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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 C08B3C433DF for ; Mon, 17 Aug 2020 19:24:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A2BAE20658 for ; Mon, 17 Aug 2020 19:24:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597692255; bh=0ay/RrJGtz7p5JCeEL2riGtfbb08ca11TFjXDHxvjic=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=lGSB6phcP2m6fPz2k+wVWZmfjElAVphX0bsCTOg4jKMm7DHcLEVjXbJm3qvU9AyhY V4VSpwCIZJ6vVblVegXwQheqiM02cvUGB40GwZhlP9sRwJ709UHQxJyBFGZ46i2tSb hnlsiQgettFOUM/Lw23833VhT7rj9CdqFmTUCKtY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731957AbgHQTYJ (ORCPT ); Mon, 17 Aug 2020 15:24:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:40854 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730442AbgHQPeu (ORCPT ); Mon, 17 Aug 2020 11:34:50 -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 AD22E22BEF; Mon, 17 Aug 2020 15:34:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597678489; bh=0ay/RrJGtz7p5JCeEL2riGtfbb08ca11TFjXDHxvjic=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RHNZ9JgpD1HlX+aDCDbhgyjQdHYT19n04f2F8OnCZPohWY7y6vA9gQ3HQP3yJ7GbG F6rMG7QDa4A5X9m0COBIM3oBQhoeLx3OobZ0vlj1YGIiexAKrgT4FB/nueiO22FFX8 Z+lRXgFflluE5MMHSWH7eH9AmNUgZRENo6K2/di8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Danil Kipnis , Md Haris Iqbal , Jason Gunthorpe , Sasha Levin Subject: [PATCH 5.8 320/464] RDMA/rtrs-clt: add an additional random 8 seconds before reconnecting Date: Mon, 17 Aug 2020 17:14:33 +0200 Message-Id: <20200817143849.125018827@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817143833.737102804@linuxfoundation.org> References: <20200817143833.737102804@linuxfoundation.org> User-Agent: quilt/0.66 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 From: Danil Kipnis [ Upstream commit 09e0dbbeed82e35ce2cd21e086a6fac934163e2a ] In order to avoid all the clients to start reconnecting at the same time schedule the reconnect dwork with a random jitter of +[0,8] seconds. Fixes: 6a98d71daea1 ("RDMA/rtrs: client: main functionality") Link: https://lore.kernel.org/r/20200724111508.15734-2-haris.iqbal@cloud.ionos.com Signed-off-by: Danil Kipnis Signed-off-by: Md Haris Iqbal Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin --- drivers/infiniband/ulp/rtrs/rtrs-clt.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c index 564388a85603f..5b31d3b03737c 100644 --- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c +++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c @@ -12,6 +12,7 @@ #include #include +#include #include "rtrs-clt.h" #include "rtrs-log.h" @@ -23,6 +24,12 @@ * leads to "false positives" failed reconnect attempts */ #define RTRS_RECONNECT_BACKOFF 1000 +/* + * Wait for additional random time between 0 and 8 seconds + * before starting to reconnect to avoid clients reconnecting + * all at once in case of a major network outage + */ +#define RTRS_RECONNECT_SEED 8 MODULE_DESCRIPTION("RDMA Transport Client"); MODULE_LICENSE("GPL"); @@ -306,7 +313,8 @@ static void rtrs_rdma_error_recovery(struct rtrs_clt_con *con) */ delay_ms = clt->reconnect_delay_sec * 1000; queue_delayed_work(rtrs_wq, &sess->reconnect_dwork, - msecs_to_jiffies(delay_ms)); + msecs_to_jiffies(delay_ms + + prandom_u32() % RTRS_RECONNECT_SEED)); } else { /* * Error can happen just on establishing new connection, @@ -2503,7 +2511,9 @@ static void rtrs_clt_reconnect_work(struct work_struct *work) sess->stats->reconnects.fail_cnt++; delay_ms = clt->reconnect_delay_sec * 1000; queue_delayed_work(rtrs_wq, &sess->reconnect_dwork, - msecs_to_jiffies(delay_ms)); + msecs_to_jiffies(delay_ms + + prandom_u32() % + RTRS_RECONNECT_SEED)); } } -- 2.25.1