A token to hold the scope of an ArrayHandle or other object.
A Token is an object that is held in the stack or state of another object and is used when creating references to resouces that may be used by other threads. For example, when preparing an ArrayHandle or ExecutionObject for a device, a Token is given. The returned object will be valid as long as the Token remains in scope.
template<typename T >
| void vtkm::cont::Token::Attach |
( |
T && |
object, |
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vtkm::cont::Token::ReferenceCount * |
referenceCountPoiner, |
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std::mutex * |
mutexPointer, |
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std::condition_variable * |
conditionVariablePointer |
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) |
| |
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inline |
Add an object to attach to the Token.
To attach an object to a Token, you need the object itself, a pointer to a Token::ReferenceCount that is used to count how many Tokens hold the object, a pointer to a std::mutex used to safely use the ReferenceCount, and a pointer to a std::condition_variable that other threads will wait on if they are blocked by the Token (using the same mutex in the given unique_lock). The mutex can also be passed in as a std::unique_lock<std::mutex> to signal whether or not the mutex is already locked by the current thread.
When the Token is attached, it will increment the reference count (safely with the mutex) and store away these items. Other items will be able tell if a token is attached to the object by looking at the reference count.
When the Token is released, it will decrement the reference count (safely with the mutex) and then notify all threads waiting on the condition variable.
template<typename T >
| void vtkm::cont::Token::Attach |
( |
T && |
object, |
|
|
vtkm::cont::Token::ReferenceCount * |
referenceCountPointer, |
|
|
std::unique_lock< std::mutex > & |
lock, |
|
|
std::condition_variable * |
conditionVariablePointer |
|
) |
| |
|
inline |
Add an object to attach to the Token.
To attach an object to a Token, you need the object itself, a pointer to a Token::ReferenceCount that is used to count how many Tokens hold the object, a pointer to a std::mutex used to safely use the ReferenceCount, and a pointer to a std::condition_variable that other threads will wait on if they are blocked by the Token (using the same mutex in the given unique_lock). The mutex can also be passed in as a std::unique_lock<std::mutex> to signal whether or not the mutex is already locked by the current thread.
When the Token is attached, it will increment the reference count (safely with the mutex) and store away these items. Other items will be able tell if a token is attached to the object by looking at the reference count.
When the Token is released, it will decrement the reference count (safely with the mutex) and then notify all threads waiting on the condition variable.
