On Tue, 1 Dec 2020 16:28:47 -0500 Steven Rostedt <rostedt@xxxxxxxxxxx> wrote: > On Tue, 1 Dec 2020 12:32:49 -0800 > Axel Rasmussen <axelrasmussen@xxxxxxxxxx> wrote: > > > +/* Called with reg_lock held. */ > > The above comment is reduntant, as the lockdep_is_held() below also suggest > that it is ;-) > > > > static inline char *get_memcg_path_buf(void) > > { > > + char *buf; > > int idx; > > > > + rcu_read_lock(); > > The caller of get_mm_memcg_path() has preemption disabled, which is also > now an RCU lock. So the rcu_read_lock() is somewhat redundant. BTW, both of these comments are FYI. You can keep the comment and keep the rcu_read_lock(). I was just stating that they are redundant, but keeping them may make the code a bit more robust. -- Steve