1// Copyright 2019 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 "io" 21 "strconv" 22 "strings" 23 24 "github.com/prometheus/procfs/internal/util" 25) 26 27// For the proc file format details, 28// See: 29// * Linux 2.6.23 https://elixir.bootlin.com/linux/v2.6.23/source/net/core/dev.c#L2343 30// * Linux 4.17 https://elixir.bootlin.com/linux/v4.17/source/net/core/net-procfs.c#L162 31// and https://elixir.bootlin.com/linux/v4.17/source/include/linux/netdevice.h#L2810. 32 33// SoftnetStat contains a single row of data from /proc/net/softnet_stat 34type SoftnetStat struct { 35 // Number of processed packets 36 Processed uint32 37 // Number of dropped packets 38 Dropped uint32 39 // Number of times processing packets ran out of quota 40 TimeSqueezed uint32 41} 42 43var softNetProcFile = "net/softnet_stat" 44 45// NetSoftnetStat reads data from /proc/net/softnet_stat. 46func (fs FS) NetSoftnetStat() ([]SoftnetStat, error) { 47 b, err := util.ReadFileNoStat(fs.proc.Path(softNetProcFile)) 48 if err != nil { 49 return nil, err 50 } 51 52 entries, err := parseSoftnet(bytes.NewReader(b)) 53 if err != nil { 54 return nil, fmt.Errorf("failed to parse /proc/net/softnet_stat: %w", err) 55 } 56 57 return entries, nil 58} 59 60func parseSoftnet(r io.Reader) ([]SoftnetStat, error) { 61 const minColumns = 9 62 63 s := bufio.NewScanner(r) 64 65 var stats []SoftnetStat 66 for s.Scan() { 67 columns := strings.Fields(s.Text()) 68 width := len(columns) 69 70 if width < minColumns { 71 return nil, fmt.Errorf("%d columns were detected, but at least %d were expected", width, minColumns) 72 } 73 74 // We only parse the first three columns at the moment. 75 us, err := parseHexUint32s(columns[0:3]) 76 if err != nil { 77 return nil, err 78 } 79 80 stats = append(stats, SoftnetStat{ 81 Processed: us[0], 82 Dropped: us[1], 83 TimeSqueezed: us[2], 84 }) 85 } 86 87 return stats, nil 88} 89 90func parseHexUint32s(ss []string) ([]uint32, error) { 91 us := make([]uint32, 0, len(ss)) 92 for _, s := range ss { 93 u, err := strconv.ParseUint(s, 16, 32) 94 if err != nil { 95 return nil, err 96 } 97 98 us = append(us, uint32(u)) 99 } 100 101 return us, nil 102} 103