (thread != THREAD_NULL) {
zone_id_require(ZONE_ID_THREAD, sizeof(struct thread), thread);
os_ref_retain_raw(&thread->ref_count, &thread_refgrp);
}
}
void
thread_require(thread_t thread)
{
zone_id_require(ZONE_ID_THREAD, sizeof(struct thread), thread);
}
#undef thread_should_halt
boolean_t
thread_should_halt(
thread_t th)
{
return thread_should_halt_fast(th);
}
/*
* thread_set_voucher_name - reset the voucher port name bound to this thread
*
* Conditions: nothing locked
*/
kern_return_t
thread_set_voucher_name(mach_port_name_t voucher_name)
{
thread_t thread = current_thread();
ipc_voucher_t new_voucher = IPC_VOUCHER_NULL;
ipc_voucher_t voucher;
ledger_t bankledger = NULL;
struct thread_group *banktg = NULL;
uint32_t persona_id = 0;
if (MACH_PORT_DEAD == voucher_name) {
return KERN_INVALID_RIGHT;
}
/*
* agressively convert to voucher reference
*/
if (MACH_PORT_VALID(voucher_name)) {
new_voucher = convert_port_name_to_voucher(voucher_name);
if (IPC_VOUCHER_NULL == new_voucher) {
return KERN_INVALID_ARGUMENT;
}
}
bank_get_bank_ledger_thread_group_and_persona(new_voucher, &bankledger, &banktg, &persona_id);
thread_mtx_lock(thread);
voucher = thread->ith_voucher;
thread->ith_voucher_name = voucher_name;
thread->ith_voucher = new_voucher;
thread_mtx_unlock(thread);
bank_swap_thread_bank_ledger(thread, bankledger);
#if CONFIG_THREAD_GROUPS
thread_group_set_bank(thread, banktg);
#endif /* CONFIG_THREAD_GROUPS */
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
MACHDBG_CODE(DBG_MACH_IPC, MACH_THREAD_SET_VOUCHER) | DBG_FUNC_NONE,
(uintptr_t)thread_tid(thread),
(uintptr_t)voucher_name,
VM_KERNEL_ADDRPERM((uintptr_t)new_voucher),
persona_id, 0);
if (IPC_VOUCHER_NULL != voucher) {
ipc_voucher_release(voucher);
}
return KERN_SUCCESS;
}
/*
* thread_get_mach_voucher - return a voucher reference for the specified thread voucher
*
* Conditions: nothing locked
*
* NOTE: At the moment, there is no distinction between the current and effective
* vouchers because we only set them at the thread level currently.
*/
kern_return_t
thread_get_mach_voucher(
thread_act_t thread,
mach_voucher_selector_t __unused which,
ipc_voucher_t *voucherp)
{
ipc_voucher_t voucher;
if (THREAD_NULL == thread) {
return KERN_INVALID_ARGUMENT;
}
thread_mtx_lock(thread);
voucher = thread->ith_voucher;
if (IPC_VOUCHER_NULL != voucher) {
ipc_voucher_reference(voucher);
thread_mtx_unlock(thread);
*voucherp = voucher;
return KERN_SUCCESS;
}
thread_mtx_unlock(thread);
*voucherp = IPC_VOUCHER_NULL;
return KERN_SUCCESS;
}
/*
* thread_set_mach_voucher - set a voucher reference for the specified thread voucher
*
* Conditions: callers holds a reference on the voucher.
* nothing locked.
*
* We grab another reference to the voucher and bind it to the thread.
* The old voucher reference associated with the thread is
* discarded.
*/
kern_return_t
thread_set_mach_voucher(
thread_t thread,
ipc_voucher_t voucher)
{
ipc_voucher_t old_voucher;
ledger_t bankledger = NULL;
struct thread_group *banktg = NULL;
uint32_t persona_id = 0;
if (THREAD_NULL == thread) {
return KERN_INVALID_ARGUMENT;
}
bank_get_bank_ledger_thread_group_and_persona(voucher, &bankledger, &banktg, &persona_id);
thread_mtx_lock(thread);
/*
* Once the thread is started, we will look at `ith_voucher` without
* holding any lock.
