1// Copyright 2020 The Prometheus Authors 2// Licensed under the Apache License, Version 2.0 (the "License"); 3// you may not use this file except in compliance with the License. 4// You may obtain a copy of the License at 5// 6// http://www.apache.org/licenses/LICENSE-2.0 7// 8// Unless required by applicable law or agreed to in writing, software 9// distributed under the License is distributed on an "AS IS" BASIS, 10// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 11// See the License for the specific language governing permissions and 12// limitations under the License. 13 14package procfs 15 16import ( 17 "bufio" 18 "bytes" 19 "fmt" 20 "regexp" 21 "strconv" 22 "strings" 23 24 "github.com/prometheus/procfs/internal/util" 25) 26 27var ( 28 slabSpace = regexp.MustCompile(`\s+`) 29 slabVer = regexp.MustCompile(`slabinfo -`) 30 slabHeader = regexp.MustCompile(`# name`) 31) 32 33// Slab represents a slab pool in the kernel. 34type Slab struct { 35 Name string 36 ObjActive int64 37 ObjNum int64 38 ObjSize int64 39 ObjPerSlab int64 40 PagesPerSlab int64 41 // tunables 42 Limit int64 43 Batch int64 44 SharedFactor int64 45 SlabActive int64 46 SlabNum int64 47 SharedAvail int64 48} 49 50// SlabInfo represents info for all slabs. 51type SlabInfo struct { 52 Slabs []*Slab 53} 54 55func shouldParseSlab(line string) bool { 56 if slabVer.MatchString(line) { 57 return false 58 } 59 if slabHeader.MatchString(line) { 60 return false 61 } 62 return true 63} 64 65// parseV21SlabEntry is used to parse a line from /proc/slabinfo version 2.1. 66func parseV21SlabEntry(line string) (*Slab, error) { 67 // First cleanup whitespace. 68 l := slabSpace.ReplaceAllString(line, " ") 69 s := strings.Split(l, " ") 70 if len(s) != 16 { 71 return nil, fmt.Errorf("unable to parse: %q", line) 72 } 73 var err error 74 i := &Slab{Name: s[0]} 75 i.ObjActive, err = strconv.ParseInt(s[1], 10, 64) 76 if err != nil { 77 return nil, err 78 } 79 i.ObjNum, err = strconv.ParseInt(s[2], 10, 64) 80 if err != nil { 81 return nil, err 82 } 83 i.ObjSize, err = strconv.ParseInt(s[3], 10, 64) 84 if err != nil { 85 return nil, err 86 } 87 i.ObjPerSlab, err = strconv.ParseInt(s[4], 10, 64) 88 if err != nil { 89 return nil, err 90 } 91 i.PagesPerSlab, err = strconv.ParseInt(s[5], 10, 64) 92 if err != nil { 93 return nil, err 94 } 95 i.Limit, err = strconv.ParseInt(s[8], 10, 64) 96 if err != nil { 97 return nil, err 98 } 99 i.Batch, err = strconv.ParseInt(s[9], 10, 64) 100 if err != nil { 101 return nil, err 102 } 103 i.SharedFactor, err = strconv.ParseInt(s[10], 10, 64) 104 if err != nil { 105 return nil, err 106 } 107 i.SlabActive, err = strconv.ParseInt(s[13], 10, 64) 108 if err != nil { 109 return nil, err 110 } 111 i.SlabNum, err = strconv.ParseInt(s[14], 10, 64) 112 if err != nil { 113 return nil, err 114 } 115 i.SharedAvail, err = strconv.ParseInt(s[15], 10, 64) 116 if err != nil { 117 return nil, err 118 } 119 return i, nil 120} 121 122// parseSlabInfo21 is used to parse a slabinfo 2.1 file. 123func parseSlabInfo21(r *bytes.Reader) (SlabInfo, error) { 124 scanner := bufio.NewScanner(r) 125 s := SlabInfo{Slabs: []*Slab{}} 126 for scanner.Scan() { 127 line := scanner.Text() 128 if !shouldParseSlab(line) { 129 continue 130 } 131 slab, err := parseV21SlabEntry(line) 132 if err != nil { 133 return s, err 134 } 135 s.Slabs = append(s.Slabs, slab) 136 } 137 return s, nil 138} 139 140// SlabInfo reads data from /proc/slabinfo 141func (fs FS) SlabInfo() (SlabInfo, error) { 142 // TODO: Consider passing options to allow for parsing different 143 // slabinfo versions. However, slabinfo 2.1 has been stable since 144 // kernel 2.6.10 and later. 145 data, err := util.ReadFileNoStat(fs.proc.Path("slabinfo")) 146 if err != nil { 147 return SlabInfo{}, err 148 } 149 150 return parseSlabInfo21(bytes.NewReader(data)) 151} 152