diff --git a/man/sd_booted.xml b/man/sd_booted.xml
index 34f2cbfbc..ce5a34dc8 100644
--- a/man/sd_booted.xml
+++ b/man/sd_booted.xml
@@ -85,11 +85,10 @@
                 implementation.</para>
 
                 <para>Internally, this function checks whether the
-                <filename>/sys/fs/cgroup/systemd</filename> virtual file
-                system is mounted, by comparing the st_dev value of
-                the <function>stat()</function> data of
-                <filename>/sys/fs/cgroup</filename> and
-                <filename>/sys/fs/cgroup/systemd</filename>.</para>
+                directory <filename>/run/systemd/system/</filename>
+                exists. A simple check like this can also be
+                implemented trivially in shell or any other
+                language.</para>
 
                 <para>For details about the algorithm check the
                 liberally licensed reference implementation sources:
diff --git a/src/core/mount-setup.c b/src/core/mount-setup.c
index 42cdc6dc5..ce10be944 100644
--- a/src/core/mount-setup.c
+++ b/src/core/mount-setup.c
@@ -440,7 +440,11 @@ int mount_setup(bool loaded_policy) {
                 if (mount(NULL, "/", NULL, MS_REC|MS_SHARED, NULL) < 0)
                         log_warning("Failed to set up the root directory for shared mount propagation: %m");
 
-        /* Create a few directories we always want around */
+        /* Create a few directories we always want around, Note that
+         * sd_booted() checks for /run/systemd/system, so this mkdir
+         * really needs to stay for good, otherwise software that
+         * copied sd-daemon.c into their sources will misdetect
+         * systemd. */
         mkdir_label("/run/systemd", 0755);
         mkdir_label("/run/systemd/system", 0755);
 
diff --git a/src/libsystemd-daemon/sd-daemon.c b/src/libsystemd-daemon/sd-daemon.c
index 5b92e2e3d..79d8ca370 100644
--- a/src/libsystemd-daemon/sd-daemon.c
+++ b/src/libsystemd-daemon/sd-daemon.c
@@ -519,18 +519,15 @@ _sd_export_ int sd_booted(void) {
 #if defined(DISABLE_SYSTEMD) || !defined(__linux__)
         return 0;
 #else
+        struct stat st;
 
-        struct stat a, b;
+        /* We test whether the runtime unit file directory has been
+         * created. This takes place in mount-setup.c, so is
+         * guaranteed to happen very early during boot. */
 
-        /* We simply test whether the systemd cgroup hierarchy is
-         * mounted */
-
-        if (lstat("/sys/fs/cgroup", &a) < 0)
+        if (lstat("/run/systemd/system/", &st) < 0)
                 return 0;
 
-        if (lstat("/sys/fs/cgroup/systemd", &b) < 0)
-                return 0;
-
-        return a.st_dev != b.st_dev;
+        return !!S_ISDIR(st.st_mode);
 #endif
 }