base/init: removed rd.timestamp and automatically export RD_*

dracut.kernel.7.xml

@@ -169,14 +169,6 @@ This parameter can be specified multiple times.</para>
             <para>set udev to loglevel debug</para>
           </listitem>
         </varlistentry>
-        <varlistentry>
-          <term>
-            <envar>rd.timestamp</envar>
-          </term>
-          <listitem>
-            <para>export RDTIMESTAMP environment variable to init, which is set to the uptime of the dracut start.</para>
-          </listitem>
-        </varlistentry>
       </variablelist>
     </refsect2>
     <refsect2>

modules.d/99base/init

@@ -332,12 +332,14 @@ for i in $(export -p); do
     i=${i#declare -x}
     i=${i#export}
     strstr "$i" "=" || continue
-    # skip RD_ vars
     i=${i%%=*}
     [ -z "$i" ] && continue
     case $i in
         root|PATH|HOME|TERM|PS4|RD_*)
             :;;
+        # skip RD_ vars and export them
+        RD_*)
+            export $i;;
         *)
             unset "$i";;
     esac
@@ -377,12 +379,6 @@ if getargbool 0 rd.copystate -y rdcopystate; then
     cp -axr /tmp/* /run/initramfs/ >/dev/null 2>&1
 fi
 
-if getargbool 1 rd.timestamp; then
-    export RD_TIMESTAMP
-else
-    unset RD_TIMESTAMP
-fi    
-
 info "Switching root"
 
 wait_for_loginit