#include "internal.h"
#if HAVE_MACH
#include "protocol.h"
#endif
#if (!HAVE_PTHREAD_WORKQUEUES || DISPATCH_DEBUG) && \
!defined(DISPATCH_ENABLE_THREAD_POOL)
#define DISPATCH_ENABLE_THREAD_POOL 1
#endif
#if DISPATCH_ENABLE_PTHREAD_ROOT_QUEUES || DISPATCH_ENABLE_THREAD_POOL
#define DISPATCH_USE_PTHREAD_POOL 1
#endif
#if HAVE_PTHREAD_WORKQUEUES && !HAVE_PTHREAD_WORKQUEUE_SETDISPATCH_NP && \
!defined(DISPATCH_USE_LEGACY_WORKQUEUE_FALLBACK)
#define DISPATCH_USE_LEGACY_WORKQUEUE_FALLBACK 1
#endif
#if HAVE_PTHREAD_WORKQUEUES && DISPATCH_USE_PTHREAD_POOL && \
!DISPATCH_USE_LEGACY_WORKQUEUE_FALLBACK
#define pthread_workqueue_t void*
#endif
static void _dispatch_cache_cleanup(void *value);
static void _dispatch_async_f_redirect(dispatch_queue_t dq,
dispatch_continuation_t dc);
static void _dispatch_queue_cleanup(void *ctxt);
static inline void _dispatch_queue_wakeup_global2(dispatch_queue_t dq,
unsigned int n);
static inline void _dispatch_queue_wakeup_global(dispatch_queue_t dq);
static inline _dispatch_thread_semaphore_t
_dispatch_queue_drain_one_barrier_sync(dispatch_queue_t dq);
#if HAVE_PTHREAD_WORKQUEUES
static void _dispatch_worker_thread3(void *context);
#if HAVE_PTHREAD_WORKQUEUE_SETDISPATCH_NP
static void _dispatch_worker_thread2(int priority, int options, void *context);
#endif
#endif
#if DISPATCH_USE_PTHREAD_POOL
static void *_dispatch_worker_thread(void *context);
static int _dispatch_pthread_sigmask(int how, sigset_t *set, sigset_t *oset);
#endif
#if DISPATCH_COCOA_COMPAT
static dispatch_once_t _dispatch_main_q_port_pred;
static dispatch_queue_t _dispatch_main_queue_wakeup(void);
unsigned long _dispatch_runloop_queue_wakeup(dispatch_queue_t dq);
static void _dispatch_runloop_queue_port_init(void *ctxt);
static void _dispatch_runloop_queue_port_dispose(dispatch_queue_t dq);
#endif
#pragma mark -
#pragma mark dispatch_root_queue
#if DISPATCH_ENABLE_THREAD_POOL
static struct dispatch_semaphore_s _dispatch_thread_mediator[] = {
[DISPATCH_ROOT_QUEUE_IDX_LOW_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(semaphore),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
},
[DISPATCH_ROOT_QUEUE_IDX_LOW_OVERCOMMIT_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(semaphore),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
},
[DISPATCH_ROOT_QUEUE_IDX_DEFAULT_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(semaphore),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
},
[DISPATCH_ROOT_QUEUE_IDX_DEFAULT_OVERCOMMIT_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(semaphore),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
},
[DISPATCH_ROOT_QUEUE_IDX_HIGH_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(semaphore),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
},
[DISPATCH_ROOT_QUEUE_IDX_HIGH_OVERCOMMIT_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(semaphore),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
},
[DISPATCH_ROOT_QUEUE_IDX_BACKGROUND_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(semaphore),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
},
[DISPATCH_ROOT_QUEUE_IDX_BACKGROUND_OVERCOMMIT_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(semaphore),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
},
};
#endif
#define MAX_PTHREAD_COUNT 255
struct dispatch_root_queue_context_s {
union {
struct {
unsigned int volatile dgq_pending;
#if HAVE_PTHREAD_WORKQUEUES
int dgq_wq_priority, dgq_wq_options;
#if DISPATCH_USE_LEGACY_WORKQUEUE_FALLBACK || DISPATCH_USE_PTHREAD_POOL
pthread_workqueue_t dgq_kworkqueue;
#endif
#endif // HAVE_PTHREAD_WORKQUEUES
#if DISPATCH_USE_PTHREAD_POOL
void *dgq_ctxt;
dispatch_semaphore_t dgq_thread_mediator;
uint32_t volatile dgq_thread_pool_size;
#endif
};
char _dgq_pad[DISPATCH_CACHELINE_SIZE];
};
};
typedef struct dispatch_root_queue_context_s *dispatch_root_queue_context_t;
DISPATCH_CACHELINE_ALIGN
static struct dispatch_root_queue_context_s _dispatch_root_queue_contexts[] = {
[DISPATCH_ROOT_QUEUE_IDX_LOW_PRIORITY] = {{{
#if HAVE_PTHREAD_WORKQUEUES
.dgq_wq_priority = WORKQ_LOW_PRIOQUEUE,
.dgq_wq_options = 0,
#endif
#if DISPATCH_ENABLE_THREAD_POOL
.dgq_thread_mediator = &_dispatch_thread_mediator[
DISPATCH_ROOT_QUEUE_IDX_LOW_PRIORITY],
#endif
}}},
[DISPATCH_ROOT_QUEUE_IDX_LOW_OVERCOMMIT_PRIORITY] = {{{
#if HAVE_PTHREAD_WORKQUEUES
.dgq_wq_priority = WORKQ_LOW_PRIOQUEUE,
.dgq_wq_options = WORKQ_ADDTHREADS_OPTION_OVERCOMMIT,
#endif
#if DISPATCH_ENABLE_THREAD_POOL
.dgq_thread_mediator = &_dispatch_thread_mediator[
DISPATCH_ROOT_QUEUE_IDX_LOW_OVERCOMMIT_PRIORITY],
#endif
}}},
[DISPATCH_ROOT_QUEUE_IDX_DEFAULT_PRIORITY] = {{{
#if HAVE_PTHREAD_WORKQUEUES
.dgq_wq_priority = WORKQ_DEFAULT_PRIOQUEUE,
.dgq_wq_options = 0,
#endif
#if DISPATCH_ENABLE_THREAD_POOL
.dgq_thread_mediator = &_dispatch_thread_mediator[
DISPATCH_ROOT_QUEUE_IDX_DEFAULT_PRIORITY],
#endif
}}},
[DISPATCH_ROOT_QUEUE_IDX_DEFAULT_OVERCOMMIT_PRIORITY] = {{{
#if HAVE_PTHREAD_WORKQUEUES
.dgq_wq_priority = WORKQ_DEFAULT_PRIOQUEUE,
.dgq_wq_options = WORKQ_ADDTHREADS_OPTION_OVERCOMMIT,
#endif
#if DISPATCH_ENABLE_THREAD_POOL
.dgq_thread_mediator = &_dispatch_thread_mediator[
DISPATCH_ROOT_QUEUE_IDX_DEFAULT_OVERCOMMIT_PRIORITY],
#endif
}}},
[DISPATCH_ROOT_QUEUE_IDX_HIGH_PRIORITY] = {{{
#if HAVE_PTHREAD_WORKQUEUES
.dgq_wq_priority = WORKQ_HIGH_PRIOQUEUE,
.dgq_wq_options = 0,
#endif
#if DISPATCH_ENABLE_THREAD_POOL
.dgq_thread_mediator = &_dispatch_thread_mediator[
DISPATCH_ROOT_QUEUE_IDX_HIGH_PRIORITY],
#endif
}}},
[DISPATCH_ROOT_QUEUE_IDX_HIGH_OVERCOMMIT_PRIORITY] = {{{
#if HAVE_PTHREAD_WORKQUEUES
.dgq_wq_priority = WORKQ_HIGH_PRIOQUEUE,
.dgq_wq_options = WORKQ_ADDTHREADS_OPTION_OVERCOMMIT,
#endif
#if DISPATCH_ENABLE_THREAD_POOL
.dgq_thread_mediator = &_dispatch_thread_mediator[
DISPATCH_ROOT_QUEUE_IDX_HIGH_OVERCOMMIT_PRIORITY],
#endif
}}},
[DISPATCH_ROOT_QUEUE_IDX_BACKGROUND_PRIORITY] = {{{
#if HAVE_PTHREAD_WORKQUEUES
.dgq_wq_priority = WORKQ_BG_PRIOQUEUE,
.dgq_wq_options = 0,
#endif
#if DISPATCH_ENABLE_THREAD_POOL
.dgq_thread_mediator = &_dispatch_thread_mediator[
DISPATCH_ROOT_QUEUE_IDX_BACKGROUND_PRIORITY],
#endif
}}},
[DISPATCH_ROOT_QUEUE_IDX_BACKGROUND_OVERCOMMIT_PRIORITY] = {{{
#if HAVE_PTHREAD_WORKQUEUES
.dgq_wq_priority = WORKQ_BG_PRIOQUEUE,
.dgq_wq_options = WORKQ_ADDTHREADS_OPTION_OVERCOMMIT,
#endif
#if DISPATCH_ENABLE_THREAD_POOL
.dgq_thread_mediator = &_dispatch_thread_mediator[
DISPATCH_ROOT_QUEUE_IDX_BACKGROUND_OVERCOMMIT_PRIORITY],
#endif
}}},
};
DISPATCH_CACHELINE_ALIGN
struct dispatch_queue_s _dispatch_root_queues[] = {
[DISPATCH_ROOT_QUEUE_IDX_LOW_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(queue_root),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_suspend_cnt = DISPATCH_OBJECT_SUSPEND_LOCK,
.do_ctxt = &_dispatch_root_queue_contexts[
DISPATCH_ROOT_QUEUE_IDX_LOW_PRIORITY],
.dq_label = "com.apple.root.low-priority",
.dq_running = 2,
.dq_width = UINT32_MAX,
.dq_serialnum = 4,
},
[DISPATCH_ROOT_QUEUE_IDX_LOW_OVERCOMMIT_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(queue_root),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_suspend_cnt = DISPATCH_OBJECT_SUSPEND_LOCK,
.do_ctxt = &_dispatch_root_queue_contexts[
DISPATCH_ROOT_QUEUE_IDX_LOW_OVERCOMMIT_PRIORITY],
.dq_label = "com.apple.root.low-overcommit-priority",
.dq_running = 2,
.dq_width = UINT32_MAX,
.dq_serialnum = 5,
},
[DISPATCH_ROOT_QUEUE_IDX_DEFAULT_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(queue_root),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_suspend_cnt = DISPATCH_OBJECT_SUSPEND_LOCK,
.do_ctxt = &_dispatch_root_queue_contexts[
DISPATCH_ROOT_QUEUE_IDX_DEFAULT_PRIORITY],
.dq_label = "com.apple.root.default-priority",
.dq_running = 2,
.dq_width = UINT32_MAX,
.dq_serialnum = 6,
},
[DISPATCH_ROOT_QUEUE_IDX_DEFAULT_OVERCOMMIT_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(queue_root),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_suspend_cnt = DISPATCH_OBJECT_SUSPEND_LOCK,
.do_ctxt = &_dispatch_root_queue_contexts[
DISPATCH_ROOT_QUEUE_IDX_DEFAULT_OVERCOMMIT_PRIORITY],
.dq_label = "com.apple.root.default-overcommit-priority",
.dq_running = 2,
.dq_width = UINT32_MAX,
.dq_serialnum = 7,
},
[DISPATCH_ROOT_QUEUE_IDX_HIGH_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(queue_root),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_suspend_cnt = DISPATCH_OBJECT_SUSPEND_LOCK,
.do_ctxt = &_dispatch_root_queue_contexts[
DISPATCH_ROOT_QUEUE_IDX_HIGH_PRIORITY],
.dq_label = "com.apple.root.high-priority",
.dq_running = 2,
.dq_width = UINT32_MAX,
.dq_serialnum = 8,
},
[DISPATCH_ROOT_QUEUE_IDX_HIGH_OVERCOMMIT_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(queue_root),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_suspend_cnt = DISPATCH_OBJECT_SUSPEND_LOCK,
.do_ctxt = &_dispatch_root_queue_contexts[
DISPATCH_ROOT_QUEUE_IDX_HIGH_OVERCOMMIT_PRIORITY],
.dq_label = "com.apple.root.high-overcommit-priority",
.dq_running = 2,
.dq_width = UINT32_MAX,
.dq_serialnum = 9,
},
[DISPATCH_ROOT_QUEUE_IDX_BACKGROUND_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(queue_root),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_suspend_cnt = DISPATCH_OBJECT_SUSPEND_LOCK,
.do_ctxt = &_dispatch_root_queue_contexts[
DISPATCH_ROOT_QUEUE_IDX_BACKGROUND_PRIORITY],
.dq_label = "com.apple.root.background-priority",
.dq_running = 2,
.dq_width = UINT32_MAX,
.dq_serialnum = 10,
},
[DISPATCH_ROOT_QUEUE_IDX_BACKGROUND_OVERCOMMIT_PRIORITY] = {
.do_vtable = DISPATCH_VTABLE(queue_root),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_suspend_cnt = DISPATCH_OBJECT_SUSPEND_LOCK,
