mysql::concurrency::Spin_lock_mutex Class Reference

Implementation of a spin-lock mutex. More...

#include <spin_lock_mutex.h>

Public Member Functions
	Spin_lock_mutex (const Spin_lock_mutex &)=delete
	Spin_lock_mutex (Spin_lock_mutex &&)=delete
Spin_lock_mutex &	operator= (const Spin_lock_mutex &src)=delete
Spin_lock_mutex &	operator= (Spin_lock_mutex &&src)=delete
	Spin_lock_mutex (Mutex_key key={})
	~Spin_lock_mutex ()=default
void	lock () noexcept
	Acquire a lock, blocks access to a critical section until "unlock" is called. More...
bool	try_lock () noexcept
	Non-blocking try-lock operation. More...
void	unlock ()
	Unblocks access to a critical section for other threads. More...

Static Private Member Functions
static void	spin_yield () noexcept

Private Attributes
std::atomic_flag	m_lock = ATOMIC_FLAG_INIT
	Internal synchronization boolean, true means that lock is currently owned Since C++20, default constructor sets atomic_flag to "clear" state We use atomic_flag because it is guaranteed to be lock free. More...

Detailed Description

Implementation of a spin-lock mutex.

Satisfies requirements of Mutex

• Lockable
• DefaultConstructible
• Destructible
• not copyable
• not movable

  Note

  Use with care. In general, is not recommended to use spin locks over mutexes. Spin locks should be used only when expected contention is minimal (e.g. when combining with strip-locking techniques).

Constructor & Destructor Documentation

Spin_lock_mutex() [1/3]

mysql::concurrency::Spin_lock_mutex::Spin_lock_mutex ( const Spin_lock_mutex &  )

delete

Spin_lock_mutex() [2/3]

mysql::concurrency::Spin_lock_mutex::Spin_lock_mutex ( Spin_lock_mutex &&  )

delete

Spin_lock_mutex() [3/3]

mysql::concurrency::Spin_lock_mutex::Spin_lock_mutex ( Mutex_key  key = {} )

inline

~Spin_lock_mutex()

mysql::concurrency::Spin_lock_mutex::~Spin_lock_mutex ( )

default

Member Function Documentation

lock()

void mysql::concurrency::Spin_lock_mutex::lock ( )

noexcept

Acquire a lock, blocks access to a critical section until "unlock" is called.

operator=() [1/2]

Spin_lock_mutex & mysql::concurrency::Spin_lock_mutex::operator= ( const Spin_lock_mutex &  src )

delete

operator=() [2/2]

Spin_lock_mutex & mysql::concurrency::Spin_lock_mutex::operator= ( Spin_lock_mutex &&  src )

delete

spin_yield()

static void mysql::concurrency::Spin_lock_mutex::spin_yield ( )

inlinestaticprivatenoexcept

try_lock()

bool mysql::concurrency::Spin_lock_mutex::try_lock ( )

noexcept

Non-blocking try-lock operation.

Return values

true	Lock has been acquired
false	Lock has NOT been acquired

unlock()

void mysql::concurrency::Spin_lock_mutex::unlock

(

)

Unblocks access to a critical section for other threads.

Member Data Documentation

m_lock

std::atomic_flag mysql::concurrency::Spin_lock_mutex::m_lock = ATOMIC_FLAG_INIT

private

Internal synchronization boolean, true means that lock is currently owned Since C++20, default constructor sets atomic_flag to "clear" state We use atomic_flag because it is guaranteed to be lock free.

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

• libs/mysql/concurrency/spin_lock_mutex.h
• libs/mysql/concurrency/spin_lock_mutex.cpp