Re: [PATCH] rcu/sync: kill rcu_sync_type/gp_type

[Oleg Nesterov <oleg@redhat.com>]

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

?

Oleg.