.do_ctxt = &_dispatch_root_queue_contexts[
DISPATCH_ROOT_QUEUE_IDX_BACKGROUND_OVERCOMMIT_PRIORITY],
.dq_label = "com.apple.root.background-overcommit-priority",
.dq_running = 2,
.dq_width = UINT32_MAX,
.dq_serialnum = 11,
},
};
#if HAVE_PTHREAD_WORKQUEUES
static const dispatch_queue_t _dispatch_wq2root_queues[][2] = {
[WORKQ_LOW_PRIOQUEUE][0] = &_dispatch_root_queues[
DISPATCH_ROOT_QUEUE_IDX_LOW_PRIORITY],
[WORKQ_LOW_PRIOQUEUE][WORKQ_ADDTHREADS_OPTION_OVERCOMMIT] =
&_dispatch_root_queues[
DISPATCH_ROOT_QUEUE_IDX_LOW_OVERCOMMIT_PRIORITY],
[WORKQ_DEFAULT_PRIOQUEUE][0] = &_dispatch_root_queues[
DISPATCH_ROOT_QUEUE_IDX_DEFAULT_PRIORITY],
[WORKQ_DEFAULT_PRIOQUEUE][WORKQ_ADDTHREADS_OPTION_OVERCOMMIT] =
&_dispatch_root_queues[
DISPATCH_ROOT_QUEUE_IDX_DEFAULT_OVERCOMMIT_PRIORITY],
[WORKQ_HIGH_PRIOQUEUE][0] = &_dispatch_root_queues[
DISPATCH_ROOT_QUEUE_IDX_HIGH_PRIORITY],
[WORKQ_HIGH_PRIOQUEUE][WORKQ_ADDTHREADS_OPTION_OVERCOMMIT] =
&_dispatch_root_queues[
DISPATCH_ROOT_QUEUE_IDX_HIGH_OVERCOMMIT_PRIORITY],
[WORKQ_BG_PRIOQUEUE][0] = &_dispatch_root_queues[
DISPATCH_ROOT_QUEUE_IDX_BACKGROUND_PRIORITY],
[WORKQ_BG_PRIOQUEUE][WORKQ_ADDTHREADS_OPTION_OVERCOMMIT] =
&_dispatch_root_queues[
DISPATCH_ROOT_QUEUE_IDX_BACKGROUND_OVERCOMMIT_PRIORITY],
};
#endif // HAVE_PTHREAD_WORKQUEUES
#if DISPATCH_ENABLE_PTHREAD_ROOT_QUEUES
static struct dispatch_queue_s _dispatch_mgr_root_queue;
#else
#define _dispatch_mgr_root_queue \
_dispatch_root_queues[DISPATCH_ROOT_QUEUE_IDX_HIGH_OVERCOMMIT_PRIORITY]
#endif
DISPATCH_CACHELINE_ALIGN
struct dispatch_queue_s _dispatch_mgr_q = {
.do_vtable = DISPATCH_VTABLE(queue_mgr),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_suspend_cnt = DISPATCH_OBJECT_SUSPEND_LOCK,
.do_targetq = &_dispatch_mgr_root_queue,
.dq_label = "com.apple.libdispatch-manager",
.dq_width = 1,
.dq_is_thread_bound = 1,
.dq_serialnum = 2,
};
dispatch_queue_t
dispatch_get_global_queue(long priority, unsigned long flags)
{
if (flags & ~(unsigned long)DISPATCH_QUEUE_OVERCOMMIT) {
return NULL;
}
return _dispatch_get_root_queue(priority,
flags & DISPATCH_QUEUE_OVERCOMMIT);
}
DISPATCH_ALWAYS_INLINE
static inline dispatch_queue_t
_dispatch_get_current_queue(void)
{
return _dispatch_queue_get_current() ?: _dispatch_get_root_queue(0, true);
}
dispatch_queue_t
dispatch_get_current_queue(void)
{
return _dispatch_get_current_queue();
}
DISPATCH_ALWAYS_INLINE
static inline bool
_dispatch_queue_targets_queue(dispatch_queue_t dq1, dispatch_queue_t dq2)
{
while (dq1) {
if (dq1 == dq2) {
return true;
}
dq1 = dq1->do_targetq;
}
return false;
}
#define DISPATCH_ASSERT_QUEUE_MESSAGE "BUG in client of libdispatch: " \
"Assertion failed: Block was run on an unexpected queue"
DISPATCH_NOINLINE
static void
_dispatch_assert_queue_fail(dispatch_queue_t dq, bool expected)
{
char *msg;
asprintf(&msg, "%s\n%s queue: 0x%p[%s]", DISPATCH_ASSERT_QUEUE_MESSAGE,
expected ? "Expected" : "Unexpected", dq, dq->dq_label ?
dq->dq_label : "");
_dispatch_log("%s", msg);
_dispatch_set_crash_log_message(msg);
_dispatch_hardware_crash();
free(msg);
}
void
dispatch_assert_queue(dispatch_queue_t dq)
{
if (slowpath(!dq) || slowpath(!(dx_metatype(dq) == _DISPATCH_QUEUE_TYPE))) {
DISPATCH_CLIENT_CRASH("invalid queue passed to "
"dispatch_assert_queue()");
}
dispatch_queue_t cq = _dispatch_queue_get_current();
if (fastpath(cq) && fastpath(_dispatch_queue_targets_queue(cq, dq))) {
return;
}
_dispatch_assert_queue_fail(dq, true);
}
void
dispatch_assert_queue_not(dispatch_queue_t dq)
{
if (slowpath(!dq) || slowpath(!(dx_metatype(dq) == _DISPATCH_QUEUE_TYPE))) {
DISPATCH_CLIENT_CRASH("invalid queue passed to "
"dispatch_assert_queue_not()");
}
dispatch_queue_t cq = _dispatch_queue_get_current();
if (slowpath(cq) && slowpath(_dispatch_queue_targets_queue(cq, dq))) {
_dispatch_assert_queue_fail(dq, false);
}
}
#if DISPATCH_DEBUG && DISPATCH_ROOT_QUEUE_DEBUG
#define _dispatch_root_queue_debug(...) _dispatch_debug(__VA_ARGS__)
#define _dispatch_debug_root_queue(...) dispatch_debug_queue(__VA_ARGS__)
#else
#define _dispatch_root_queue_debug(...)
#define _dispatch_debug_root_queue(...)
#endif
#pragma mark -
#pragma mark dispatch_init
static void
_dispatch_hw_config_init(void)
{
_dispatch_hw_config.cc_max_active = _dispatch_get_activecpu();
_dispatch_hw_config.cc_max_logical = _dispatch_get_logicalcpu_max();
_dispatch_hw_config.cc_max_physical = _dispatch_get_physicalcpu_max();
}
static inline bool
_dispatch_root_queues_init_workq(void)
{
bool result = false;
#if HAVE_PTHREAD_WORKQUEUES
bool disable_wq = false;
#if DISPATCH_ENABLE_THREAD_POOL && DISPATCH_DEBUG
disable_wq = slowpath(getenv("LIBDISPATCH_DISABLE_KWQ"));
#endif
int r;
#if HAVE_PTHREAD_WORKQUEUE_SETDISPATCH_NP
if (!disable_wq) {
#if PTHREAD_WORKQUEUE_SPI_VERSION >= 20121218
pthread_workqueue_setdispatchoffset_np(
offsetof(struct dispatch_queue_s, dq_serialnum));
#endif
r = pthread_workqueue_setdispatch_np(_dispatch_worker_thread2);
#if !DISPATCH_USE_LEGACY_WORKQUEUE_FALLBACK
(void)dispatch_assume_zero(r);
#endif
result = !r;
}
#endif // HAVE_PTHREAD_WORKQUEUE_SETDISPATCH_NP
#if DISPATCH_USE_LEGACY_WORKQUEUE_FALLBACK || DISPATCH_USE_PTHREAD_POOL
if (!result) {
#if DISPATCH_USE_LEGACY_WORKQUEUE_FALLBACK
pthread_workqueue_attr_t pwq_attr;
if (!disable_wq) {
r = pthread_workqueue_attr_init_np(&pwq_attr);
(void)dispatch_assume_zero(r);
}
#endif
int i;
for (i = 0; i < DISPATCH_ROOT_QUEUE_COUNT; i++) {
pthread_workqueue_t pwq = NULL;
dispatch_root_queue_context_t qc;
qc = &_dispatch_root_queue_contexts[i];
#if DISPATCH_USE_LEGACY_WORKQUEUE_FALLBACK
if (!disable_wq
#if DISPATCH_NO_BG_PRIORITY
&& (qc->dgq_wq_priority != WORKQ_BG_PRIOQUEUE)
#endif
) {
r = pthread_workqueue_attr_setqueuepriority_np(&pwq_attr,
qc->dgq_wq_priority);
(void)dispatch_assume_zero(r);
r = pthread_workqueue_attr_setovercommit_np(&pwq_attr,
qc->dgq_wq_options &
WORKQ_ADDTHREADS_OPTION_OVERCOMMIT);
(void)dispatch_assume_zero(r);
r = pthread_workqueue_create_np(&pwq, &pwq_attr);
(void)dispatch_assume_zero(r);
result = result || dispatch_assume(pwq);
}
#endif // DISPATCH_USE_LEGACY_WORKQUEUE_FALLBACK
qc->dgq_kworkqueue = pwq ? pwq : (void*)(~0ul);
}
#if DISPATCH_USE_LEGACY_WORKQUEUE_FALLBACK
if (!disable_wq) {
r = pthread_workqueue_attr_destroy_np(&pwq_attr);
(void)dispatch_assume_zero(r);
}
#endif
}
#endif // DISPATCH_USE_LEGACY_WORKQUEUE_FALLBACK || DISPATCH_ENABLE_THREAD_POOL
#endif // HAVE_PTHREAD_WORKQUEUES
return result;
}
#if DISPATCH_USE_PTHREAD_POOL
static inline void
_dispatch_root_queue_init_pthread_pool(dispatch_root_queue_context_t qc,
bool overcommit)
{
qc->dgq_thread_pool_size = overcommit ? MAX_PTHREAD_COUNT :
_dispatch_hw_config.cc_max_active;
#if USE_MACH_SEM
kern_return_t kr = semaphore_create(mach_task_self(),
&qc->dgq_thread_mediator->dsema_port, SYNC_POLICY_LIFO, 0);
DISPATCH_VERIFY_MIG(kr);
(void)dispatch_assume_zero(kr);
(void)dispatch_assume(qc->dgq_thread_mediator->dsema_port);
#elif USE_POSIX_SEM
int ret = sem_init(&qc->dgq_thread_mediator->dsema_sem, 0, 0);
(void)dispatch_assume_zero(ret);
#endif
}
#endif // DISPATCH_USE_PTHREAD_POOL
static void
_dispatch_root_queues_init(void *context DISPATCH_UNUSED)
{
_dispatch_safe_fork = false;
if (!_dispatch_root_queues_init_workq()) {
#if DISPATCH_ENABLE_THREAD_POOL
int i;
for (i = 0; i < DISPATCH_ROOT_QUEUE_COUNT; i++) {
bool overcommit = true;
#if TARGET_OS_EMBEDDED
if (!(i & 1)) {
overcommit = false;
}
#endif
_dispatch_root_queue_init_pthread_pool(
&_dispatch_root_queue_contexts[i], overcommit);
}
#else
DISPATCH_CRASH("Root queue initialization failed");
#endif // DISPATCH_ENABLE_THREAD_POOL
}
}
#define countof(x) (sizeof(x) / sizeof(x[0]))
DISPATCH_EXPORT DISPATCH_NOTHROW
void
libdispatch_init(void)
{
dispatch_assert(DISPATCH_QUEUE_PRIORITY_COUNT == 4);
dispatch_assert(DISPATCH_ROOT_QUEUE_COUNT == 8);
dispatch_assert(DISPATCH_QUEUE_PRIORITY_LOW ==
-DISPATCH_QUEUE_PRIORITY_HIGH);
dispatch_assert(countof(_dispatch_root_queues) ==
DISPATCH_ROOT_QUEUE_COUNT);
dispatch_assert(countof(_dispatch_root_queue_contexts) ==
DISPATCH_ROOT_QUEUE_COUNT);
#if HAVE_PTHREAD_WORKQUEUES
dispatch_assert(sizeof(_dispatch_wq2root_queues) /
sizeof(_dispatch_wq2root_queues[0][0]) ==
DISPATCH_ROOT_QUEUE_COUNT);
#endif
#if DISPATCH_ENABLE_THREAD_POOL
dispatch_assert(countof(_dispatch_thread_mediator) ==
DISPATCH_ROOT_QUEUE_COUNT);
#endif
dispatch_assert(sizeof(struct dispatch_apply_s) <=
DISPATCH_CONTINUATION_SIZE);
dispatch_assert(sizeof(struct dispatch_queue_s) % DISPATCH_CACHELINE_SIZE
== 0);
dispatch_assert(sizeof(struct dispatch_root_queue_context_s) %
DISPATCH_CACHELINE_SIZE == 0);
_dispatch_thread_key_create(&dispatch_queue_key, _dispatch_queue_cleanup);
#if !DISPATCH_USE_OS_SEMAPHORE_CACHE
_dispatch_thread_key_create(&dispatch_sema4_key,
(void (*)(void *))_dispatch_thread_semaphore_dispose);
#endif
_dispatch_thread_key_create(&dispatch_cache_key, _dispatch_cache_cleanup);
_dispatch_thread_key_create(&dispatch_io_key, NULL);
_dispatch_thread_key_create(&dispatch_apply_key, NULL);
#if DISPATCH_PERF_MON
_dispatch_thread_key_create(&dispatch_bcounter_key, NULL);
#endif
#if DISPATCH_USE_RESOLVERS // rdar://problem/8541707
_dispatch_main_q.do_targetq = &_dispatch_root_queues[
DISPATCH_ROOT_QUEUE_IDX_DEFAULT_OVERCOMMIT_PRIORITY];
#endif
_dispatch_thread_setspecific(dispatch_queue_key, &_dispatch_main_q);
_dispatch_queue_set_bound_thread(&_dispatch_main_q);
#if DISPATCH_USE_PTHREAD_ATFORK
(void)dispatch_assume_zero(pthread_atfork(dispatch_atfork_prepare,
