On Thu, May 13, 2010 at 05:36:15PM +0300, Benny Halevy wrote: > On May. 13, 2010, 1:29 +0300, "J. Bruce Fields" <bfields@xxxxxxxxxxxxxx> wrote: > > Another case: > > > > - Two 4.1 compounds arrive, both their sequence operations are > > processed. > > - Independently, an exchange_id expires the client. > > - At this point, the reference count is 2. > > - One of the original compounds completes. It renews the client > > (because it hits reference count 1). > > and that will be a no-op as the client is marked as expired. Pfft, apologies, and thanks for setting me straight again. Still, the existing scheme seems slightly more complicated than necessary. > > > - The second of the two original compounds completes. It frees > > the client. > > right > > > > > I guess there's nothing fundamentally wrong with that, but it's a little > > odd. > > > > Wouldn't it be more straightforward to let cl_refcount be a count of the > > number of outstanding compounds, and make release_session_client do: > > > > if cl_refcount >= 0 > > return; > > if (client_is_expired(clp)) > > free client; > > else > > renew client; > > > > ? > > > > The following works for me. If you don't see any objection, I'll squash > > this in and push out the result. > > No objection, looks good. Thanks! OK, thanks! I notice I didn't do exactly what I said I would, though; with the following change on top I think it's right. I'll test that and then push out the result. --b. diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 05ad0ae..84b0fe9 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -765,7 +765,7 @@ expire_client(struct nfs4_client *clp) list_del(&clp->cl_strhash); spin_lock(&client_lock); unhash_client_locked(clp); - if (atomic_dec_and_test(&clp->cl_refcount)) + if (atomic_read(&clp->cl_refcount) == 0) free_client(clp); spin_unlock(&client_lock); } @@ -853,7 +853,7 @@ static struct nfs4_client *create_client(struct xdr_netobj name, char *recdir, } memcpy(clp->cl_recdir, recdir, HEXDIR_LEN); - atomic_set(&clp->cl_refcount, 1); + atomic_set(&clp->cl_refcount, 0); atomic_set(&clp->cl_cb_set, 0); INIT_LIST_HEAD(&clp->cl_idhash); INIT_LIST_HEAD(&clp->cl_strhash); -- 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
