Re: Is there a reason we don't have kvfree_rcu()?

["Paul E. McKenney" <paulmck@kernel.org>]

On Thu, Mar 12, 2020 at 04:27:30PM +0000, George Spelvin wrote:
> kvfree() is a superset of kfree(), so there's nothing obvious stopping 
> kfree_rcu() from simply changing to kvfree() and everything will keep 
> working.
> 
> I'd probably add a kvfree_rcu() alias, just for documentation's sake and
> to make code that depends on the new feature explode at compile time, but
> it could be identical behind the scenes.
> 
> There's an existing user in mm/list_lru.c already.
> 
> I was just thinking of using kvmalloc() in a module, and realized that the 
> lack of a core kvfree_rcu() helper meant I'd have to synchronize_rcu() on 
> module unload.

There was a recent proposal to do just that, but current patches in -rcu
use kfree_bulk().  It doesn't look to me that this works for kfvree()
under the covers in its current form.  Could it be upgraded to handle
this case?

Adding Vlad on CC for his thoughts.

							Thanx, Paul