github.com/zuoyebang/bitalosdb@v1.1.1-0.20240516111551-79a8c4d8ce20/flushable.go (about) 1 // Copyright 2021 The Bitalosdb author(hustxrb@163.com) and other contributors. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 package bitalosdb 16 17 import ( 18 "fmt" 19 "sync/atomic" 20 21 "github.com/zuoyebang/bitalosdb/internal/base" 22 ) 23 24 type flushable interface { 25 get(k []byte) ([]byte, bool, base.InternalKeyKind) 26 newIter(o *IterOptions) internalIterator 27 newFlushIter(o *IterOptions, bytesFlushed *uint64) internalIterator 28 inuseBytes() uint64 29 totalBytes() uint64 30 empty() bool 31 readyForFlush() bool 32 } 33 34 type flushableEntry struct { 35 flushable 36 flushed chan struct{} 37 flushForced bool 38 logNum FileNum 39 logSize uint64 40 logSeqNum uint64 41 readerRefs atomic.Int32 42 releaseMemAccounting func() 43 } 44 45 func (e *flushableEntry) readerRef() { 46 e.readerRefs.Add(1) 47 } 48 49 func (e *flushableEntry) readerUnref() { 50 switch v := e.readerRefs.Add(-1); { 51 case v == 0: 52 if e.releaseMemAccounting == nil { 53 fmt.Println("panic: flushableEntry readerUnref reservation already released") 54 return 55 } 56 e.releaseMemAccounting() 57 e.releaseMemAccounting = nil 58 case v < 0: 59 fmt.Printf("panic: flushableEntry readerUnref logNum:%d count:%d\n", e.logNum, v) 60 } 61 } 62 63 type flushableList []*flushableEntry 64 65 func newFlushableEntry(f flushable, logNum FileNum, logSeqNum uint64) *flushableEntry { 66 entry := &flushableEntry{ 67 flushable: f, 68 flushed: make(chan struct{}), 69 logNum: logNum, 70 logSeqNum: logSeqNum, 71 } 72 entry.readerRefs.Store(1) 73 return entry 74 }