rav::AtomicRwLock Class Reference

A lock-free (and sometimes wait-free) reader writer lock. More...

#include <atomic_rw_lock.hpp>

Classes
struct	Exclusive
	Exclusive unlock function. More...
struct	Shared
	Shared unlock function. More...
struct	AccessGuard
	Guards access to a critical region. More...

Public Member Functions
AccessGuard< Exclusive >	lock_exclusive ()
	Attempts to acquire an exclusive lock, spinning util it succeeds, or until the loop upper bounds is reached.
AccessGuard< Exclusive >	try_lock_exclusive ()
	Attempts to acquire an exclusive lock.
AccessGuard< Shared >	lock_shared ()
	Attempts to acquire a shared lock, spinning util it succeeds, or until the loop upper bounds is reached.
AccessGuard< Shared >	try_lock_shared ()
	Attempts to acquire a shared lock.
bool	is_locked_shared () const
bool	is_locked_exclusively () const
bool	is_locked () const

Static Public Attributes
static constexpr size_t	k_loop_upper_bound = 1'000'000
	The max number of tries before giving up (preventing runaway code).
static constexpr uint32_t	k_yield_threshold = 10
	The number of iterations after which a function will start yielding.
static constexpr uint32_t	k_sleep_threshold = 10'000
	The number of iterations after which a function will start sleeping.

Detailed Description

A lock-free (and sometimes wait-free) reader writer lock.

Definition at line 37 of file atomic_rw_lock.hpp.

Member Function Documentation

is_locked()

bool rav::AtomicRwLock::is_locked ( ) const

inlinenodiscard

Returns

True if locked shared or exclusively. This is a relaxed check and cannot be used to draw any conclusions.

Definition at line 204 of file atomic_rw_lock.hpp.

is_locked_exclusively()

bool rav::AtomicRwLock::is_locked_exclusively ( ) const

inlinenodiscard

Returns

True if locked exclusively. This is a relaxed check and cannot be used to draw any conclusions.

Definition at line 197 of file atomic_rw_lock.hpp.

is_locked_shared()

bool rav::AtomicRwLock::is_locked_shared ( ) const

inlinenodiscard

Returns

True if shared locked. This is a relaxed check and cannot be used to draw any conclusions.

Definition at line 190 of file atomic_rw_lock.hpp.

lock_exclusive()

AccessGuard< Exclusive > rav::AtomicRwLock::lock_exclusive ( )

inlinenodiscard

Attempts to acquire an exclusive lock, spinning util it succeeds, or until the loop upper bounds is reached.

Thread safe: yes Wait-free: no

Returns

A guard which holds on to the lock as long as it's alive. Check for validity before using.

Definition at line 100 of file atomic_rw_lock.hpp.

lock_shared()

AccessGuard< Shared > rav::AtomicRwLock::lock_shared ( )

inlinenodiscard

Attempts to acquire a shared lock, spinning util it succeeds, or until the loop upper bounds is reached.

Thread safe: yes Wait-free: no

Returns

A guard which holds on to the lock as long as it's alive. Check for validity before using.

Definition at line 148 of file atomic_rw_lock.hpp.

try_lock_exclusive()

AccessGuard< Exclusive > rav::AtomicRwLock::try_lock_exclusive ( )

inlinenodiscard

Attempts to acquire an exclusive lock.

Note: this call can fail if a reader is trying to get access at the same time. Thread safe: yes Wait-free: yes

Returns

A guard which holds on to the lock as long as it's alive. Check for validity before using.

Definition at line 134 of file atomic_rw_lock.hpp.

try_lock_shared()

AccessGuard< Shared > rav::AtomicRwLock::try_lock_shared ( )

inlinenodiscard

Attempts to acquire a shared lock.

This will always succeed when there is no exclusive lock. This call will always succeed if there are no writers (waiting). Thread safe: yes Wait-free: yes

Returns

A guard which holds on to the lock as long as it's alive. Check for validity before using.

Definition at line 171 of file atomic_rw_lock.hpp.

Member Data Documentation

k_loop_upper_bound

size_t rav::AtomicRwLock::k_loop_upper_bound = 1'000'000

staticconstexpr

The max number of tries before giving up (preventing runaway code).

Definition at line 40 of file atomic_rw_lock.hpp.

k_sleep_threshold

uint32_t rav::AtomicRwLock::k_sleep_threshold = 10'000

staticconstexpr

The number of iterations after which a function will start sleeping.

Definition at line 46 of file atomic_rw_lock.hpp.

k_yield_threshold

uint32_t rav::AtomicRwLock::k_yield_threshold = 10

staticconstexpr

The number of iterations after which a function will start yielding.

Definition at line 43 of file atomic_rw_lock.hpp.

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

• atomic_rw_lock.hpp