From: Trond Myklebust Subject: [PATCH 1/7] SUNRPC: Fix a race in xs_tcp_state_change() Date: Tue, 06 Nov 2007 19:39:40 -0500 Message-ID: <20071107003940.13713.65472.stgit@heimdal.trondhjem.org> References: <20071107003834.13713.73536.stgit@heimdal.trondhjem.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Cc: nfsv4@linux-nfs.org, nfs@lists.sourceforge.net To: Chuck Lever , Tom Talpey Return-path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.91] helo=mail.sourceforge.net) by sc8-sf-list2-new.sourceforge.net with esmtp (Exim 4.43) id 1IpYw8-0002SS-VC for nfs@lists.sourceforge.net; Tue, 06 Nov 2007 16:38:29 -0800 Received: from c-69-242-210-120.hsd1.mi.comcast.net ([69.242.210.120] helo=heimdal.trondhjem.org) by mail.sourceforge.net with esmtp (Exim 4.44) id 1IpYwE-000512-Ew for nfs@lists.sourceforge.net; Tue, 06 Nov 2007 16:38:34 -0800 In-Reply-To: <20071107003834.13713.73536.stgit@heimdal.trondhjem.org> List-Id: "Discussion of NFS under Linux development, interoperability, and testing." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: nfs-bounces@lists.sourceforge.net Errors-To: nfs-bounces@lists.sourceforge.net From: Trond Myklebust When scheduling the autoclose RPC call, we want to ensure that we don't race against the test_bit() call in xprt_clear_locked(). Signed-off-by: Trond Myklebust --- include/linux/sunrpc/xprt.h | 1 + net/sunrpc/xprt.c | 20 ++++++++++++++++++++ net/sunrpc/xprtsock.c | 5 +---- 3 files changed, 22 insertions(+), 4 deletions(-) diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h index 30b17b3..6f524a9 100644 --- a/include/linux/sunrpc/xprt.h +++ b/include/linux/sunrpc/xprt.h @@ -246,6 +246,7 @@ struct rpc_rqst * xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid); void xprt_complete_rqst(struct rpc_task *task, int copied); void xprt_release_rqst_cong(struct rpc_task *task); void xprt_disconnect(struct rpc_xprt *xprt); +void xprt_force_disconnect(struct rpc_xprt *xprt); /* * Reserved bit positions in xprt->state diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c index 282a9a2..48c5a8b 100644 --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -570,6 +570,7 @@ static void xprt_autoclose(struct work_struct *work) xprt_disconnect(xprt); xprt->ops->close(xprt); + clear_bit(XPRT_CLOSE_WAIT, &xprt->state); xprt_release_write(xprt, NULL); } @@ -588,6 +589,25 @@ void xprt_disconnect(struct rpc_xprt *xprt) } EXPORT_SYMBOL_GPL(xprt_disconnect); +/** + * xprt_force_disconnect - force a transport to disconnect + * @xprt: transport to disconnect + * + */ +void xprt_force_disconnect(struct rpc_xprt *xprt) +{ + /* Don't race with the test_bit() in xprt_clear_locked() */ + spin_lock_bh(&xprt->transport_lock); + set_bit(XPRT_CLOSE_WAIT, &xprt->state); + /* Try to schedule an autoclose RPC call */ + if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) + queue_work(rpciod_workqueue, &xprt->task_cleanup); + else if (xprt->snd_task != NULL) + rpc_wake_up_task(xprt->snd_task); + spin_unlock_bh(&xprt->transport_lock); +} +EXPORT_SYMBOL_GPL(xprt_force_disconnect); + static void xprt_init_autodisconnect(unsigned long data) { diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 02298f5..322e4e2 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -1118,10 +1118,7 @@ static void xs_tcp_state_change(struct sock *sk) case TCP_SYN_RECV: break; case TCP_CLOSE_WAIT: - /* Try to schedule an autoclose RPC calls */ - set_bit(XPRT_CLOSE_WAIT, &xprt->state); - if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) - queue_work(rpciod_workqueue, &xprt->task_cleanup); + xprt_force_disconnect(xprt); default: xprt_disconnect(xprt); } ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs