From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stanislav Kinsbursky Subject: [PATCH v2 1/4] SUNRPC: release per-net clients lock before calling PipeFS dentries creation Date: Mon, 27 Feb 2012 19:50:55 +0400 Message-ID: <20120227155055.7941.18741.stgit@localhost6.localdomain6> References: <20120227154713.7941.17963.stgit@localhost6.localdomain6> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: linux-nfs@vger.kernel.org, xemul@parallels.com, neilb@suse.de, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, jbottomley@parallels.com, bfields@fieldses.org, davem@davemloft.net, devel@openvz.org To: Trond.Myklebust@netapp.com Return-path: In-Reply-To: <20120227154713.7941.17963.stgit@localhost6.localdomain6> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Lockdep is sad otherwise, because inode mutex is taken on PipeFS dentry creation, which can be called on mount notification, where this per-net client lock is taken on clients list walk. Signed-off-by: Stanislav Kinsbursky --- net/sunrpc/clnt.c | 10 +++++++--- 1 files changed, 7 insertions(+), 3 deletions(-) diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index bb7ed2f3..ddb5741 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -84,7 +84,7 @@ static void rpc_register_client(struct rpc_clnt *clnt) struct sunrpc_net *sn = net_generic(clnt->cl_xprt->xprt_net, sunrpc_net_id); spin_lock(&sn->rpc_client_lock); - list_add(&clnt->cl_clients, &sn->all_clients); + list_add_tail(&clnt->cl_clients, &sn->all_clients); spin_unlock(&sn->rpc_client_lock); } @@ -208,15 +208,19 @@ static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event, void *ptr) { struct super_block *sb = ptr; - struct rpc_clnt *clnt; + struct rpc_clnt *clnt, *tmp; int error = 0; struct sunrpc_net *sn = net_generic(sb->s_fs_info, sunrpc_net_id); spin_lock(&sn->rpc_client_lock); - list_for_each_entry(clnt, &sn->all_clients, cl_clients) { + list_for_each_entry_safe(clnt, tmp, &sn->all_clients, cl_clients) { + atomic_inc(&clnt->cl_count); + spin_unlock(&sn->rpc_client_lock); error = __rpc_pipefs_event(clnt, event, sb); + rpc_release_client(clnt); if (error) break; + spin_lock(&sn->rpc_client_lock); } spin_unlock(&sn->rpc_client_lock); return error;