tbb::internal::task_proxy Struct Reference

#include <mailbox.h>

Inheritance diagram for tbb::internal::task_proxy:

Collaboration diagram for tbb::internal::task_proxy:

Public Member Functions
template<intptr_t from_bit>
task *	extract_task ()
	Returns a pointer to the encapsulated task or NULL, and frees proxy if necessary. More...
Public Member Functions inherited from tbb::task
virtual	~task ()
	Destructor. More...
virtual task *	execute ()=0
	Should be overridden by derived classes. More...
internal::allocate_continuation_proxy &	allocate_continuation ()
	Returns proxy for overloaded new that allocates a continuation task of *this. More...
internal::allocate_child_proxy &	allocate_child ()
	Returns proxy for overloaded new that allocates a child task of *this. More...
void	recycle_as_continuation ()
	Change this to be a continuation of its former self. More...
void	recycle_as_safe_continuation ()
	Recommended to use, safe variant of recycle_as_continuation. More...
void	recycle_as_child_of (task &new_parent)
	Change this to be a child of new_parent. More...
void	recycle_to_reexecute ()
	Schedule this for reexecution after current execute() returns. More...
void	set_ref_count (int count)
	Set reference count. More...
void	increment_ref_count ()
	Atomically increment reference count. More...
int	add_ref_count (int count)
	Atomically adds to reference count and returns its new value. More...
int	decrement_ref_count ()
	Atomically decrement reference count and returns its new value. More...
void	spawn_and_wait_for_all (task &child)
	Similar to spawn followed by wait_for_all, but more efficient. More...
void __TBB_EXPORTED_METHOD	spawn_and_wait_for_all (task_list &list)
	Similar to spawn followed by wait_for_all, but more efficient. More...
void	wait_for_all ()
	Wait for reference count to become one, and set reference count to zero. More...
task *	parent () const
	task on whose behalf this task is working, or NULL if this is a root. More...
void	set_parent (task *p)
	sets parent task pointer to specified value More...
task_group_context *	context ()
	This method is deprecated and will be removed in the future. More...
task_group_context *	group ()
	Pointer to the task group descriptor. More...
bool	is_stolen_task () const
	True if task was stolen from the task pool of another thread. More...
bool	is_enqueued_task () const
	True if the task was enqueued. More...
state_type	state () const
	Current execution state. More...
int	ref_count () const
	The internal reference count. More...
bool __TBB_EXPORTED_METHOD	is_owned_by_current_thread () const
	Obsolete, and only retained for the sake of backward compatibility. Always returns true. More...
void	set_affinity (affinity_id id)
	Set affinity for this task. More...
affinity_id	affinity () const
	Current affinity of this task. More...
virtual void __TBB_EXPORTED_METHOD	note_affinity (affinity_id id)
	Invoked by scheduler to notify task that it ran on unexpected thread. More...
void __TBB_EXPORTED_METHOD	change_group (task_group_context &ctx)
	Moves this task from its current group into another one. More...
bool	cancel_group_execution ()
	Initiates cancellation of all tasks in this cancellation group and its subordinate groups. More...
bool	is_cancelled () const
	Returns true if the context has received cancellation request. More...
__TBB_DEPRECATED void	set_group_priority (priority_t p)
	Changes priority of the task group this task belongs to. More...
__TBB_DEPRECATED priority_t	group_priority () const
	Retrieves current priority of the task group this task belongs to. More...

Static Public Member Functions
static bool	is_shared (intptr_t tat)
	True if the proxy is stored both in its sender's pool and in the destination mailbox. More...
static task *	task_ptr (intptr_t tat)
	Returns a pointer to the encapsulated task or NULL. More...
Static Public Member Functions inherited from tbb::task
static internal::allocate_root_proxy	allocate_root ()
	Returns proxy for overloaded new that allocates a root task. More...
static internal::allocate_root_with_context_proxy	allocate_root (task_group_context &ctx)
	Returns proxy for overloaded new that allocates a root task associated with user supplied context. More...
static void	spawn_root_and_wait (task &root)
	Spawn task allocated by allocate_root, wait for it to complete, and deallocate it. More...
static void	spawn_root_and_wait (task_list &root_list)
	Spawn root tasks on list and wait for all of them to finish. More...
static void	enqueue (task &t)
	Enqueue task for starvation-resistant execution. More...
static void	enqueue (task &t, priority_t p)
	Enqueue task for starvation-resistant execution on the specified priority level. More...
static void	enqueue (task &t, task_arena &arena, priority_t p=priority_t(0))
	Enqueue task in task_arena. More...
static task &__TBB_EXPORTED_FUNC	self ()
	The innermost task being executed or destroyed by the current thread at the moment. More...

Public Attributes
intptr_t	task_and_tag
task_proxy *__TBB_atomic	next_in_mailbox
	Pointer to next task_proxy in a mailbox. More...
mail_outbox *	outbox
	Mailbox to which this was mailed. More...

