From a564b8f0398636ba30b07c0eaebdef7ff7837249 Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Tue, 31 Jul 2012 16:45:12 -0700 Subject: nfs: enable swap on NFS Implement the new swapfile a_ops for NFS and hook up ->direct_IO. This will set the NFS socket to SOCK_MEMALLOC and run socket reconnect under PF_MEMALLOC as well as reset SOCK_MEMALLOC before engaging the protocol ->connect() method. PF_MEMALLOC should allow the allocation of struct socket and related objects and the early (re)setting of SOCK_MEMALLOC should allow us to receive the packets required for the TCP connection buildup. [jlayton@redhat.com: Restore PF_MEMALLOC task flags in all cases] [dfeng@redhat.com: Fix handling of multiple swap files] [a.p.zijlstra@chello.nl: Original patch] Signed-off-by: Mel Gorman Acked-by: Rik van Riel Cc: Christoph Hellwig Cc: David S. Miller Cc: Eric B Munson Cc: Eric Paris Cc: James Morris Cc: Mel Gorman Cc: Mike Christie Cc: Neil Brown Cc: Sebastian Andrzej Siewior Cc: Trond Myklebust Cc: Xiaotian Feng Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- net/sunrpc/Kconfig | 5 +++++ net/sunrpc/clnt.c | 9 +++++++++ net/sunrpc/sched.c | 7 +++++-- net/sunrpc/xprtsock.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 62 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/sunrpc/Kconfig b/net/sunrpc/Kconfig index 9fe8857..03d03e3 100644 --- a/net/sunrpc/Kconfig +++ b/net/sunrpc/Kconfig @@ -21,6 +21,11 @@ config SUNRPC_XPRT_RDMA If unsure, say N. +config SUNRPC_SWAP + bool + depends on SUNRPC + select NETVM + config RPCSEC_GSS_KRB5 tristate "Secure RPC: Kerberos V mechanism" depends on SUNRPC && CRYPTO diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index b05df36..fa48c60 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -717,6 +717,15 @@ void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt) atomic_inc(&clnt->cl_count); if (clnt->cl_softrtry) task->tk_flags |= RPC_TASK_SOFT; + if (sk_memalloc_socks()) { + struct rpc_xprt *xprt; + + rcu_read_lock(); + xprt = rcu_dereference(clnt->cl_xprt); + if (xprt->swapper) + task->tk_flags |= RPC_TASK_SWAPPER; + rcu_read_unlock(); + } /* Add to the client's list of all tasks */ spin_lock(&clnt->cl_lock); list_add_tail(&task->tk_task, &clnt->cl_tasks); diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c index 994cfea..83a4c43 100644 --- a/net/sunrpc/sched.c +++ b/net/sunrpc/sched.c @@ -812,7 +812,10 @@ static void rpc_async_schedule(struct work_struct *work) void *rpc_malloc(struct rpc_task *task, size_t size) { struct rpc_buffer *buf; - gfp_t gfp = RPC_IS_SWAPPER(task) ? GFP_ATOMIC : GFP_NOWAIT; + gfp_t gfp = GFP_NOWAIT; + + if (RPC_IS_SWAPPER(task)) + gfp |= __GFP_MEMALLOC; size += sizeof(struct rpc_buffer); if (size <= RPC_BUFFER_MAXSIZE) @@ -886,7 +889,7 @@ static void rpc_init_task(struct rpc_task *task, const struct rpc_task_setup *ta static struct rpc_task * rpc_alloc_task(void) { - return (struct rpc_task *)mempool_alloc(rpc_task_mempool, GFP_NOFS); + return (struct rpc_task *)mempool_alloc(rpc_task_mempool, GFP_NOIO); } /* diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 62d0dac..bd59d01 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -1927,6 +1927,45 @@ out: xprt_wake_pending_tasks(xprt, status); } +#ifdef CONFIG_SUNRPC_SWAP +static void xs_set_memalloc(struct rpc_xprt *xprt) +{ + struct sock_xprt *transport = container_of(xprt, struct sock_xprt, + xprt); + + if (xprt->swapper) + sk_set_memalloc(transport->inet); +} + +/** + * xs_swapper - Tag this transport as being used for swap. + * @xprt: transport to tag + * @enable: enable/disable + * + */ +int xs_swapper(struct rpc_xprt *xprt, int enable) +{ + struct sock_xprt *transport = container_of(xprt, struct sock_xprt, + xprt); + int err = 0; + + if (enable) { + xprt->swapper++; + xs_set_memalloc(xprt); + } else if (xprt->swapper) { + xprt->swapper--; + sk_clear_memalloc(transport->inet); + } + + return err; +} +EXPORT_SYMBOL_GPL(xs_swapper); +#else +static void xs_set_memalloc(struct rpc_xprt *xprt) +{ +} +#endif + static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); @@ -1951,6 +1990,8 @@ static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock) transport->sock = sock; transport->inet = sk; + xs_set_memalloc(xprt); + write_unlock_bh(&sk->sk_callback_lock); } xs_udp_do_set_buffer_size(xprt); @@ -2075,6 +2116,8 @@ static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock) if (!xprt_bound(xprt)) goto out; + xs_set_memalloc(xprt); + /* Tell the socket layer to start connecting... */ xprt->stat.connect_count++; xprt->stat.connect_start = jiffies; -- cgit v1.1