16 #ifndef dealii_thread_management_h
17 #define dealii_thread_management_h
37 #ifdef DEAL_II_HAVE_CXX20
42 #ifdef DEAL_II_WITH_TBB
43 # include <tbb/task_group.h>
76 template <
typename ForwardIterator>
77 std::vector<std::pair<ForwardIterator, ForwardIterator>>
79 const ForwardIterator &
end,
80 const unsigned int n_intervals);
90 std::vector<std::pair<unsigned int, unsigned int>>
92 const unsigned int end,
93 const unsigned int n_intervals);
145 template <
typename ForwardIterator>
146 std::vector<std::pair<ForwardIterator, ForwardIterator>>
148 const ForwardIterator &
end,
149 const unsigned int n_intervals)
151 using IteratorPair = std::pair<ForwardIterator, ForwardIterator>;
157 if (n_intervals == 1)
158 return (std::vector<IteratorPair>(1, IteratorPair(
begin,
end)));
161 const unsigned int n_elements = std::distance(
begin,
end);
162 const unsigned int n_elements_per_interval = n_elements / n_intervals;
163 const unsigned int residual = n_elements % n_intervals;
165 std::vector<IteratorPair> return_values(n_intervals);
167 return_values[0].first =
begin;
168 for (
unsigned int i = 0; i < n_intervals; ++i)
170 if (i != n_intervals - 1)
172 return_values[i].second = return_values[i].first;
178 static_cast<signed int>(n_elements_per_interval));
182 ++return_values[i].second;
184 return_values[i + 1].first = return_values[i].second;
187 return_values[i].second =
end;
189 return return_values;
217 template <
typename RT>
238 "You cannot read the return value of a thread or task "
239 "if that value has not been set. This happens, for example, if "
240 "a task or thread threw an exception."));
247 value = std::move(v);
262 value = std::move(v.get());
287 template <
typename RT>
299 , value_is_initialized(false)
302 inline reference_type
306 value_is_initialized,
308 "You cannot read the return value of a thread or task "
309 "if that value has not been set. This happens, for example, if "
310 "a task or thread threw an exception."));
333 value_is_initialized =
true;
389 template <
typename T>
408 template <
typename T>
411 static std::reference_wrapper<T>
426 template <
typename RT,
typename Function>
428 (std::invocable<Function> &&
429 std::convertible_to<std::invoke_result_t<Function>, RT>))
432 promise.set_value(
function());
445 template <
typename Function>
448 std::promise<
void> &promise)
483 template <
typename RT =
void>
498 Task(
const std::function<RT()> &function_object)
502 #ifdef DEAL_II_WITH_TBB
507 std::unique_ptr<std::promise<RT>> promise =
508 std::make_unique<std::promise<RT>>();
510 std::make_shared<TaskData>(std::move(promise->get_future()));
550 std::shared_ptr<std::promise<RT>>(std::move(promise))]() {
560 promise->set_exception(std::current_exception());
589 std::async(std::launch::async | std::launch::deferred,
605 std::promise<RT> promise;
606 task_data = std::make_shared<TaskData>(promise.get_future());
616 promise.set_exception(std::current_exception());
766 "The current object is not associated with a task that "
767 "can be joined. It may have been detached, or you "
768 "may have already joined it in the past.");
873 std::lock_guard<std::mutex> lock(
mutex);
878 #ifdef DEAL_II_WITH_TBB
973 #ifdef DEAL_II_WITH_TBB
979 friend class Task<RT>;
1011 template <
typename RT>
1097 template <
typename FunctionObjectType>
1099 inline auto
new_task(FunctionObjectType function_object)
1100 ->
Task<decltype(function_object())>
1102 using return_type = decltype(function_object());
1104 return new_task(std::function<return_type()>(function_object));
1115 template <
typename RT,
typename... Args>
1121 [dummy, fun_ptr]() -> RT {
return std::apply(fun_ptr, dummy); });
1132 template <
typename RT,
typename C,
typename... Args>
1139 return new_task(std::function<RT()>(std::bind(
1149 template <
typename RT,
typename C,
typename... Args>
1156 return new_task(std::function<RT()>(std::bind(
1175 template <
typename RT =
void>
1200 return tasks.size();
1220 std::vector<RT> results;
1221 results.reserve(
size());
1222 for (
auto &t :
tasks)
1223 results.emplace_back(std::move(t.return_value()));
1237 for (
auto &t :
tasks)
static void initialize_multithreading()
static unsigned int n_threads()
std::list< Task< RT > > tasks
std::vector< RT > return_values()
TaskGroup & operator+=(const Task< RT > &t)
TaskData(std::future< RT > &&future) noexcept
TaskData(const TaskData &)=delete
std::atomic< bool > task_has_finished
internal::return_value< RT > returned_object
TaskData & operator=(const TaskData &)=delete
TaskData(TaskData &&)=delete
TaskData & operator=(TaskData &&)=delete
internal::return_value< RT >::reference_type get()
tbb::task_group task_group
std::shared_ptr< TaskData > task_data
internal::return_value< RT >::reference_type return_value()
Task(const std::function< RT()> &function_object)
#define DEAL_II_NAMESPACE_OPEN
#define DEAL_II_CXX20_REQUIRES(condition)
#define DEAL_II_NAMESPACE_CLOSE
static ::ExceptionBase & ExcNoTask()
#define Assert(cond, exc)
#define DeclExceptionMsg(Exception, defaulttext)
static ::ExceptionBase & ExcMessage(std::string arg1)
#define AssertThrow(cond, exc)
std::vector< std::pair< unsigned int, unsigned int > > split_interval(const unsigned int begin, const unsigned int end, const unsigned int n_intervals)
std::vector< std::pair< ForwardIterator, ForwardIterator > > split_range(const ForwardIterator &begin, const ForwardIterator &end, const unsigned int n_intervals)
Task< RT > new_task(const std::function< RT()> &function)
void apply(const Kokkos::TeamPolicy< MemorySpace::Default::kokkos_space::execution_space >::member_type &team_member, const Kokkos::View< Number *, MemorySpace::Default::kokkos_space > shape_data, const ViewTypeIn in, ViewTypeOut out)
SymmetricTensor< 2, dim, Number > C(const Tensor< 2, dim, Number > &F)
void handle_unknown_exception()
void evaluate_and_set_promise(Function &function, std::promise< RT > &promise)
void handle_std_exception(const std::exception &exc)
VectorType::value_type * begin(VectorType &V)
VectorType::value_type * end(VectorType &V)
typename type_identity< T >::type type_identity_t
static std::reference_wrapper< T > act(T &t)
reference_type get() const
bool value_is_initialized
void set_from(std::future< RT & > &v)
void set_from(std::future< void > &)
bool value_is_initialized
void set_from(std::future< RT > &v)
void advance(std::tuple< I1, I2 > &t, const unsigned int n)