Static Public Attributes
static const intptr_t	pool_bit = 1<<0
static const intptr_t	mailbox_bit = 1<<1
static const intptr_t	location_mask = pool_bit | mailbox_bit

Additional Inherited Members
Public Types inherited from tbb::task
enum	state_type {   executing, reexecute, ready, allocated,   freed, recycle }
	Enumeration of task states that the scheduler considers. More...
typedef internal::affinity_id	affinity_id
	An id as used for specifying affinity. More...
Protected Member Functions inherited from tbb::task
	task ()
	Default constructor. More...

Detailed Description

Definition at line 29 of file mailbox.h.

Member Function Documentation

extract_task()

template<intptr_t from_bit>

task* tbb::internal::task_proxy::extract_task ( )

inline

Returns a pointer to the encapsulated task or NULL, and frees proxy if necessary.

Definition at line 57 of file mailbox.h.

                                 {
        __TBB_ASSERT( prefix().extra_state == es_task_proxy, "Normal task misinterpreted as a proxy?" );
        intptr_t tat = __TBB_load_with_acquire(task_and_tag);
        __TBB_ASSERT( tat == from_bit || (is_shared(tat) && task_ptr(tat)),
            "Proxy's tag cannot specify both locations if the proxy "
            "was retrieved from one of its original locations" );
        if ( tat != from_bit ) {
            const intptr_t cleaner_bit = location_mask & ~from_bit;
            // Attempt to transition the proxy to the "empty" state with
            // cleaner_bit specifying entity responsible for its eventual freeing.
            // Explicit cast to void* is to work around a seeming ICC 11.1 bug.
            if ( as_atomic(task_and_tag).compare_and_swap(cleaner_bit, tat) == tat ) {
                // Successfully grabbed the task, and left new owner with the job of freeing the proxy
                return task_ptr(tat);
            }
        }
        // Proxied task has already been claimed from another proxy location.
        __TBB_ASSERT( task_and_tag == from_bit, "Empty proxy cannot contain non-zero task pointer" );
        return NULL;
    }

References __TBB_ASSERT, tbb::internal::__TBB_load_with_acquire(), tbb::internal::as_atomic(), tbb::internal::es_task_proxy, is_shared(), location_mask, tbb::task::prefix(), task_and_tag, and task_ptr().

Referenced by tbb::internal::generic_scheduler::get_task(), and tbb::internal::generic_scheduler::steal_task().

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is_shared()

static bool tbb::internal::task_proxy::is_shared ( intptr_t  tat )

inlinestatic

True if the proxy is stored both in its sender's pool and in the destination mailbox.

Definition at line 46 of file mailbox.h.

                                           {
        return (tat & location_mask) == location_mask;
    }

References location_mask.

Referenced by extract_task(), and tbb::internal::generic_scheduler::steal_task_from().

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task_ptr()

static task* tbb::internal::task_proxy::task_ptr ( intptr_t  tat )

inlinestatic

Returns a pointer to the encapsulated task or NULL.

Definition at line 51 of file mailbox.h.

                                           {
        return (task*)(tat & ~location_mask);
    }

References location_mask.

Referenced by extract_task().

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Member Data Documentation

location_mask

const intptr_t tbb::internal::task_proxy::location_mask = pool_bit | mailbox_bit

static

Definition at line 32 of file mailbox.h.

Referenced by extract_task(), is_shared(), tbb::internal::generic_scheduler::prepare_for_spawning(), and task_ptr().

mailbox_bit

const intptr_t tbb::internal::task_proxy::mailbox_bit = 1<<1

static

Definition at line 31 of file mailbox.h.

Referenced by tbb::internal::generic_scheduler::get_mailbox_task().

next_in_mailbox

task_proxy* __TBB_atomic tbb::internal::task_proxy::next_in_mailbox

Pointer to next task_proxy in a mailbox.

Definition at line 40 of file mailbox.h.

Referenced by tbb::internal::mail_outbox::drain(), tbb::internal::mail_outbox::internal_pop(), and tbb::internal::mail_outbox::push().

outbox

mail_outbox* tbb::internal::task_proxy::outbox

Mailbox to which this was mailed.

Definition at line 43 of file mailbox.h.

Referenced by tbb::internal::generic_scheduler::prepare_for_spawning(), and tbb::internal::generic_scheduler::steal_task_from().

pool_bit

const intptr_t tbb::internal::task_proxy::pool_bit = 1<<0

static

Definition at line 30 of file mailbox.h.

Referenced by tbb::internal::generic_scheduler::get_task(), and tbb::internal::generic_scheduler::steal_task().

task_and_tag

intptr_t tbb::internal::task_proxy::task_and_tag

Definition at line 37 of file mailbox.h.

Referenced by extract_task(), tbb::internal::generic_scheduler::prepare_for_spawning(), and tbb::internal::generic_scheduler::steal_task_from().

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The documentation for this struct was generated from the following file:

• mailbox.h