On Fri, May 28, 2021 at 03:58:42AM +0000, liweihang wrote: > Peter, could you please explain why you said "add_return and sub_return are > horrible interface for refcount"? What would you need them for? The only special value is 0. Once you hit 0 the object is dead and you cannot revive. If I look at drivers/infiniband/sw/rdmavt/mcast.c, which seems to be the relevant file, the thing that's called ->refcount is not in fact a reference count.
