rocksdb/db/trim_history_scheduler.cc

60 lines
1.4 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. 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 "db/trim_history_scheduler.h"
#include <cassert>
#include "db/column_family.h"
namespace rocksdb {
void TrimHistoryScheduler::ScheduleWork(ColumnFamilyData* cfd) {
std::lock_guard<std::mutex> lock(checking_mutex_);
cfd->Ref();
cfds_.push_back(cfd);
is_empty_.store(false, std::memory_order_relaxed);
}
ColumnFamilyData* TrimHistoryScheduler::TakeNextColumnFamily() {
std::lock_guard<std::mutex> lock(checking_mutex_);
while (true) {
if (cfds_.empty()) {
return nullptr;
}
ColumnFamilyData* cfd = cfds_.back();
cfds_.pop_back();
if (cfds_.empty()) {
is_empty_.store(true, std::memory_order_relaxed);
}
if (!cfd->IsDropped()) {
// success
return cfd;
}
if (cfd->Unref()) {
// no longer relevant, retry
delete cfd;
}
}
}
bool TrimHistoryScheduler::Empty() {
bool is_empty = is_empty_.load(std::memory_order_relaxed);
return is_empty;
}
void TrimHistoryScheduler::Clear() {
ColumnFamilyData* cfd;
while ((cfd = TakeNextColumnFamily()) != nullptr) {
if (cfd->Unref()) {
delete cfd;
}
}
assert(Empty());
}
} // namespace rocksdb