dispatch_atfork_parent, dispatch_atfork_child));
#endif
_dispatch_hw_config_init();
_dispatch_vtable_init();
_os_object_init();
_dispatch_introspection_init();
}
DISPATCH_EXPORT DISPATCH_NOTHROW
void
dispatch_atfork_child(void)
{
void *crash = (void *)0x100;
size_t i;
if (_dispatch_safe_fork) {
return;
}
_dispatch_child_of_unsafe_fork = true;
_dispatch_main_q.dq_items_head = crash;
_dispatch_main_q.dq_items_tail = crash;
_dispatch_mgr_q.dq_items_head = crash;
_dispatch_mgr_q.dq_items_tail = crash;
for (i = 0; i < DISPATCH_ROOT_QUEUE_COUNT; i++) {
_dispatch_root_queues[i].dq_items_head = crash;
_dispatch_root_queues[i].dq_items_tail = crash;
}
}
#pragma mark -
#pragma mark dispatch_queue_t
unsigned long volatile _dispatch_queue_serial_numbers = 12;
dispatch_queue_t
dispatch_queue_create_with_target(const char *label,
dispatch_queue_attr_t attr, dispatch_queue_t tq)
{
dispatch_queue_t dq;
dq = _dispatch_alloc(DISPATCH_VTABLE(queue),
sizeof(struct dispatch_queue_s) - DISPATCH_QUEUE_CACHELINE_PAD);
_dispatch_queue_init(dq);
if (label) {
dq->dq_label = strdup(label);
}
if (attr == DISPATCH_QUEUE_CONCURRENT) {
dq->dq_width = UINT32_MAX;
if (!tq) {
tq = _dispatch_get_root_queue(0, false);
}
} else {
if (!tq) {
tq = _dispatch_get_root_queue(0, true);
}
if (slowpath(attr)) {
dispatch_debug_assert(!attr, "Invalid attribute");
}
}
dq->do_targetq = tq;
_dispatch_object_debug(dq, "%s", __func__);
return _dispatch_introspection_queue_create(dq);
}
dispatch_queue_t
dispatch_queue_create(const char *label, dispatch_queue_attr_t attr)
{
return dispatch_queue_create_with_target(label, attr,
DISPATCH_TARGET_QUEUE_DEFAULT);
}
void
_dispatch_queue_destroy(dispatch_object_t dou)
{
dispatch_queue_t dq = dou._dq;
if (slowpath(dq == _dispatch_queue_get_current())) {
DISPATCH_CRASH("Release of a queue by itself");
}
if (slowpath(dq->dq_items_tail)) {
DISPATCH_CRASH("Release of a queue while items are enqueued");
}
dq->dq_items_tail = (void *)0x200;
dispatch_queue_t dqsq = dispatch_atomic_xchg2o(dq, dq_specific_q,
(void *)0x200, relaxed);
if (dqsq) {
_dispatch_release(dqsq);
}
}
void
_dispatch_queue_dispose(dispatch_queue_t dq)
{
_dispatch_object_debug(dq, "%s", __func__);
_dispatch_introspection_queue_dispose(dq);
if (dq->dq_label) {
free((void*)dq->dq_label);
}
_dispatch_queue_destroy(dq);
}
const char *
dispatch_queue_get_label(dispatch_queue_t dq)
{
if (slowpath(dq == DISPATCH_CURRENT_QUEUE_LABEL)) {
dq = _dispatch_get_current_queue();
}
return dq->dq_label ? dq->dq_label : "";
}
static void
_dispatch_queue_set_width2(void *ctxt)
{
int w = (int)(intptr_t)ctxt; uint32_t tmp;
dispatch_queue_t dq = _dispatch_queue_get_current();
if (w == 1 || w == 0) {
dq->dq_width = 1;
_dispatch_object_debug(dq, "%s", __func__);
return;
}
if (w > 0) {
tmp = (unsigned int)w;
} else switch (w) {
case DISPATCH_QUEUE_WIDTH_MAX_PHYSICAL_CPUS:
tmp = _dispatch_hw_config.cc_max_physical;
break;
case DISPATCH_QUEUE_WIDTH_ACTIVE_CPUS:
tmp = _dispatch_hw_config.cc_max_active;
break;
default:
case DISPATCH_QUEUE_WIDTH_MAX_LOGICAL_CPUS:
tmp = _dispatch_hw_config.cc_max_logical;
break;
}
dq->dq_width = tmp * 2;
_dispatch_object_debug(dq, "%s", __func__);
}
void
dispatch_queue_set_width(dispatch_queue_t dq, long width)
{
if (slowpath(dq->do_ref_cnt == DISPATCH_OBJECT_GLOBAL_REFCNT) ||
slowpath(dx_type(dq) == DISPATCH_QUEUE_ROOT_TYPE)) {
return;
}
_dispatch_barrier_trysync_f(dq, (void*)(intptr_t)width,
_dispatch_queue_set_width2);
}
static void
_dispatch_set_target_queue2(void *ctxt)
{
dispatch_queue_t prev_dq, dq = _dispatch_queue_get_current();
prev_dq = dq->do_targetq;
dq->do_targetq = ctxt;
_dispatch_release(prev_dq);
_dispatch_object_debug(dq, "%s", __func__);
}
void
dispatch_set_target_queue(dispatch_object_t dou, dispatch_queue_t dq)
{
DISPATCH_OBJECT_TFB(_dispatch_objc_set_target_queue, dou, dq);
if (slowpath(dou._do->do_ref_cnt == DISPATCH_OBJECT_GLOBAL_REFCNT) ||
slowpath(dx_type(dou._do) == DISPATCH_QUEUE_ROOT_TYPE)) {
return;
}
unsigned long type = dx_metatype(dou._do);
if (slowpath(!dq)) {
bool is_concurrent_q = (type == _DISPATCH_QUEUE_TYPE &&
slowpath(dou._dq->dq_width > 1));
dq = _dispatch_get_root_queue(0, !is_concurrent_q);
}
switch(type) {
case _DISPATCH_QUEUE_TYPE:
case _DISPATCH_SOURCE_TYPE:
_dispatch_retain(dq);
return _dispatch_barrier_trysync_f(dou._dq, dq,
_dispatch_set_target_queue2);
case _DISPATCH_IO_TYPE:
return _dispatch_io_set_target_queue(dou._dchannel, dq);
default: {
dispatch_queue_t prev_dq;
_dispatch_retain(dq);
prev_dq = dispatch_atomic_xchg2o(dou._do, do_targetq, dq, release);
if (prev_dq) _dispatch_release(prev_dq);
_dispatch_object_debug(dou._do, "%s", __func__);
return;
}
}
}
#pragma mark -
#pragma mark dispatch_pthread_root_queue
struct dispatch_pthread_root_queue_context_s {
pthread_attr_t dpq_thread_attr;
dispatch_block_t dpq_thread_configure;
struct dispatch_semaphore_s dpq_thread_mediator;
};
typedef struct dispatch_pthread_root_queue_context_s *
dispatch_pthread_root_queue_context_t;
#if DISPATCH_ENABLE_PTHREAD_ROOT_QUEUES
static struct dispatch_pthread_root_queue_context_s
_dispatch_mgr_root_queue_pthread_context;
static struct dispatch_root_queue_context_s
_dispatch_mgr_root_queue_context = {{{
#if HAVE_PTHREAD_WORKQUEUES
.dgq_kworkqueue = (void*)(~0ul),
#endif
.dgq_ctxt = &_dispatch_mgr_root_queue_pthread_context,
.dgq_thread_pool_size = 1,
}}};
static struct dispatch_queue_s _dispatch_mgr_root_queue = {
.do_vtable = DISPATCH_VTABLE(queue_root),
.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
.do_suspend_cnt = DISPATCH_OBJECT_SUSPEND_LOCK,
.do_ctxt = &_dispatch_mgr_root_queue_context,
.dq_label = "com.apple.root.libdispatch-manager",
.dq_running = 2,
.dq_width = UINT32_MAX,
.dq_serialnum = 3,
};
static struct {
volatile int prio;
int policy;
pthread_t tid;
} _dispatch_mgr_sched;
static dispatch_once_t _dispatch_mgr_sched_pred;
static void
_dispatch_mgr_sched_init(void *ctxt DISPATCH_UNUSED)
{
struct sched_param param;
pthread_attr_t *attr;
attr = &_dispatch_mgr_root_queue_pthread_context.dpq_thread_attr;
(void)dispatch_assume_zero(pthread_attr_init(attr));
(void)dispatch_assume_zero(pthread_attr_getschedpolicy(attr,
&_dispatch_mgr_sched.policy));
(void)dispatch_assume_zero(pthread_attr_getschedparam(attr, ¶m));
_dispatch_mgr_sched.prio = param.sched_priority + 2;
}
DISPATCH_NOINLINE
static pthread_t *
_dispatch_mgr_root_queue_init(void)
{
dispatch_once_f(&_dispatch_mgr_sched_pred, NULL, _dispatch_mgr_sched_init);
struct sched_param param;
pthread_attr_t *attr;
attr = &_dispatch_mgr_root_queue_pthread_context.dpq_thread_attr;
(void)dispatch_assume_zero(pthread_attr_setdetachstate(attr,
PTHREAD_CREATE_DETACHED));
#if !DISPATCH_DEBUG
(void)dispatch_assume_zero(pthread_attr_setstacksize(attr, 64 * 1024));
#endif
param.sched_priority = _dispatch_mgr_sched.prio;
(void)dispatch_assume_zero(pthread_attr_setschedparam(attr, ¶m));
return &_dispatch_mgr_sched.tid;
}
static inline void
_dispatch_mgr_priority_apply(void)
{
struct sched_param param;
do {
param.sched_priority = _dispatch_mgr_sched.prio;
(void)dispatch_assume_zero(pthread_setschedparam(
_dispatch_mgr_sched.tid, _dispatch_mgr_sched.policy, ¶m));
} while (_dispatch_mgr_sched.prio > param.sched_priority);
}
DISPATCH_NOINLINE
void
_dispatch_mgr_priority_init(void)
{
struct sched_param param;
pthread_attr_t *attr;
attr = &_dispatch_mgr_root_queue_pthread_context.dpq_thread_attr;
(void)dispatch_assume_zero(pthread_attr_getschedparam(attr, ¶m));
if (slowpath(_dispatch_mgr_sched.prio > param.sched_priority)) {
return _dispatch_mgr_priority_apply();
}
}
DISPATCH_NOINLINE
static void
_dispatch_mgr_priority_raise(const pthread_attr_t *attr)
{
dispatch_once_f(&_dispatch_mgr_sched_pred, NULL, _dispatch_mgr_sched_init);
struct sched_param param;
(void)dispatch_assume_zero(pthread_attr_getschedparam(attr, ¶m));
int p = _dispatch_mgr_sched.prio;
do if (p >= param.sched_priority) {
return;
} while (slowpath(!dispatch_atomic_cmpxchgvw2o(&_dispatch_mgr_sched, prio,
p, param.sched_priority, &p, relaxed)));
if (_dispatch_mgr_sched.tid) {
return _dispatch_mgr_priority_apply();
}
}
dispatch_queue_t
dispatch_pthread_root_queue_create(const char *label, unsigned long flags,
const pthread_attr_t *attr, dispatch_block_t configure)
{
dispatch_queue_t dq;
dispatch_root_queue_context_t qc;
dispatch_pthread_root_queue_context_t pqc;
size_t dqs;
if (slowpath(flags)) {
return NULL;
}
dqs = sizeof(struct dispatch_queue_s) - DISPATCH_QUEUE_CACHELINE_PAD;
dq = _dispatch_alloc(DISPATCH_VTABLE(queue_root), dqs +
sizeof(struct dispatch_root_queue_context_s) +
sizeof(struct dispatch_pthread_root_queue_context_s));
qc = (void*)dq + dqs;
pqc = (void*)qc + sizeof(struct dispatch_root_queue_context_s);
_dispatch_queue_init(dq);
if (label) {
dq->dq_label = strdup(label);
}
dq->do_suspend_cnt = DISPATCH_OBJECT_SUSPEND_LOCK;
dq->do_ctxt = qc;
dq->do_targetq = NULL;
dq->dq_running = 2;
dq->dq_width = UINT32_MAX;
pqc->dpq_thread_mediator.do_vtable = DISPATCH_VTABLE(semaphore);
qc->dgq_thread_mediator = &pqc->dpq_thread_mediator;
qc->dgq_ctxt = pqc;
#if HAVE_PTHREAD_WORKQUEUES
qc->dgq_kworkqueue = (void*)(~0ul);
#endif
_dispatch_root_queue_init_pthread_pool(qc, true);
if (attr) {
memcpy(&pqc->dpq_thread_attr, attr, sizeof(pthread_attr_t));
_dispatch_mgr_priority_raise(&pqc->dpq_thread_attr);
} else {
(void)dispatch_assume_zero(pthread_attr_init(&pqc->dpq_thread_attr));
}
(void)dispatch_assume_zero(pthread_attr_setdetachstate(
&pqc->dpq_thread_attr, PTHREAD_CREATE_DETACHED));
if (configure) {
