[PATCH 3.16.y-ckt 071/254] SUNRPC: Don't wake tasks during connection abort

From: Luis Henriques
Date: Tue Nov 25 2014 - 05:41:19 EST


3.16.7-ckt2 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Benjamin Coddington <bcodding@xxxxxxxxxx>

commit a743419f420a64d442280845c0377a915b76644f upstream.

When aborting a connection to preserve source ports, don't wake the task in
xs_error_report. This allows tasks with RPC_TASK_SOFTCONN to succeed if the
connection needs to be re-established since it preserves the task's status
instead of setting it to the status of the aborting kernel_connect().

This may also avoid a potential conflict on the socket's lock.

Signed-off-by: Benjamin Coddington <bcodding@xxxxxxxxxx>
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
---
include/linux/sunrpc/xprt.h | 1 +
net/sunrpc/xprtsock.c | 4 ++++
2 files changed, 5 insertions(+)

diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
index fcbfe8783243..cf391eef2e6d 100644
--- a/include/linux/sunrpc/xprt.h
+++ b/include/linux/sunrpc/xprt.h
@@ -357,6 +357,7 @@ int xs_swapper(struct rpc_xprt *xprt, int enable);
#define XPRT_CONNECTION_ABORT (7)
#define XPRT_CONNECTION_CLOSE (8)
#define XPRT_CONGESTED (9)
+#define XPRT_CONNECTION_REUSE (10)

static inline void xprt_set_connected(struct rpc_xprt *xprt)
{
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index be8bbd5d65ec..ab52cefa8f39 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -842,6 +842,8 @@ static void xs_error_report(struct sock *sk)
dprintk("RPC: xs_error_report client %p, error=%d...\n",
xprt, -err);
trace_rpc_socket_error(xprt, sk->sk_socket, err);
+ if (test_bit(XPRT_CONNECTION_REUSE, &xprt->state))
+ goto out;
xprt_wake_pending_tasks(xprt, err);
out:
read_unlock_bh(&sk->sk_callback_lock);
@@ -2241,7 +2243,9 @@ static void xs_tcp_setup_socket(struct work_struct *work)
abort_and_exit = test_and_clear_bit(XPRT_CONNECTION_ABORT,
&xprt->state);
/* "close" the socket, preserving the local port */
+ set_bit(XPRT_CONNECTION_REUSE, &xprt->state);
xs_tcp_reuse_connection(transport);
+ clear_bit(XPRT_CONNECTION_REUSE, &xprt->state);

if (abort_and_exit)
goto out_eagain;
--
2.1.0

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