*
* Setting the voucher hence can only be done by current_thread() or
* before it started. "started" flips under the thread mutex and must be
* tested under it too.
*/
if (thread != current_thread() && thread->started) {
thread_mtx_unlock(thread);
return KERN_INVALID_ARGUMENT;
}
ipc_voucher_reference(voucher);
old_voucher = thread->ith_voucher;
thread->ith_voucher = voucher;
thread->ith_voucher_name = MACH_PORT_NULL;
thread_mtx_unlock(thread);
bank_swap_thread_bank_ledger(thread, bankledger);
#if CONFIG_THREAD_GROUPS
thread_group_set_bank(thread, banktg);
#endif /* CONFIG_THREAD_GROUPS */
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
MACHDBG_CODE(DBG_MACH_IPC, MACH_THREAD_SET_VOUCHER) | DBG_FUNC_NONE,
(uintptr_t)thread_tid(thread),
(uintptr_t)MACH_PORT_NULL,
VM_KERNEL_ADDRPERM((uintptr_t)voucher),
persona_id, 0);
ipc_voucher_release(old_voucher);
return KERN_SUCCESS;
}
/*
* thread_swap_mach_voucher - swap a voucher reference for the specified thread voucher
*
* Conditions: callers holds a reference on the new and presumed old voucher(s).
* nothing locked.
*
* This function is no longer supported.
*/
kern_return_t
thread_swap_mach_voucher(
__unused thread_t thread,
__unused ipc_voucher_t new_voucher,
ipc_voucher_t *in_out_old_voucher)
{
/*
* Currently this function is only called from a MIG generated
* routine which doesn't release the reference on the voucher
* addressed by in_out_old_voucher. To avoid leaking this reference,
* a call to release it has been added here.
*/
ipc_voucher_release(*in_out_old_voucher);
OS_ANALYZER_SUPPRESS("81787115") return KERN_NOT_SUPPORTED;
}
/*
* thread_get_current_voucher_origin_pid - get the pid of the originator of the current voucher.
*/
kern_return_t
thread_get_current_voucher_origin_pid(
int32_t *pid)
{
return thread_get_voucher_origin_pid(current_thread(), pid);
}
/*
* thread_get_current_voucher_origin_pid - get the pid of the originator of the current voucher.
*/
kern_return_t
thread_get_voucher_origin_pid(thread_t thread, int32_t *pid)
{
uint32_t buf_size = sizeof(*pid);
return mach_voucher_attr_command(thread->ith_voucher,
MACH_VOUCHER_ATTR_KEY_BANK,
BANK_ORIGINATOR_PID,
NULL,
0,
(mach_voucher_attr_content_t)pid,
&buf_size);
}
/*
* thread_get_current_voucher_proximate_pid - get the pid of the proximate process of the current voucher.
*/
kern_return_t
thread_get_voucher_origin_proximate_pid(thread_t thread, int32_t *origin_pid, int32_t *proximate_pid)
{
int32_t origin_proximate_pids[2] = { };
uint32_t buf_size = sizeof(origin_proximate_pids);
kern_return_t kr = mach_voucher_attr_command(thread->ith_voucher,
MACH_VOUCHER_ATTR_KEY_BANK,
BANK_ORIGINATOR_PROXIMATE_PID,
NULL,
0,
(mach_voucher_attr_content_t)origin_proximate_pids,
&buf_size);
if (kr == KERN_SUCCESS) {
*origin_pid = origin_proximate_pids[0];
*proximate_pid = origin_proximate_pids[1];
}
return kr;
}
#if CONFIG_THREAD_GROUPS
/*
* Returns the current thread's voucher-carried thread group
*
* Reference is borrowed from this being the current voucher, so it does NOT
* return a reference to the group.
