From patchwork Tue May 26 15:51:17 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuck Lever III X-Patchwork-Id: 6482881 Return-Path: X-Original-To: patchwork-linux-rdma@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 497539F40A for ; Tue, 26 May 2015 15:51:54 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 7D5762038E for ; Tue, 26 May 2015 15:51:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7816120620 for ; Tue, 26 May 2015 15:51:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932389AbbEZPvZ (ORCPT ); Tue, 26 May 2015 11:51:25 -0400 Received: from mail-qg0-f53.google.com ([209.85.192.53]:36683 "EHLO mail-qg0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932380AbbEZPvV (ORCPT ); Tue, 26 May 2015 11:51:21 -0400 Received: by qgf2 with SMTP id 2so31691713qgf.3; Tue, 26 May 2015 08:51:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:subject:from:to:cc:date:message-id:in-reply-to:references :user-agent:mime-version:content-type:content-transfer-encoding; bh=yueSc8n3EGl2iFvb2cckNugzJZ2RmuV+/ZQieANFzZ4=; b=fKT6sx9/j4aNjryeTARKmAjzSo1qx9lkLR4Sg/27lK9U2PhpZFBBpg8mYzWSJMc33I 2X8i8Rc/g8n3sAI4CyIzG26q/1psDBLiJ1V0+7k/sY6FxHcZMyaSSFm1XzFVBGqbq0qC pNzb2eY01CQ2KJImH1UCZ1pKcElbW6OmsQi1CS1Z22TTLQLCK87JcyGPImdD/sZXZrb8 LLQjtPv0ElBI7e571kvVpMCDzz9HV55fp710exjX+ywp9XY2TuidpOYe8aDX4BwnnHvH D38ZOhHRtyt/zfIn8AnLgwA48JK5OYbrAd7JC/R0ZwSxLmd5Rr6N8uTFVCt7cYRuadQ1 EseQ== X-Received: by 10.55.22.143 with SMTP id 15mr591424qkw.85.1432655480408; Tue, 26 May 2015 08:51:20 -0700 (PDT) Received: from manet.1015granger.net ([2604:8800:100:81fc:82ee:73ff:fe43:d64f]) by mx.google.com with ESMTPSA id k69sm8896973qkh.48.2015.05.26.08.51.18 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 26 May 2015 08:51:19 -0700 (PDT) Subject: [PATCH v3 01/17] SUNRPC: Transport fault injection From: Chuck Lever To: Anna.Schumaker@netapp.com Cc: linux-rdma@vger.kernel.org, linux-nfs@vger.kernel.org Date: Tue, 26 May 2015 11:51:17 -0400 Message-ID: <20150526155117.4542.31183.stgit@manet.1015granger.net> In-Reply-To: <20150526153926.4542.96409.stgit@manet.1015granger.net> References: <20150526153926.4542.96409.stgit@manet.1015granger.net> User-Agent: StGit/0.17.1-3-g7d0f MIME-Version: 1.0 Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org X-Spam-Status: No, score=-6.8 required=5.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID,T_RP_MATCHES_RCVD,UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP It has been exceptionally useful to exercise the logic that handles local immediate errors and RDMA connection loss. To enable developers to test this regularly and repeatably, add logic to simulate connection loss every so often. Fault injection is disabled by default. It is enabled with $ sudo echo xxx > /sys/kernel/debug/sunrpc/inject_fault/disconnect where "xxx" is a large positive number of transport method calls before a disconnect. A value of several thousand is usually a good number that allows reasonable forward progress while still causing a lot of connection drops. These hooks are disabled when SUNRPC_DEBUG is turned off. Signed-off-by: Chuck Lever Tested-By: Devesh Sharma Reviewed-by: Doug Ledford --- include/linux/sunrpc/xprt.h | 19 ++++++++++ net/sunrpc/clnt.c | 1 + net/sunrpc/debugfs.c | 77 +++++++++++++++++++++++++++++++++++++++ net/sunrpc/xprt.c | 2 + net/sunrpc/xprtrdma/transport.c | 13 ++++++- net/sunrpc/xprtsock.c | 10 +++++ 6 files changed, 121 insertions(+), 1 deletion(-) -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h