cgroup/rstat: desc member cgrp in cgroup_rstat_flush_release

Recent change to cgroup_rstat_flush_release added a
parameter cgrp, which is used by tracepoint to correlate
with other tracepoints that also have this cgrp.

The kernel test robot detected kernel doc was missing
a description of this member.

Reported-by: kernel test robot <[email protected]>
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Signed-off-by: Jesper Dangaard Brouer <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>

Author: netoptimizer

kernel/cgroup/rstat.c

@@ -328,6 +328,7 @@ void cgroup_rstat_flush_hold(struct cgroup *cgrp)
 
 /**
  * cgroup_rstat_flush_release - release cgroup_rstat_flush_hold()
+ * @cgrp: cgroup used by tracepoint
  */
 void cgroup_rstat_flush_release(struct cgroup *cgrp)
 	__releases(&cgroup_rstat_lock)