On 13 Sep, Ian Dowse wrote: > For example, if you hold the reference count at 1 while calling the > cleanup function, it allows that function to safely add and drop > references, but if that cleanup function has a bug that drops one > too many references then you end up recursing instead of detecting > it as a negative reference count. I've found in some other code > that it works reasonably well to leave the reference count at zero, > but set a flag to stop further 1->0 transitions from retriggering > the cleanup. Obviously other approaches will work too.
The cleanup function shouldn't be mucking with the reference count, which means that the present implementation of nfs_inactive() is broken, but I think there is already general agreement on that point. The only possible exception would be to increase the reference count to pass a reference to another thread, but that would be a silly thing for a cleanup function to do, since it would no longer be cleaning up. We could add a flag that would cause an immediate panic if the cleanup function fiddled with the reference count as an aid to tracking down broken code ;-) To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message