index 8b93ef5..178190a 100644 --- a/include/linux/sunrpc/xprt.h +++ b/include/linux/sunrpc/xprt.h @@ -133,6 +133,7 @@ struct rpc_xprt_ops { void (*close)(struct rpc_xprt *xprt); void (*destroy)(struct rpc_xprt *xprt); void (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq); + void (*inject_disconnect)(struct rpc_xprt *xprt); }; /* @@ -241,6 +242,7 @@ struct rpc_xprt { const char *address_strings[RPC_DISPLAY_MAX]; #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) struct dentry *debugfs; /* debugfs directory */ + atomic_t inject_disconnect; #endif }; @@ -431,6 +433,23 @@ static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt) return test_and_set_bit(XPRT_BINDING, &xprt->state); } +#if IS_ENABLED(CONFIG_SUNRPC_DEBUG) +extern unsigned int rpc_inject_disconnect; +static inline void xprt_inject_disconnect(struct rpc_xprt *xprt) +{ + if (!rpc_inject_disconnect) + return; + if (atomic_dec_return(&xprt->inject_disconnect)) + return; + atomic_set(&xprt->inject_disconnect, rpc_inject_disconnect); + xprt->ops->inject_disconnect(xprt); +} +#else +static inline void xprt_inject_disconnect(struct rpc_xprt *xprt) +{ +} +#endif + #endif /* __KERNEL__*/ #endif /* _LINUX_SUNRPC_XPRT_H */ diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index e6ce151..db4efb6 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -1614,6 +1614,7 @@ call_allocate(struct rpc_task *task) req->rq_callsize + req->rq_rcvsize); if (req->rq_buffer != NULL) return; + xprt_inject_disconnect(xprt); dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid); diff --git a/net/sunrpc/debugfs.c b/net/sunrpc/debugfs.c index 82962f7..7cc1b8a 100644 --- a/net/sunrpc/debugfs.c +++ b/net/sunrpc/debugfs.c @@ -10,9 +10,12 @@ #include "netns.h" static struct dentry *topdir; +static struct dentry *rpc_fault_dir; static struct dentry *rpc_clnt_dir; static struct dentry *rpc_xprt_dir; +unsigned int rpc_inject_disconnect; + struct rpc_clnt_iter { struct rpc_clnt *clnt; loff_t pos; @@ -257,6 +260,8 @@ rpc_xprt_debugfs_register(struct rpc_xprt *xprt) debugfs_remove_recursive(xprt->debugfs); xprt->debugfs = NULL; } + + atomic_set(&xprt->inject_disconnect, rpc_inject_disconnect); } void @@ -266,11 +271,78 @@ rpc_xprt_debugfs_unregister(struct rpc_xprt *xprt) xprt->debugfs = NULL; } +static int +fault_open(struct inode *inode, struct file *filp) +{ + filp->private_data = kmalloc(128, GFP_KERNEL); + if (!filp->private_data) + return -ENOMEM; + return 0; +} + +static int +fault_release(struct inode *inode, struct file *filp) +{ + kfree(filp->private_data); + return 0; +} + +static ssize_t +fault_disconnect_read(struct file *filp, char __user *user_buf, + size_t len, loff_t *offset) +{ + char *buffer = (char *)filp->private_data; + size_t size; + + size = sprintf(buffer, "%u\n", rpc_inject_disconnect); + return simple_read_from_buffer(user_buf, len, offset, buffer, size); +} + +static ssize_t +fault_disconnect_write(struct file *filp, const char __user *user_buf, + size_t len, loff_t *offset) +{ + char buffer[16]; + + len = min(len, sizeof(buffer) - 1); + if (copy_from_user(buffer, user_buf, len)) + return -EFAULT; + buffer[len] = '\0'; + if (kstrtouint(buffer, 10, &rpc_inject_disconnect)) + return -EINVAL; + return len; +} + +static const struct file_operations fault_disconnect_fops = { + .owner = THIS_MODULE, + .open = fault_open, + .read = fault_disconnect_read, + .write = fault_disconnect_write, + .release = fault_release, +}; + +static struct dentry * +inject_fault_dir(struct dentry *topdir) +{ + struct dentry *faultdir; + + faultdir = debugfs_create_dir("inject_fault", topdir); + if (!faultdir) + return NULL; + + if (!debugfs_create_file("disconnect", S_IFREG | S_IRUSR, faultdir, + NULL, &fault_disconnect_fops)) + return NULL; + + return faultdir; +} + void __exit sunrpc_debugfs_exit(void) { debugfs_remove_recursive(topdir); topdir = NULL; + rpc_fault_dir = NULL; rpc_clnt_dir = NULL; rpc_xprt_dir = NULL; } @@ -282,6 +354,10 @@ sunrpc_debugfs_init(void) if (!topdir) return; + rpc_fault_dir = inject_fault_dir(topdir); + if (!rpc_fault_dir) + goto out_remove; + rpc_clnt_dir = debugfs_create_dir("rpc_clnt", topdir); if (!rpc_clnt_dir) goto out_remove; @@ -294,5 +370,6 @@ sunrpc_debugfs_init(void) out_remove: debugfs_remove_recursive(topdir); topdir = NULL; + rpc_fault_dir = NULL; rpc_clnt_dir = NULL; } diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c index 1d4fe24..e1fb538 100644 --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -967,6 +967,7 @@ void xprt_transmit(struct rpc_task *task) task->tk_status = status; return; } + xprt_inject_disconnect(xprt); dprintk("RPC: %5u xmit complete\n", task->tk_pid); task->tk_flags |= RPC_TASK_SENT; @@ -1285,6 +1286,7 @@ void xprt_release(struct rpc_task *task) spin_unlock_bh(&xprt->transport_lock); if (req->rq_buffer) xprt->ops->buf_free(req->rq_buffer); + xprt_inject_disconnect(xprt); if (req->rq_cred != NULL) put_rpccred(req->rq_cred); task->tk_rqstp = NULL; diff --git a/net/sunrpc/xprtrdma/transport.c b/net/sunrpc/xprtrdma/transport.c index 54f23b1..dfcd52e 100644 --- a/net/sunrpc/xprtrdma/transport.c +++ b/net/sunrpc/xprtrdma/transport.c @@ -246,6 +246,16 @@ xprt_rdma_connect_worker(struct work_struct *work) xprt_clear_connecting(xprt); } +static void +xprt_rdma_inject_disconnect(struct rpc_xprt *xprt) +{ + struct rpcrdma_xprt *r_xprt = container_of(xprt, struct rpcrdma_xprt, + rx_xprt); + + pr_info("rpcrdma: injecting transport disconnect on xprt=%p\n", xprt); + rdma_disconnect(r_xprt->rx_ia.ri_id); +} + /* * xprt_rdma_destroy * @@ -700,7 +710,8 @@ static struct rpc_xprt_ops xprt_rdma_procs = { .send_request = xprt_rdma_send_request, .close = xprt_rdma_close, .destroy = xprt_rdma_destroy, - .print_stats = xprt_rdma_print_stats + .print_stats = xprt_rdma_print_stats, + .inject_disconnect = xprt_rdma_inject_disconnect }; static struct xprt_class xprt_rdma = { diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 66891e3..a0e7138 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -863,6 +863,13 @@ static void xs_close(struct rpc_xprt *xprt) xprt_disconnect_done(xprt); } +static void xs_inject_disconnect(struct rpc_xprt *xprt) +{ + dprintk("RPC: injecting transport disconnect on xprt=%p\n", + xprt); + xprt_disconnect_done(xprt); +} + static void xs_xprt_free(struct rpc_xprt *xprt) { xs_free_peer_addresses(xprt); @@ -2482,6 +2489,7 @@ static struct rpc_xprt_ops xs_udp_ops = { .close = xs_close, .destroy = xs_destroy, .print_stats = xs_udp_print_stats, + .inject_disconnect = xs_inject_disconnect, }; static struct rpc_xprt_ops xs_tcp_ops = { @@ -2498,6 +2506,7 @@ static struct rpc_xprt_ops xs_tcp_ops = { .close = xs_tcp_shutdown, .destroy = xs_destroy, .print_stats = xs_tcp_print_stats, + .inject_disconnect = xs_inject_disconnect, }; /* @@ -2515,6 +2524,7 @@ static struct rpc_xprt_ops bc_tcp_ops = { .close = bc_close, .destroy = bc_destroy, .print_stats = xs_tcp_print_stats, + .inject_disconnect = xs_inject_disconnect, }; static int xs_init_anyaddr(const int family, struct sockaddr *sap)