*/
struct thread_group *
thread_get_current_voucher_thread_group(thread_t thread)
{
assert(thread == current_thread());
if (thread->ith_voucher == NULL) {
return NULL;
}
ledger_t bankledger = NULL;
struct thread_group *banktg = NULL;
bank_get_bank_ledger_thread_group_and_persona(thread->ith_voucher, &bankledger, &banktg, NULL);
return banktg;
}
#endif /* CONFIG_THREAD_GROUPS */
#if CONFIG_COALITIONS
uint64_t
thread_get_current_voucher_resource_coalition_id(thread_t thread)
{
uint64_t id = 0;
assert(thread == current_thread());
if (thread->ith_voucher != NULL) {
id = bank_get_bank_ledger_resource_coalition_id(thread->ith_voucher);
}
return id;
}
#endif /* CONFIG_COALITIONS */
extern struct workqueue *
proc_get_wqptr(void *proc);
static bool
task_supports_cooperative_workqueue(task_t task)
{
void *bsd_info = get_bsdtask_info(task);
assert(task == current_task());
if (bsd_info == NULL) {
return false;
}
uint64_t wq_quantum_expiry_offset = get_wq_quantum_offset_from_proc(bsd_info);
/* userspace may not yet have called workq_open yet */
struct workqueue *wq = proc_get_wqptr(bsd_info);
return (wq != NULL) && (wq_quantum_expiry_offset != 0);
}
/* Not safe to call from scheduler paths - should only be called on self */
bool
thread_supports_cooperative_workqueue(thread_t thread)
{
struct uthread *uth = get_bsdthread_info(thread);
task_t task = get_threadtask(thread);
assert(thread == current_thread());
return task_supports_cooperative_workqueue(task) &&
bsdthread_part_of_cooperative_workqueue(uth);
}
static inline bool
thread_has_armed_workqueue_quantum(thread_t thread)
{
return thread->workq_quantum_deadline != 0;
}
/*
* The workq quantum is a lazy timer that is evaluated at 2 specific times in
* the scheduler:
*
* - context switch time
* - scheduler quantum expiry time.
*
* We're currently expressing the workq quantum with a 0.5 scale factor of the
* scheduler quantum. It is possible that if the workq quantum is rearmed
* shortly after the scheduler quantum begins, we could have a large delay
* between when the workq quantum next expires and when it actually is noticed.
*
* A potential future improvement for the wq quantum expiry logic is to compare
* it to the next actual scheduler quantum deadline and expire it if it is
* within a certain leeway.
*/
static inline uint64_t
thread_workq_quantum_size(thread_t thread)
{
return (uint64_t) (SCHED(initial_quantum_size)(thread) / 2);
}
/*
* Always called by thread on itself - either at AST boundary after processing
* an existing quantum expiry, or when a new quantum is armed before the thread
* goes out to userspace to handle a thread request
*/
void
thread_arm_workqueue_quantum(thread_t thread)
{
/*
* If the task is not opted into wq quantum notification, or if the thread
* is not part of the cooperative workqueue, don't even bother with tracking
* the quantum or calculating expiry
*/
if (!thread_supports_cooperative_workqueue(thread)) {
assert(thread->workq_quantum_deadline == 0);
return;
}
assert(current_thread() == thread);
assert(thread_get_tag(thread) & THREAD_TAG_WORKQUEUE);
uint64_t current_runtime = thread_get_runtime_self();
uint64_t deadline = thread_workq_quantum_size(thread) + current_runtime;
/*
* The update of a workqueue quantum should always be followed by the update
* of the AST - see explanation in kern/thread.h for synchronization of this
* field
*/
thread->workq_quantum_deadline = deadline;
/* We're arming a new quantum, clear any previous expiry notification */
act_clear_astkevent(thread, AST_KEVENT_WORKQ_QUANTUM_EXPIRED);
WQ_TRACE(TRACE_wq_quantum_arm, current_runtime, deadline, 0, 0);
WORKQ_QUANTUM_HISTORY_WRITE_ENTRY(thread, thread->workq_quantum_deadline, true);
}
/* Called by a thread on itself when it is about to park */
void
thread_disarm_workqueue_quantum(thread_t thread)
{
/* The update of a workqueue quantum should always be followed by the update
* of the AST - see explanation in kern/thread.h for synchronization of this
* field */
thread->workq_quantum_deadline = 0;
act_clear_astkevent(thread, AST_KEVENT_WORKQ_QUANTUM_EXPIRED);
WQ_TRACE(TRACE_wq_quantum_disarm, 0, 0, 0, 0);
WORKQ_QUANTUM_HISTORY_WRITE_ENTRY(thread, thread->workq_quantum_deadline, false);
}
/* This is called at context switch time on a thread that may not be self,
* and at AST time
*/
bool
thread_has_expired_workqueue_quantum(thread_t thread, bool should_trace)
{
if (!thread_has_armed_workqueue_quantum(thread)) {
return false;
}
/* We do not do a thread_get_runtime_self() here since this function is
* called from context switch time or during scheduler quantum expiry and
* therefore, we may not be evaluating it on the current thread/self.
