cloudflared-mirror/vendor/github.com/prometheus/procfs/slab.go

152 lines
3.5 KiB
Go

// Copyright 2020 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package procfs
import (
"bufio"
"bytes"
"fmt"
"regexp"
"strconv"
"strings"
"github.com/prometheus/procfs/internal/util"
)
var (
slabSpace = regexp.MustCompile(`\s+`)
slabVer = regexp.MustCompile(`slabinfo -`)
slabHeader = regexp.MustCompile(`# name`)
)
// Slab represents a slab pool in the kernel.
type Slab struct {
Name string
ObjActive int64
ObjNum int64
ObjSize int64
ObjPerSlab int64
PagesPerSlab int64
// tunables
Limit int64
Batch int64
SharedFactor int64
SlabActive int64
SlabNum int64
SharedAvail int64
}
// SlabInfo represents info for all slabs.
type SlabInfo struct {
Slabs []*Slab
}
func shouldParseSlab(line string) bool {
if slabVer.MatchString(line) {
return false
}
if slabHeader.MatchString(line) {
return false
}
return true
}
// parseV21SlabEntry is used to parse a line from /proc/slabinfo version 2.1.
func parseV21SlabEntry(line string) (*Slab, error) {
// First cleanup whitespace.
l := slabSpace.ReplaceAllString(line, " ")
s := strings.Split(l, " ")
if len(s) != 16 {
return nil, fmt.Errorf("unable to parse: %q", line)
}
var err error
i := &Slab{Name: s[0]}
i.ObjActive, err = strconv.ParseInt(s[1], 10, 64)
if err != nil {
return nil, err
}
i.ObjNum, err = strconv.ParseInt(s[2], 10, 64)
if err != nil {
return nil, err
}
i.ObjSize, err = strconv.ParseInt(s[3], 10, 64)
if err != nil {
return nil, err
}
i.ObjPerSlab, err = strconv.ParseInt(s[4], 10, 64)
if err != nil {
return nil, err
}
i.PagesPerSlab, err = strconv.ParseInt(s[5], 10, 64)
if err != nil {
return nil, err
}
i.Limit, err = strconv.ParseInt(s[8], 10, 64)
if err != nil {
return nil, err
}
i.Batch, err = strconv.ParseInt(s[9], 10, 64)
if err != nil {
return nil, err
}
i.SharedFactor, err = strconv.ParseInt(s[10], 10, 64)
if err != nil {
return nil, err
}
i.SlabActive, err = strconv.ParseInt(s[13], 10, 64)
if err != nil {
return nil, err
}
i.SlabNum, err = strconv.ParseInt(s[14], 10, 64)
if err != nil {
return nil, err
}
i.SharedAvail, err = strconv.ParseInt(s[15], 10, 64)
if err != nil {
return nil, err
}
return i, nil
}
// parseSlabInfo21 is used to parse a slabinfo 2.1 file.
func parseSlabInfo21(r *bytes.Reader) (SlabInfo, error) {
scanner := bufio.NewScanner(r)
s := SlabInfo{Slabs: []*Slab{}}
for scanner.Scan() {
line := scanner.Text()
if !shouldParseSlab(line) {
continue
}
slab, err := parseV21SlabEntry(line)
if err != nil {
return s, err
}
s.Slabs = append(s.Slabs, slab)
}
return s, nil
}
// SlabInfo reads data from /proc/slabinfo
func (fs FS) SlabInfo() (SlabInfo, error) {
// TODO: Consider passing options to allow for parsing different
// slabinfo versions. However, slabinfo 2.1 has been stable since
// kernel 2.6.10 and later.
data, err := util.ReadFileNoStat(fs.proc.Path("slabinfo"))
if err != nil {
return SlabInfo{}, err
}
return parseSlabInfo21(bytes.NewReader(data))
}