std::atomic_flag

 

C++

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Expresiones biblioteca Regular (C++11)

Operaciones de biblioteca Atómica (C++11)

Tema Biblioteca de ayuda (C++11)

 

Operaciones de biblioteca Atómica

Tipos Original: Types The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

atomic (C++11)

atomic_is_lock_free (C++11)

Funciones Original: Functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

atomic_store atomic_store_explicit (C++11) (C++11)

atomic_load atomic_load_explicit (C++11) (C++11)

atomic_exchange atomic_exchange_explicit (C++11) (C++11)

atomic_compare_exchange_weak atomic_compare_exchange_weak_explicit atomic_compare_exchange_strong atomic_compare_exchange_strong_explicit (C++11) (C++11) (C++11) (C++11)

atomic_fetch_add atomic_fetch_add_explicit (C++11) (C++11)

atomic_fetch_sub atomic_fetch_sub_explicit (C++11) (C++11)

atomic_fetch_and atomic_fetch_and_explicit (C++11) (C++11)

atomic_fetch_or atomic_fetch_or_explicit (C++11) (C++11)

atomic_fetch_xor atomic_fetch_xor_explicit (C++11) (C++11)

Banderas atómicas Original: Atomic flags The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

atomic_flag (C++11)

atomic_flag_test_and_set atomic_flag_test_and_set_explicit (C++11) (C++11)

atomic_flag_clear atomic_flag_clear_explicit (C++11) (C++11)

Inicialización Original: Initialization The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

atomic_init (C++11)

ATOMIC_VAR_INIT (C++11)

ATOMIC_FLAG_INIT (C++11)

Memoria pedido Original: Memory ordering The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

memory_order (C++11)

kill_dependency (C++11)

atomic_thread_fence (C++11)

atomic_signal_fence (C++11)

 

std::atomic_flag

Las funciones miembro Original: Member functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

atomic_flag::atomic_flag

atomic_flag::operator=

atomic_flag::clear

atomic_flag::test_and_set

 

Defined in header <atomic>
class atomic_flag;		(ya que C + +11)

std::atomic_flag es un tipo booleano atómico. A diferencia de todas las especialidades de std::atomic, se garantiza que sea sin bloqueo. A diferencia de std::atomic<bool>, std::atomic_flag no proporciona carga o de operaciones de la tienda .

Original:

std::atomic_flag is an atomic boolean type. Unlike all specializations of std::atomic, it is guaranteed to be lock-free. Unlike std::atomic<bool>, std::atomic_flag does not provide load or store operations.

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Las funciones miembro

(constructor)	construye un atomic_flag Original: constructs an atomic_flag The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (miembro público función)
operator=	el operador de asignación Original: the assignment operator The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (miembro público función)
clear	atómicamente establece el marcador a false Original: atomically sets flag to false The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (miembro público función)
test_and_set	atómicamente establece el indicador true y obtiene su valor anterior Original: atomically sets the flag to true and obtains its previous value The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (miembro público función)

Ejemplo

Un mutex spinlock puede ser implementado en el espacio de usuario utilizando un atomic_flag

Original:

A spinlock mutex can be implemented in userspace using an atomic_flag

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#include <thread>
#include <vector>
#include <iostream>
#include <atomic>
 
std::atomic_flag lock = ATOMIC_FLAG_INIT;
 
void f(int n)
{
    for(int cnt = 0; cnt < 100; ++cnt) {
        while(lock.test_and_set(std::memory_order_acquire))  // acquire lock
             ; // spin
        std::cout << "Output from thread " << n << '\n';
        lock.clear(std::memory_order_release);               // release lock
    }
}
int main()
{
    std::vector<std::thread> v;
    for (int n = 0; n < 10; ++n) {
        v.emplace_back(f, n);
    }
    for (auto& t : v) {
        t.join();
    }
}

Output:

Output from thread 2
Output from thread 6
Output from thread 7
...<exactly 1000 lines>...

Ver también

atomic_flag_test_and_set atomic_flag_test_and_set_explicit (C++11) (C++11)	atómicamente establece el indicador a true y devuelve su valor anterior Original: atomically sets the flag to true and returns its previous value The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (función)
atomic_flag_clear atomic_flag_clear_explicit (C++11) (C++11)	atómicamente establece el valor de la bandera de false Original: atomically sets the value of the flag to false The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (función)
ATOMIC_FLAG_INIT (C++11)	initializes an std::atomic_flag to false (macro constante)
C documentation for atomic_flag