diff options
Diffstat (limited to 'src/mongo/db/service_context.h')
| -rw-r--r-- | src/mongo/db/service_context.h | 568 |
1 files changed, 286 insertions, 282 deletions
diff --git a/src/mongo/db/service_context.h b/src/mongo/db/service_context.h index 066f6c6bc70..8f07c34d5a1 100644 --- a/src/mongo/db/service_context.h +++ b/src/mongo/db/service_context.h @@ -40,362 +40,366 @@ namespace mongo { - class AbstractMessagingPort; - class Client; - class OperationContext; - class OpObserver; +class AbstractMessagingPort; +class Client; +class OperationContext; +class OpObserver; +/** + * Classes that implement this interface can receive notification on killOp. + * + * See GlobalEnvironmentExperiment::registerKillOpListener() for more information, including + * limitations on the lifetime of registered listeners. + */ +class KillOpListenerInterface { +public: /** - * Classes that implement this interface can receive notification on killOp. - * - * See GlobalEnvironmentExperiment::registerKillOpListener() for more information, including - * limitations on the lifetime of registered listeners. + * Will be called *after* ops have been told they should die. + * Callback must not fail. */ - class KillOpListenerInterface { - public: - /** - * Will be called *after* ops have been told they should die. - * Callback must not fail. - */ - virtual void interrupt(unsigned opId) = 0; - virtual void interruptAll() = 0; + virtual void interrupt(unsigned opId) = 0; + virtual void interruptAll() = 0; - protected: - // Should not delete through a pointer of this type - virtual ~KillOpListenerInterface() {} - }; +protected: + // Should not delete through a pointer of this type + virtual ~KillOpListenerInterface() {} +}; + +class StorageFactoriesIterator { + MONGO_DISALLOW_COPYING(StorageFactoriesIterator); + +public: + virtual ~StorageFactoriesIterator() {} + virtual bool more() const = 0; + virtual const StorageEngine::Factory* next() = 0; - class StorageFactoriesIterator { - MONGO_DISALLOW_COPYING(StorageFactoriesIterator); +protected: + StorageFactoriesIterator() {} +}; + +/** + * Class representing the context of a service, such as a MongoD database service or + * a MongoS routing service. + * + * A ServiceContext is the root of a hierarchy of contexts. A ServiceContext owns + * zero or more Clients, which in turn each own OperationContexts. + */ +class ServiceContext : public Decorable<ServiceContext> { + MONGO_DISALLOW_COPYING(ServiceContext); + +public: + /** + * Special deleter used for cleaning up Client objects owned by a ServiceContext. + * See UniqueClient, below. + */ + class ClientDeleter { public: - virtual ~StorageFactoriesIterator() { } - virtual bool more() const = 0; - virtual const StorageEngine::Factory* next() = 0; - protected: - StorageFactoriesIterator() { } + void operator()(Client* client) const; }; /** - * Class representing the context of a service, such as a MongoD database service or - * a MongoS routing service. - * - * A ServiceContext is the root of a hierarchy of contexts. A ServiceContext owns - * zero or more Clients, which in turn each own OperationContexts. + * Observer interface implemented to hook client and operation context creation and + * destruction. */ - class ServiceContext : public Decorable<ServiceContext> { - MONGO_DISALLOW_COPYING(ServiceContext); + class ClientObserver { public: - /** - * Special deleter used for cleaning up Client objects owned by a ServiceContext. - * See UniqueClient, below. - */ - class ClientDeleter { - public: - void operator()(Client* client) const; - }; + virtual ~ClientObserver() = default; /** - * Observer interface implemented to hook client and operation context creation and - * destruction. - */ - class ClientObserver { - public: - virtual ~ClientObserver() = default; - - /** - * Hook called after a new client "client" is created on a service by - * service->makeClient(). - * - * For a given client and registered instance of ClientObserver, if onCreateClient - * returns without throwing an exception, onDestroyClient will be called when "client" - * is deleted. - */ - virtual void onCreateClient(Client* client) = 0; - - /** - * Hook called on a "client" created by a service before deleting "client". - * - * Like a destructor, must not throw exceptions. - */ - virtual void onDestroyClient(Client* client) = 0; - - /** - * Hook called after a new operation context is created on a client by - * service->makeOperationContext(client) or client->makeOperationContext(). - * - * For a given operation context and registered instance of ClientObserver, if - * onCreateOperationContext returns without throwing an exception, - * onDestroyOperationContext will be called when "opCtx" is deleted. - */ - virtual void onCreateOperationContext(OperationContext* opCtx) = 0; - - /** - * Hook called on a "opCtx" created by a service before deleting "opCtx". - * - * Like a destructor, must not throw exceptions. - */ - virtual void onDestroyOperationContext(OperationContext* opCtx) = 0; - }; - - using ClientSet = unordered_set<Client*>; - - /** - * Cursor for enumerating the live Client objects belonging to a ServiceContext. + * Hook called after a new client "client" is created on a service by + * service->makeClient(). * - * Lifetimes of this type are synchronized with client creation and destruction. - */ - class LockedClientsCursor { - public: - /** - * Constructs a cursor for enumerating the clients of "service", blocking "service" from - * creating or destroying Client objects until this instance is destroyed. - */ - explicit LockedClientsCursor(ServiceContext* service); - - /** - * Returns the next client in the enumeration, or nullptr if there are no more clients. - */ - Client* next(); - - private: - stdx::unique_lock<stdx::mutex> _lock; - ClientSet::const_iterator _curr; - ClientSet::const_iterator _end; - }; - - /** - * Special deleter used for cleaning up OperationContext objects owned by a ServiceContext. - * See UniqueOperationContext, below. - */ - class OperationContextDeleter { - public: - void operator()(OperationContext* opCtx) const; - }; - - /** - * This is the unique handle type for Clients created by a ServiceContext. + * For a given client and registered instance of ClientObserver, if onCreateClient + * returns without throwing an exception, onDestroyClient will be called when "client" + * is deleted. */ - using UniqueClient = std::unique_ptr<Client, ClientDeleter>; + virtual void onCreateClient(Client* client) = 0; /** - * This is the unique handle type for OperationContexts created by a ServiceContext. - */ - using UniqueOperationContext = std::unique_ptr<OperationContext, OperationContextDeleter>; - - virtual ~ServiceContext(); - - /** - * Registers an observer of lifecycle events on Clients created by this ServiceContext. - * - * See the ClientObserver type, above, for details. + * Hook called on a "client" created by a service before deleting "client". * - * All calls to registerClientObserver must complete before ServiceContext - * is used in multi-threaded operation, or is used to create clients via calls - * to makeClient. + * Like a destructor, must not throw exceptions. */ - void registerClientObserver(std::unique_ptr<ClientObserver> observer); + virtual void onDestroyClient(Client* client) = 0; /** - * Creates a new Client object representing a client session associated with this - * ServiceContext. + * Hook called after a new operation context is created on a client by + * service->makeOperationContext(client) or client->makeOperationContext(). * - * The "desc" string is used to set a descriptive name for the client, used in logging. - * - * If supplied, "p" is the communication channel used for communicating with the client. + * For a given operation context and registered instance of ClientObserver, if + * onCreateOperationContext returns without throwing an exception, + * onDestroyOperationContext will be called when "opCtx" is deleted. */ - UniqueClient makeClient(std::string desc, AbstractMessagingPort* p = nullptr); + virtual void onCreateOperationContext(OperationContext* opCtx) = 0; /** - * Creates a new OperationContext on "client". + * Hook called on a "opCtx" created by a service before deleting "opCtx". * - * "client" must not have an active operation context. + * Like a destructor, must not throw exceptions. */ - UniqueOperationContext makeOperationContext(Client* client); + virtual void onDestroyOperationContext(OperationContext* opCtx) = 0; + }; - // - // Storage - // - - /** - * Register a storage engine. Called from a MONGO_INIT that depends