Base object class for RCU-style synchronization for Athena. More...

#include <RCUObject.h>

Inheritance diagram for Athena::IRCUObject:

Collaboration diagram for Athena::IRCUObject:

Public Types
enum	NoObjectEnum { NoObject }
	Value to pass to a constructor to mark that we shouldn't allocate an object. More...

Public Member Functions
	IRCUObject (IRCUSvc &svc)
	Constructor, with RCUSvc.
	IRCUObject (size_t nslots)
	Constructor, with event slot count.
	IRCUObject (IRCUObject &&other)
	Move constructor.
	IRCUObject (const IRCUObject &)=delete
IRCUObject &	operator= (const IRCUObject &)=delete
IRCUObject &	operator= (IRCUObject &&)=delete
virtual	~IRCUObject ()
	Destructor.
void	quiescent ()
	Declare the current event slot of this object to be quiescent.
void	quiescent (const EventContext &ctx)
	Declare the event slot `ctx` of this object to be quiescent.

Protected Types
typedef std::mutex	mutex_t
typedef std::unique_lock< mutex_t >	lock_t

Protected Member Functions
bool	endGrace (lock_t &lock, const EventContext &ctx)
	Declare that the grace period for a slot is ending.
void	setGrace (lock_t &)
	Declare that all slots are in a grace period.
mutex_t &	mutex ()
	Return the mutex for this object.
virtual void	clearAll (lock_t &)=0
	Delete all objects.
virtual bool	clearOld (lock_t &, size_t nold)=0
	Delete old objects.
void	makeOld (lock_t &lock, size_t garbageSize)
	Make existing pending objects old, if possible.

Private Member Functions
void	quiescentOol (const EventContext &ctx)
	Out-of-line part of quiescent().

Private Attributes
std::mutex	m_mutex
	The mutex for this object.
IRCUSvc *	m_svc
	The service with which we're registered, or null.
std::unique_ptr< RCUObjectGraceSets >	m_graceSets
	Holds the current and old grace period bitmasks.
size_t	m_nold
	Number of old objects.
std::atomic< bool >	m_dirty
	True if there are any objects pending deletion.

Detailed Description

Base object class for RCU-style synchronization for Athena.

Definition at line 146 of file RCUObject.h.

Member Typedef Documentation

◆ lock_t

typedef std::unique_lock<mutex_t> Athena::IRCUObject::lock_t

protected

Definition at line 214 of file RCUObject.h.

◆ mutex_t

typedef std::mutex Athena::IRCUObject::mutex_t

protected

Definition at line 213 of file RCUObject.h.

Member Enumeration Documentation

◆ NoObjectEnum

enum Athena::IRCUObject::NoObjectEnum

Value to pass to a constructor to mark that we shouldn't allocate an object.

Enumerator
NoObject

Definition at line 151 of file RCUObject.h.

151{ NoObject };

Athena::IRCUObject::NoObject

@ NoObject

Definition RCUObject.h:151

Constructor & Destructor Documentation

◆ IRCUObject() [1/4]

Athena::IRCUObject::IRCUObject ( IRCUSvc & svc )

Constructor, with RCUSvc.

Parameters

svc	Service with which to register.

The service will call quiescent at the end of each event.

Definition at line 72 of file RCUObject.cxx.

  : m_svc (&svc),
    m_graceSets (std::make_unique<RCUObjectGraceSets> (svc.getNumSlots())),
    m_nold(0),
    m_dirty(false)
{
  m_svc->add (this);
}

◆ IRCUObject() [2/4]

Athena::IRCUObject::IRCUObject ( size_t nslots )

Constructor, with event slot count.

Parameters

nslots Number of active event slots.

This version does not register with a service.

Definition at line 88 of file RCUObject.cxx.

  : m_svc (nullptr),
    m_graceSets (std::make_unique<RCUObjectGraceSets> (nslots)),
    m_nold(0),
    m_dirty(false)
{
}

◆ IRCUObject() [3/4]

Athena::IRCUObject::IRCUObject ( IRCUObject && other )

Move constructor.

Allow passing these objects via move.

Definition at line 114 of file RCUObject.cxx.

  : m_svc (other.m_svc),
    m_graceSets (std::move (other.m_graceSets)),
    m_nold (other.m_nold),
    m_dirty (false)
{
  other.m_nold = 0;
  if (other.m_dirty) {
    m_dirty = true;
  }
  other.m_dirty = false;
  if (m_svc) {
    if (m_svc->remove (&other).isFailure()) {
      std::abort();
    }
    other.m_svc = nullptr;
    m_svc->add (this);
  }
}

◆ IRCUObject() [4/4]

Athena::IRCUObject::IRCUObject ( const IRCUObject & )

delete

◆ ~IRCUObject()

Athena::IRCUObject::~IRCUObject ( )

virtual

Destructor.

Remove this object from the service if it has been registered.

Definition at line 102 of file RCUObject.cxx.

{
  if (m_svc && m_svc->remove (this).isFailure())
    std::abort();
}

Member Function Documentation

◆ clearAll()

virtual void Athena::IRCUObject::clearAll ( lock_t & )

protectedpure virtual

Delete all objects.

Parameters

Lock	object (external locking).

The caller must be holding the mutex for this object.

Implemented in Athena::RCUObject< T >, and Athena::RCUObject< InputRenameMap_t >.

