62 lines
1.4 KiB
Go
62 lines
1.4 KiB
Go
// +build linux
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package fingerprint
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import (
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"fmt"
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cstructs "github.com/hashicorp/nomad/client/structs"
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"github.com/opencontainers/runc/libcontainer/cgroups"
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)
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const (
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cgroupAvailable = "available"
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)
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// FindCgroupMountpointDir is used to find the cgroup mount point on a Linux
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// system.
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func FindCgroupMountpointDir() (string, error) {
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mount, err := cgroups.FindCgroupMountpointDir()
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if err != nil {
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switch e := err.(type) {
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case *cgroups.NotFoundError:
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// It's okay if the mount point is not discovered
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return "", nil
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default:
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// All other errors are passed back as is
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return "", e
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}
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}
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return mount, nil
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}
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// Fingerprint tries to find a valid cgroup mount point
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func (f *CGroupFingerprint) Fingerprint(req *cstructs.FingerprintRequest, resp *cstructs.FingerprintResponse) error {
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mount, err := f.mountPointDetector.MountPoint()
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if err != nil {
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f.clearCGroupAttributes(resp)
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return fmt.Errorf("Failed to discover cgroup mount point: %s", err)
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}
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// Check if a cgroup mount point was found
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if mount == "" {
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f.clearCGroupAttributes(resp)
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if f.lastState == cgroupAvailable {
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f.logger.Info("cgroups are unavailable")
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}
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f.lastState = cgroupUnavailable
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return nil
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}
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resp.AddAttribute("unique.cgroup.mountpoint", mount)
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resp.Detected = true
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if f.lastState == cgroupUnavailable {
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f.logger.Info("cgroups are available")
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}
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f.lastState = cgroupAvailable
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return nil
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}
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