*
* In addition, the timers on the thread have just been updated recently so
* we don't need to update them again.
*/
uint64_t runtime = recount_thread_time_mach(thread);
bool expired = runtime > thread->workq_quantum_deadline;
if (expired && should_trace) {
WQ_TRACE(TRACE_wq_quantum_expired, runtime, thread->workq_quantum_deadline, 0, 0);
}
return expired;
}
/*
* Called on a thread that is being context switched out or during quantum
* expiry on self. Only called from scheduler paths.
*/
void
thread_evaluate_workqueue_quantum_expiry(thread_t thread)
{
if (thread_has_expired_workqueue_quantum(thread, true)) {
act_set_astkevent(thread, AST_KEVENT_WORKQ_QUANTUM_EXPIRED);
}
}
boolean_t
thread_has_thread_name(thread_t th)
{
if (th) {
return bsd_hasthreadname(get_bsdthread_info(th));
}
/*
* This is an odd case; clients may set the thread name based on the lack of
* a name, but in this context there is no uthread to attach the name to.
*/
return FALSE;
}
void
thread_set_thread_name(thread_t th, const char* name)
{
if (th && name) {
bsd_setthreadname(get_bsdthread_info(th), thread_tid(th), name);
}
}
void
thread_get_thread_name(thread_t th, char* name)
{
if (!name) {
return;
}
if (th) {
bsd_getthreadname(get_bsdthread_info(th), name);
} else {
name[0] = '\0';
}
}
processor_t
thread_get_runq(thread_t thread)
{
thread_lock_assert(thread, LCK_ASSERT_OWNED);
processor_t runq = thread->__runq.runq;
os_atomic_thread_fence(acquire);
return runq;
}
processor_t
thread_get_runq_locked(thread_t thread)
{
thread_lock_assert(thread, LCK_ASSERT_OWNED);
processor_t runq = thread->__runq.runq;
if (runq != PROCESSOR_NULL) {
pset_assert_locked(runq->processor_set);
}
return runq;
}
void
thread_set_runq_locked(thread_t thread, processor_t new_runq)
{
thread_lock_assert(thread, LCK_ASSERT_OWNED);
pset_assert_locked(new_runq->processor_set);
thread_assert_runq_null(thread);
thread->__runq.runq = new_runq;
}
void
thread_clear_runq(thread_t thread)
{
thread_assert_runq_nonnull(thread);
os_atomic_thread_fence(release);
thread->__runq.runq = PROCESSOR_NULL;
}
void
thread_clear_runq_locked(thread_t thread)
{
thread_lock_assert(thread, LCK_ASSERT_OWNED);
thread_assert_runq_nonnull(thread);
thread->__runq.runq = PROCESSOR_NULL;
}
void
thread_assert_runq_null(__assert_only thread_t thread)
{
assert(thread->__runq.runq == PROCESSOR_NULL);
}
void
thread_assert_runq_nonnull(thread_t thread)
{
pset_assert_locked(thread->__runq.runq->processor_set);
assert(thread->__runq.runq != PROCESSOR_NULL);
}
void
thread_set_honor_qlimit(thread_t thread)
{
thread->options |= TH_OPT_HONOR_QLIMIT;
}
void
thread_clear_honor_qlimit(thread_t thread)
{
thread->options &= (~TH_OPT_HONOR_QLIMIT);
}
/*
* thread_enable_send_importance - set/clear the SEND_IMPORTANCE thread option bit.
