DockerCLI/vendor/github.com/prometheus/procfs/mdstat.go

195 lines
5.6 KiB
Go

// Copyright 2018 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 (
"fmt"
"io/ioutil"
"regexp"
"strconv"
"strings"
)
var (
statusLineRE = regexp.MustCompile(`(\d+) blocks .*\[(\d+)/(\d+)\] \[[U_]+\]`)
recoveryLineRE = regexp.MustCompile(`\((\d+)/\d+\)`)
)
// MDStat holds info parsed from /proc/mdstat.
type MDStat struct {
// Name of the device.
Name string
// activity-state of the device.
ActivityState string
// Number of active disks.
DisksActive int64
// Total number of disks the device requires.
DisksTotal int64
// Number of failed disks.
DisksFailed int64
// Spare disks in the device.
DisksSpare int64
// Number of blocks the device holds.
BlocksTotal int64
// Number of blocks on the device that are in sync.
BlocksSynced int64
}
// MDStat parses an mdstat-file (/proc/mdstat) and returns a slice of
// structs containing the relevant info. More information available here:
// https://raid.wiki.kernel.org/index.php/Mdstat
func (fs FS) MDStat() ([]MDStat, error) {
data, err := ioutil.ReadFile(fs.proc.Path("mdstat"))
if err != nil {
return nil, fmt.Errorf("error parsing mdstat %s: %s", fs.proc.Path("mdstat"), err)
}
mdstat, err := parseMDStat(data)
if err != nil {
return nil, fmt.Errorf("error parsing mdstat %s: %s", fs.proc.Path("mdstat"), err)
}
return mdstat, nil
}
// parseMDStat parses data from mdstat file (/proc/mdstat) and returns a slice of
// structs containing the relevant info.
func parseMDStat(mdStatData []byte) ([]MDStat, error) {
mdStats := []MDStat{}
lines := strings.Split(string(mdStatData), "\n")
for i, line := range lines {
if strings.TrimSpace(line) == "" || line[0] == ' ' ||
strings.HasPrefix(line, "Personalities") ||
strings.HasPrefix(line, "unused") {
continue
}
deviceFields := strings.Fields(line)
if len(deviceFields) < 3 {
return nil, fmt.Errorf("not enough fields in mdline (expected at least 3): %s", line)
}
mdName := deviceFields[0] // mdx
state := deviceFields[2] // active or inactive
if len(lines) <= i+3 {
return nil, fmt.Errorf(
"error parsing %s: too few lines for md device",
mdName,
)
}
// Failed disks have the suffix (F) & Spare disks have the suffix (S).
fail := int64(strings.Count(line, "(F)"))
spare := int64(strings.Count(line, "(S)"))
active, total, size, err := evalStatusLine(lines[i], lines[i+1])
if err != nil {
return nil, fmt.Errorf("error parsing md device lines: %s", err)
}
syncLineIdx := i + 2
if strings.Contains(lines[i+2], "bitmap") { // skip bitmap line
syncLineIdx++
}
// If device is syncing at the moment, get the number of currently
// synced bytes, otherwise that number equals the size of the device.
syncedBlocks := size
recovering := strings.Contains(lines[syncLineIdx], "recovery")
resyncing := strings.Contains(lines[syncLineIdx], "resync")
// Append recovery and resyncing state info.
if recovering || resyncing {
if recovering {
state = "recovering"
} else {
state = "resyncing"
}
// Handle case when resync=PENDING or resync=DELAYED.
if strings.Contains(lines[syncLineIdx], "PENDING") ||
strings.Contains(lines[syncLineIdx], "DELAYED") {
syncedBlocks = 0
} else {
syncedBlocks, err = evalRecoveryLine(lines[syncLineIdx])
if err != nil {
return nil, fmt.Errorf("error parsing sync line in md device %s: %s", mdName, err)
}
}
}
mdStats = append(mdStats, MDStat{
Name: mdName,
ActivityState: state,
DisksActive: active,
DisksFailed: fail,
DisksSpare: spare,
DisksTotal: total,
BlocksTotal: size,
BlocksSynced: syncedBlocks,
})
}
return mdStats, nil
}
func evalStatusLine(deviceLine, statusLine string) (active, total, size int64, err error) {
sizeStr := strings.Fields(statusLine)[0]
size, err = strconv.ParseInt(sizeStr, 10, 64)
if err != nil {
return 0, 0, 0, fmt.Errorf("unexpected statusLine %s: %s", statusLine, err)
}
if strings.Contains(deviceLine, "raid0") || strings.Contains(deviceLine, "linear") {
// In the device deviceLine, only disks have a number associated with them in [].
total = int64(strings.Count(deviceLine, "["))
return total, total, size, nil
}
if strings.Contains(deviceLine, "inactive") {
return 0, 0, size, nil
}
matches := statusLineRE.FindStringSubmatch(statusLine)
if len(matches) != 4 {
return 0, 0, 0, fmt.Errorf("couldn't find all the substring matches: %s", statusLine)
}
total, err = strconv.ParseInt(matches[2], 10, 64)
if err != nil {
return 0, 0, 0, fmt.Errorf("unexpected statusLine %s: %s", statusLine, err)
}
active, err = strconv.ParseInt(matches[3], 10, 64)
if err != nil {
return 0, 0, 0, fmt.Errorf("unexpected statusLine %s: %s", statusLine, err)
}
return active, total, size, nil
}
func evalRecoveryLine(recoveryLine string) (syncedBlocks int64, err error) {
matches := recoveryLineRE.FindStringSubmatch(recoveryLine)
if len(matches) != 2 {
return 0, fmt.Errorf("unexpected recoveryLine: %s", recoveryLine)
}
syncedBlocks, err = strconv.ParseInt(matches[1], 10, 64)
if err != nil {
return 0, fmt.Errorf("%s in recoveryLine: %s", err, recoveryLine)
}
return syncedBlocks, nil
}