mongo::LockHead Struct Reference

There is one of these objects for each resource that has a lock request. More...

Detailed Description

There is one of these objects for each resource that has a lock request.

Empty objects (i.e. LockHead with no requests) are allowed to exist on the lock manager's hash table.

The memory and lifetime is controlled entirely by the LockManager class.

Not thread-safe and should only be accessed under the LockManager's bucket lock. Must be locked before locking a partition, not after.

Public Member Functions
void	initNew (ResourceId resId)
	Used for initialization of a LockHead, which might have been retrieved from cache and also in order to keep the LockHead structure a POD. More...
bool	partitioned () const
	True iff there may be partitions with granted requests for this resource. More...
LockRequest *	findRequest (LockerId lockerId) const
	Locates the request corresponding to the particular locker or returns nullptr. More...
LockResult	newRequest (LockRequest *request)
	Finish creation of request and put it on the LockHead's conflict or granted queues. More...
void	migratePartitionedLockHeads ()
	Lock each partitioned LockHead in turn, and move any (granted) intent mode requests for lock->resourceId to lock, which must itself already be locked. More...
void	incGrantedModeCount (LockMode mode)
void	decGrantedModeCount (LockMode mode)
void	incConflictModeCount (LockMode mode)
void	decConflictModeCount (LockMode mode)

Public Attributes
ResourceId	resourceId
LockRequestList	grantedList
uint32_t	grantedCounts [LockModesCount]
uint32_t	grantedModes
LockRequestList	conflictList
uint32_t	conflictCounts [LockModesCount]
uint32_t	conflictModes
std::vector< LockManager::Partition * >	partitions
uint32_t	conversionsCount
uint32_t	compatibleFirstCount

Member Function Documentation

decConflictModeCount()

void mongo::LockHead::decConflictModeCount ( LockMode  mode )

inline

decGrantedModeCount()

void mongo::LockHead::decGrantedModeCount ( LockMode  mode )

inline

findRequest()

LockRequest* mongo::LockHead::findRequest ( LockerId  lockerId ) const

inline

Locates the request corresponding to the particular locker or returns nullptr.

Must be called with the bucket holding this lock head locked.

incConflictModeCount()

void mongo::LockHead::incConflictModeCount ( LockMode  mode )

inline

incGrantedModeCount()

void mongo::LockHead::incGrantedModeCount ( LockMode  mode )

inline

initNew()

void mongo::LockHead::initNew ( ResourceId  resId )

inline

Used for initialization of a LockHead, which might have been retrieved from cache and also in order to keep the LockHead structure a POD.

migratePartitionedLockHeads()

void mongo::LockHead::migratePartitionedLockHeads

(

)

Lock each partitioned LockHead in turn, and move any (granted) intent mode requests for lock->resourceId to lock, which must itself already be locked.

newRequest()

LockResult mongo::LockHead::newRequest ( LockRequest *  request )

inline

Finish creation of request and put it on the LockHead's conflict or granted queues.

Returns LOCK_WAITING for conflict case and LOCK_OK otherwise.

partitioned()

bool mongo::LockHead::partitioned ( ) const

inline

True iff there may be partitions with granted requests for this resource.

Member Data Documentation

compatibleFirstCount

uint32_t mongo::LockHead::compatibleFirstCount

conflictCounts

uint32_t mongo::LockHead::conflictCounts[LockModesCount]

conflictList

LockRequestList mongo::LockHead::conflictList

conflictModes

uint32_t mongo::LockHead::conflictModes

conversionsCount

uint32_t mongo::LockHead::conversionsCount

grantedCounts

uint32_t mongo::LockHead::grantedCounts[LockModesCount]

grantedList

LockRequestList mongo::LockHead::grantedList

grantedModes

uint32_t mongo::LockHead::grantedModes

partitions

std::vector<LockManager::Partition*> mongo::LockHead::partitions

resourceId

ResourceId mongo::LockHead::resourceId

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

• /home/louis/git/mongodbsource.github.io/src/src/mongo/db/concurrency/lock_manager.cpp