*/
void
thread_enable_send_importance(thread_t thread, boolean_t enable)
{
if (enable == TRUE) {
thread->options |= TH_OPT_SEND_IMPORTANCE;
} else {
thread->options &= ~TH_OPT_SEND_IMPORTANCE;
}
}
kern_return_t
thread_get_ipc_propagate_attr(thread_t thread, struct thread_attr_for_ipc_propagation *attr)
{
int iotier;
int qos;
if (thread == NULL || attr == NULL) {
return KERN_INVALID_ARGUMENT;
}
iotier = proc_get_effective_thread_policy(thread, TASK_POLICY_IO);
qos = proc_get_effective_thread_policy(thread, TASK_POLICY_QOS);
if (!qos) {
qos = thread_user_promotion_qos_for_pri(thread->base_pri);
}
attr->tafip_iotier = iotier;
attr->tafip_qos = qos;
return KERN_SUCCESS;
}
/*
* thread_set_allocation_name - .
*/
kern_allocation_name_t
thread_set_allocation_name(kern_allocation_name_t new_name)
{
kern_allocation_name_t ret;
thread_kernel_state_t kstate = thread_get_kernel_state(current_thread());
ret = kstate->allocation_name;
// fifo
if (!new_name || !kstate->allocation_name) {
kstate->allocation_name = new_name;
}
return ret;
}
void *
thread_iokit_tls_get(uint32_t index)
{
assert(index < THREAD_SAVE_IOKIT_TLS_COUNT);
return current_thread()->saved.iokit.tls[index];
}
void
thread_iokit_tls_set(uint32_t index, void * data)
{
assert(index < THREAD_SAVE_IOKIT_TLS_COUNT);
current_thread()->saved.iokit.tls[index] = data;
}
uint64_t
thread_get_last_wait_duration(thread_t thread)
{
return thread->last_made_runnable_time - thread->last_run_time;
}
integer_t
thread_kern_get_pri(thread_t thr)
{
return thr->base_pri;
}
void
thread_kern_set_pri(thread_t thr, integer_t pri)
{
sched_set_kernel_thread_priority(thr, pri);
}
integer_t
thread_kern_get_kernel_maxpri(void)
{
return MAXPRI_KERNEL;
}
/*
* thread_port_with_flavor_no_senders
*
* Called whenever the Mach port system detects no-senders on
* the thread inspect or read port. These ports are allocated lazily and
* should be deallocated here when there are no senders remaining.
*/
static void
thread_port_with_flavor_no_senders(
ipc_port_t port,
mach_port_mscount_t mscount __unused)
{
thread_ro_t tro;
thread_t thread;
mach_thread_flavor_t flavor;
ipc_kobject_type_t kotype;
ip_mq_lock(port);
if (port->ip_srights > 0) {
ip_mq_unlock(port);
return;
}
kotype = ip_kotype(port);
assert((IKOT_THREAD_READ == kotype) || (IKOT_THREAD_INSPECT == kotype));
thread = ipc_kobject_get_locked(port, kotype);
if (thread != THREAD_NULL) {
thread_reference(thread);
}
ip_mq_unlock(port);
if (thread == THREAD_NULL) {
/* The thread is exiting or disabled; it will eventually deallocate the port */
return;
}
if (kotype == IKOT_THREAD_READ) {
flavor = THREAD_FLAVOR_READ;
} else {
flavor = THREAD_FLAVOR_INSPECT;
}
thread_mtx_lock(thread);
ip_mq_lock(port);
/*
* If the port is no longer active, then ipc_thread_terminate() ran
* and destroyed the kobject already. Just deallocate the task
* ref we took and go away.
*
* It is also possible that several nsrequests are in flight,
* only one shall NULL-out the port entry, and this is the one
* that gets to dealloc the port.
*
* Check for a stale no-senders notification. A call to any function
* that vends out send rights to this port could resurrect it between
* this notification being generated and actually being handled here.
*/
tro = get_thread_ro(thread);
if (!ip_active(port) ||
tro->tro_ports[flavor] != port ||
port->ip_srights > 0) {
ip_mq_unlock(port);
thread_mtx_unlock(thread);
thread_deallocate(thread);
return;
}
assert(tro->tro_ports[flavor] == port);
zalloc_ro_clear_field(ZONE_ID_THREAD_RO, tro, tro_ports[flavor]);
thread_mtx_unlock(thread);
ipc_kobject_dealloc_port_and_unlock(port, 0, kotype);
thread_deallocate(thread);
}
/*
* The 'thread_region_page_shift' is used by footprint
* to specify the page size that it will use to
* accomplish its accounting work on the task being
* inspected. Since footprint uses a thread for each
* task that it works on, we need to keep the page_shift
* on a per-thread basis.
