From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 073ADC43381 for ; Fri, 22 Mar 2019 12:24:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C8E952054F for ; Fri, 22 Mar 2019 12:24:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553257490; bh=ZnHAij9gG4Hk3sBecLQ9HLx75XVOT1v67/qlEBoLm1Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=eIlK8OCaL72GCx7Yg5cflYhJL2vRDhX4qdi4KVBmq/PzI3hwd//6QDw7Mra4ne+fI UVxYVnc+wCSVV0LSAHcnnIdKqq7oi+tinJmREa0kHjQxQiJoGLcqPqaL6thIfZWFEe wV9zcCr/vezjQT0WCF352CquwiHUthQ3iFlPE/xQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390953AbfCVMYt (ORCPT ); Fri, 22 Mar 2019 08:24:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:36688 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2403804AbfCVMYm (ORCPT ); Fri, 22 Mar 2019 08:24:42 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E51DC21917; Fri, 22 Mar 2019 12:24:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553257481; bh=ZnHAij9gG4Hk3sBecLQ9HLx75XVOT1v67/qlEBoLm1Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=C1NBRqimB5Q2mfzEY2ZBosA4x0C0tIe69SgRv02tbhuBDgcqxQt7zSxSNHjOTzPv2 jyjq+IjzP4ftkuUKgRHL/gpO70TMaMyHIa4u1+JMFMAYKlsBIF59Gm2MDbWcNmZJS+ 2f1i9MmNdQuqz2kucTwcd7/H/1W6QC688G2HHcZY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Trond Myklebust Subject: [PATCH 5.0 236/238] SUNRPC: Prevent thundering herd when the socket is not connected Date: Fri, 22 Mar 2019 12:17:35 +0100 Message-Id: <20190322111312.358290131@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190322111258.383569278@linuxfoundation.org> References: <20190322111258.383569278@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 5.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Trond Myklebust commit ed7dc973bd91da234d93aff6d033a5206a6c9885 upstream. If the socket is not connected, then we want to initiate a reconnect rather that trying to transmit requests. If there is a large number of requests queued and waiting for the lock in call_transmit(), then it can take a while for one of the to loop back and retake the lock in call_connect. Fixes: 89f90fe1ad8b ("SUNRPC: Allow calls to xprt_transmit() to drain...") Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman --- net/sunrpc/clnt.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -1786,7 +1786,12 @@ call_encode(struct rpc_task *task) xprt_request_enqueue_receive(task); xprt_request_enqueue_transmit(task); out: - task->tk_action = call_bind; + task->tk_action = call_transmit; + /* Check that the connection is OK */ + if (!xprt_bound(task->tk_xprt)) + task->tk_action = call_bind; + else if (!xprt_connected(task->tk_xprt)) + task->tk_action = call_connect; } /* @@ -1978,13 +1983,19 @@ call_transmit(struct rpc_task *task) { dprint_status(task); - task->tk_status = 0; + task->tk_action = call_transmit_status; if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) { if (!xprt_prepare_transmit(task)) return; - xprt_transmit(task); + task->tk_status = 0; + if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) { + if (!xprt_connected(task->tk_xprt)) { + task->tk_status = -ENOTCONN; + return; + } + xprt_transmit(task); + } } - task->tk_action = call_transmit_status; xprt_end_transmit(task); } @@ -2046,6 +2057,8 @@ call_transmit_status(struct rpc_task *ta case -EADDRINUSE: case -ENOTCONN: case -EPIPE: + task->tk_action = call_bind; + task->tk_status = 0; break; } }