From patchwork Thu Nov 22 04:48:22 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [3.5.yuz, extended, stable] Patch "SUNRPC: Get rid of the xs_error_report socket callback" has been added to staging queue Date: Wed, 21 Nov 2012 18:48:22 -0000 From: Herton Ronaldo Krzesinski X-Patchwork-Id: 200979 Message-Id: <1353559702-2074-1-git-send-email-herton.krzesinski@canonical.com> To: Trond Myklebust Cc: Chris Perl , kernel-team@lists.ubuntu.com This is a note to let you know that I have just added a patch titled SUNRPC: Get rid of the xs_error_report socket callback to the linux-3.5.y-queue branch of the 3.5.yuz extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.yuz tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Herton ------ >From 76d1975c9f45a3d6155427c90719f21d0dffd3db Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 22 Oct 2012 17:14:36 -0400 Subject: [PATCH] SUNRPC: Get rid of the xs_error_report socket callback commit f878b657ce8e7d3673afe48110ec208a29e38c4a upstream. Chris Perl reports that we're seeing races between the wakeup call in xs_error_report and the connect attempts. Basically, Chris has shown that in certain circumstances, the call to xs_error_report causes the rpc_task that is responsible for reconnecting to wake up early, thus triggering a disconnect and retry. Since the sk->sk_error_report() calls in the socket layer are always followed by a tcp_done() in the cases where we care about waking up the rpc_tasks, just let the state_change callbacks take responsibility for those wake ups. Reported-by: Chris Perl Signed-off-by: Trond Myklebust Tested-by: Chris Perl Signed-off-by: Herton Ronaldo Krzesinski --- net/sunrpc/xprtsock.c | 25 ------------------------- 1 file changed, 25 deletions(-) -- 1.7.9.5 diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 67c46ec..420abf8 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -254,7 +254,6 @@ struct sock_xprt { void (*old_data_ready)(struct sock *, int); void (*old_state_change)(struct sock *); void (*old_write_space)(struct sock *); - void (*old_error_report)(struct sock *); }; /* @@ -781,7 +780,6 @@ static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk) transport->old_data_ready = sk->sk_data_ready; transport->old_state_change = sk->sk_state_change; transport->old_write_space = sk->sk_write_space; - transport->old_error_report = sk->sk_error_report; } static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk) @@ -789,7 +787,6 @@ static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *s sk->sk_data_ready = transport->old_data_ready; sk->sk_state_change = transport->old_state_change; sk->sk_write_space = transport->old_write_space; - sk->sk_error_report = transport->old_error_report; } static void xs_reset_transport(struct sock_xprt *transport) @@ -1558,25 +1555,6 @@ static void xs_tcp_state_change(struct sock *sk) read_unlock_bh(&sk->sk_callback_lock); } -/** - * xs_error_report - callback mainly for catching socket errors - * @sk: socket - */ -static void xs_error_report(struct sock *sk) -{ - struct rpc_xprt *xprt; - - read_lock_bh(&sk->sk_callback_lock); - if (!(xprt = xprt_from_sock(sk))) - goto out; - dprintk("RPC: %s client %p...\n" - "RPC: error %d\n", - __func__, xprt, sk->sk_err); - xprt_wake_pending_tasks(xprt, -EAGAIN); -out: - read_unlock_bh(&sk->sk_callback_lock); -} - static void xs_write_space(struct sock *sk) { struct socket *sock; @@ -1876,7 +1854,6 @@ static int xs_local_finish_connecting(struct rpc_xprt *xprt, sk->sk_user_data = xprt; sk->sk_data_ready = xs_local_data_ready; sk->sk_write_space = xs_udp_write_space; - sk->sk_error_report = xs_error_report; sk->sk_allocation = GFP_ATOMIC; xprt_clear_connected(xprt); @@ -1965,7 +1942,6 @@ static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock) sk->sk_user_data = xprt; sk->sk_data_ready = xs_udp_data_ready; sk->sk_write_space = xs_udp_write_space; - sk->sk_error_report = xs_error_report; sk->sk_no_check = UDP_CSUM_NORCV; sk->sk_allocation = GFP_ATOMIC; @@ -2079,7 +2055,6 @@ static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock) sk->sk_data_ready = xs_tcp_data_ready; sk->sk_state_change = xs_tcp_state_change; sk->sk_write_space = xs_tcp_write_space; - sk->sk_error_report = xs_error_report; sk->sk_allocation = GFP_ATOMIC; /* socket options */