*/
int
thread_self_region_page_shift(void)
{
/*
* Return the page shift that this thread
* would like to use for its accounting work.
*/
return current_thread()->thread_region_page_shift;
}
void
thread_self_region_page_shift_set(
int pgshift)
{
/*
* Set the page shift that this thread
* would like to use for its accounting work
* when dealing with a task.
*/
current_thread()->thread_region_page_shift = pgshift;
}
__startup_func
static void
ctid_table_init(void)
{
/*
* Pretend the early boot setup didn't exist,
* and pick a mangling nonce.
*/
*compact_id_resolve(&ctid_table, 0) = THREAD_NULL;
ctid_nonce = (uint32_t)early_random() & CTID_MASK;
}
/*
* This maps the [0, CTID_MAX_THREAD_NUMBER] range
* to [1, CTID_MAX_THREAD_NUMBER + 1 == CTID_MASK]
* so that in mangled form, '0' is an invalid CTID.
*/
static ctid_t
ctid_mangle(compact_id_t cid)
{
return (cid == ctid_nonce ? CTID_MASK : cid) ^ ctid_nonce;
}
static compact_id_t
ctid_unmangle(ctid_t ctid)
{
ctid ^= ctid_nonce;
return ctid == CTID_MASK ? ctid_nonce : ctid;
}
void
ctid_table_add(thread_t thread)
{
compact_id_t cid;
cid = compact_id_get(&ctid_table, CTID_MAX_THREAD_NUMBER, thread);
thread->ctid = ctid_mangle(cid);
}
void
ctid_table_remove(thread_t thread)
{
__assert_only thread_t value;
value = compact_id_put(&ctid_table, ctid_unmangle(thread->ctid));
assert3p(value, ==, thread);
thread->ctid = 0;
}
thread_t
ctid_get_thread_unsafe(ctid_t ctid)
{
if (ctid) {
return *compact_id_resolve(&ctid_table, ctid_unmangle(ctid));
}
return THREAD_NULL;
}
thread_t
ctid_get_thread(ctid_t ctid)
{
thread_t thread = THREAD_NULL;
if (ctid) {
thread = *compact_id_resolve(&ctid_table, ctid_unmangle(ctid));
assert(thread && thread->ctid == ctid);
}
return thread;
}
ctid_t
thread_get_ctid(thread_t thread)
{
return thread->ctid;
}
/*
* Adjust code signature dependent thread state.
*
* Called to allow code signature dependent adjustments to the thread
* state. Note that this is usually called twice for the main thread:
* Once at thread creation by thread_create, when the signature is
* potentially not attached yet (which is usually the case for the
* first/main thread of a task), and once after the task's signature
* has actually been attached.
*
*/
kern_return_t
thread_process_signature(thread_t thread, task_t task)
{
return machine_thread_process_signature(thread, task);
}
#if CONFIG_SPTM
void
thread_associate_txm_thread_stack(uintptr_t thread_stack)
{
thread_t self = current_thread();
if (self->txm_thread_stack != 0) {
panic("attempted multiple TXM thread associations: %lu | %lu",
self->txm_thread_stack, thread_stack);
}
self->txm_thread_stack = thread_stack;
}
void
thread_disassociate_txm_thread_stack(uintptr_t thread_stack)
{
thread_t self = current_thread();
if (self->txm_thread_stack == 0) {
panic("attempted to disassociate non-existent TXM thread");
} else if (self->txm_thread_stack != thread_stack) {
panic("invalid disassociation for TXM thread: %lu | %lu",
self->txm_thread_stack, thread_stack);
}
self->txm_thread_stack = 0;
}
uintptr_t
thread_get_txm_thread_stack(void)
{
return current_thread()->txm_thread_stack;
}
#endif
#if CONFIG_DTRACE
uint32_t
dtrace_get_thread_predcache(thread_t thread)
{
if (thread != THREAD_NULL) {
return thread->t_dtrace_predcache;
} else {
return 0;
}
}
int64_t
dtrace_get_thread_vtime(thread_t thread)
