From 2f5552c32d01678bfbfdbb8838e1672d62521a6c Mon Sep 17 00:00:00 2001 From: flouthoc Date: Wed, 19 May 2021 01:19:20 +0530 Subject: Podman info add support for status of cgroup controllers Signed-off-by: flouthoc --- docs/source/markdown/podman-info.1.md | 13 +++++ libpod/define/info.go | 31 +++++----- libpod/info.go | 44 ++++++++------ pkg/cgroups/cgroups.go | 106 +++++++++++++++++++++++++++++++--- test/e2e/info_test.go | 10 ++++ 5 files changed, 163 insertions(+), 41 deletions(-) diff --git a/docs/source/markdown/podman-info.1.md b/docs/source/markdown/podman-info.1.md index 4af51d3eb..227fbd92d 100644 --- a/docs/source/markdown/podman-info.1.md +++ b/docs/source/markdown/podman-info.1.md @@ -32,6 +32,12 @@ $ podman info host: arch: amd64 buildahVersion: 1.19.0-dev + cgroupControllers: + - cpuset + - cpu + - io + - memory + - pids cgroupManager: systemd cgroupVersion: v2 conmon: @@ -145,6 +151,13 @@ Run podman info with JSON formatted response: "buildahVersion": "1.19.0-dev", "cgroupManager": "systemd", "cgroupVersion": "v2", + "cgroupControllers": [ + "cpuset", + "cpu", + "io", + "memory", + "pids" + ], "conmon": { "package": "conmon-2.0.22-2.fc33.x86_64", "path": "/usr/bin/conmon", diff --git a/libpod/define/info.go b/libpod/define/info.go index c9d6877c0..de709be74 100644 --- a/libpod/define/info.go +++ b/libpod/define/info.go @@ -23,21 +23,22 @@ type SecurityInfo struct { // HostInfo describes the libpod host type HostInfo struct { - Arch string `json:"arch"` - BuildahVersion string `json:"buildahVersion"` - CgroupManager string `json:"cgroupManager"` - CGroupsVersion string `json:"cgroupVersion"` - Conmon *ConmonInfo `json:"conmon"` - CPUs int `json:"cpus"` - Distribution DistributionInfo `json:"distribution"` - EventLogger string `json:"eventLogger"` - Hostname string `json:"hostname"` - IDMappings IDMappings `json:"idMappings,omitempty"` - Kernel string `json:"kernel"` - MemFree int64 `json:"memFree"` - MemTotal int64 `json:"memTotal"` - OCIRuntime *OCIRuntimeInfo `json:"ociRuntime"` - OS string `json:"os"` + Arch string `json:"arch"` + BuildahVersion string `json:"buildahVersion"` + CgroupManager string `json:"cgroupManager"` + CGroupsVersion string `json:"cgroupVersion"` + CgroupControllers []string `json:"cgroupControllers"` + Conmon *ConmonInfo `json:"conmon"` + CPUs int `json:"cpus"` + Distribution DistributionInfo `json:"distribution"` + EventLogger string `json:"eventLogger"` + Hostname string `json:"hostname"` + IDMappings IDMappings `json:"idMappings,omitempty"` + Kernel string `json:"kernel"` + MemFree int64 `json:"memFree"` + MemTotal int64 `json:"memTotal"` + OCIRuntime *OCIRuntimeInfo `json:"ociRuntime"` + OS string `json:"os"` // RemoteSocket returns the UNIX domain socket the Podman service is listening on RemoteSocket *RemoteSocket `json:"remoteSocket,omitempty"` RuntimeInfo map[string]interface{} `json:"runtimeInfo,omitempty"` diff --git a/libpod/info.go b/libpod/info.go index 7a28a4cf7..461e39a48 100644 --- a/libpod/info.go +++ b/libpod/info.go @@ -93,20 +93,33 @@ func (r *Runtime) hostInfo() (*define.HostInfo, error) { return nil, errors.Wrapf(err, "error getting Seccomp profile path") } + // CGroups version + unified, err := cgroups.IsCgroup2UnifiedMode() + if err != nil { + return nil, errors.Wrapf(err, "error reading cgroups mode") + } + + // Get Map of all available controllers + availableControllers, err := cgroups.GetAvailableControllers(nil, unified) + if err != nil { + return nil, errors.Wrapf(err, "error getting available cgroup controllers") + } + info := define.HostInfo{ - Arch: runtime.GOARCH, - BuildahVersion: buildah.Version, - CgroupManager: r.config.Engine.CgroupManager, - Linkmode: linkmode.Linkmode(), - CPUs: runtime.NumCPU(), - Distribution: hostDistributionInfo, - EventLogger: r.eventer.String(), - Hostname: host, - IDMappings: define.IDMappings{}, - Kernel: kv, - MemFree: mi.MemFree, - MemTotal: mi.MemTotal, - OS: runtime.GOOS, + Arch: runtime.GOARCH, + BuildahVersion: buildah.Version, + CgroupManager: r.config.Engine.CgroupManager, + CgroupControllers: availableControllers, + Linkmode: linkmode.Linkmode(), + CPUs: runtime.NumCPU(), + Distribution: hostDistributionInfo, + EventLogger: r.eventer.String(), + Hostname: host, + IDMappings: define.IDMappings{}, + Kernel: kv, + MemFree: mi.MemFree, + MemTotal: mi.MemTotal, + OS: runtime.GOOS, Security: define.SecurityInfo{ AppArmorEnabled: apparmor.IsEnabled(), DefaultCapabilities: strings.Join(r.config.Containers.DefaultCapabilities, ","), @@ -120,11 +133,6 @@ func (r *Runtime) hostInfo() (*define.HostInfo, error) { SwapTotal: mi.SwapTotal, } - // CGroups version - unified, err := cgroups.IsCgroup2UnifiedMode() - if err != nil { - return nil, errors.Wrapf(err, "error reading cgroups mode") - } cgroupVersion := "v1" if unified { cgroupVersion = "v2" diff --git a/pkg/cgroups/cgroups.go b/pkg/cgroups/cgroups.go index aefb5183b..911edeb5b 100644 --- a/pkg/cgroups/cgroups.go +++ b/pkg/cgroups/cgroups.go @@ -128,28 +128,118 @@ func init() { // getAvailableControllers get the available controllers func getAvailableControllers(exclude map[string]controllerHandler, cgroup2 bool) ([]controller, error) { if cgroup2 { - return nil, fmt.Errorf("getAvailableControllers not implemented yet for cgroup v2") + controllers := []controller{} + subtreeControl := cgroupRoot + "/cgroup.subtree_control" + // rootless cgroupv2: check available controllers for current user ,systemd or servicescope will inherit + if rootless.IsRootless() { + userSlice, err := getCgroupPathForCurrentProcess() + if err != nil { + return controllers, err + } + //userSlice already contains '/' so not adding here + basePath := cgroupRoot + userSlice + subtreeControl = fmt.Sprintf("%s/cgroup.subtree_control", basePath) + } + subtreeControlBytes, err := ioutil.ReadFile(subtreeControl) + if err != nil { + return nil, errors.Wrapf(err, "failed while reading controllers for cgroup v2 from %q", subtreeControl) + } + for _, controllerName := range strings.Fields(string(subtreeControlBytes)) { + c := controller{ + name: controllerName, + symlink: false, + } + controllers = append(controllers, c) + } + return controllers, nil } - infos, err := ioutil.ReadDir(cgroupRoot) - if err != nil { - return nil, err - } + subsystems, _ := cgroupV1GetAllSubsystems() controllers := []controller{} - for _, i := range infos { - name := i.Name() + // cgroupv1 and rootless: No subsystem is available: delegation is unsafe. + if rootless.IsRootless() { + return controllers, nil + } + + for _, name := range subsystems { if _, found := exclude[name]; found { continue } + isSymLink := false + fileInfo, err := os.Stat(cgroupRoot + "/" + name) + if err != nil { + isSymLink = !fileInfo.IsDir() + } c := controller{ name: name, - symlink: !i.IsDir(), + symlink: isSymLink, } controllers = append(controllers, c) } + return controllers, nil } +// GetAvailableControllers get string:bool map of all the available controllers +func GetAvailableControllers(exclude map[string]controllerHandler, cgroup2 bool) ([]string, error) { + availableControllers, err := getAvailableControllers(exclude, cgroup2) + if err != nil { + return nil, err + } + controllerList := []string{} + for _, controller := range availableControllers { + controllerList = append(controllerList, controller.name) + } + + return controllerList, nil +} + +func cgroupV1GetAllSubsystems() ([]string, error) { + f, err := os.Open("/proc/cgroups") + if err != nil { + return nil, err + } + defer f.Close() + + subsystems := []string{} + + s := bufio.NewScanner(f) + for s.Scan() { + text := s.Text() + if text[0] != '#' { + parts := strings.Fields(text) + if len(parts) >= 4 && parts[3] != "0" { + subsystems = append(subsystems, parts[0]) + } + } + } + if err := s.Err(); err != nil { + return nil, err + } + return subsystems, nil +} + +func getCgroupPathForCurrentProcess() (string, error) { + path := fmt.Sprintf("/proc/%d/cgroup", os.Getpid()) + f, err := os.Open(path) + if err != nil { + return "", err + } + defer f.Close() + + cgroupPath := "" + s := bufio.NewScanner(f) + for s.Scan() { + text := s.Text() + procEntries := strings.SplitN(text, "::", 2) + cgroupPath = procEntries[1] + } + if err := s.Err(); err != nil { + return cgroupPath, err + } + return cgroupPath, nil +} + // getCgroupv1Path is a helper function to get the cgroup v1 path func (c *CgroupControl) getCgroupv1Path(name string) string { return filepath.Join(cgroupRoot, name, c.path) diff --git a/test/e2e/info_test.go b/test/e2e/info_test.go index 60136bcc2..f5b70d6bf 100644 --- a/test/e2e/info_test.go +++ b/test/e2e/info_test.go @@ -135,4 +135,14 @@ var _ = Describe("Podman Info", func() { Expect(session.OutputToString()).To(ContainSubstring("false")) } }) + + It("Podman info must contain cgroupControllers with ReleventControllers", func() { + SkipIfRootless("Hard to tell which controllers are going to be enabled for rootless") + SkipIfRootlessCgroupsV1("Disable cgroups not supported on cgroupv1 for rootless users") + session := podmanTest.Podman([]string{"info", "--format", "{{.Host.CgroupControllers}}"}) + session.WaitWithDefaultTimeout() + Expect(session).To(Exit(0)) + Expect(session.OutputToString()).To(ContainSubstring("memory")) + Expect(session.OutputToString()).To(ContainSubstring("pids")) + }) }) -- cgit v1.2.3-54-g00ecf