On Tue, Mar 01, 2005 at 10:02:43PM +0100, Arjan van de Ven wrote: > On Tue, 2005-03-01 at 12:15 -0800, Greg KH wrote: > > On Sat, Feb 26, 2005 at 04:23:04PM -0600, Corey Minyard wrote: > > > Add a routine to kref that allows the kref_put() routine to be > > > unserialized even when the get routine attempts to kref_get() > > > an object without first holding a valid reference to it. This is > > > useful in situations where this happens multiple times without > > > freeing the object, as it will avoid having to do a lock/semaphore > > > except on the final kref_put(). > > > > > > This also adds some kref documentation to the Documentation > > > directory. > > > > I like the first part of the documentation, that's nice. > > > > But I don't like the new kref_get_with_check() function that you > > implemented. If you look in the -mm tree, kref_put() now returns if > > this was the last put on the reference count or not, to help with lists > > of objects with a kref in it. > > > > Perhaps you can use that to implement what you need instead? > > note that I'm not convinced the "lockless" implementation actually is > faster. It still uses an atomic variable, which is just as expensive as > taking a lock normally...
I have never stated it would be "faster" that I know of, and you still need a lock to protect some of the paths. But that is documented in my 2004 ols paper about kref. thanks, greg k-h - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