on initializiation of - * the global environment. - * Ownership of 'factory' is transferred to global environment upon registration. - */ - virtual void registerStorageEngine(const std::string& name, - const StorageEngine::Factory* factory) = 0; + using ClientSet = unordered_set<Client*>; + /** + * Cursor for enumerating the live Client objects belonging to a ServiceContext. + * + * Lifetimes of this type are synchronized with client creation and destruction. + */ + class LockedClientsCursor { + public: /** - * Returns true if "name" refers to a registered storage engine. + * Constructs a cursor for enumerating the clients of "service", blocking "service" from + * creating or destroying Client objects until this instance is destroyed. */ - virtual bool isRegisteredStorageEngine(const std::string& name) = 0; + explicit LockedClientsCursor(ServiceContext* service); /** - * Produce an iterator over all registered storage engine factories. - * Caller owns the returned object and is responsible for deleting when finished. - * - * Never returns nullptr. + * Returns the next client in the enumeration, or nullptr if there are no more clients. */ - virtual StorageFactoriesIterator* makeStorageFactoriesIterator() = 0; + Client* next(); - virtual void initializeGlobalStorageEngine() = 0; + private: + stdx::unique_lock<stdx::mutex> _lock; + ClientSet::const_iterator _curr; + ClientSet::const_iterator _end; + }; - /** - * Shuts down storage engine cleanly and releases any locks on mongod.lock. - */ - virtual void shutdownGlobalStorageEngineCleanly() = 0; + /** + * Special deleter used for cleaning up OperationContext objects owned by a ServiceContext. + * See UniqueOperationContext, below. + */ + class OperationContextDeleter { + public: + void operator()(OperationContext* opCtx) const; + }; - /** - * Return the storage engine instance we're using. - */ - virtual StorageEngine* getGlobalStorageEngine() = 0; + /** + * This is the unique handle type for Clients created by a ServiceContext. + */ + using UniqueClient = std::unique_ptr<Client, ClientDeleter>; - // - // Global operation management. This may not belong here and there may be too many methods - // here. - // + /** + * This is the unique handle type for OperationContexts created by a ServiceContext. + */ + using UniqueOperationContext = std::unique_ptr<OperationContext, OperationContextDeleter>; - /** - * Signal all OperationContext(s) that they have been killed. - */ - virtual void setKillAllOperations() = 0; + virtual ~ServiceContext(); - /** - * Reset the operation kill state after a killAllOperations. - * Used for testing. - */ - virtual void unsetKillAllOperations() = 0; + /** + * Registers an observer of lifecycle events on Clients created by this ServiceContext. + * + * See the ClientObserver type, above, for details. + * + * All calls to registerClientObserver must complete before ServiceContext + * is used in multi-threaded operation, or is used to create clients via calls + * to makeClient. + */ + void registerClientObserver(std::unique_ptr<ClientObserver> observer); - /** - * Get the state for killing all operations. - */ - virtual bool getKillAllOperations() = 0; + /** + * Creates a new Client object representing a client session associated with this + * ServiceContext. + * + * The "desc" string is used to set a descriptive name for the client, used in logging. + * + * If supplied, "p" is the communication channel used for communicating with the client. + */ + UniqueClient makeClient(std::string desc, AbstractMessagingPort* p = nullptr); - /** - * @param i opid of operation to kill - * @return if operation was found - **/ - virtual bool killOperation(unsigned int opId) = 0; + /** + * Creates a new OperationContext on "client". + * + * "client" must not have an active operation context. + */ + UniqueOperationContext makeOperationContext(Client* client); - /** - * Kills all operations that have a Client that is associated with an incoming user - * connection, except for the one associated with txn. - */ - virtual void killAllUserOperations(const OperationContext* txn) = 0; + // + // Storage + // - /** - * Registers a listener to be notified each time an op is killed. - * - * listener does not become owned by the environment. As there is currently no way to - * unregister, the listener object must outlive this ServiceContext object. - */ - virtual void registerKillOpListener(KillOpListenerInterface* listener) = 0; + /** + * Register a storage engine. Called from a MONGO_INIT that depends on initializiation of + * the global environment. + * Ownership of 'factory' is transferred to global environment upon registration. + */ + virtual void registerStorageEngine(const std::string& name, + const StorageEngine::Factory* factory) = 0; - // - // Global OpObserver. - // + /** + * Returns true if "name" refers to a registered storage engine. + */ + virtual bool isRegisteredStorageEngine(const std::string& name) = 0; - /** - * Set the OpObserver. - */ - virtual void setOpObserver(std::unique_ptr<OpObserver> opObserver) = 0; + /** + * Produce an iterator over all registered storage engine factories. + * Caller owns the returned object and is responsible for deleting when finished. + * + * Never returns nullptr. + */ + virtual StorageFactoriesIterator* makeStorageFactoriesIterator() = 0; - /** - * Return the OpObserver instance we're using. - */ - virtual OpObserver* getOpObserver() = 0; + virtual void initializeGlobalStorageEngine() = 0; - /** - * Returns the tick source set in this context. - */ - TickSource* getTickSource() const; + /** + * Shuts down storage engine cleanly and releases any locks on mongod.lock. + */ + virtual void shutdownGlobalStorageEngineCleanly() = 0; - /** - * Replaces the current tick source with a new one. In other words, the old tick source - * will be destroyed. So make sure that no one is using the old tick source when - * calling this. - */ - void setTickSource(std::unique_ptr<TickSource> newSource); + /** + * Return the storage engine instance we're using. + */ + virtual StorageEngine* getGlobalStorageEngine() = 0; - protected: - ServiceContext() = default; + // + // Global operation management. This may not belong here and there may be too many methods + // here. + // - /** - * Mutex used to synchronize access to mutable state of this ServiceContext instance, - * including possibly by its subclasses. - */ - stdx::mutex _mutex; + /** + * Signal all OperationContext(s) that they have been killed. + */ + virtual void setKillAllOperations() = 0; - private: - /** - * Returns a new OperationContext. Private, for use by makeOperationContext. - */ - virtual std::unique_ptr<OperationContext> _newOpCtx(Client* client) = 0; + /** + * Reset the operation kill state after a killAllOperations. + * Used for testing. + */ + virtual void unsetKillAllOperations() = 0; - /** - * Vector of registered observers. - */ - std::vector<std::unique_ptr<ClientObserver>> _clientObservers; - ClientSet _clients; + /** + * Get the state for killing all operations. + */ + virtual bool getKillAllOperations() = 0; - std::unique_ptr<TickSource> _tickSource; - }; + /** + * @param i opid of operation to kill + * @return if operation was found + **/ + virtual bool killOperation(unsigned int opId) = 0; /** - * Returns true if there is a global ServiceContext. + * Kills all operations that have a Client that is associated with an incoming user + * connection, except for the one associated with txn. */ - bool hasGlobalServiceContext(); + virtual void killAllUserOperations(const OperationContext* txn) = 0; /** - * Returns the singleton ServiceContext for this server process. - * - * Fatal if there is currently no global ServiceContext. + * Registers a listener to be notified each time an op is killed. * - * Caller does not own pointer. + * listener does not become owned by the environment. As there is currently no way to + * unregister, the listener object must outlive this ServiceContext object. */ - ServiceContext* getGlobalServiceContext(); + virtual void registerKillOpListener(KillOpListenerInterface* listener) = 0; + + // + // Global OpObserver. + // /** - * Sets the global ServiceContext. If 'serviceContext' is NULL, un-sets and deletes - * the current global ServiceContext. - * - * Takes ownership of 'serviceContext'. + * Set the OpObserver. */ - void setGlobalServiceContext(std::unique_ptr<ServiceContext>&& serviceContext); + virtual void setOpObserver(std::unique_ptr<OpObserver> opObserver) = 0; /** - * Shortcut for querying the storage engine about whether it supports document-level