pqc->dpq_thread_configure = _dispatch_Block_copy(configure);
}
_dispatch_object_debug(dq, "%s", __func__);
return _dispatch_introspection_queue_create(dq);
}
#endif
void
_dispatch_pthread_root_queue_dispose(dispatch_queue_t dq)
{
if (slowpath(dq->do_ref_cnt == DISPATCH_OBJECT_GLOBAL_REFCNT)) {
DISPATCH_CRASH("Global root queue disposed");
}
_dispatch_object_debug(dq, "%s", __func__);
_dispatch_introspection_queue_dispose(dq);
#if DISPATCH_USE_PTHREAD_POOL
dispatch_root_queue_context_t qc = dq->do_ctxt;
dispatch_pthread_root_queue_context_t pqc = qc->dgq_ctxt;
_dispatch_semaphore_dispose(qc->dgq_thread_mediator);
if (pqc->dpq_thread_configure) {
Block_release(pqc->dpq_thread_configure);
}
dq->do_targetq = _dispatch_get_root_queue(0, false);
#endif
if (dq->dq_label) {
free((void*)dq->dq_label);
}
_dispatch_queue_destroy(dq);
}
#pragma mark -
#pragma mark dispatch_queue_specific
struct dispatch_queue_specific_queue_s {
DISPATCH_STRUCT_HEADER(queue_specific_queue);
DISPATCH_QUEUE_HEADER;
TAILQ_HEAD(dispatch_queue_specific_head_s,
dispatch_queue_specific_s) dqsq_contexts;
};
struct dispatch_queue_specific_s {
const void *dqs_key;
void *dqs_ctxt;
dispatch_function_t dqs_destructor;
TAILQ_ENTRY(dispatch_queue_specific_s) dqs_list;
};
DISPATCH_DECL(dispatch_queue_specific);
void
_dispatch_queue_specific_queue_dispose(dispatch_queue_specific_queue_t dqsq)
{
dispatch_queue_specific_t dqs, tmp;
TAILQ_FOREACH_SAFE(dqs, &dqsq->dqsq_contexts, dqs_list, tmp) {
if (dqs->dqs_destructor) {
dispatch_async_f(_dispatch_get_root_queue(
DISPATCH_QUEUE_PRIORITY_DEFAULT, false), dqs->dqs_ctxt,
dqs->dqs_destructor);
}
free(dqs);
}
_dispatch_queue_destroy((dispatch_queue_t)dqsq);
}
static void
_dispatch_queue_init_specific(dispatch_queue_t dq)
{
dispatch_queue_specific_queue_t dqsq;
dqsq = _dispatch_alloc(DISPATCH_VTABLE(queue_specific_queue),
sizeof(struct dispatch_queue_specific_queue_s));
_dispatch_queue_init((dispatch_queue_t)dqsq);
dqsq->do_xref_cnt = -1;
dqsq->do_targetq = _dispatch_get_root_queue(DISPATCH_QUEUE_PRIORITY_HIGH,
true);
dqsq->dq_width = UINT32_MAX;
dqsq->dq_label = "queue-specific";
TAILQ_INIT(&dqsq->dqsq_contexts);
if (slowpath(!dispatch_atomic_cmpxchg2o(dq, dq_specific_q, NULL,
(dispatch_queue_t)dqsq, release))) {
_dispatch_release((dispatch_queue_t)dqsq);
}
}
static void
_dispatch_queue_set_specific(void *ctxt)
{
dispatch_queue_specific_t dqs, dqsn = ctxt;
dispatch_queue_specific_queue_t dqsq =
(dispatch_queue_specific_queue_t)_dispatch_queue_get_current();
TAILQ_FOREACH(dqs, &dqsq->dqsq_contexts, dqs_list) {
if (dqs->dqs_key == dqsn->dqs_key) {
if (dqs->dqs_destructor) {
dispatch_async_f(_dispatch_get_root_queue(
DISPATCH_QUEUE_PRIORITY_DEFAULT, false), dqs->dqs_ctxt,
dqs->dqs_destructor);
}
if (dqsn->dqs_ctxt) {
dqs->dqs_ctxt = dqsn->dqs_ctxt;
dqs->dqs_destructor = dqsn->dqs_destructor;
} else {
TAILQ_REMOVE(&dqsq->dqsq_contexts, dqs, dqs_list);
free(dqs);
}
return free(dqsn);
}
}
TAILQ_INSERT_TAIL(&dqsq->dqsq_contexts, dqsn, dqs_list);
}
DISPATCH_NOINLINE
void
dispatch_queue_set_specific(dispatch_queue_t dq, const void *key,
void *ctxt, dispatch_function_t destructor)
{
if (slowpath(!key)) {
return;
}
dispatch_queue_specific_t dqs;
dqs = _dispatch_calloc(1, sizeof(struct dispatch_queue_specific_s));
dqs->dqs_key = key;
dqs->dqs_ctxt = ctxt;
dqs->dqs_destructor = destructor;
if (slowpath(!dq->dq_specific_q)) {
_dispatch_queue_init_specific(dq);
}
_dispatch_barrier_trysync_f(dq->dq_specific_q, dqs,
_dispatch_queue_set_specific);
}
static void
_dispatch_queue_get_specific(void *ctxt)
{
void **ctxtp = ctxt;
void *key = *ctxtp;
dispatch_queue_specific_queue_t dqsq =
(dispatch_queue_specific_queue_t)_dispatch_queue_get_current();
dispatch_queue_specific_t dqs;
TAILQ_FOREACH(dqs, &dqsq->dqsq_contexts, dqs_list) {
if (dqs->dqs_key == key) {
*ctxtp = dqs->dqs_ctxt;
return;
}
}
*ctxtp = NULL;
}
DISPATCH_NOINLINE
void *
dispatch_queue_get_specific(dispatch_queue_t dq, const void *key)
{
if (slowpath(!key)) {
return NULL;
}
void *ctxt = NULL;
if (fastpath(dq->dq_specific_q)) {
ctxt = (void *)key;
dispatch_sync_f(dq->dq_specific_q, &ctxt, _dispatch_queue_get_specific);
}
return ctxt;
}
DISPATCH_NOINLINE
void *
dispatch_get_specific(const void *key)
{
if (slowpath(!key)) {
return NULL;
}
void *ctxt = NULL;
dispatch_queue_t dq = _dispatch_queue_get_current();
while (slowpath(dq)) {
if (slowpath(dq->dq_specific_q)) {
ctxt = (void *)key;
dispatch_sync_f(dq->dq_specific_q, &ctxt,
_dispatch_queue_get_specific);
if (ctxt) break;
}
dq = dq->do_targetq;
}
return ctxt;
}
#pragma mark -
#pragma mark dispatch_queue_debug
size_t
_dispatch_queue_debug_attr(dispatch_queue_t dq, char* buf, size_t bufsiz)
{
size_t offset = 0;
dispatch_queue_t target = dq->do_targetq;
offset += dsnprintf(buf, bufsiz, "target = %s[%p], width = 0x%x, "
"running = 0x%x, barrier = %d ", target && target->dq_label ?
target->dq_label : "", target, dq->dq_width / 2,
dq->dq_running / 2, dq->dq_running & 1);
if (dq->dq_is_thread_bound) {
offset += dsnprintf(buf, bufsiz, ", thread = %p ",
_dispatch_queue_get_bound_thread(dq));
}
return offset;
}
size_t
dispatch_queue_debug(dispatch_queue_t dq, char* buf, size_t bufsiz)
{
size_t offset = 0;
offset += dsnprintf(&buf[offset], bufsiz - offset, "%s[%p] = { ",
dq->dq_label ? dq->dq_label : dx_kind(dq), dq);
offset += _dispatch_object_debug_attr(dq, &buf[offset], bufsiz - offset);
offset += _dispatch_queue_debug_attr(dq, &buf[offset], bufsiz - offset);
offset += dsnprintf(&buf[offset], bufsiz - offset, "}");
return offset;
}
#if DISPATCH_DEBUG
void
dispatch_debug_queue(dispatch_queue_t dq, const char* str) {
if (fastpath(dq)) {
_dispatch_object_debug(dq, "%s", str);
} else {
_dispatch_log("queue[NULL]: %s", str);
}
}
#endif
#if DISPATCH_PERF_MON
static OSSpinLock _dispatch_stats_lock;
static struct {
uint64_t time_total;
uint64_t count_total;
uint64_t thread_total;
} _dispatch_stats[65];
static void
_dispatch_queue_merge_stats(uint64_t start)
{
uint64_t avg, delta = _dispatch_absolute_time() - start;
unsigned long count, bucket;
count = (size_t)_dispatch_thread_getspecific(dispatch_bcounter_key);
_dispatch_thread_setspecific(dispatch_bcounter_key, NULL);
if (count) {
avg = delta / count;
bucket = flsll(avg);
} else {
bucket = 0;
}
OSSpinLockLock(&_dispatch_stats_lock);
_dispatch_stats[bucket].time_total += delta;
_dispatch_stats[bucket].count_total += count;
_dispatch_stats[bucket].thread_total++;
OSSpinLockUnlock(&_dispatch_stats_lock);
}
#endif
#pragma mark -
#pragma mark dispatch_continuation_t
static void
_dispatch_force_cache_cleanup(void)
{
dispatch_continuation_t dc;
dc = _dispatch_thread_getspecific(dispatch_cache_key);
if (dc) {
_dispatch_thread_setspecific(dispatch_cache_key, NULL);
_dispatch_cache_cleanup(dc);
}
}
DISPATCH_NOINLINE
static void
_dispatch_cache_cleanup(void *value)
{
dispatch_continuation_t dc, next_dc = value;
while ((dc = next_dc)) {
next_dc = dc->do_next;
_dispatch_continuation_free_to_heap(dc);
}
}
#if DISPATCH_USE_MEMORYSTATUS_SOURCE
int _dispatch_continuation_cache_limit = DISPATCH_CONTINUATION_CACHE_LIMIT;
DISPATCH_NOINLINE
void
_dispatch_continuation_free_to_cache_limit(dispatch_continuation_t dc)
{
_dispatch_continuation_free_to_heap(dc);
dispatch_continuation_t next_dc;
dc = _dispatch_thread_getspecific(dispatch_cache_key);
int cnt;
if (!dc || (cnt = dc->do_ref_cnt-_dispatch_continuation_cache_limit) <= 0) {
return;
}
do {
next_dc = dc->do_next;
_dispatch_continuation_free_to_heap(dc);
} while (--cnt && (dc = next_dc));
_dispatch_thread_setspecific(dispatch_cache_key, next_dc);
}
#endif
DISPATCH_ALWAYS_INLINE_NDEBUG
static inline void
_dispatch_continuation_redirect(dispatch_queue_t dq, dispatch_object_t dou)
{
dispatch_continuation_t dc = dou._dc;
(void)dispatch_atomic_add2o(dq, dq_running, 2, acquire);
if (!DISPATCH_OBJ_IS_VTABLE(dc) &&
(long)dc->do_vtable & DISPATCH_OBJ_SYNC_SLOW_BIT) {
_dispatch_trace_continuation_pop(dq, dou);
_dispatch_thread_semaphore_signal(
(_dispatch_thread_semaphore_t)dc->dc_other);
_dispatch_introspection_queue_item_complete(dou);
} else {
_dispatch_async_f_redirect(dq, dc);
}
_dispatch_perfmon_workitem_inc();
}
DISPATCH_ALWAYS_INLINE_NDEBUG
static inline void
_dispatch_continuation_pop(dispatch_object_t dou)
{
dispatch_continuation_t dc = dou._dc, dc1;
dispatch_group_t dg;
_dispatch_trace_continuation_pop(_dispatch_queue_get_current(), dou);
if (DISPATCH_OBJ_IS_VTABLE(dou._do)) {
return dx_invoke(dou._do);
}
if ((long)dc->do_vtable & DISPATCH_OBJ_ASYNC_BIT) {
dc1 = _dispatch_continuation_free_cacheonly(dc);
} else {
dc1 = NULL;
}
if ((long)dc->do_vtable & DISPATCH_OBJ_GROUP_BIT) {
dg = dc->dc_data;
} else {
dg = NULL;
}
_dispatch_client_callout(dc->dc_ctxt, dc->dc_func);
if (dg) {
dispatch_group_leave(dg);
_dispatch_release(dg);
}
_dispatch_introspection_queue_item_complete(dou);
if (slowpath(dc1)) {
_dispatch_continuation_free_to_cache_limit(dc1);
}
}
#pragma mark -
#pragma mark dispatch_barrier_async
DISPATCH_NOINLINE
static void
_dispatch_barrier_async_f_slow(dispatch_queue_t dq, void *ctxt,
dispatch_function_t func)
{
dispatch_continuation_t dc = _dispatch_continuation_alloc_from_heap();
dc->do_vtable = (void *)(DISPATCH_OBJ_ASYNC_BIT | DISPATCH_OBJ_BARRIER_BIT);
dc->dc_func = func;
dc->dc_ctxt = ctxt;
_dispatch_queue_push(dq, dc);
}
DISPATCH_NOINLINE
void
dispatch_barrier_async_f(dispatch_queue_t dq, void *ctxt,
dispatch_function_t func)
{
dispatch_continuation_t dc;
dc = fastpath(_dispatch_continuation_alloc_cacheonly());
if (!dc) {
