On Mon, Feb 13, 2017 at 5:38 AM, Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > On Sat, Feb 11, 2017 at 09:01:15AM -0500, David Windsor wrote: >> I'm not sure there's another way to accomplish what we need >> (initializing struct nfsd4_session objects with refcount=1) without >> also modifying the freeable reference state. After migrating to the >> refcount_t API, if we leave init_session() as is, the first call to >> nfsd4_get_session_locked() will fail: > > Which is a pretty clear indicator that this code should simply not > migrate to the recount_t API. Why was it even considered if the > conversion is obviously broken? I'm not sure this is a sound argument for not converting to refcount_t. In other locations in which refcounting schemes are "unnatural," i.e. freeing refcounted objects when their refcount is -1 (rather than 0), conversion to refcount_t is accomplished by performing a logical +1 to the overall refcounting scheme. We're auditing all refcounting corner cases, such as these, to see if similar solutions can be found. Thanks, David -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