locking. - * If this call becomes too expensive, we could cache the value somewhere so we don't have to - * fetch the storage engine every time. + * Return the OpObserver instance we're using. */ - bool supportsDocLocking(); + virtual OpObserver* getOpObserver() = 0; /** - * Returns true if the storage engine in use is MMAPV1. + * Returns the tick source set in this context. */ - bool isMMAPV1(); - - /* - * Extracts the storageEngine bson from the CollectionOptions provided. Loops through each - * provided storageEngine and asks the matching registered storage engine if the - * collection/index options are valid. Returns an error if the collection/index options are - * invalid. - * If no matching registered storage engine is found, return an error. - * Validation function 'func' must be either: - * - &StorageEngine::Factory::validateCollectionStorageOptions; or - * - &StorageEngine::Factory::validateIndexStorageOptions + TickSource* getTickSource() const; + + /** + * Replaces the current tick source with a new one. In other words, the old tick source + * will be destroyed. So make sure that no one is using the old tick source when + * calling this. */ - Status validateStorageOptions(const BSONObj& storageEngineOptions, - stdx::function<Status (const StorageEngine::Factory* const, const BSONObj&)> validateFunc); + void setTickSource(std::unique_ptr<TickSource> newSource); + +protected: + ServiceContext() = default; - /* - * Returns a BSONArray containing the names of available storage engines, or an empty - * array if there is no global ServiceContext + /** + * Mutex used to synchronize access to mutable state of this ServiceContext instance, + * including possibly by its subclasses. */ - BSONArray storageEngineList(); + stdx::mutex _mutex; - /* - * Appends a the list of available storage engines to a BSONObjBuilder for reporting purposes. +private: + /** + * Returns a new OperationContext. Private, for use by makeOperationContext. */ - void appendStorageEngineList(BSONObjBuilder* result); + virtual std::unique_ptr<OperationContext> _newOpCtx(Client* client) = 0; + + /** + * Vector of registered observers. + */ + std::vector<std::unique_ptr<ClientObserver>> _clientObservers; + ClientSet _clients; + + std::unique_ptr<TickSource> _tickSource; +}; + +/** + * Returns true if there is a global ServiceContext. + */ +bool hasGlobalServiceContext(); + +/** + * Returns the singleton ServiceContext for this server process. + * + * Fatal if there is currently no global ServiceContext. + * + * Caller does not own pointer. + */ +ServiceContext* getGlobalServiceContext(); + +/** + * Sets the global ServiceContext. If 'serviceContext' is NULL, un-sets and deletes + * the current global ServiceContext. + * + * Takes ownership of 'serviceContext'. + */ +void setGlobalServiceContext(std::unique_ptr<ServiceContext>&& serviceContext); + +/** + * Shortcut for querying the storage engine about whether it supports document-level locking. + * If this call becomes too expensive, we could cache the value somewhere so we don't have to + * fetch the storage engine every time. + */ +bool supportsDocLocking(); + +/** + * Returns true if the storage engine in use is MMAPV1. + */ +bool isMMAPV1(); + +/* + * Extracts the storageEngine bson from the CollectionOptions provided. Loops through each + * provided storageEngine and asks the matching registered storage engine if the + * collection/index options are valid. Returns an error if the collection/index options are + * invalid. + * If no matching registered storage engine is found, return an error. + * Validation function 'func' must be either: + * - &StorageEngine::Factory::validateCollectionStorageOptions; or + * - &StorageEngine::Factory::validateIndexStorageOptions + */ +Status validateStorageOptions( + const BSONObj& storageEngineOptions, + stdx::function<Status(const StorageEngine::Factory* const, const BSONObj&)> validateFunc); + +/* + * Returns a BSONArray containing the names of available storage engines, or an empty + * array if there is no global ServiceContext + */ +BSONArray storageEngineList(); + +/* + * Appends a the list of available storage engines to a BSONObjBuilder for reporting purposes. + */ +void appendStorageEngineList(BSONObjBuilder* result); } // namespace mongo |