From patchwork Tue Mar 5 01:30:14 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Trond Myklebust X-Patchwork-Id: 10838847 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 974CD1390 for ; Tue, 5 Mar 2019 01:31:25 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 85D2C2B783 for ; Tue, 5 Mar 2019 01:31:25 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7A1292B79D; Tue, 5 Mar 2019 01:31:25 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 238932B783 for ; Tue, 5 Mar 2019 01:31:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726434AbfCEBbY (ORCPT ); Mon, 4 Mar 2019 20:31:24 -0500 Received: from mail-it1-f196.google.com ([209.85.166.196]:40088 "EHLO mail-it1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726095AbfCEBbY (ORCPT ); Mon, 4 Mar 2019 20:31:24 -0500 Received: by mail-it1-f196.google.com with SMTP id l139so1880445ita.5 for ; Mon, 04 Mar 2019 17:31:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:subject:date:message-id:mime-version :content-transfer-encoding; bh=nZRhqCSGAmuqPoKC3r6VvDIcMWODu7nvIwDgDx3PHGU=; b=XyWbUYLRF+jrk5TBB19U2x0WaVYpD0I92D4hpknETYgn0Hc5bBCf2L+2jiNjaAaiwH f8XuWZXObWWVliukZe0JzT4XMlmCRNTbzuZ/BZvFMrLhIaas3PrYaAoHLC67aCPrq6Ml +v9KrXdmuiFdybkttJPPI2V6prLJ1obmekUa0TjdJJid9wlFETnr56dM11V0NVZhnypW XyY7gxEuiqcBnADVCsiNcQnNeCAdZHcqitUnEVU6t05Ogkdu+UGydqtXl6FhxDkXP69O 4mXR+wyMR5NDOBJQAYVhDekEMHR7/y64UBm1Wssqr3WkTPE1aOhPqlLW2Wb8qTvQpw59 qptA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:mime-version :content-transfer-encoding; bh=nZRhqCSGAmuqPoKC3r6VvDIcMWODu7nvIwDgDx3PHGU=; b=GC1UD41k9hkEDxYfQ76Au1xCCoUvnlf/7ULbiOnys0x6WtZhdmkm26G0nRsikQsoFg Qqw8DO3n6d4QBzrZJO6llK+UAsfzIhW0Y2iZp7/mpsj+W8lednP4WXNm/4tzUaHHFQgB 7X0yBRWfCLqskMPlaTc4wHoYO1zcWZ3q4K+KUigY11fwn7f8ZteNrHLn+iswlnRmtyy7 dGHTpVRvyV+LNfFLVsQcziLizY1lxab1IpAtGhODBIVQX+3e4Fkgwin0GQjSY57kaVNx KUTegJpbVOk5hVSjRH1RkLrV71p8cPAplpvwVqIGkuqHho5I0GWVLfbHyX/CJP8JZIAG Cpgw== X-Gm-Message-State: APjAAAX5pW0i/IMgP1TW0Luob4GfJ5wO4vZVb0vh0YL1bpMOslR27H7G EZfOSeN8XLJl9uULMpwNJuDUNHw= X-Google-Smtp-Source: APXvYqwq5hK+N14TwCsKPYYkK3byMJQbwiiQIXmtsmht9IW8YhGhzvy9QCgmzbkZ9qUao0JavPdmdg== X-Received: by 2002:a24:73c5:: with SMTP id y188mr1325577itb.147.1551749482884; Mon, 04 Mar 2019 17:31:22 -0800 (PST) Received: from localhost.localdomain (c-68-40-189-247.hsd1.mi.comcast.net. [68.40.189.247]) by smtp.gmail.com with ESMTPSA id f26sm2901058ioh.1.2019.03.04.17.31.22 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 04 Mar 2019 17:31:22 -0800 (PST) From: Trond Myklebust X-Google-Original-From: Trond Myklebust To: linux-nfs@vger.kernel.org Subject: [PATCH 1/2] SUNRPC: Prevent thundering herd when the socket is not connected Date: Mon, 4 Mar 2019 20:30:14 -0500 Message-Id: <20190305013015.30109-1-trond.myklebust@hammerspace.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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 --- net/sunrpc/clnt.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index 241e8423fd0c..e7ae75a045c9 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -2003,6 +2003,12 @@ call_transmit(struct rpc_task *task) if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) { if (!xprt_prepare_transmit(task)) return; + /* Check that the connection is OK */ + if (!xprt_connected(task->tk_xprt) || + !xprt_bound(task->tk_xprt)) { + task->tk_action = call_bind; + return; + } xprt_transmit(task); } task->tk_action = call_transmit_status;