rocksdb/utilities/object_registry.cc
mrambacher 0fb938c448 Add support to the ObjectRegistry for ManagedObjects (#8658)
Summary:
ManagedObjects are  shared pointer objects where RocksDB wants to share a single object between multiple configurations.  For example, the Cache may be shared between multiple column families/tables or the Statistics may be shared between multiple databases.

ManagedObjects are stored in the ObjectRegistry by Type (e.g. Cache) and ID.  For a given type/ID name, a single object is stored.

APIs were added to get/set/create these objects.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8658

Reviewed By: pdillinger

Differential Revision: D30806273

Pulled By: mrambacher

fbshipit-source-id: 832ac4423b210c4c4b4a456b35897334775d3160
2021-09-10 05:21:04 -07:00

190 lines
5.9 KiB
C++

// Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#include "rocksdb/utilities/object_registry.h"
#include "logging/logging.h"
#include "rocksdb/customizable.h"
#include "rocksdb/env.h"
#include "util/string_util.h"
namespace ROCKSDB_NAMESPACE {
#ifndef ROCKSDB_LITE
// Looks through the "type" factories for one that matches "name".
// If found, returns the pointer to the Entry matching this name.
// Otherwise, nullptr is returned
const ObjectLibrary::Entry *ObjectLibrary::FindEntry(
const std::string &type, const std::string &name) const {
std::unique_lock<std::mutex> lock(mu_);
auto entries = entries_.find(type);
if (entries != entries_.end()) {
for (const auto &entry : entries->second) {
if (entry->matches(name)) {
return entry.get();
}
}
}
return nullptr;
}
void ObjectLibrary::AddEntry(const std::string &type,
std::unique_ptr<Entry> &entry) {
std::unique_lock<std::mutex> lock(mu_);
auto &entries = entries_[type];
entries.emplace_back(std::move(entry));
}
size_t ObjectLibrary::GetFactoryCount(size_t *types) const {
std::unique_lock<std::mutex> lock(mu_);
*types = entries_.size();
size_t factories = 0;
for (const auto &e : entries_) {
factories += e.second.size();
}
return factories;
}
void ObjectLibrary::Dump(Logger *logger) const {
std::unique_lock<std::mutex> lock(mu_);
for (const auto &iter : entries_) {
ROCKS_LOG_HEADER(logger, " Registered factories for type[%s] ",
iter.first.c_str());
bool printed_one = false;
for (const auto &e : iter.second) {
ROCKS_LOG_HEADER(logger, "%c %s", (printed_one) ? ',' : ':',
e->Name().c_str());
printed_one = true;
}
}
ROCKS_LOG_HEADER(logger, "\n");
}
// Returns the Default singleton instance of the ObjectLibrary
// This instance will contain most of the "standard" registered objects
std::shared_ptr<ObjectLibrary> &ObjectLibrary::Default() {
static std::shared_ptr<ObjectLibrary> instance =
std::make_shared<ObjectLibrary>("default");
return instance;
}
std::shared_ptr<ObjectRegistry> ObjectRegistry::Default() {
static std::shared_ptr<ObjectRegistry> instance(
new ObjectRegistry(ObjectLibrary::Default()));
return instance;
}
std::shared_ptr<ObjectRegistry> ObjectRegistry::NewInstance() {
return std::make_shared<ObjectRegistry>(Default());
}
std::shared_ptr<ObjectRegistry> ObjectRegistry::NewInstance(
const std::shared_ptr<ObjectRegistry> &parent) {
return std::make_shared<ObjectRegistry>(parent);
}
// Searches (from back to front) the libraries looking for the
// an entry that matches this pattern.
// Returns the entry if it is found, and nullptr otherwise
const ObjectLibrary::Entry *ObjectRegistry::FindEntry(
const std::string &type, const std::string &name) const {
{
std::unique_lock<std::mutex> lock(library_mutex_);
for (auto iter = libraries_.crbegin(); iter != libraries_.crend(); ++iter) {
const auto *entry = iter->get()->FindEntry(type, name);
if (entry != nullptr) {
return entry;
}
}
}
if (parent_ != nullptr) {
return parent_->FindEntry(type, name);
} else {
return nullptr;
}
}
Status ObjectRegistry::SetManagedObject(
const std::string &type, const std::string &id,
const std::shared_ptr<Customizable> &object) {
std::string object_key = ToManagedObjectKey(type, id);
std::shared_ptr<Customizable> curr;
if (parent_ != nullptr) {
curr = parent_->GetManagedObject(type, id);
}
if (curr == nullptr) {
// We did not find the object in any parent. Update in the current
std::unique_lock<std::mutex> lock(objects_mutex_);
auto iter = managed_objects_.find(object_key);
if (iter != managed_objects_.end()) { // The object exists
curr = iter->second.lock();
if (curr != nullptr && curr != object) {
return Status::InvalidArgument("Object already exists: ", object_key);
} else {
iter->second = object;
}
} else {
// The object does not exist. Add it
managed_objects_[object_key] = object;
}
} else if (curr != object) {
return Status::InvalidArgument("Object already exists: ", object_key);
}
return Status::OK();
}
std::shared_ptr<Customizable> ObjectRegistry::GetManagedObject(
const std::string &type, const std::string &id) const {
{
std::unique_lock<std::mutex> lock(objects_mutex_);
auto iter = managed_objects_.find(ToManagedObjectKey(type, id));
if (iter != managed_objects_.end()) {
return iter->second.lock();
}
}
if (parent_ != nullptr) {
return parent_->GetManagedObject(type, id);
} else {
return nullptr;
}
}
Status ObjectRegistry::ListManagedObjects(
const std::string &type, const std::string &name,
std::vector<std::shared_ptr<Customizable>> *results) const {
{
std::string key = ToManagedObjectKey(type, name);
std::unique_lock<std::mutex> lock(objects_mutex_);
for (auto iter = managed_objects_.lower_bound(key);
iter != managed_objects_.end() && StartsWith(iter->first, key);
++iter) {
auto shared = iter->second.lock();
if (shared != nullptr) {
if (name.empty() || shared->IsInstanceOf(name)) {
results->emplace_back(shared);
}
}
}
}
if (parent_ != nullptr) {
return parent_->ListManagedObjects(type, name, results);
} else {
return Status::OK();
}
}
void ObjectRegistry::Dump(Logger *logger) const {
{
std::unique_lock<std::mutex> lock(library_mutex_);
for (auto iter = libraries_.crbegin(); iter != libraries_.crend(); ++iter) {
iter->get()->Dump(logger);
}
}
if (parent_ != nullptr) {
parent_->Dump(logger);
}
}
#endif // ROCKSDB_LITE
} // namespace ROCKSDB_NAMESPACE