From 8d480326c3d6921ff5f1cc988c993bd572248deb Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 5 Aug 2016 19:03:31 -0400 Subject: NFSv4: Cap the transport reconnection timer at 1/2 lease period We don't want to miss a lease period renewal due to the TCP connection failing to reconnect in a timely fashion. To ensure this doesn't happen, cap the reconnection timer so that we retry the connection attempt at least every 1/2 lease period. Signed-off-by: Trond Myklebust --- fs/nfs/nfs4renewd.c | 3 +++ include/linux/sunrpc/clnt.h | 2 ++ net/sunrpc/clnt.c | 21 +++++++++++++++++++++ 3 files changed, 26 insertions(+) diff --git a/fs/nfs/nfs4renewd.c b/fs/nfs/nfs4renewd.c index 062029ab344a..82e77198d17e 100644 --- a/fs/nfs/nfs4renewd.c +++ b/fs/nfs/nfs4renewd.c @@ -151,6 +151,9 @@ void nfs4_set_lease_period(struct nfs_client *clp, clp->cl_lease_time = lease; clp->cl_last_renewal = lastrenewed; spin_unlock(&clp->cl_lock); + + /* Cap maximum reconnect timeout at 1/2 lease period */ + rpc_cap_max_reconnect_timeout(clp->cl_rpcclient, lease >> 1); } /* diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h index b6810c92b8bb..5c02b0691587 100644 --- a/include/linux/sunrpc/clnt.h +++ b/include/linux/sunrpc/clnt.h @@ -195,6 +195,8 @@ int rpc_clnt_add_xprt(struct rpc_clnt *, struct xprt_create *, struct rpc_xprt *, void *), void *data); +void rpc_cap_max_reconnect_timeout(struct rpc_clnt *clnt, + unsigned long timeo); const char *rpc_proc_name(const struct rpc_task *task); #endif /* __KERNEL__ */ diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index faac5472d14d..7f79fb7dc6a0 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -2676,6 +2676,27 @@ out_put_switch: } EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt); +static int +rpc_xprt_cap_max_reconnect_timeout(struct rpc_clnt *clnt, + struct rpc_xprt *xprt, + void *data) +{ + unsigned long timeout = *((unsigned long *)data); + + if (timeout < xprt->max_reconnect_timeout) + xprt->max_reconnect_timeout = timeout; + return 0; +} + +void +rpc_cap_max_reconnect_timeout(struct rpc_clnt *clnt, unsigned long timeo) +{ + rpc_clnt_iterate_for_each_xprt(clnt, + rpc_xprt_cap_max_reconnect_timeout, + &timeo); +} +EXPORT_SYMBOL_GPL(rpc_cap_max_reconnect_timeout); + #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) static void rpc_show_header(void) { -- cgit v1.2.3