◆ clearOld()

virtual bool Athena::IRCUObject::clearOld	(	lock_t &	,
		size_t	nold )

protectedpure virtual

Delete old objects.

Parameters

Lock	object (external locking).
nold	Number of old objects to delete.

The caller must be holding the mutex for this object. Returns true if there are no more objects pending deletion.

Implemented in Athena::RCUObject< T >, and Athena::RCUObject< InputRenameMap_t >.

◆ endGrace()

bool Athena::IRCUObject::endGrace	(	lock_t &	lock,
		const EventContext &	ctx )

protected

Declare that the grace period for a slot is ending.

Parameters

Lock	object (external locking).
ctx	Event context for the slot.

Returns: true if any slot is still in a grace period. false if no slots are in a grace period.

The caller must be holding the mutex for this object.

Parameters

lock	Lock object (external locking).
ctx	Event context for the slot.

Returns: true if any slot is still in a grace period. false if no slots are in a grace period.

The caller must be holding the mutex for this object.

Definition at line 165 of file RCUObject.cxx.

{
  return ::endGrace (ctx, m_graceSets->m_grace);
}

◆ makeOld()

void Athena::IRCUObject::makeOld	(	lock_t &	lock,
		size_t	garbageSize )

protected

Make existing pending objects old, if possible.

Parameters

lock	Lock object (external locking).
garbageSize	Present number of objects pending deletion.

A new object is about to be added to the list of objects pending deletion. If there are any existing pending objects and there are no existing old objects, make the current pending objects old.

Definition at line 193 of file RCUObject.cxx.

{
  if (garbageSize && m_nold == 0) {
    m_graceSets->m_oldGrace = m_graceSets->m_grace;
    m_nold = garbageSize;
  }
}

◆ mutex()

mutex_t & Athena::IRCUObject::mutex ( )

protected

Return the mutex for this object.

◆ operator=() [1/2]

IRCUObject & Athena::IRCUObject::operator= ( const IRCUObject & )

delete

◆ operator=() [2/2]

IRCUObject & Athena::IRCUObject::operator= ( IRCUObject && )

delete

◆ quiescent() [1/2]

void Athena::IRCUObject::quiescent ( )

Declare the current event slot of this object to be quiescent.

This will take out a lock and possibly trigger object cleanup.

◆ quiescent() [2/2]

void Athena::IRCUObject::quiescent ( const EventContext & ctx )

Declare the event slot ctx of this object to be quiescent.

Parameters

ctx	The event context.

This will take out a lock and possibly trigger object cleanup.

◆ quiescentOol()

void Athena::IRCUObject::quiescentOol ( const EventContext & ctx )

private

Out-of-line part of quiescent().

Definition at line 138 of file RCUObject.cxx.

{
  // We get here after the dirty flag has already been checked.
  lock_t g (m_mutex);
  if (!::endGrace(ctx, m_graceSets->m_grace)) {
    clearAll(g);
    m_nold = 0;
    m_dirty = false;
  }
  else if (m_nold > 0 && !::endGrace(ctx, m_graceSets->m_oldGrace)) {
    if (clearOld(g, m_nold)) {
      m_dirty = false;
    }
    m_nold = 0;
  }
}

◆ setGrace()

void Athena::IRCUObject::setGrace ( lock_t & )

protected

Declare that all slots are in a grace period.

Parameters

Lock	object (external locking).

The caller must be holding the mutex for this object.

Definition at line 177 of file RCUObject.cxx.

{
  m_graceSets->m_grace.set();
  if (!m_dirty) m_dirty = true;
}

Member Data Documentation

◆ m_dirty

std::atomic<bool> Athena::IRCUObject::m_dirty

private

True if there are any objects pending deletion.

Used to avoid taking the lock in quiescent() if there's nothing to do.

Definition at line 300 of file RCUObject.h.

◆ m_graceSets

std::unique_ptr<RCUObjectGraceSets> Athena::IRCUObject::m_graceSets

private

Holds the current and old grace period bitmasks.

Split off into a separate object to reduce header dependencies.

Definition at line 292 of file RCUObject.h.

◆ m_mutex

std::mutex Athena::IRCUObject::m_mutex

private

The mutex for this object.

Definition at line 285 of file RCUObject.h.

◆ m_nold

size_t Athena::IRCUObject::m_nold

private

Number of old objects.

The objects at the end of the garbage list are old.

Definition at line 296 of file RCUObject.h.

◆ m_svc

IRCUSvc* Athena::IRCUObject::m_svc

private

The service with which we're registered, or null.

Definition at line 288 of file RCUObject.h.

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

Public Types

Public Member Functions

Protected Types

Protected Member Functions

Private Member Functions

Private Attributes

Detailed Description

Member Typedef Documentation

◆ lock_t

◆ mutex_t

Member Enumeration Documentation

◆ NoObjectEnum

Constructor & Destructor Documentation

◆ IRCUObject() [1/4]

◆ IRCUObject() [2/4]

◆ IRCUObject() [3/4]

◆ IRCUObject() [4/4]

◆ ~IRCUObject()

Member Function Documentation

◆ clearAll()

◆ clearOld()

◆ endGrace()

◆ makeOld()

◆ mutex()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ quiescent() [1/2]

◆ quiescent() [2/2]

◆ quiescentOol()

◆ setGrace()

Member Data Documentation

◆ m_dirty

◆ m_graceSets

◆ m_mutex

◆ m_nold

◆ m_svc