Re: [patch] Add kref_read and kref_put_last primitives

[Greg KH <greg@kroah.com>]

On Mon, Jul 26, 2004 at 05:31:51PM +0100, Christoph Hellwig wrote:
> On Mon, Jul 26, 2004 at 08:18:56PM +0530, Ravikiran G Thirumalai wrote:
> > Greg,
> > Here is a patch to add kref_read and kref_put_last.
> > These primitives were needed to change files_struct.f_count
> > refcounter to use kref api.
> > 
> > kref_put_last is needed sometimes when a refcount might
> > have an unconventional release which needs more than
> > the refcounted object to process object release-- like in the
> > files_struct.f_count conversion patch at __aio_put_req().
> > The following patch depends on kref shrinkage patches.
> > (which you have already included).
> 
> Why don't you simply use an atomic_t if that's what you seem to
> want?

Exactly.  In cases like this, where the user, for some reason, wants to
know the state of the reference count, they should not use a struct
kref.  I'm not going to add these functions to the kref api, sorry.

thanks,

greg k-h