Return-Path: linux-nfs-owner@vger.kernel.org Received: from fieldses.org ([174.143.236.118]:36081 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753836Ab3BUQVo (ORCPT ); Thu, 21 Feb 2013 11:21:44 -0500 Date: Thu, 21 Feb 2013 11:21:39 -0500 From: "J. Bruce Fields" To: Simo Sorce Cc: "Myklebust, Trond" , Chuck Lever , "linux-nfs@vger.kernel.org" Subject: Re: synchronous AF_LOCAL connect Message-ID: <20130221162139.GB9743@fieldses.org> References: <20130218225424.GD3391@fieldses.org> <20130220154751.GH14606@fieldses.org> <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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20130220230337.GC3575@fieldses.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: 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. --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;