From mboxrd@z Thu Jan 1 00:00:00 1970 From: Trond Myklebust Subject: Re: [PATCH v2 3/5] SUNRPC: make RPC service dependable on rpcbind clients creation Date: Fri, 09 Sep 2011 14:44:34 -0400 Message-ID: <1315593874.17611.19.camel@lade.trondhjem.org> References: <20110909115146.13697.71682.stgit@localhost6.localdomain6> <20110909120844.13697.48102.stgit@localhost6.localdomain6> <20110909100745.7e2e8bf9@corrin.poochiereds.net> <4E6A41D4.6090001@parallels.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Jeff Layton , "linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Pavel Emelianov , "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" To: Stanislav Kinsbursky Return-path: In-Reply-To: <4E6A41D4.6090001-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org> Sender: linux-nfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org On Fri, 2011-09-09 at 20:41 +0400, Stanislav Kinsbursky wrote:=20 > 09.09.2011 18:07, Jeff Layton =D0=BF=D0=B8=D1=88=D0=B5=D1=82: > > On Fri, 09 Sep 2011 16:08:44 +0400 > > Stanislav Kinsbursky wrote: > > > >> Create rcbind clients or increase rpcbind users counter during RPC= service > >> creation and decrease this counter (and possibly destroy those cli= ents) on RPC > >> service destruction. > >> > >> Signed-off-by: Stanislav Kinsbursky > >> > >> --- > >> include/linux/sunrpc/clnt.h | 2 ++ > >> net/sunrpc/rpcb_clnt.c | 2 +- > >> net/sunrpc/svc.c | 13 +++++++++++-- > >> 3 files changed, 14 insertions(+), 3 deletions(-) > >> > >> diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/cl= nt.h > >> index db7bcaf..65a8115 100644 > >> --- a/include/linux/sunrpc/clnt.h > >> +++ b/include/linux/sunrpc/clnt.h > >> @@ -135,10 +135,12 @@ void rpc_shutdown_client(struct rpc_clnt *)= ; > >> void rpc_release_client(struct rpc_clnt *); > >> void rpc_task_release_client(struct rpc_task *); > >> > >> +int rpcb_create_local(void); > >> int rpcb_register(u32, u32, int, unsigned short); > >> int rpcb_v4_register(const u32 program, const u32 version, > >> const struct sockaddr *address, > >> const char *netid); > >> +void rpcb_put_local(void); > >> void rpcb_getport_async(struct rpc_task *); > >> > >> void rpc_call_start(struct rpc_task *); > >> diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c > >> index b4cc0f1..437ec60 100644 > >> --- a/net/sunrpc/rpcb_clnt.c > >> +++ b/net/sunrpc/rpcb_clnt.c > >> @@ -318,7 +318,7 @@ out: > >> * Returns zero on success, otherwise a negative errno value > >> * is returned. > >> */ > >> -static int rpcb_create_local(void) > >> +int rpcb_create_local(void) > >> { > >> static DEFINE_MUTEX(rpcb_create_local_mutex); > >> int result =3D 0; > >> diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c > >> index 6a69a11..9095c0e 100644 > >> --- a/net/sunrpc/svc.c > >> +++ b/net/sunrpc/svc.c > >> @@ -367,8 +367,11 @@ __svc_create(struct svc_program *prog, unsign= ed int bufsize, int npools, > >> unsigned int xdrsize; > >> unsigned int i; > >> > >> - if (!(serv =3D kzalloc(sizeof(*serv), GFP_KERNEL))) > >> + if (rpcb_create_local()< 0) > >> return NULL; > >> + > >> + if (!(serv =3D kzalloc(sizeof(*serv), GFP_KERNEL))) > >> + goto out_err; > >> serv->sv_name =3D prog->pg_name; > >> serv->sv_program =3D prog; > >> serv->sv_nrthreads =3D 1; > >> @@ -403,7 +406,7 @@ __svc_create(struct svc_program *prog, unsigne= d int bufsize, int npools, > >> GFP_KERNEL); > >> if (!serv->sv_pools) { > >> kfree(serv); > >> - return NULL; > >> + goto out_err; > >> } > >> > >> for (i =3D 0; i< serv->sv_nrpools; i++) { > >> @@ -423,6 +426,10 @@ __svc_create(struct svc_program *prog, unsign= ed int bufsize, int npools, > >> svc_unregister(serv); > >> > >> return serv; > >> + > >> +out_err: > >> + rpcb_put_local(); > >> + return NULL; > >> } > >> > >> struct svc_serv * > >> @@ -491,6 +498,8 @@ svc_destroy(struct svc_serv *serv) > >> svc_unregister(serv); > >> kfree(serv->sv_pools); > >> kfree(serv); > >> + > >> + rpcb_put_local(); > >> } > >> EXPORT_SYMBOL_GPL(svc_destroy); > >> > >> > > > > I don't get it -- what's the advantage of creating rpcbind clients = in > > __svc_create vs. the old way of creating them just before we plan t= o > > use them? > > >=20 > The main problem here is not in creation, but in destroying those cli= ents. > Now rpcbind clients are created during rpcb_register(). I.e. once per= every family, program version and so on. > But can be unregistered for all protocol families by one call. So it'= s impossible to put reference counting for those clients in the place, = where they are created now. Could we perhaps set up a 'struct pernet_operations' to create a destructor for them? Cheers Trond --=20 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