Re: [PATCH 02/36] scsi,rcu: convert call_rcu(fc_rport_free_rcu) to kfree_rcu()

On Tue, 2011-03-22 at 23:50 -0700, Paul E. McKenney wrote:

The kfree_rcu() definition is as
follows:

#define kfree_rcu(ptr, rcu_head)					\
	__kfree_rcu(&((ptr)->rcu_head), offsetof(typeof(*(ptr)), rcu_head))

Isn't this one of those cases where the obvious use of the interface is
definitely wrong?

It's also another nasty pseudo C prototype.  I know we do this sort of
thing for container_of et al, but I don't really think we want to extend
it.

Why not make the interface take a pointer to the embedding structure and
one to the rcu_head ... that way all pointer mathematics can be
contained inside the RCU routines.

James