| From 27df92a0f9741b26c2f7c57a16047531edbbeed9 Mon Sep 17 00:00:00 2001 |
| From: Filipe Brandenburger <filbranden@gmail.com> |
| Date: Thu, 22 Aug 2019 21:53:24 -0700 |
| Subject: [PATCH] Remove libcontainer detection for systemd features |
| |
| Transient units (and transient slice units) have been available for quite a |
| long time and RHEL 7 with systemd v219 (likely the oldest OS we care about at |
| this point) supports that. A system running a systemd without these features is |
| likely to break a lot of other stuff that runc/libcontainer care about. |
| |
| Regarding delegated slices, modern systemd doesn't allow it and |
| runc/libcontainer run fine on it, so we might as well just stop requesting it |
| on older versions of systemd which allowed it. (Those versions never really |
| changed behavior significantly when that option was passed anyways.) |
| |
| Signed-off-by: Filipe Brandenburger <filbranden@gmail.com> |
| --- |
| libcontainer/cgroups/systemd/apply_systemd.go | 79 +------------------ |
| 1 file changed, 4 insertions(+), 75 deletions(-) |
| |
| diff --git a/libcontainer/cgroups/systemd/apply_systemd.go b/libcontainer/cgroups/systemd/apply_systemd.go |
| index a10e3f6a..15326603 100644 |
| --- a/libcontainer/cgroups/systemd/apply_systemd.go |
| +++ b/libcontainer/cgroups/systemd/apply_systemd.go |
| @@ -72,11 +72,8 @@ const ( |
| ) |
| |
| var ( |
| - connLock sync.Mutex |
| - theConn *systemdDbus.Conn |
| - hasStartTransientUnit bool |
| - hasStartTransientSliceUnit bool |
| - hasDelegateSlice bool |
| + connLock sync.Mutex |
| + theConn *systemdDbus.Conn |
| ) |
| |
| func newProp(name string, units interface{}) systemdDbus.Property { |
| @@ -100,67 +97,8 @@ func UseSystemd() bool { |
| if err != nil { |
| return false |
| } |
| - |
| - // Assume we have StartTransientUnit |
| - hasStartTransientUnit = true |
| - |
| - // But if we get UnknownMethod error we don't |
| - if _, err := theConn.StartTransientUnit("test.scope", "invalid", nil, nil); err != nil { |
| - if dbusError, ok := err.(dbus.Error); ok { |
| - if dbusError.Name == "org.freedesktop.DBus.Error.UnknownMethod" { |
| - hasStartTransientUnit = false |
| - return hasStartTransientUnit |
| - } |
| - } |
| - } |
| - |
| - // Assume we have the ability to start a transient unit as a slice |
| - // This was broken until systemd v229, but has been back-ported on RHEL environments >= 219 |
| - // For details, see: https://bugzilla.redhat.com/show_bug.cgi?id=1370299 |
| - hasStartTransientSliceUnit = true |
| - |
| - // To ensure simple clean-up, we create a slice off the root with no hierarchy |
| - slice := fmt.Sprintf("libcontainer_%d_systemd_test_default.slice", os.Getpid()) |
| - if _, err := theConn.StartTransientUnit(slice, "replace", nil, nil); err != nil { |
| - if _, ok := err.(dbus.Error); ok { |
| - hasStartTransientSliceUnit = false |
| - } |
| - } |
| - |
| - for i := 0; i <= testSliceWait; i++ { |
| - if _, err := theConn.StopUnit(slice, "replace", nil); err != nil { |
| - if dbusError, ok := err.(dbus.Error); ok { |
| - if strings.Contains(dbusError.Name, "org.freedesktop.systemd1.NoSuchUnit") { |
| - hasStartTransientSliceUnit = false |
| - break |
| - } |
| - } |
| - } else { |
| - break |
| - } |
| - time.Sleep(time.Millisecond) |
| - } |
| - |
| - // Not critical because of the stop unit logic above. |
| - theConn.StopUnit(slice, "replace", nil) |
| - |
| - // Assume StartTransientUnit on a slice allows Delegate |
| - hasDelegateSlice = true |
| - dlSlice := newProp("Delegate", true) |
| - if _, err := theConn.StartTransientUnit(slice, "replace", []systemdDbus.Property{dlSlice}, nil); err != nil { |
| - if dbusError, ok := err.(dbus.Error); ok { |
| - // Starting with systemd v237, Delegate is not even a property of slices anymore, |
| - // so the D-Bus call fails with "InvalidArgs" error. |
| - if strings.Contains(dbusError.Name, "org.freedesktop.DBus.Error.PropertyReadOnly") || strings.Contains(dbusError.Name, "org.freedesktop.DBus.Error.InvalidArgs") { |
| - hasDelegateSlice = false |
| - } |
| - } |
| - } |
| - |
| - // Not critical because of the stop unit logic above. |
| - theConn.StopUnit(slice, "replace", nil) |
| } |
| - return hasStartTransientUnit |
| + return true |
| } |
| |
| func (m *Manager) Apply(pid int) error { |
| @@ -196,10 +134,6 @@ func (m *Manager) Apply(pid int) error { |
| |
| // if we create a slice, the parent is defined via a Wants= |
| if strings.HasSuffix(unitName, ".slice") { |
| - // This was broken until systemd v229, but has been back-ported on RHEL environments >= 219 |
| - if !hasStartTransientSliceUnit { |
| - return fmt.Errorf("systemd version does not support ability to start a slice as transient unit") |
| - } |
| properties = append(properties, systemdDbus.PropWants(slice)) |
| } else { |
| // otherwise, we use Slice= |
| @@ -212,12 +146,7 @@ func (m *Manager) Apply(pid int) error { |
| } |
| |
| // Check if we can delegate. This is only supported on systemd versions 218 and above. |
| - if strings.HasSuffix(unitName, ".slice") { |
| - if hasDelegateSlice { |
| - // systemd 237 and above no longer allows delegation on a slice |
| - properties = append(properties, newProp("Delegate", true)) |
| - } |
| - } else { |
| + if !strings.HasSuffix(unitName, ".slice") { |
| // Assume scopes always support delegation. |
| properties = append(properties, newProp("Delegate", true)) |
| } |
| -- |
| 2.23.0.351.gc4317032e6-goog |
| |
