Files
tidb/pkg/util/cgroup/cgroup_cpu_linux.go
2024-04-15 14:51:06 +00:00

101 lines
2.9 KiB
Go

// Copyright 2022 PingCAP, Inc.
//
// 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.
//go:build linux
package cgroup
import (
"math"
"os"
"runtime"
"strings"
"github.com/pingcap/errors"
"github.com/pingcap/failpoint"
)
// GetCgroupCPU returns the CPU usage and quota for the current cgroup.
func GetCgroupCPU() (CPUUsage, error) {
failpoint.Inject("GetCgroupCPUErr", func(val failpoint.Value) {
//nolint:forcetypeassert
if val.(bool) {
var cpuUsage CPUUsage
failpoint.Return(cpuUsage, errors.Errorf("mockAddBatchDDLJobsErr"))
}
})
cpuusage, err := getCgroupCPU("/")
cpuusage.NumCPU = runtime.NumCPU()
return cpuusage, err
}
// CPUQuotaToGOMAXPROCS converts the CPU quota applied to the calling process
// to a valid GOMAXPROCS value.
func CPUQuotaToGOMAXPROCS(minValue int) (int, CPUQuotaStatus, error) {
quota, err := GetCgroupCPU()
if err != nil {
return -1, CPUQuotaUndefined, err
}
maxProcs := int(math.Ceil(quota.CPUShares()))
if minValue > 0 && maxProcs < minValue {
return minValue, CPUQuotaMinUsed, nil
}
return maxProcs, CPUQuotaUsed, nil
}
// GetCPUPeriodAndQuota returns CPU period and quota time of cgroup.
func GetCPUPeriodAndQuota() (period int64, quota int64, err error) {
return getCgroupCPUPeriodAndQuota("/")
}
// InContainer returns true if the process is running in a container.
func InContainer() bool {
// for cgroup V1, check /proc/self/cgroup, for V2, check /proc/self/mountinfo
return inContainer(procPathCGroup) || inContainer(procPathMountInfo)
}
func inContainer(path string) bool {
v, err := os.ReadFile(path)
if err != nil {
return false
}
// For cgroup V1, check /proc/self/cgroup
if path == procPathCGroup {
if strings.Contains(string(v), "docker") ||
strings.Contains(string(v), "kubepods") ||
strings.Contains(string(v), "containerd") {
return true
}
}
// For cgroup V2, check /proc/self/mountinfo
if path == procPathMountInfo {
lines := strings.Split(string(v), "\n")
for _, line := range lines {
v := strings.Split(line, " ")
// check mount point of root dir is on overlay or not.
// v[4] means `mount point`, v[8] means `filesystem type`.
// see details from https://man7.org/linux/man-pages/man5/proc.5.html
// TODO: enhance this check, as overlay is not the only storage driver for container.
if len(v) > 8 && v[4] == "/" && v[8] == "overlay" {
return true
}
}
}
return false
}