utils: reintroduce moveToCgroup

commit ee62711 introduced the regression. It was mistakenly removed as part of a cleanup, but this code is needed by another code path, where we move conmon for the exec session to the same cgroup used by conmon for the process. Closes: containers#12535 [NO NEW TESTS NEEDED] it fixes a regression in the CI Signed-off-by: Giuseppe Scrivano <[email protected]>
edsantiago · Dec 8, 2021 · 2ddd2b7 · 2ddd2b7
1 parent 49f589d
commit 2ddd2b7
Showing 1 changed file with 9 additions and 0 deletions.
diff --git a/utils/utils_supported.go b/utils/utils_supported.go
@@ -44,6 +44,15 @@ func RunUnderSystemdScope(pid int, slice string, unitName string) error {
 	ch := make(chan string)
 	_, err = conn.StartTransientUnit(unitName, "replace", properties, ch)
 	if err != nil {
+		// On errors check if the cgroup already exists, if it does move the process there
+		if props, err := conn.GetUnitTypeProperties(unitName, "Scope"); err == nil {
+			if cgroup, ok := props["ControlGroup"].(string); ok && cgroup != "" {
+				if err := moveUnderCgroup(cgroup, "", []uint32{uint32(pid)}); err == nil {
+					return nil
+				}
+				// On errors return the original error message we got from StartTransientUnit.
+			}
+		}
 		return err
 	}