return _dispatch_barrier_async_f_slow(dq, ctxt, func);
}
dc->do_vtable = (void *)(DISPATCH_OBJ_ASYNC_BIT | DISPATCH_OBJ_BARRIER_BIT);
dc->dc_func = func;
dc->dc_ctxt = ctxt;
_dispatch_queue_push(dq, dc);
}
#ifdef __BLOCKS__
void
dispatch_barrier_async(dispatch_queue_t dq, void (^work)(void))
{
dispatch_barrier_async_f(dq, _dispatch_Block_copy(work),
_dispatch_call_block_and_release);
}
#endif
#pragma mark -
#pragma mark dispatch_async
void
_dispatch_async_redirect_invoke(void *ctxt)
{
struct dispatch_continuation_s *dc = ctxt;
struct dispatch_continuation_s *other_dc = dc->dc_other;
dispatch_queue_t old_dq, dq = dc->dc_data, rq;
old_dq = _dispatch_thread_getspecific(dispatch_queue_key);
_dispatch_thread_setspecific(dispatch_queue_key, dq);
_dispatch_continuation_pop(other_dc);
_dispatch_thread_setspecific(dispatch_queue_key, old_dq);
rq = dq->do_targetq;
while (slowpath(rq->do_targetq) && rq != old_dq) {
if (dispatch_atomic_sub2o(rq, dq_running, 2, relaxed) == 0) {
_dispatch_wakeup(rq);
}
rq = rq->do_targetq;
}
if (dispatch_atomic_sub2o(dq, dq_running, 2, relaxed) == 0) {
_dispatch_wakeup(dq);
}
_dispatch_release(dq);
}
static inline void
_dispatch_async_f_redirect2(dispatch_queue_t dq, dispatch_continuation_t dc)
{
uint32_t running = 2;
do {
if (slowpath(dq->dq_items_tail) ||
slowpath(DISPATCH_OBJECT_SUSPENDED(dq)) ||
slowpath(dq->dq_width == 1)) {
break;
}
running = dispatch_atomic_add2o(dq, dq_running, 2, relaxed);
if (slowpath(running & 1) || slowpath(running > dq->dq_width)) {
running = dispatch_atomic_sub2o(dq, dq_running, 2, relaxed);
break;
}
dq = dq->do_targetq;
} while (slowpath(dq->do_targetq));
_dispatch_queue_push_wakeup(dq, dc, running == 0);
}
DISPATCH_NOINLINE
static void
_dispatch_async_f_redirect(dispatch_queue_t dq,
dispatch_continuation_t other_dc)
{
dispatch_continuation_t dc = _dispatch_continuation_alloc();
dc->do_vtable = (void *)DISPATCH_OBJ_ASYNC_BIT;
dc->dc_func = _dispatch_async_redirect_invoke;
dc->dc_ctxt = dc;
dc->dc_data = dq;
dc->dc_other = other_dc;
_dispatch_retain(dq);
dq = dq->do_targetq;
if (slowpath(dq->do_targetq)) {
return _dispatch_async_f_redirect2(dq, dc);
}
_dispatch_queue_push(dq, dc);
}
DISPATCH_NOINLINE
static void
_dispatch_async_f2(dispatch_queue_t dq, dispatch_continuation_t dc)
{
uint32_t running = 2;
do {
if (slowpath(dq->dq_items_tail)
|| slowpath(DISPATCH_OBJECT_SUSPENDED(dq))) {
break;
}
running = dispatch_atomic_add2o(dq, dq_running, 2, relaxed);
if (slowpath(running > dq->dq_width)) {
running = dispatch_atomic_sub2o(dq, dq_running, 2, relaxed);
break;
}
if (!slowpath(running & 1)) {
return _dispatch_async_f_redirect(dq, dc);
}
running = dispatch_atomic_sub2o(dq, dq_running, 2, relaxed);
} while (!(running & 1));
_dispatch_queue_push_wakeup(dq, dc, running == 0);
}
DISPATCH_NOINLINE
static void
_dispatch_async_f_slow(dispatch_queue_t dq, void *ctxt,
dispatch_function_t func)
{
dispatch_continuation_t dc = _dispatch_continuation_alloc_from_heap();
dc->do_vtable = (void *)DISPATCH_OBJ_ASYNC_BIT;
dc->dc_func = func;
dc->dc_ctxt = ctxt;
if (dq->do_targetq) {
return _dispatch_async_f2(dq, dc);
}
_dispatch_queue_push(dq, dc);
}
DISPATCH_NOINLINE
void
dispatch_async_f(dispatch_queue_t dq, void *ctxt, dispatch_function_t func)
{
dispatch_continuation_t dc;
if (dq->dq_width == 1) {
return dispatch_barrier_async_f(dq, ctxt, func);
}
dc = fastpath(_dispatch_continuation_alloc_cacheonly());
if (!dc) {
return _dispatch_async_f_slow(dq, ctxt, func);
}
dc->do_vtable = (void *)DISPATCH_OBJ_ASYNC_BIT;
dc->dc_func = func;
dc->dc_ctxt = ctxt;
if (dq->do_targetq) {
return _dispatch_async_f2(dq, dc);
}
_dispatch_queue_push(dq, dc);
}
#ifdef __BLOCKS__
void
dispatch_async(dispatch_queue_t dq, void (^work)(void))
{
dispatch_async_f(dq, _dispatch_Block_copy(work),
_dispatch_call_block_and_release);
}
#endif
#pragma mark -
#pragma mark dispatch_group_async
DISPATCH_NOINLINE
void
dispatch_group_async_f(dispatch_group_t dg, dispatch_queue_t dq, void *ctxt,
dispatch_function_t func)
{
dispatch_continuation_t dc;
_dispatch_retain(dg);
dispatch_group_enter(dg);
dc = _dispatch_continuation_alloc();
dc->do_vtable = (void *)(DISPATCH_OBJ_ASYNC_BIT | DISPATCH_OBJ_GROUP_BIT);
dc->dc_func = func;
dc->dc_ctxt = ctxt;
dc->dc_data = dg;
if (dq->dq_width != 1 && dq->do_targetq) {
return _dispatch_async_f2(dq, dc);
}
_dispatch_queue_push(dq, dc);
}
#ifdef __BLOCKS__
void
dispatch_group_async(dispatch_group_t dg, dispatch_queue_t dq,
dispatch_block_t db)
{
dispatch_group_async_f(dg, dq, _dispatch_Block_copy(db),
_dispatch_call_block_and_release);
}
#endif
#pragma mark -
#pragma mark dispatch_function_invoke
DISPATCH_ALWAYS_INLINE
static inline void
_dispatch_function_invoke(dispatch_queue_t dq, void *ctxt,
dispatch_function_t func)
{
dispatch_queue_t old_dq = _dispatch_thread_getspecific(dispatch_queue_key);
_dispatch_thread_setspecific(dispatch_queue_key, dq);
_dispatch_client_callout(ctxt, func);
_dispatch_perfmon_workitem_inc();
_dispatch_thread_setspecific(dispatch_queue_key, old_dq);
}
void
_dispatch_sync_recurse_invoke(void *ctxt)
{
dispatch_continuation_t dc = ctxt;
_dispatch_function_invoke(dc->dc_data, dc->dc_ctxt, dc->dc_func);
}
DISPATCH_ALWAYS_INLINE
static inline void
_dispatch_function_recurse(dispatch_queue_t dq, void *ctxt,
dispatch_function_t func)
{
struct dispatch_continuation_s dc = {
.dc_data = dq,
.dc_func = func,
.dc_ctxt = ctxt,
};
dispatch_sync_f(dq->do_targetq, &dc, _dispatch_sync_recurse_invoke);
}
#pragma mark -
#pragma mark dispatch_barrier_sync
static void _dispatch_sync_f_invoke(dispatch_queue_t dq, void *ctxt,
dispatch_function_t func);
DISPATCH_ALWAYS_INLINE_NDEBUG
static inline _dispatch_thread_semaphore_t
_dispatch_barrier_sync_f_pop(dispatch_queue_t dq, dispatch_object_t dou,
bool lock)
{
_dispatch_thread_semaphore_t sema;
dispatch_continuation_t dc = dou._dc;
if (DISPATCH_OBJ_IS_VTABLE(dc) || ((long)dc->do_vtable &
(DISPATCH_OBJ_BARRIER_BIT | DISPATCH_OBJ_SYNC_SLOW_BIT)) !=
(DISPATCH_OBJ_BARRIER_BIT | DISPATCH_OBJ_SYNC_SLOW_BIT)) {
return 0;
}
_dispatch_trace_continuation_pop(dq, dc);
_dispatch_perfmon_workitem_inc();
dc = dc->dc_ctxt;
dq = dc->dc_data;
sema = (_dispatch_thread_semaphore_t)dc->dc_other;
if (lock) {
(void)dispatch_atomic_add2o(dq, do_suspend_cnt,
DISPATCH_OBJECT_SUSPEND_INTERVAL, relaxed);
(void)dispatch_atomic_add2o(dq, dq_running, 2, relaxed);
}
_dispatch_introspection_queue_item_complete(dou);
return sema ? sema : MACH_PORT_DEAD;
}
static void
_dispatch_barrier_sync_f_slow_invoke(void *ctxt)
{
dispatch_continuation_t dc = ctxt;
dispatch_queue_t dq = dc->dc_data;
_dispatch_thread_semaphore_t sema;
sema = (_dispatch_thread_semaphore_t)dc->dc_other;
dispatch_assert(dq == _dispatch_queue_get_current());
#if DISPATCH_COCOA_COMPAT
if (slowpath(dq->dq_is_thread_bound)) {
_dispatch_client_callout(dc->dc_ctxt, dc->dc_func);
dispatch_atomic_store2o(dc, dc_func, NULL, release);
_dispatch_thread_semaphore_signal(sema); return;
}
#endif
(void)dispatch_atomic_add2o(dq, do_suspend_cnt,
DISPATCH_OBJECT_SUSPEND_INTERVAL, relaxed);
(void)dispatch_atomic_add2o(dq, dq_running, 2, relaxed);
_dispatch_thread_semaphore_signal(sema); }
DISPATCH_NOINLINE
static void
_dispatch_barrier_sync_f_slow(dispatch_queue_t dq, void *ctxt,
dispatch_function_t func)
{
if (slowpath(!dq->do_targetq)) {
(void)dispatch_atomic_add2o(dq, dq_running, 2, relaxed);
return _dispatch_sync_f_invoke(dq, ctxt, func);
}
_dispatch_thread_semaphore_t sema = _dispatch_get_thread_semaphore();
struct dispatch_continuation_s dc = {
.dc_data = dq,
#if DISPATCH_COCOA_COMPAT
.dc_func = func,
.dc_ctxt = ctxt,
#endif
.dc_other = (void*)sema,
};
struct dispatch_continuation_s dbss = {
.do_vtable = (void *)(DISPATCH_OBJ_BARRIER_BIT |
DISPATCH_OBJ_SYNC_SLOW_BIT),
.dc_func = _dispatch_barrier_sync_f_slow_invoke,
.dc_ctxt = &dc,
#if DISPATCH_INTROSPECTION
.dc_data = (void*)_dispatch_thread_self(),
#endif
};
_dispatch_queue_push(dq, &dbss);
_dispatch_thread_semaphore_wait(sema); _dispatch_put_thread_semaphore(sema);
#if DISPATCH_COCOA_COMPAT
if (dc.dc_func == NULL) {
return;
}
#endif
if (slowpath(dq->do_targetq->do_targetq)) {
_dispatch_function_recurse(dq, ctxt, func);
} else {
_dispatch_function_invoke(dq, ctxt, func);
}
if (fastpath(dq->do_suspend_cnt < 2 * DISPATCH_OBJECT_SUSPEND_INTERVAL) &&
dq->dq_running == 2) {
sema = _dispatch_queue_drain_one_barrier_sync(dq);
if (sema) {
_dispatch_thread_semaphore_signal(sema); return;
}
}
(void)dispatch_atomic_sub2o(dq, do_suspend_cnt,
DISPATCH_OBJECT_SUSPEND_INTERVAL, relaxed);
if (slowpath(dispatch_atomic_sub2o(dq, dq_running, 2, release) == 0)) {
_dispatch_wakeup(dq);
}
}
DISPATCH_NOINLINE
static void
_dispatch_barrier_sync_f2(dispatch_queue_t dq)
{
if (!slowpath(DISPATCH_OBJECT_SUSPENDED(dq))) {
_dispatch_thread_semaphore_t sema;
sema = _dispatch_queue_drain_one_barrier_sync(dq);
if (sema) {
(void)dispatch_atomic_add2o(dq, do_suspend_cnt,
DISPATCH_OBJECT_SUSPEND_INTERVAL, relaxed);
(void)dispatch_atomic_inc2o(dq, dq_running, relaxed);
_dispatch_thread_semaphore_signal(sema);
return;
}
}
if (slowpath(dispatch_atomic_dec2o(dq, dq_running, release) == 0)) {
_dispatch_wakeup(dq);
}
}
DISPATCH_NOINLINE
static void
_dispatch_barrier_sync_f_invoke(dispatch_queue_t dq, void *ctxt,
dispatch_function_t func)
{
_dispatch_function_invoke(dq, ctxt, func);
if (slowpath(dq->dq_items_tail)) {
return _dispatch_barrier_sync_f2(dq);
}
if (slowpath(dispatch_atomic_dec2o(dq, dq_running, release) == 0)) {
_dispatch_wakeup(dq);
}
}
DISPATCH_NOINLINE
static void
