Integrals w/o timestamp Partial specialization for integral types T and without clock. More...

#include <perfc/counter.hpp>

Detailed Description

template<class T>
class perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >

Integrals w/o timestamp Partial specialization for integral types T and without clock.

Represents a thread safe performance counter primitive of type T.

Note: This is the only Counter specialization that is completely lock-free on most architectures.

Satisfies AtomicCounter requirements.

Thread Safety: thread-safe – All operations are thread safe but not necessarily synchronized

Template Parameters

T	counter value type. Type requirements: `std::is_integral<T>::value == true`

Definition at line 140 of file counter.hpp.

Public Types
using	ClockType = void

using	TimePointType = void

using	ValueType = T

using	CounterType = std::atomic<T>

Public Member Functions
	Counter () noexcept
	Construct with value-initialized T (`T()`)

	Counter (T value) noexcept
	Construct with initial value value.

	Counter (Counter const &)=delete

bool	IsLockFree () const noexcept
	Query if operations are lock free.

void	Store (T value, MemoryOrder order=MemoryOrder::Release) noexcept
	Stores provided value in counter.

T	Load (MemoryOrder order=MemoryOrder::Acquire) const noexcept
	Load value from counter.

T	FetchAdd (T value, MemoryOrder order=MemoryOrder::Release) noexcept
	Perform post-increment with current value and value.

T	FetchSub (T value, MemoryOrder order=MemoryOrder::Release) noexcept
	Load value from counter.

T	operator++ () noexcept
	Pre-increment operator using default memory order.

T	operator++ (int) noexcept
	Post-increment operator using default memory order.

T	operator-- () noexcept
	Pre-decrement operator using default memory order.

T	operator-- (int) noexcept
	Post-decrement operator using default memory order.

T	operator+= (T value) noexcept
	Performs addition (equivalent to `FetchAdd(value) + value`

T	operator-= (T value) noexcept
	Performs subtraction (equivalent to `FetchSub(value) - value`

Static Public Attributes
static constexpr bool	IS_ALWAYS_LOCK_FREE = CounterType::is_always_lock_free
	Is true if counter is always lock free.

Related Symbols
(Note that these are not member symbols.)
enum	MemoryOrder
	Memory ordering constraints. More...

Member Typedef Documentation

◆ ClockType

template<class T>

using perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::ClockType = void

Definition at line 142 of file counter.hpp.

◆ CounterType

template<class T>

using perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::CounterType = std::atomic<T>

Definition at line 145 of file counter.hpp.

◆ TimePointType

template<class T>

using perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::TimePointType = void

Definition at line 143 of file counter.hpp.

◆ ValueType

template<class T>

using perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::ValueType = T

Definition at line 144 of file counter.hpp.

Constructor & Destructor Documentation

◆ Counter() [1/3]

template<class T>

perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::Counter ( )

inlineexplicitnoexcept

Construct with value-initialized T (T())

Definition at line 155 of file counter.hpp.

◆ Counter() [2/3]

template<class T>

perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::Counter ( T value )

inlineexplicitnoexcept

Construct with initial value value.

Parameters

value Initial value.

Definition at line 163 of file counter.hpp.

◆ Counter() [3/3]

template<class T>

perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::Counter ( Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type > const & )

delete

Member Function Documentation

◆ FetchAdd()

template<class T>

T perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::FetchAdd	(	T	value,
		MemoryOrder	order = MemoryOrder::Release )

inlinenoexcept

Perform post-increment with current value and value.

Parameters

value	value to add.
order	Memory order constraints.

Returns: Counter value immediately preceding the addition of value.

Definition at line 203 of file counter.hpp.

◆ FetchSub()

template<class T>

T perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::FetchSub	(	T	value,
		MemoryOrder	order = MemoryOrder::Release )

inlinenoexcept

Load value from counter.

Parameters

value	value to subtract.
order	Memory order constraints.

Returns: Counter value immediately preceding the addition of value.; Counter value.

Definition at line 215 of file counter.hpp.

◆ IsLockFree()

template<class T>

bool perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::IsLockFree ( ) const

inlinenoexcept

Query if operations are lock free.

Returns: true if operations are lock free.; false otherwise.

Definition at line 172 of file counter.hpp.

◆ Load()

template<class T>

T perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::Load ( MemoryOrder order = MemoryOrder::Acquire ) const

inlinenodiscardnoexcept

Load value from counter.

Parameters

order Memory order constraints.

Returns: Counter value.

Definition at line 192 of file counter.hpp.

◆ operator++() [1/2]

template<class T>

T perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::operator++ ( )

inlinenoexcept

Pre-increment operator using default memory order.

Definition at line 222 of file counter.hpp.

◆ operator++() [2/2]

template<class T>

T perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::operator++ ( int )

inlinenoexcept

Post-increment operator using default memory order.

Returns: Counter value before incrementation.

Definition at line 231 of file counter.hpp.

◆ operator+=()

template<class T>

T perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::operator+= ( T value )

inlinenoexcept

Performs addition (equivalent to FetchAdd(value) + value

Parameters

value value to add.

Returns: Result of arithmetic operation.

Definition at line 257 of file counter.hpp.

◆ operator--() [1/2]

template<class T>

T perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::operator-- ( )

inlinenoexcept

Pre-decrement operator using default memory order.

Definition at line 238 of file counter.hpp.

◆ operator--() [2/2]

template<class T>

T perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::operator-- ( int )

inlinenoexcept

Post-decrement operator using default memory order.

Returns: Counter value before decrementation.

Definition at line 247 of file counter.hpp.

◆ operator-=()

template<class T>

T perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::operator-= ( T value )

inlinenoexcept

Performs subtraction (equivalent to FetchSub(value) - value

Parameters

value value to subtract.

Returns: Result of arithmetic operation.

Definition at line 267 of file counter.hpp.

◆ Store()

template<class T>

void perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::Store	(	T	value,
		MemoryOrder	order = MemoryOrder::Release )

inlinenoexcept

Stores provided value in counter.

Parameters

value	Counter value to store.
order	Memory order constraints.

Definition at line 182 of file counter.hpp.

Friends And Related Symbol Documentation

◆ MemoryOrder

enum MemoryOrder : std::underlying_type_t< std::memory_order >

Memory ordering constraints.

Definition at line 81 of file counter.hpp.

Member Data Documentation

◆ IS_ALWAYS_LOCK_FREE

template<class T>

bool perfc::Counter< T, void, typename std::enable_if< std::is_integral< T >::value >::type >::IS_ALWAYS_LOCK_FREE = CounterType::is_always_lock_free

staticconstexpr

Is true if counter is always lock free.

Definition at line 150 of file counter.hpp.

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

perfc/src/include/perfc/counter.hpp

Detailed Description

Public Types

Public Member Functions

Static Public Attributes

Related Symbols

Member Typedef Documentation

◆ ClockType

◆ CounterType

◆ TimePointType

◆ ValueType

Constructor & Destructor Documentation

◆ Counter() [1/3]

◆ Counter() [2/3]

◆ Counter() [3/3]

Member Function Documentation

◆ FetchAdd()

◆ FetchSub()

◆ IsLockFree()

◆ Load()

◆ operator++() [1/2]

◆ operator++() [2/2]

◆ operator+=()

◆ operator--() [1/2]

◆ operator--() [2/2]

◆ operator-=()

◆ Store()

Friends And Related Symbol Documentation

◆ MemoryOrder

Member Data Documentation

◆ IS_ALWAYS_LOCK_FREE