X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;ds=inline;f=src%2Fcgroup-util.c;h=fd0ac98e28faad081e1b2faa17425b592f2e9ea7;hb=3bfc71846c3eac9011f0182b0c8d5639a9549228;hp=bbadc789a1651a30a2d995c85f807c704dc41b84;hpb=1f73f0f163eeb8a889e3799c0c63bcb437e531ac;p=elogind.git

diff --git a/src/cgroup-util.c b/src/cgroup-util.c
index bbadc789a..fd0ac98e2 100644
--- a/src/cgroup-util.c
+++ b/src/cgroup-util.c
@@ -482,12 +482,26 @@ finish:
 
 int cg_get_path(const char *controller, const char *path, const char *suffix, char **fs) {
         const char *p;
-        char *mp;
-        int r;
+        char *t;
+        static __thread bool good = false;
 
         assert(controller);
         assert(fs);
 
+        if (_unlikely_(!good)) {
+                int r;
+
+                r = path_is_mount_point("/sys/fs/cgroup");
+                if (r <= 0)
+                        return r < 0 ? r : -ENOENT;
+
+                /* Cache this to save a few stat()s */
+                good = true;
+        }
+
+        if (isempty(controller))
+                return -EINVAL;
+
         /* This is a very minimal lookup from controller names to
          * paths. Since we have mounted most hierarchies ourselves
          * should be kinda safe, but eventually we might want to
@@ -501,29 +515,22 @@ int cg_get_path(const char *controller, const char *path, const char *suffix, ch
         else
                 p = controller;
 
-        if (asprintf(&mp, "/sys/fs/cgroup/%s", p) < 0)
-                return -ENOMEM;
-
-        if ((r = path_is_mount_point(mp)) <= 0) {
-                free(mp);
-                return r < 0 ? r : -ENOENT;
-        }
-
         if (path && suffix)
-                r = asprintf(fs, "%s/%s/%s", mp, path, suffix);
+                t = join("/sys/fs/cgroup/", p, "/", path, "/", suffix, NULL);
         else if (path)
-                r = asprintf(fs, "%s/%s", mp, path);
+                t = join("/sys/fs/cgroup/", p, "/", path, NULL);
         else if (suffix)
-                r = asprintf(fs, "%s/%s", mp, suffix);
-        else {
-                path_kill_slashes(mp);
-                *fs = mp;
-                return 0;
-        }
+                t = join("/sys/fs/cgroup/", p, "/", suffix, NULL);
+        else
+                t = join("/sys/fs/cgroup/", p, NULL);
+
+        if (!t)
+                return -ENOMEM;
 
-        free(mp);
-        path_kill_slashes(*fs);
-        return r < 0 ? -ENOMEM : 0;
+        path_kill_slashes(t);
+
+        *fs = t;
+        return 0;
 }
 
 int cg_trim(const char *controller, const char *path, bool delete_root) {