_dispatch_barrier_sync_f_recurse(dispatch_queue_t dq, void *ctxt,
dispatch_function_t func)
{
_dispatch_function_recurse(dq, ctxt, func);
if (slowpath(dq->dq_items_tail)) {
return _dispatch_barrier_sync_f2(dq);
}
if (slowpath(dispatch_atomic_dec2o(dq, dq_running, release) == 0)) {
_dispatch_wakeup(dq);
}
}
DISPATCH_NOINLINE
void
dispatch_barrier_sync_f(dispatch_queue_t dq, void *ctxt,
dispatch_function_t func)
{
if (slowpath(dq->dq_items_tail) || slowpath(DISPATCH_OBJECT_SUSPENDED(dq))){
return _dispatch_barrier_sync_f_slow(dq, ctxt, func);
}
if (slowpath(!dispatch_atomic_cmpxchg2o(dq, dq_running, 0, 1, acquire))) {
return _dispatch_barrier_sync_f_slow(dq, ctxt, func);
}
if (slowpath(dq->do_targetq->do_targetq)) {
return _dispatch_barrier_sync_f_recurse(dq, ctxt, func);
}
_dispatch_barrier_sync_f_invoke(dq, ctxt, func);
}
#ifdef __BLOCKS__
#if DISPATCH_COCOA_COMPAT
DISPATCH_NOINLINE
static void
_dispatch_barrier_sync_slow(dispatch_queue_t dq, void (^work)(void))
{
if (dispatch_begin_thread_4GC) {
dispatch_block_t block = _dispatch_Block_copy(work);
return dispatch_barrier_sync_f(dq, block,
_dispatch_call_block_and_release);
}
dispatch_barrier_sync_f(dq, work, _dispatch_Block_invoke(work));
}
#endif
void
dispatch_barrier_sync(dispatch_queue_t dq, void (^work)(void))
{
#if DISPATCH_COCOA_COMPAT
if (slowpath(dq->dq_is_thread_bound)) {
return _dispatch_barrier_sync_slow(dq, work);
}
#endif
dispatch_barrier_sync_f(dq, work, _dispatch_Block_invoke(work));
}
#endif
DISPATCH_NOINLINE
static void
_dispatch_barrier_trysync_f_invoke(dispatch_queue_t dq, void *ctxt,
dispatch_function_t func)
{
_dispatch_function_invoke(dq, ctxt, func);
if (slowpath(dispatch_atomic_dec2o(dq, dq_running, release) == 0)) {
_dispatch_wakeup(dq);
}
}
DISPATCH_NOINLINE
void
_dispatch_barrier_trysync_f(dispatch_queue_t dq, void *ctxt,
dispatch_function_t func)
{
if (slowpath(dq->dq_items_tail) || slowpath(DISPATCH_OBJECT_SUSPENDED(dq))
|| slowpath(!dispatch_atomic_cmpxchg2o(dq, dq_running, 0, 1,
acquire))) {
return dispatch_barrier_async_f(dq, ctxt, func);
}
_dispatch_barrier_trysync_f_invoke(dq, ctxt, func);
}
#pragma mark -
#pragma mark dispatch_sync
DISPATCH_NOINLINE
static void
_dispatch_sync_f_slow(dispatch_queue_t dq, void *ctxt, dispatch_function_t func,
bool wakeup)
{
_dispatch_thread_semaphore_t sema = _dispatch_get_thread_semaphore();
struct dispatch_continuation_s dss = {
.do_vtable = (void*)DISPATCH_OBJ_SYNC_SLOW_BIT,
#if DISPATCH_INTROSPECTION
.dc_func = func,
.dc_ctxt = ctxt,
.dc_data = (void*)_dispatch_thread_self(),
#endif
.dc_other = (void*)sema,
};
_dispatch_queue_push_wakeup(dq, &dss, wakeup);
_dispatch_thread_semaphore_wait(sema);
_dispatch_put_thread_semaphore(sema);
if (slowpath(dq->do_targetq->do_targetq)) {
_dispatch_function_recurse(dq, ctxt, func);
} else {
_dispatch_function_invoke(dq, ctxt, func);
}
if (slowpath(dispatch_atomic_sub2o(dq, dq_running, 2, relaxed) == 0)) {
_dispatch_wakeup(dq);
}
}
DISPATCH_NOINLINE
static void
_dispatch_sync_f_invoke(dispatch_queue_t dq, void *ctxt,
dispatch_function_t func)
{
_dispatch_function_invoke(dq, ctxt, func);
if (slowpath(dispatch_atomic_sub2o(dq, dq_running, 2, relaxed) == 0)) {
_dispatch_wakeup(dq);
}
}
DISPATCH_NOINLINE
static void
_dispatch_sync_f_recurse(dispatch_queue_t dq, void *ctxt,
dispatch_function_t func)
{
_dispatch_function_recurse(dq, ctxt, func);
if (slowpath(dispatch_atomic_sub2o(dq, dq_running, 2, relaxed) == 0)) {
_dispatch_wakeup(dq);
}
}
static inline void
_dispatch_sync_f2(dispatch_queue_t dq, void *ctxt, dispatch_function_t func)
{
if (slowpath(dq->dq_items_tail) || slowpath(DISPATCH_OBJECT_SUSPENDED(dq))){
return _dispatch_sync_f_slow(dq, ctxt, func, false);
}
uint32_t running = dispatch_atomic_add2o(dq, dq_running, 2, relaxed);
if (slowpath(running & 1) || slowpath(DISPATCH_OBJECT_SUSPENDED(dq))) {
running = dispatch_atomic_sub2o(dq, dq_running, 2, relaxed);
return _dispatch_sync_f_slow(dq, ctxt, func, running == 0);
}
if (slowpath(dq->do_targetq->do_targetq)) {
return _dispatch_sync_f_recurse(dq, ctxt, func);
}
_dispatch_sync_f_invoke(dq, ctxt, func);
}
DISPATCH_NOINLINE
void
dispatch_sync_f(dispatch_queue_t dq, void *ctxt, dispatch_function_t func)
{
if (fastpath(dq->dq_width == 1)) {
return dispatch_barrier_sync_f(dq, ctxt, func);
}
if (slowpath(!dq->do_targetq)) {
(void)dispatch_atomic_add2o(dq, dq_running, 2, relaxed);
return _dispatch_sync_f_invoke(dq, ctxt, func);
}
_dispatch_sync_f2(dq, ctxt, func);
}
#ifdef __BLOCKS__
#if DISPATCH_COCOA_COMPAT
DISPATCH_NOINLINE
static void
_dispatch_sync_slow(dispatch_queue_t dq, void (^work)(void))
{
if (dispatch_begin_thread_4GC) {
dispatch_block_t block = _dispatch_Block_copy(work);
return dispatch_sync_f(dq, block, _dispatch_call_block_and_release);
}
dispatch_sync_f(dq, work, _dispatch_Block_invoke(work));
}
#endif
void
dispatch_sync(dispatch_queue_t dq, void (^work)(void))
{
#if DISPATCH_COCOA_COMPAT
if (slowpath(dq->dq_is_thread_bound)) {
return _dispatch_sync_slow(dq, work);
}
#endif
dispatch_sync_f(dq, work, _dispatch_Block_invoke(work));
}
#endif
#pragma mark -
#pragma mark dispatch_after
void
_dispatch_after_timer_callback(void *ctxt)
{
dispatch_continuation_t dc = ctxt, dc1;
dispatch_source_t ds = dc->dc_data;
dc1 = _dispatch_continuation_free_cacheonly(dc);
_dispatch_client_callout(dc->dc_ctxt, dc->dc_func);
dispatch_source_cancel(ds);
dispatch_release(ds);
if (slowpath(dc1)) {
_dispatch_continuation_free_to_cache_limit(dc1);
}
}
DISPATCH_NOINLINE
void
dispatch_after_f(dispatch_time_t when, dispatch_queue_t queue, void *ctxt,
dispatch_function_t func)
{
uint64_t delta, leeway;
dispatch_source_t ds;
if (when == DISPATCH_TIME_FOREVER) {
#if DISPATCH_DEBUG
DISPATCH_CLIENT_CRASH(
"dispatch_after_f() called with 'when' == infinity");
#endif
return;
}
delta = _dispatch_timeout(when);
if (delta == 0) {
return dispatch_async_f(queue, ctxt, func);
}
leeway = delta / 10; if (leeway < NSEC_PER_MSEC) leeway = NSEC_PER_MSEC;
if (leeway > 60 * NSEC_PER_SEC) leeway = 60 * NSEC_PER_SEC;
ds = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, queue);
dispatch_assert(ds);
dispatch_continuation_t dc = _dispatch_continuation_alloc();
dc->do_vtable = (void *)(DISPATCH_OBJ_ASYNC_BIT | DISPATCH_OBJ_BARRIER_BIT);
dc->dc_func = func;
dc->dc_ctxt = ctxt;
dc->dc_data = ds;
dispatch_set_context(ds, dc);
dispatch_source_set_event_handler_f(ds, _dispatch_after_timer_callback);
dispatch_source_set_timer(ds, when, DISPATCH_TIME_FOREVER, leeway);
dispatch_resume(ds);
}
#ifdef __BLOCKS__
void
dispatch_after(dispatch_time_t when, dispatch_queue_t queue,
dispatch_block_t work)
{
if (when == DISPATCH_TIME_FOREVER) {
#if DISPATCH_DEBUG
DISPATCH_CLIENT_CRASH(
"dispatch_after() called with 'when' == infinity");
#endif
return;
}
dispatch_after_f(when, queue, _dispatch_Block_copy(work),
_dispatch_call_block_and_release);
}
#endif
#pragma mark -
#pragma mark dispatch_queue_push
DISPATCH_NOINLINE
static void
_dispatch_queue_push_list_slow2(dispatch_queue_t dq,
struct dispatch_object_s *obj)
{
_dispatch_retain(dq);
dq->dq_items_head = obj;
_dispatch_wakeup(dq);
_dispatch_release(dq);
}
DISPATCH_NOINLINE
void
_dispatch_queue_push_list_slow(dispatch_queue_t dq,
struct dispatch_object_s *obj, unsigned int n)
{
if (dx_type(dq) == DISPATCH_QUEUE_ROOT_TYPE && !dq->dq_is_thread_bound) {
dispatch_atomic_store2o(dq, dq_items_head, obj, relaxed);
return _dispatch_queue_wakeup_global2(dq, n);
}
_dispatch_queue_push_list_slow2(dq, obj);
}
DISPATCH_NOINLINE
void
_dispatch_queue_push_slow(dispatch_queue_t dq,
struct dispatch_object_s *obj)
{
if (dx_type(dq) == DISPATCH_QUEUE_ROOT_TYPE && !dq->dq_is_thread_bound) {
dispatch_atomic_store2o(dq, dq_items_head, obj, relaxed);
return _dispatch_queue_wakeup_global(dq);
}
_dispatch_queue_push_list_slow2(dq, obj);
}
#pragma mark -
#pragma mark dispatch_queue_probe
unsigned long
_dispatch_queue_probe(dispatch_queue_t dq)
{
return (unsigned long)slowpath(dq->dq_items_tail != NULL);
}
#if DISPATCH_COCOA_COMPAT
unsigned long
_dispatch_runloop_queue_probe(dispatch_queue_t dq)
{
if (_dispatch_queue_probe(dq)) {
if (dq->do_xref_cnt == -1) return true; return _dispatch_runloop_queue_wakeup(dq);
}
return false;
}
#endif
unsigned long
_dispatch_mgr_queue_probe(dispatch_queue_t dq)
{
if (_dispatch_queue_probe(dq)) {
return _dispatch_mgr_wakeup(dq);
}
return false;
}
unsigned long
_dispatch_root_queue_probe(dispatch_queue_t dq)
{
_dispatch_queue_wakeup_global(dq);
return false;
}
#pragma mark -
#pragma mark dispatch_wakeup
dispatch_queue_t
_dispatch_wakeup(dispatch_object_t dou)
{
if (slowpath(DISPATCH_OBJECT_SUSPENDED(dou._do))) {
return NULL;
}
if (!dx_probe(dou._do)) {
return NULL;
}
if (!dispatch_atomic_cmpxchg2o(dou._do, do_suspend_cnt, 0,
DISPATCH_OBJECT_SUSPEND_LOCK, release)) {
#if DISPATCH_COCOA_COMPAT
if (dou._dq == &_dispatch_main_q) {
return _dispatch_main_queue_wakeup();
}
#endif
return NULL;
}
_dispatch_retain(dou._do);
dispatch_queue_t tq = dou._do->do_targetq;
_dispatch_queue_push(tq, dou._do);
return tq; }
#if DISPATCH_COCOA_COMPAT
static inline void
_dispatch_runloop_queue_wakeup_thread(dispatch_queue_t dq)
{
mach_port_t mp = (mach_port_t)dq->do_ctxt;
if (!mp) {
return;
}
kern_return_t kr = _dispatch_send_wakeup_runloop_thread(mp, 0);
switch (kr) {
case MACH_SEND_TIMEOUT:
case MACH_SEND_TIMED_OUT:
case MACH_SEND_INVALID_DEST:
break;
default:
(void)dispatch_assume_zero(kr);
break;
}
}
DISPATCH_NOINLINE DISPATCH_WEAK
unsigned long
_dispatch_runloop_queue_wakeup(dispatch_queue_t dq)
{
