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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_MUTT 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 2B700C43613 for ; Mon, 24 Jun 2019 20:17:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E52C320657 for ; Mon, 24 Jun 2019 20:17:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561407447; bh=V5CX1ldDiziORU4wtHIlX3WC7pmIIArB1gRa+JVxG2Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=qnEvHxqv1kdPKKfo9bGwsjr0LAjqeJkgm4Zcfp86RrugTZIcS/hRWAF3Ina+QTAmg N/rd+a8DxRPvD+gcWDtz+qWnn0YS7PXdz+O3VNTtp8WdhRDc6jKNwwl4IpeTzmU5sX e3QHLVNq8+CDMMuPj71ZdtBl29d81/3RA3K4m5uA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727857AbfFXUR0 (ORCPT ); Mon, 24 Jun 2019 16:17:26 -0400 Received: from mail.kernel.org ([198.145.29.99]:47598 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727089AbfFXUR0 (ORCPT ); Mon, 24 Jun 2019 16:17:26 -0400 Received: from localhost (unknown [167.220.24.221]) (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 3A78B20645; Mon, 24 Jun 2019 20:17:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561407445; bh=V5CX1ldDiziORU4wtHIlX3WC7pmIIArB1gRa+JVxG2Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=vFEzqPncGMYeYqi2GzJ6NCpWua/9rvy3zjT7ciFLkgbLNUixN7ir2aZXD6Gk78l8F Y7YBlNaYkd+7rJeD2kAhHvBDa7zYZqniSJL4FvNA8aeYNAFZ6/a0IZqxqQt3LNUHKr M/LHSCkKVrtyypUjLr6/3xDQJI6tGFJ0VbjkH6f8= Date: Mon, 24 Jun 2019 16:17:24 -0400 From: Sasha Levin To: Mike Marciniszyn Cc: stable@vger.kernel.org, linux-rdma@vger.kernel.org, stable-commits@vger.kernel.org Subject: Re: [PATCH] IB/hfi1: Avoid hardlockup with flushlist_lock Message-ID: <20190624201724.GA3881@sasha-vm> References: <20190624161428.17461.31880.stgit@awfm-01.aw.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20190624161428.17461.31880.stgit@awfm-01.aw.intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Mon, Jun 24, 2019 at 12:14:29PM -0400, Mike Marciniszyn wrote: >commit cf131a81967583ae737df6383a0893b9fee75b4e upstream. > >Heavy contention of the sde flushlist_lock can cause hard lockups at >extreme scale when the flushing logic is under stress. > >Mitigate by replacing the item at a time copy to the local list with >an O(1) list_splice_init() and using the high priority work queue to >do the flushes. > >Ported to linux-4.14.y. I've queued this one for 4.19 and 4.14, thank you. -- Thanks, Sasha