From mboxrd@z Thu Jan 1 00:00:00 1970 From: Trond Myklebust Subject: Re: [PATCH v6 1/8] SUNRPC: introduce helpers for reference counted rpcbind clients Date: Tue, 25 Oct 2011 13:16:09 +0200 Message-ID: <1319541369.2716.1.camel@lade.trondhjem.org> References: <20111025100826.12689.46944.stgit@localhost6.localdomain6> <20111025101608.12689.68689.stgit@localhost6.localdomain6> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Cc: linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, xemul-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org, neilb-l3A5Bk7waGM@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, bfields-uC3wQj2KruNg9hUCZPvPmw@public.gmane.org, davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org, devel-GEFAQzZX7r8dnm+yROfE0A@public.gmane.org To: Stanislav Kinsbursky Return-path: In-Reply-To: <20111025101608.12689.68689.stgit-bi+AKbBUZKagILUCTcTcHdKyNwTtLsGr@public.gmane.org> Sender: linux-nfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org On Tue, 2011-10-25 at 14:16 +0300, Stanislav Kinsbursky wrote: > v6: > 1) added write memory barrier to rpcb_set_local to make sure, that rpcbind > clients become valid before rpcb_users assignment > 2) explicitly set rpcb_users to 1 instead of incrementing it (looks clearer from > my pow). > > v5: fixed races with rpcb_users in rpcb_get_local() > > This helpers will be used for dynamical creation and destruction of rpcbind > clients. > Variable rpcb_users is actually a counter of lauched RPC services. If rpcbind > clients has been created already, then we just increase rpcb_users. > > Signed-off-by: Stanislav Kinsbursky > > --- > net/sunrpc/rpcb_clnt.c | 54 ++++++++++++++++++++++++++++++++++++++++++++++++ > 1 files changed, 54 insertions(+), 0 deletions(-) > > diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c > index e45d2fb..9fcdb42 100644 > --- a/net/sunrpc/rpcb_clnt.c > +++ b/net/sunrpc/rpcb_clnt.c > @@ -114,6 +114,9 @@ static struct rpc_program rpcb_program; > static struct rpc_clnt * rpcb_local_clnt; > static struct rpc_clnt * rpcb_local_clnt4; > > +DEFINE_SPINLOCK(rpcb_clnt_lock); > +unsigned int rpcb_users; > + > struct rpcbind_args { > struct rpc_xprt * r_xprt; > > @@ -161,6 +164,57 @@ static void rpcb_map_release(void *data) > kfree(map); > } > > +static int rpcb_get_local(void) > +{ > + int cnt; > + > + spin_lock(&rpcb_clnt_lock); > + if (rpcb_users) > + rpcb_users++; > + cnt = rpcb_users; > + spin_unlock(&rpcb_clnt_lock); > + > + return cnt; > +} > + > +void rpcb_put_local(void) > +{ > + struct rpc_clnt *clnt = rpcb_local_clnt; > + struct rpc_clnt *clnt4 = rpcb_local_clnt4; > + int shutdown; > + > + spin_lock(&rpcb_clnt_lock); > + if (--rpcb_users == 0) { > + rpcb_local_clnt = NULL; > + rpcb_local_clnt4 = NULL; > + } > + shutdown = !rpcb_users; > + spin_unlock(&rpcb_clnt_lock); > + > + if (shutdown) { > + /* > + * cleanup_rpcb_clnt - remove xprtsock's sysctls, unregister > + */ > + if (clnt4) > + rpc_shutdown_client(clnt4); > + if (clnt) > + rpc_shutdown_client(clnt); > + } > + return; I'm removing this before applying... > +} > + -- Trond Myklebust Linux NFS client maintainer NetApp Trond.Myklebust-HgOvQuBEEgTQT0dZR+AlfA@public.gmane.org www.netapp.com -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html