| // Copyright 2017 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 sysfs |
| |
| import ( |
| "fmt" |
| "os" |
| "path/filepath" |
| |
| "github.com/prometheus/procfs/bcache" |
| "github.com/prometheus/procfs/xfs" |
| ) |
| |
| // FS represents the pseudo-filesystem sys, which provides an interface to |
| // kernel data structures. |
| type FS string |
| |
| // DefaultMountPoint is the common mount point of the sys filesystem. |
| const DefaultMountPoint = "/sys" |
| |
| // NewFS returns a new FS mounted under the given mountPoint. It will error |
| // if the mount point can't be read. |
| func NewFS(mountPoint string) (FS, error) { |
| info, err := os.Stat(mountPoint) |
| if err != nil { |
| return "", fmt.Errorf("could not read %s: %s", mountPoint, err) |
| } |
| if !info.IsDir() { |
| return "", fmt.Errorf("mount point %s is not a directory", mountPoint) |
| } |
| |
| return FS(mountPoint), nil |
| } |
| |
| // Path returns the path of the given subsystem relative to the sys root. |
| func (fs FS) Path(p ...string) string { |
| return filepath.Join(append([]string{string(fs)}, p...)...) |
| } |
| |
| // XFSStats retrieves XFS filesystem runtime statistics for each mounted XFS |
| // filesystem. Only available on kernel 4.4+. On older kernels, an empty |
| // slice of *xfs.Stats will be returned. |
| func (fs FS) XFSStats() ([]*xfs.Stats, error) { |
| matches, err := filepath.Glob(fs.Path("fs/xfs/*/stats/stats")) |
| if err != nil { |
| return nil, err |
| } |
| |
| stats := make([]*xfs.Stats, 0, len(matches)) |
| for _, m := range matches { |
| f, err := os.Open(m) |
| if err != nil { |
| return nil, err |
| } |
| |
| // "*" used in glob above indicates the name of the filesystem. |
| name := filepath.Base(filepath.Dir(filepath.Dir(m))) |
| |
| // File must be closed after parsing, regardless of success or |
| // failure. Defer is not used because of the loop. |
| s, err := xfs.ParseStats(f) |
| _ = f.Close() |
| if err != nil { |
| return nil, err |
| } |
| |
| s.Name = name |
| stats = append(stats, s) |
| } |
| |
| return stats, nil |
| } |
| |
| // BcacheStats retrieves bcache runtime statistics for each bcache. |
| func (fs FS) BcacheStats() ([]*bcache.Stats, error) { |
| matches, err := filepath.Glob(fs.Path("fs/bcache/*-*")) |
| if err != nil { |
| return nil, err |
| } |
| |
| stats := make([]*bcache.Stats, 0, len(matches)) |
| for _, uuidPath := range matches { |
| // "*-*" in glob above indicates the name of the bcache. |
| name := filepath.Base(uuidPath) |
| |
| // stats |
| s, err := bcache.GetStats(uuidPath) |
| if err != nil { |
| return nil, err |
| } |
| |
| s.Name = name |
| stats = append(stats, s) |
| } |
| |
| return stats, nil |
| } |