diff --git a/src/basic/cgroup-util.c b/src/basic/cgroup-util.c index 289e4fe073a..95bf177a6bd 100644 --- a/src/basic/cgroup-util.c +++ b/src/basic/cgroup-util.c @@ -1688,6 +1688,30 @@ int cg_slice_to_path(const char *unit, char **ret) { return 0; } +int cg_is_threaded(const char *controller, const char *path) { + _cleanup_free_ char *fs = NULL, *contents = NULL; + _cleanup_strv_free_ char **v = NULL; + int r; + + r = cg_get_path(controller, path, "cgroup.type", &fs); + if (r < 0) + return r; + + r = read_full_virtual_file(fs, &contents, NULL); + if (r == -ENOENT) + return false; /* Assume no. */ + if (r < 0) + return r; + + v = strv_split(contents, NULL); + if (!v) + return -ENOMEM; + + /* If the cgroup is in the threaded mode, it contains "threaded". + * If one of the parents or siblings is in the threaded mode, it may contain "invalid". */ + return strv_contains(v, "threaded") || strv_contains(v, "invalid"); +} + int cg_set_attribute(const char *controller, const char *path, const char *attribute, const char *value) { _cleanup_free_ char *p = NULL; int r; diff --git a/src/basic/cgroup-util.h b/src/basic/cgroup-util.h index 461c01b3c20..4c413a8d174 100644 --- a/src/basic/cgroup-util.h +++ b/src/basic/cgroup-util.h @@ -205,6 +205,8 @@ int cg_pid_get_path(const char *controller, pid_t pid, char **path); int cg_rmdir(const char *controller, const char *path); +int cg_is_threaded(const char *controller, const char *path); + typedef enum { CG_KEY_MODE_GRACEFUL = 1 << 0, } CGroupKeyMode;