Return-Path: linux-nfs-owner@vger.kernel.org Received: from fieldses.org ([174.143.236.118]:34771 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753816Ab3BUQae (ORCPT ); Thu, 21 Feb 2013 11:30:34 -0500 Date: Thu, 21 Feb 2013 11:30:30 -0500 From: "J. Bruce Fields" To: Chuck Lever Cc: Simo Sorce , "Myklebust, Trond" , "linux-nfs@vger.kernel.org" Subject: Re: synchronous AF_LOCAL connect Message-ID: <20130221163030.GC9743@fieldses.org> References: <2F275139-9861-4414-8C9F-BD74544C9AD7@oracle.com> <20130220160350.GJ14606@fieldses.org> <20130220163424.GK14606@fieldses.org> <4FA345DA4F4AE44899BD2B03EEEC2FA9235D7E49@SACEXCMBX04-PRD.hq.netapp.com> <1361381561.12328.441.camel@willson.li.ssimo.org> <20130220230337.GC3575@fieldses.org> <20130221162139.GB9743@fieldses.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-nfs-owner@vger.kernel.org List-ID: On Thu, Feb 21, 2013 at 11:27:29AM -0500, Chuck Lever wrote: > > On Feb 21, 2013, at 11:21 AM, J. Bruce Fields wrote: > > > On Wed, Feb 20, 2013 at 06:03:37PM -0500, J. Bruce Fields wrote: > >> OK, I've added that check and fixed some other bugs (thanks to Chuck for > >> some help in IRC). > >> > >> I think that gets rpcbind working in containers fine. > >> > >> gss-proxy has one more problem: it needs to do upcalls from nfsd threads > >> which won't have the right filesystem namespace. > >> > >> I get a write from gss-proxy when it starts and can do an initial > >> connect then using its context. But if we disconnect after that I'm > >> stuck. > >> > >> Does it cause any problems if I just set the idle_timeout to 0 for > >> AF_LOCAL? > > > > That gives me the following three patches. They work for me. > > > > Would it make more sense to make the idle timeout configurable? I > > couldn't see why disconnecting idle AF_LOCAL rpcbind connections would > > be particularly important anyway. > > I was expecting you to add a new flag to the rpc_clnt (like "disconnect on retry") that would disable the transport idle timeout. That would be OK with me too. What's best? --b. > > > > --b. > > > > commit 6656841afa0602f7aae3e42648eb44bfe79f7389 > > Author: J. Bruce Fields > > Date: Wed Feb 20 17:52:19 2013 -0500 > > > > SUNRPC: make AF_LOCAL connect synchronous > > > > It doesn't appear that anyone actually needs to connect asynchronously. > > > > Also, using a workqueue for the connect means we lose the namespace > > information from the original process. This is a problem since there's > > no way to explicitly pass in a filesystem namespace for resolution of an > > AF_LOCAL address. > > > > Signed-off-by: J. Bruce Fields > > > > diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c > > index bbc0915..b1df874 100644 > > --- a/net/sunrpc/xprtsock.c > > +++ b/net/sunrpc/xprtsock.c > > @@ -1866,13 +1866,9 @@ static int xs_local_finish_connecting(struct rpc_xprt *xprt, > > * @xprt: RPC transport to connect > > * @transport: socket transport to connect > > * @create_sock: function to create a socket of the correct type > > - * > > - * Invoked by a work queue tasklet. > > */ > > -static void xs_local_setup_socket(struct work_struct *work) > > +static void xs_local_setup_socket(struct sock_xprt *transport) > > { > > - struct sock_xprt *transport = > > - container_of(work, struct sock_xprt, connect_worker.work); > > struct rpc_xprt *xprt = &transport->xprt; > > struct socket *sock; > > int status = -EIO; > > @@ -1919,6 +1915,31 @@ out: > > current->flags &= ~PF_FSTRANS; > > } > > > > +static void xs_local_connect(struct rpc_task *task) > > +{ > > + struct rpc_xprt *xprt = task->tk_xprt; > > + struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); > > + unsigned long timeout; > > + > > + if (RPC_IS_ASYNC(task)) > > + rpc_exit(task, -ENOTCONN); > > + > > + if (transport->sock != NULL && !RPC_IS_SOFTCONN(task)) { > > + dprintk("RPC: xs_connect delayed xprt %p for %lu " > > + "seconds\n", > > + xprt, xprt->reestablish_timeout / HZ); > > + timeout = xprt->reestablish_timeout; > > + xprt->reestablish_timeout <<= 1; > > + if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO) > > + xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO; > > + if (xprt->reestablish_timeout > XS_TCP_MAX_REEST_TO) > > + xprt->reestablish_timeout = XS_TCP_MAX_REEST_TO; > > + rpc_delay(task, timeout); > > + } else > > + dprintk("RPC: xs_connect scheduled xprt %p\n", xprt); > > + xs_local_setup_socket(transport); > > +} > > + > > #ifdef CONFIG_SUNRPC_SWAP > > static void xs_set_memalloc(struct rpc_xprt *xprt) > > { > > @@ -2454,7 +2475,7 @@ static struct rpc_xprt_ops xs_local_ops = { > > .alloc_slot = xprt_alloc_slot, > > .rpcbind = xs_local_rpcbind, > > .set_port = xs_local_set_port, > > - .connect = xs_connect, > > + .connect = xs_local_connect, > > .buf_alloc = rpc_malloc, > > .buf_free = rpc_free, > > .send_request = xs_local_send_request, > > @@ -2627,8 +2648,6 @@ static struct rpc_xprt *xs_setup_local(struct xprt_create *args) > > goto out_err; > > } > > xprt_set_bound(xprt); > > - INIT_DELAYED_WORK(&transport->connect_worker, > > - xs_local_setup_socket); > > xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL); > > break; > > default: > > > > commit 3d622fe729b9b4382785c3ef2ef61e484df1b3ec > > Author: J. Bruce Fields > > Date: Thu Feb 21 10:14:22 2013 -0500 > > > > SUNRPC: attempt AF_LOCAL connect on setup > > > > In the gss-proxy case, setup time is when I know I'll have the right > > namespace for the connect. > > > > In other cases, it might be useful to get any connection errors > > earlier--though actually in practice it doesn't make any difference for > > rpcbind. > > > > Signed-off-by: J. Bruce Fields > > > > diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c > > index b1df874..f2cf652 100644 > > --- a/net/sunrpc/xprtsock.c > > +++ b/net/sunrpc/xprtsock.c > > @@ -1867,7 +1867,7 @@ static int xs_local_finish_connecting(struct rpc_xprt *xprt, > > * @transport: socket transport to connect > > * @create_sock: function to create a socket of the correct type > > */ > > -static void xs_local_setup_socket(struct sock_xprt *transport) > > +static int xs_local_setup_socket(struct sock_xprt *transport) > > { > > struct rpc_xprt *xprt = &transport->xprt; > > struct socket *sock; > > @@ -1913,6 +1913,7 @@ out: > > xprt_clear_connecting(xprt); > > xprt_wake_pending_tasks(xprt, status); > > current->flags &= ~PF_FSTRANS; > > + return status; > > } > > > > static void xs_local_connect(struct rpc_task *task) > > @@ -2649,6 +2650,9 @@ static struct rpc_xprt *xs_setup_local(struct xprt_create *args) > > } > > xprt_set_bound(xprt); > > xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL); > > + ret = ERR_PTR(xs_local_setup_socket(transport)); > > + if (ret) > > + goto out_err; > > break; > > default: > > ret = ERR_PTR(-EAFNOSUPPORT); > > > > commit 1a67db92015506ca07e6fc7a24583917adcbb43d > > Author: J. Bruce Fields > > Date: Wed Feb 20 18:08:52 2013 -0500 > > > > SUNRPC: no idle timeout for AF_LOCAL sockets > > > > In the gss-proxy case I don't want to have to reconnect at random--I > > want to connect only on gss-proxy startup when I can steal gss-proxy's > > context to do the connect in the right namespace. > > > > And surely an AF_LOCAL socket isn't a ton of state to keep around--how > > about we just turn off the idle timeout for AF_LOCAL sockets. > > > > Signed-off-by: J. Bruce Fields > > > > diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c > > index f2cf652..a32227e 100644 > > --- a/net/sunrpc/xprtsock.c > > +++ b/net/sunrpc/xprtsock.c > > @@ -2635,7 +2635,7 @@ static struct rpc_xprt *xs_setup_local(struct xprt_create *args) > > > > xprt->bind_timeout = XS_BIND_TO; > > xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO; > > - xprt->idle_timeout = XS_IDLE_DISC_TO; > > + xprt->idle_timeout = 0; > > > > xprt->ops = &xs_local_ops; > > xprt->timeout = &xs_local_default_timeout; > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > -- > Chuck Lever > chuck[dot]lever[at]oracle[dot]com > > > >