Messages in this thread | | | Date | Thu, 19 Jun 2014 14:07:33 -0700 | From | "Paul E. McKenney" <> | Subject | Re: [PATCH 6/6] percpu-refcount: implement percpu_ref_reinit() and percpu_ref_is_zero() |
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On Thu, Jun 19, 2014 at 03:06:00PM -0400, Tejun Heo wrote: > Hello, > > On Thu, Jun 19, 2014 at 10:05:49AM -0700, Paul E. McKenney wrote: > > If you mean what I think you mean by load_acquire_depends(), it is spelled > > "rcu_dereference()" or, in this case, where you are never removing anything > > that has been added, "rcu_dereference_raw()". Because you are never > > removing anything, you don't need rcu_read_lock() or rcu_read_unlock(), > > thus you don't want lockdep yelling at you about not having RCU read-side > > critical sections, thus rcu_dereference_raw(). > > Yeah, along that line but it's kinda weird to use rcu_dereference() > when RCU isn't involved. It'd be clearer to have something like > load_acquire_depends() and then define RCU deref in terms of it. > > This is purely notational and clarifiying in the documentation is > probably enough.
OK. If there end up being too many non-RCU uses of rcu_dereference_raw(), then it might make sense to create a new primitive. But it is not like we have any shortage of them just now. ;-)
Thanx, Paul
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