_dispatch_runloop_queue_wakeup_thread(dq);
return false;
}
DISPATCH_NOINLINE
static dispatch_queue_t
_dispatch_main_queue_wakeup(void)
{
dispatch_queue_t dq = &_dispatch_main_q;
if (!dq->dq_is_thread_bound) {
return NULL;
}
dispatch_once_f(&_dispatch_main_q_port_pred, dq,
_dispatch_runloop_queue_port_init);
_dispatch_runloop_queue_wakeup_thread(dq);
return NULL;
}
#endif
DISPATCH_NOINLINE
static void
_dispatch_queue_wakeup_global_slow(dispatch_queue_t dq, unsigned int n)
{
static dispatch_once_t pred;
dispatch_root_queue_context_t qc = dq->do_ctxt;
uint32_t i = n;
int r;
_dispatch_debug_root_queue(dq, __func__);
dispatch_once_f(&pred, NULL, _dispatch_root_queues_init);
#if HAVE_PTHREAD_WORKQUEUES
#if DISPATCH_USE_PTHREAD_POOL
if (qc->dgq_kworkqueue != (void*)(~0ul))
#endif
{
_dispatch_root_queue_debug("requesting new worker thread for global "
"queue: %p", dq);
#if DISPATCH_USE_LEGACY_WORKQUEUE_FALLBACK
if (qc->dgq_kworkqueue) {
pthread_workitem_handle_t wh;
unsigned int gen_cnt;
do {
r = pthread_workqueue_additem_np(qc->dgq_kworkqueue,
_dispatch_worker_thread3, dq, &wh, &gen_cnt);
(void)dispatch_assume_zero(r);
} while (--i);
return;
}
#endif // DISPATCH_USE_LEGACY_WORKQUEUE_FALLBACK
#if HAVE_PTHREAD_WORKQUEUE_SETDISPATCH_NP
r = pthread_workqueue_addthreads_np(qc->dgq_wq_priority,
qc->dgq_wq_options, (int)i);
(void)dispatch_assume_zero(r);
#endif
return;
}
#endif // HAVE_PTHREAD_WORKQUEUES
#if DISPATCH_USE_PTHREAD_POOL
if (fastpath(qc->dgq_thread_mediator)) {
while (dispatch_semaphore_signal(qc->dgq_thread_mediator)) {
if (!--i) {
return;
}
}
}
uint32_t j, t_count = qc->dgq_thread_pool_size;
do {
if (!t_count) {
_dispatch_root_queue_debug("pthread pool is full for root queue: "
"%p", dq);
return;
}
j = i > t_count ? t_count : i;
} while (!dispatch_atomic_cmpxchgvw2o(qc, dgq_thread_pool_size, t_count,
t_count - j, &t_count, relaxed));
dispatch_pthread_root_queue_context_t pqc = qc->dgq_ctxt;
pthread_attr_t *attr = pqc ? &pqc->dpq_thread_attr : NULL;
pthread_t tid, *pthr = &tid;
#if DISPATCH_ENABLE_PTHREAD_ROOT_QUEUES
if (slowpath(dq == &_dispatch_mgr_root_queue)) {
pthr = _dispatch_mgr_root_queue_init();
}
#endif
do {
_dispatch_retain(dq);
while ((r = pthread_create(pthr, attr, _dispatch_worker_thread, dq))) {
if (r != EAGAIN) {
(void)dispatch_assume_zero(r);
}
_dispatch_temporary_resource_shortage();
}
if (!attr) {
r = pthread_detach(*pthr);
(void)dispatch_assume_zero(r);
}
} while (--j);
#endif // DISPATCH_USE_PTHREAD_POOL
}
static inline void
_dispatch_queue_wakeup_global2(dispatch_queue_t dq, unsigned int n)
{
if (!dq->dq_items_tail) {
return;
}
#if HAVE_PTHREAD_WORKQUEUES
dispatch_root_queue_context_t qc = dq->do_ctxt;
if (
#if DISPATCH_USE_PTHREAD_POOL
(qc->dgq_kworkqueue != (void*)(~0ul)) &&
#endif
!dispatch_atomic_cmpxchg2o(qc, dgq_pending, 0, n, relaxed)) {
_dispatch_root_queue_debug("worker thread request still pending for "
"global queue: %p", dq);
return;
}
#endif // HAVE_PTHREAD_WORKQUEUES
return _dispatch_queue_wakeup_global_slow(dq, n);
}
static inline void
_dispatch_queue_wakeup_global(dispatch_queue_t dq)
{
return _dispatch_queue_wakeup_global2(dq, 1);
}
#pragma mark -
#pragma mark dispatch_queue_invoke
DISPATCH_ALWAYS_INLINE
static inline dispatch_queue_t
dispatch_queue_invoke2(dispatch_object_t dou,
_dispatch_thread_semaphore_t *sema_ptr)
{
dispatch_queue_t dq = dou._dq;
dispatch_queue_t otq = dq->do_targetq;
*sema_ptr = _dispatch_queue_drain(dq);
if (slowpath(otq != dq->do_targetq)) {
return dq->do_targetq;
}
return NULL;
}
DISPATCH_NOINLINE
void
_dispatch_queue_invoke(dispatch_queue_t dq)
{
_dispatch_queue_class_invoke(dq, dispatch_queue_invoke2);
}
#pragma mark -
#pragma mark dispatch_queue_drain
DISPATCH_ALWAYS_INLINE
static inline struct dispatch_object_s*
_dispatch_queue_head(dispatch_queue_t dq)
{
struct dispatch_object_s *dc;
while (!(dc = fastpath(dq->dq_items_head))) {
dispatch_hardware_pause();
}
return dc;
}
DISPATCH_ALWAYS_INLINE
static inline struct dispatch_object_s*
_dispatch_queue_next(dispatch_queue_t dq, struct dispatch_object_s *dc)
{
struct dispatch_object_s *next_dc;
next_dc = fastpath(dc->do_next);
dq->dq_items_head = next_dc;
if (!next_dc && !dispatch_atomic_cmpxchg2o(dq, dq_items_tail, dc, NULL,
relaxed)) {
while (!(next_dc = fastpath(dc->do_next))) {
dispatch_hardware_pause();
}
dq->dq_items_head = next_dc;
}
return next_dc;
}
_dispatch_thread_semaphore_t
_dispatch_queue_drain(dispatch_object_t dou)
{
dispatch_queue_t dq = dou._dq, orig_tq, old_dq;
old_dq = _dispatch_thread_getspecific(dispatch_queue_key);
struct dispatch_object_s *dc, *next_dc;
_dispatch_thread_semaphore_t sema = 0;
bool check_tq = (dx_type(dq) != DISPATCH_SOURCE_KEVENT_TYPE);
orig_tq = dq->do_targetq;
_dispatch_thread_setspecific(dispatch_queue_key, dq);
while (dq->dq_items_tail) {
dc = _dispatch_queue_head(dq);
do {
if (DISPATCH_OBJECT_SUSPENDED(dq)) {
goto out;
}
if (dq->dq_running > dq->dq_width) {
goto out;
}
if (slowpath(orig_tq != dq->do_targetq) && check_tq) {
goto out;
}
bool redirect = false;
if (!fastpath(dq->dq_width == 1)) {
if (!DISPATCH_OBJ_IS_VTABLE(dc) &&
(long)dc->do_vtable & DISPATCH_OBJ_BARRIER_BIT) {
if (dq->dq_running > 1) {
goto out;
}
} else {
redirect = true;
}
}
next_dc = _dispatch_queue_next(dq, dc);
if (redirect) {
_dispatch_continuation_redirect(dq, dc);
continue;
}
if ((sema = _dispatch_barrier_sync_f_pop(dq, dc, true))) {
goto out;
}
_dispatch_continuation_pop(dc);
_dispatch_perfmon_workitem_inc();
} while ((dc = next_dc));
}
out:
_dispatch_thread_setspecific(dispatch_queue_key, old_dq);
return sema;
}
#if DISPATCH_COCOA_COMPAT
static void
_dispatch_main_queue_drain(void)
{
dispatch_queue_t dq = &_dispatch_main_q;
if (!dq->dq_items_tail) {
return;
}
struct dispatch_continuation_s marker = {
.do_vtable = NULL,
};
struct dispatch_object_s *dmarker = (void*)▮
_dispatch_queue_push_notrace(dq, dmarker);
_dispatch_perfmon_start();
dispatch_queue_t old_dq = _dispatch_thread_getspecific(dispatch_queue_key);
_dispatch_thread_setspecific(dispatch_queue_key, dq);
struct dispatch_object_s *dc, *next_dc;
dc = _dispatch_queue_head(dq);
do {
next_dc = _dispatch_queue_next(dq, dc);
if (dc == dmarker) {
goto out;
}
_dispatch_continuation_pop(dc);
_dispatch_perfmon_workitem_inc();
} while ((dc = next_dc));
DISPATCH_CRASH("Main queue corruption");
out:
if (next_dc) {
_dispatch_main_queue_wakeup();
}
_dispatch_thread_setspecific(dispatch_queue_key, old_dq);
_dispatch_perfmon_end();
_dispatch_force_cache_cleanup();
}
static bool
_dispatch_runloop_queue_drain_one(dispatch_queue_t dq)
{
if (!dq->dq_items_tail) {
return false;
}
_dispatch_perfmon_start();
dispatch_queue_t old_dq = _dispatch_thread_getspecific(dispatch_queue_key);
_dispatch_thread_setspecific(dispatch_queue_key, dq);
struct dispatch_object_s *dc, *next_dc;
dc = _dispatch_queue_head(dq);
next_dc = _dispatch_queue_next(dq, dc);
_dispatch_continuation_pop(dc);
_dispatch_perfmon_workitem_inc();
_dispatch_thread_setspecific(dispatch_queue_key, old_dq);
_dispatch_perfmon_end();
_dispatch_force_cache_cleanup();
return next_dc;
}
#endif
DISPATCH_ALWAYS_INLINE_NDEBUG
static inline _dispatch_thread_semaphore_t
_dispatch_queue_drain_one_barrier_sync(dispatch_queue_t dq)
{
struct dispatch_object_s *dc;
_dispatch_thread_semaphore_t sema;
dc = dq->dq_items_head;
if (slowpath(!dc) || !(sema = _dispatch_barrier_sync_f_pop(dq, dc, false))){
return 0;
}
(void)_dispatch_queue_next(dq, dc);
return sema;
}
void
_dispatch_mgr_queue_drain(void)
{
dispatch_queue_t dq = &_dispatch_mgr_q;
if (!dq->dq_items_tail) {
return _dispatch_force_cache_cleanup();
}
_dispatch_perfmon_start();
if (slowpath(_dispatch_queue_drain(dq))) {
DISPATCH_CRASH("Sync onto manager queue");
}
_dispatch_perfmon_end();
_dispatch_force_cache_cleanup();
}
#pragma mark -
#pragma mark dispatch_root_queue_drain
#ifndef DISPATCH_CONTENTION_USE_RAND
#define DISPATCH_CONTENTION_USE_RAND (!TARGET_OS_EMBEDDED)
#endif
#ifndef DISPATCH_CONTENTION_SPINS_MAX
#define DISPATCH_CONTENTION_SPINS_MAX (128 - 1)
#endif
#ifndef DISPATCH_CONTENTION_SPINS_MIN
#define DISPATCH_CONTENTION_SPINS_MIN (32 - 1)
#endif
#ifndef DISPATCH_CONTENTION_USLEEP_START
#define DISPATCH_CONTENTION_USLEEP_START 500
#endif
#ifndef DISPATCH_CONTENTION_USLEEP_MAX
#define DISPATCH_CONTENTION_USLEEP_MAX 100000
#endif
DISPATCH_NOINLINE
static bool
_dispatch_queue_concurrent_drain_one_slow(dispatch_queue_t dq)
{
dispatch_root_queue_context_t qc = dq->do_ctxt;
struct dispatch_object_s *const mediator = (void *)~0ul;
bool pending = false, available = true;
unsigned int spins, sleep_time = DISPATCH_CONTENTION_USLEEP_START;
do {
#if DISPATCH_CONTENTION_USE_RAND
static unsigned int seed;
spins = (rand_r(&seed) & DISPATCH_CONTENTION_SPINS_MAX) |
DISPATCH_CONTENTION_SPINS_MIN;
#else
spins = DISPATCH_CONTENTION_SPINS_MIN +
(DISPATCH_CONTENTION_SPINS_MAX-DISPATCH_CONTENTION_SPINS_MIN)/2;
#endif
while (spins--) {
dispatch_hardware_pause();
if (fastpath(dq->dq_items_head != mediator)) goto out;
};
if (!pending) {
(void)dispatch_atomic_inc2o(qc, dgq_pending, relaxed);
pending = true;
}
_dispatch_contention_usleep(sleep_time);
if (fastpath(dq->dq_items_head != mediator)) goto out;
sleep_time *= 2;
} while (sleep_time < DISPATCH_CONTENTION_USLEEP_MAX);
_dispatch_debug("contention on global queue: %p", dq);
_dispatch_queue_wakeup_global(dq);
available = false;
out:
if (pending) {
(void)dispatch_atomic_dec2o(qc, dgq_pending, relaxed);
}
return available;
}
DISPATCH_ALWAYS_INLINE_NDEBUG
static inline struct dispatch_object_s *
