Return-Path: Received: from mail-io0-f174.google.com ([209.85.223.174]:32807 "EHLO mail-io0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752487AbcBARV5 (ORCPT ); Mon, 1 Feb 2016 12:21:57 -0500 Received: by mail-io0-f174.google.com with SMTP id f81so164354061iof.0 for ; Mon, 01 Feb 2016 09:21:56 -0800 (PST) From: Trond Myklebust To: linux-nfs@vger.kernel.org Subject: [RFC PATCH v3 00/13] Basic multipathing support and demonstrator Date: Mon, 1 Feb 2016 12:21:04 -0500 Message-Id: <1454347277-10997-1-git-send-email-trond.myklebust@primarydata.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: Hi all, The following patchset is intended as an RFC to demonstrate how we could implement multipathing in NFS. It adds basic support for attaching multiple RPC transports to a client, an embryonic policy mechanism for switching tasks across those transports (with a round-robin policy implementation), as well as helpers to allow iteration of tasks across all tranports (for instance in order to support NFSv4.1's BIND_CONN_TO_SESSION). A lot of polish and finishing touches are missing. For instance, I have yet to add support in debugfs for these transports, and there is no support for mounting with NFSv4.1 session trunking. However there is a demonstrator that implements pNFS multipathing over NFSv3. Adding support for NFSv4.1 requires that you call EXCHANGE_ID to allow verification of the major/minor server and scopeid fields, which should not be too hard. More to come, but in the meantime, comments are welcome... Cheers Trond -------------- v2 & v3: Fix up kbuild warnings Trond Myklebust (13): SUNRPC: Remove unused function rpc_task_reset_client SUNRPC: Reorder rpc_task to put waitqueue related info in same cachelines SUNRPC: Uninline xprt_get(); It isn't performance critical. SUNRPC: Make freeing of struct xprt rcu-safe SUNRPC: Add a structure to track multiple transports SUNRPC: Make rpc_clnt store the multipath iterators SUNRPC: Use the multipath iterator to assign a transport to each task SUNRPC: Allow caller to specify the transport to use SUNRPC: Add a helper to apply a function to all the rpc_clnt's transports SUNRPC: Make NFS swap work with multipath NFSv4.1: nfs4_proc_bind_conn_to_session must iterate over all connections SUNRPC: Allow addition of new transports to a struct rpc_clnt pnfs/NFSv4.1: Add multipath capabilities to pNFS flexfiles servers over NFSv3 fs/nfs/nfs4proc.c | 51 +++- fs/nfs/pnfs_nfs.c | 16 +- include/linux/sunrpc/clnt.h | 18 +- include/linux/sunrpc/sched.h | 32 +-- include/linux/sunrpc/xprt.h | 22 +- include/linux/sunrpc/xprtmultipath.h | 69 +++++ net/sunrpc/Makefile | 3 +- net/sunrpc/auth_gss/auth_gss.c | 4 +- net/sunrpc/clnt.c | 326 ++++++++++++++++++------ net/sunrpc/rpcb_clnt.c | 10 +- net/sunrpc/sched.c | 2 + net/sunrpc/xprt.c | 42 ++-- net/sunrpc/xprtmultipath.c | 473 +++++++++++++++++++++++++++++++++++ net/sunrpc/xprtsock.c | 4 +- 14 files changed, 938 insertions(+), 134 deletions(-) create mode 100644 include/linux/sunrpc/xprtmultipath.h create mode 100644 net/sunrpc/xprtmultipath.c -- 2.5.0