{
if (thread != THREAD_NULL) {
return thread->t_dtrace_vtime;
} else {
return 0;
}
}
int
dtrace_get_thread_last_cpu_id(thread_t thread)
{
if ((thread != THREAD_NULL) && (thread->last_processor != PROCESSOR_NULL)) {
return thread->last_processor->cpu_id;
} else {
return -1;
}
}
int64_t
dtrace_get_thread_tracing(thread_t thread)
{
if (thread != THREAD_NULL) {
return thread->t_dtrace_tracing;
} else {
return 0;
}
}
uint16_t
dtrace_get_thread_inprobe(thread_t thread)
{
if (thread != THREAD_NULL) {
return thread->t_dtrace_inprobe;
} else {
return 0;
}
}
vm_offset_t
thread_get_kernel_stack(thread_t thread)
{
if (thread != THREAD_NULL) {
return thread->kernel_stack;
} else {
return 0;
}
}
#if KASAN
struct kasan_thread_data *
kasan_get_thread_data(thread_t thread)
{
return &thread->kasan_data;
}
#endif
#if CONFIG_KCOV
kcov_thread_data_t *
kcov_get_thread_data(thread_t thread)
{
return &thread->kcov_data;
}
#endif
#if CONFIG_STKSZ
/*
* Returns base of a thread's kernel stack.
*
* Coverage sanitizer instruments every function including those that participates in stack handoff between threads.
* There is a window in which CPU still holds old values but stack has been handed over to anoher thread already.
* In this window kernel_stack is 0 but CPU still uses the original stack (until contex switch occurs). The original
* kernel_stack value is preserved in ksancov_stack during this window.
*/
vm_offset_t
kcov_stksz_get_thread_stkbase(thread_t thread)
{
if (thread != THREAD_NULL) {
kcov_thread_data_t *data = kcov_get_thread_data(thread);
if (data->ktd_stksz.kst_stack) {
return data->ktd_stksz.kst_stack;
} else {
return thread->kernel_stack;
}
} else {
return 0;
}
}
vm_offset_t
kcov_stksz_get_thread_stksize(thread_t thread)
{
if (thread != THREAD_NULL) {
return kernel_stack_size;
} else {
return 0;
}
}
void
kcov_stksz_set_thread_stack(thread_t thread, vm_offset_t stack)
{
kcov_thread_data_t *data = kcov_get_thread_data(thread);
data->ktd_stksz.kst_stack = stack;
}
#endif /* CONFIG_STKSZ */
int64_t
dtrace_calc_thread_recent_vtime(thread_t thread)
{
if (thread == THREAD_NULL) {
return 0;
}
struct recount_usage usage = { 0 };
recount_current_thread_usage(&usage);
return (int64_t)(recount_usage_time_mach(&usage));
}
void
dtrace_set_thread_predcache(thread_t thread, uint32_t predcache)
{
if (thread != THREAD_NULL) {
thread->t_dtrace_predcache = predcache;
}
}
void
dtrace_set_thread_vtime(thread_t thread, int64_t vtime)
{
if (thread != THREAD_NULL) {
thread->t_dtrace_vtime = vtime;
}
}
void
dtrace_set_thread_tracing(thread_t thread, int64_t accum)
{
if (thread != THREAD_NULL) {
thread->t_dtrace_tracing = accum;
}
}
void
dtrace_set_thread_inprobe(thread_t thread, uint16_t inprobe)
{
if (thread != THREAD_NULL) {
thread->t_dtrace_inprobe = inprobe;
}
}
void
dtrace_thread_bootstrap(void)
{
task_t task = current_task();
if (task->thread_count == 1) {
thread_t thread = current_thread();
if (thread->t_dtrace_flags & TH_DTRACE_EXECSUCCESS) {
thread->t_dtrace_flags &= ~TH_DTRACE_EXECSUCCESS;
DTRACE_PROC(exec__success);
KDBG(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXEC),
task_pid(task));
}
DTRACE_PROC(start);
}
DTRACE_PROC(lwp__start);
}
void
dtrace_thread_didexec(thread_t thread)
{
thread->t_dtrace_flags |= TH_DTRACE_EXECSUCCESS;
}
#endif /* CONFIG_DTRACE */