On Wed, Apr 24, 2019 at 01:37:04PM +0200, Oleg Nesterov wrote:
> On 04/23, Paul E. McKenney wrote:
> >
> > I wordsmithed the commit log and merged in the RCU-bh and RCU checks
> > to rcu_sync_is_idle(), with the result shown below. Does that work
> > OK, or did I mess something up?
>
> Yes, thanks!
>
> the additional RCU-bh and RCU checks matches the "or introduce
> rcu_read_lock_any_held()"
> note from the changelog, perhaps it makes some sense...
>
> Just one nit below,
>
> > - * Must be invoked within an RCU read-side critical section whose
> > - * flavor matches that of the rcu_sync struture.
> > + * Must be invoked within an RCU-sched read-side critical section.
> ^^^^^^^^^
>
> Given that the actual code:
>
> > static inline bool rcu_sync_is_idle(struct rcu_sync *rsp)
> > {
> > -#ifdef CONFIG_PROVE_RCU
> > - rcu_sync_lockdep_assert(rsp);
> > -#endif
> > + RCU_LOCKDEP_WARN(!rcu_read_lock_held() &&
> > + !rcu_read_lock_bh_held() &&
> > + !rcu_read_lock_sched_held(),
> > + "suspicious rcu_sync_is_idle() usage");
>
> does RCU_LOCKDEP_WARN(!rcu_read_lock_any()) the comment should say
>
> Must be invoked within an RCU read-side critical section of
> any flavor
Good catch, thank you! I went with this:
* Must be invoked within some flavor of RCU read-side critical section.
Does that work for you?
Thanx, Paul
