Re: [PATCH v3 for-next 13/13] RDMA/rdmavt: Use refcount_t instead of atomic_t on refcount of rvt_mcast
From: Peter Zijlstra <peterz@infradead.org>
Date: 2021-05-28 07:01:40
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.