_dispatch_queue_concurrent_drain_one(dispatch_queue_t dq)
{
struct dispatch_object_s *head, *next, *const mediator = (void *)~0ul;
start:
head = dispatch_atomic_xchg2o(dq, dq_items_head, mediator, relaxed);
if (slowpath(head == NULL)) {
(void)dispatch_atomic_cmpxchg2o(dq, dq_items_head, mediator, NULL,
relaxed);
_dispatch_root_queue_debug("no work on global queue: %p", dq);
return NULL;
}
if (slowpath(head == mediator)) {
if (fastpath(_dispatch_queue_concurrent_drain_one_slow(dq))) {
goto start;
}
return NULL;
}
next = fastpath(head->do_next);
if (slowpath(!next)) {
dispatch_atomic_store2o(dq, dq_items_head, NULL, relaxed);
if (dispatch_atomic_cmpxchg2o(dq, dq_items_tail, head, NULL, relaxed)) {
goto out;
}
while (!(next = head->do_next)) {
dispatch_hardware_pause();
}
}
dispatch_atomic_store2o(dq, dq_items_head, next, relaxed);
_dispatch_queue_wakeup_global(dq);
out:
return head;
}
static void
_dispatch_root_queue_drain(dispatch_queue_t dq)
{
#if DISPATCH_DEBUG
if (_dispatch_thread_getspecific(dispatch_queue_key)) {
DISPATCH_CRASH("Premature thread recycling");
}
#endif
_dispatch_thread_setspecific(dispatch_queue_key, dq);
#if DISPATCH_COCOA_COMPAT
if (dispatch_begin_thread_4GC) {
dispatch_begin_thread_4GC();
}
void *pool = _dispatch_autorelease_pool_push();
#endif // DISPATCH_COCOA_COMPAT
_dispatch_perfmon_start();
struct dispatch_object_s *item;
while ((item = fastpath(_dispatch_queue_concurrent_drain_one(dq)))) {
_dispatch_continuation_pop(item);
}
_dispatch_perfmon_end();
#if DISPATCH_COCOA_COMPAT
_dispatch_autorelease_pool_pop(pool);
if (dispatch_end_thread_4GC) {
dispatch_end_thread_4GC();
}
#endif // DISPATCH_COCOA_COMPAT
_dispatch_thread_setspecific(dispatch_queue_key, NULL);
}
#pragma mark -
#pragma mark dispatch_worker_thread
#if HAVE_PTHREAD_WORKQUEUES
static void
_dispatch_worker_thread3(void *context)
{
dispatch_queue_t dq = context;
dispatch_root_queue_context_t qc = dq->do_ctxt;
_dispatch_introspection_thread_add();
(void)dispatch_atomic_dec2o(qc, dgq_pending, relaxed);
_dispatch_root_queue_drain(dq);
__asm__("");
}
#if HAVE_PTHREAD_WORKQUEUE_SETDISPATCH_NP
static void
_dispatch_worker_thread2(int priority, int options,
void *context DISPATCH_UNUSED)
{
dispatch_assert(priority >= 0 && priority < WORKQ_NUM_PRIOQUEUE);
dispatch_assert(!(options & ~WORKQ_ADDTHREADS_OPTION_OVERCOMMIT));
dispatch_queue_t dq = _dispatch_wq2root_queues[priority][options];
return _dispatch_worker_thread3(dq);
}
#endif // HAVE_PTHREAD_WORKQUEUE_SETDISPATCH_NP
#endif // HAVE_PTHREAD_WORKQUEUES
#if DISPATCH_USE_PTHREAD_POOL
static void *
_dispatch_worker_thread(void *context)
{
dispatch_queue_t dq = context;
dispatch_root_queue_context_t qc = dq->do_ctxt;
dispatch_pthread_root_queue_context_t pqc = qc->dgq_ctxt;
if (pqc && pqc->dpq_thread_configure) {
pqc->dpq_thread_configure();
}
sigset_t mask;
int r;
r = sigfillset(&mask);
(void)dispatch_assume_zero(r);
r = _dispatch_pthread_sigmask(SIG_BLOCK, &mask, NULL);
(void)dispatch_assume_zero(r);
_dispatch_introspection_thread_add();
const int64_t timeout = (pqc ? 5ull : 65ull) * NSEC_PER_SEC;
do {
_dispatch_root_queue_drain(dq);
} while (dispatch_semaphore_wait(qc->dgq_thread_mediator,
dispatch_time(0, timeout)) == 0);
(void)dispatch_atomic_inc2o(qc, dgq_thread_pool_size, relaxed);
_dispatch_queue_wakeup_global(dq);
_dispatch_release(dq);
return NULL;
}
int
_dispatch_pthread_sigmask(int how, sigset_t *set, sigset_t *oset)
{
int r;
r = sigdelset(set, SIGILL);
(void)dispatch_assume_zero(r);
r = sigdelset(set, SIGTRAP);
(void)dispatch_assume_zero(r);
#if HAVE_DECL_SIGEMT
r = sigdelset(set, SIGEMT);
(void)dispatch_assume_zero(r);
#endif
r = sigdelset(set, SIGFPE);
(void)dispatch_assume_zero(r);
r = sigdelset(set, SIGBUS);
(void)dispatch_assume_zero(r);
r = sigdelset(set, SIGSEGV);
(void)dispatch_assume_zero(r);
r = sigdelset(set, SIGSYS);
(void)dispatch_assume_zero(r);
r = sigdelset(set, SIGPIPE);
(void)dispatch_assume_zero(r);
return pthread_sigmask(how, set, oset);
}
#endif // DISPATCH_USE_PTHREAD_POOL
#pragma mark -
#pragma mark dispatch_runloop_queue
static bool _dispatch_program_is_probably_callback_driven;
#if DISPATCH_COCOA_COMPAT
dispatch_queue_t
_dispatch_runloop_root_queue_create_4CF(const char *label, unsigned long flags)
{
dispatch_queue_t dq;
size_t dqs;
if (slowpath(flags)) {
return NULL;
}
dqs = sizeof(struct dispatch_queue_s) - DISPATCH_QUEUE_CACHELINE_PAD;
dq = _dispatch_alloc(DISPATCH_VTABLE(queue_runloop), dqs);
_dispatch_queue_init(dq);
dq->do_targetq = _dispatch_get_root_queue(0, true);
dq->dq_label = label ? label : "runloop-queue"; dq->do_suspend_cnt = DISPATCH_OBJECT_SUSPEND_LOCK;
dq->dq_running = 1;
dq->dq_is_thread_bound = 1;
_dispatch_runloop_queue_port_init(dq);
_dispatch_queue_set_bound_thread(dq);
_dispatch_object_debug(dq, "%s", __func__);
return _dispatch_introspection_queue_create(dq);
}
void
_dispatch_runloop_queue_xref_dispose(dispatch_queue_t dq)
{
_dispatch_object_debug(dq, "%s", __func__);
(void)dispatch_atomic_dec2o(dq, dq_running, relaxed);
unsigned int suspend_cnt = dispatch_atomic_sub2o(dq, do_suspend_cnt,
DISPATCH_OBJECT_SUSPEND_LOCK, release);
_dispatch_queue_clear_bound_thread(dq);
if (suspend_cnt == 0) {
_dispatch_wakeup(dq);
}
}
void
_dispatch_runloop_queue_dispose(dispatch_queue_t dq)
{
_dispatch_object_debug(dq, "%s", __func__);
_dispatch_introspection_queue_dispose(dq);
_dispatch_runloop_queue_port_dispose(dq);
_dispatch_queue_destroy(dq);
}
bool
_dispatch_runloop_root_queue_perform_4CF(dispatch_queue_t dq)
{
if (slowpath(dq->do_vtable != DISPATCH_VTABLE(queue_runloop))) {
DISPATCH_CLIENT_CRASH("Not a runloop queue");
}
dispatch_retain(dq);
bool r = _dispatch_runloop_queue_drain_one(dq);
dispatch_release(dq);
return r;
}
void
_dispatch_runloop_root_queue_wakeup_4CF(dispatch_queue_t dq)
{
if (slowpath(dq->do_vtable != DISPATCH_VTABLE(queue_runloop))) {
DISPATCH_CLIENT_CRASH("Not a runloop queue");
}
_dispatch_runloop_queue_probe(dq);
}
mach_port_t
_dispatch_runloop_root_queue_get_port_4CF(dispatch_queue_t dq)
{
if (slowpath(dq->do_vtable != DISPATCH_VTABLE(queue_runloop))) {
DISPATCH_CLIENT_CRASH("Not a runloop queue");
}
return (mach_port_t)dq->do_ctxt;
}
static void
_dispatch_runloop_queue_port_init(void *ctxt)
{
dispatch_queue_t dq = (dispatch_queue_t)ctxt;
mach_port_t mp;
kern_return_t kr;
_dispatch_safe_fork = false;
kr = mach_port_allocate(mach_task_self(), MACH_PORT_RIGHT_RECEIVE, &mp);
DISPATCH_VERIFY_MIG(kr);
(void)dispatch_assume_zero(kr);
kr = mach_port_insert_right(mach_task_self(), mp, mp,
MACH_MSG_TYPE_MAKE_SEND);
DISPATCH_VERIFY_MIG(kr);
(void)dispatch_assume_zero(kr);
if (dq != &_dispatch_main_q) {
struct mach_port_limits limits = {
.mpl_qlimit = 1,
};
kr = mach_port_set_attributes(mach_task_self(), mp,
MACH_PORT_LIMITS_INFO, (mach_port_info_t)&limits,
sizeof(limits));
DISPATCH_VERIFY_MIG(kr);
(void)dispatch_assume_zero(kr);
}
dq->do_ctxt = (void*)(uintptr_t)mp;
_dispatch_program_is_probably_callback_driven = true;
}
static void
_dispatch_runloop_queue_port_dispose(dispatch_queue_t dq)
{
mach_port_t mp = (mach_port_t)dq->do_ctxt;
if (!mp) {
return;
}
dq->do_ctxt = NULL;
kern_return_t kr = mach_port_deallocate(mach_task_self(), mp);
DISPATCH_VERIFY_MIG(kr);
(void)dispatch_assume_zero(kr);
kr = mach_port_mod_refs(mach_task_self(), mp, MACH_PORT_RIGHT_RECEIVE, -1);
DISPATCH_VERIFY_MIG(kr);
(void)dispatch_assume_zero(kr);
}
#pragma mark -
#pragma mark dispatch_main_queue
mach_port_t
_dispatch_get_main_queue_port_4CF(void)
{
dispatch_queue_t dq = &_dispatch_main_q;
dispatch_once_f(&_dispatch_main_q_port_pred, dq,
_dispatch_runloop_queue_port_init);
return (mach_port_t)dq->do_ctxt;
}
static bool main_q_is_draining;
DISPATCH_NOINLINE
static void
_dispatch_queue_set_mainq_drain_state(bool arg)
{
main_q_is_draining = arg;
}
void
_dispatch_main_queue_callback_4CF(mach_msg_header_t *msg DISPATCH_UNUSED)
{
if (main_q_is_draining) {
return;
}
_dispatch_queue_set_mainq_drain_state(true);
_dispatch_main_queue_drain();
_dispatch_queue_set_mainq_drain_state(false);
}
#endif
void
dispatch_main(void)
{
#if HAVE_PTHREAD_MAIN_NP
if (pthread_main_np()) {
#endif
_dispatch_object_debug(&_dispatch_main_q, "%s", __func__);
_dispatch_program_is_probably_callback_driven = true;
pthread_exit(NULL);
DISPATCH_CRASH("pthread_exit() returned");
#if HAVE_PTHREAD_MAIN_NP
}
DISPATCH_CLIENT_CRASH("dispatch_main() must be called on the main thread");
#endif
}
DISPATCH_NOINLINE DISPATCH_NORETURN
static void
_dispatch_sigsuspend(void)
{
static const sigset_t mask;
for (;;) {
sigsuspend(&mask);
}
}
DISPATCH_NORETURN
static void
_dispatch_sig_thread(void *ctxt DISPATCH_UNUSED)
{
_dispatch_clear_stack(0);
_dispatch_sigsuspend();
}
DISPATCH_NOINLINE
static void
_dispatch_queue_cleanup2(void)
{
dispatch_queue_t dq = &_dispatch_main_q;
(void)dispatch_atomic_dec2o(dq, dq_running, relaxed);
unsigned int suspend_cnt = dispatch_atomic_sub2o(dq, do_suspend_cnt,
DISPATCH_OBJECT_SUSPEND_LOCK, release);
dq->dq_is_thread_bound = 0;
if (suspend_cnt == 0) {
_dispatch_wakeup(dq);
}
if (_dispatch_program_is_probably_callback_driven) {
dispatch_async_f(_dispatch_get_root_queue(0, true), NULL,
_dispatch_sig_thread);
sleep(1); }
#if DISPATCH_COCOA_COMPAT
dispatch_once_f(&_dispatch_main_q_port_pred, dq,
_dispatch_runloop_queue_port_init);
_dispatch_runloop_queue_port_dispose(dq);
#endif
}
static void
_dispatch_queue_cleanup(void *ctxt)
{
if (ctxt == &_dispatch_main_q) {
return _dispatch_queue_cleanup2();
}
DISPATCH_CRASH("Premature thread exit while a dispatch queue is running");
}