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=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 84B0EC43219 for ; Mon, 29 Apr 2019 23:17:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 88F5F215EA for ; Mon, 29 Apr 2019 23:17:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amarulasolutions.com header.i=@amarulasolutions.com header.b="ofZYrEPW" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729200AbfD2XRH (ORCPT ); Mon, 29 Apr 2019 19:17:07 -0400 Received: from mail-wm1-f65.google.com ([209.85.128.65]:50578 "EHLO mail-wm1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729015AbfD2XRH (ORCPT ); Mon, 29 Apr 2019 19:17:07 -0400 Received: by mail-wm1-f65.google.com with SMTP id p21so1422849wmc.0 for ; Mon, 29 Apr 2019 16:17:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amarulasolutions.com; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=JYx/PpUETf62rnmWyBuVYJne6sL4Sppeoe68UBu+C48=; b=ofZYrEPWt3bOdtLGI4gwtxKCfg1DysFTX6WH2zp9NWFz4iSq/7S8g6I5rFTdm5lBTp olAIovsqhJvbvwceg95f+xrWfROSL61Q2fMufVhSmYbZEJbpAXHkWNXebH9MmbE9yXqK FARDvfWDj9MT//C1OTJ/dGMi5pWW61L6WcYx4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=JYx/PpUETf62rnmWyBuVYJne6sL4Sppeoe68UBu+C48=; b=My0L/xXC1BFZf//YsQVj+WRl9WS/FOP9t8595RsROCOO/nHC9hesHXyHU5EuVfNHGE 0VEgp5j3uPlWVaH+xkE7WipWKJ2qufzzKug8nGJsKI00jPDP8ToFgmSKEEy0nzdvyCJ8 8QTaY/QojrIuQ88aCbQW5A5ojH9mFFTNmYIRb2K2KIyY4NH4vyCd0Lna9Pt1JoMszWD8 a35OhVqPoGICIih+vGsXRj8e8j4ubaoWoQQCVpFiBsM6nGj1tciUffKd4fv1PyOhANYt DT0YTJA//5N9ghO7ljBTH2JYuliSvnf0Wv7kkk1TmsXDNSq83ycStVqCt1TeGba36nMR t2EA== X-Gm-Message-State: APjAAAXxF/RhnxSQJd1kGDsQYrisjX0O21jvTao2HNIvmHXYNdIYOqAM Al5RQc4AiXzC54PazxG9uYXra0wNUYs= X-Google-Smtp-Source: APXvYqwWNE+lo2Lmp4qExHW5Coy5MDuwao1zLqsY/frUnjQhkdUMLFonDKJe9juMWfTUs9n51gbhVQ== X-Received: by 2002:a1c:3cc2:: with SMTP id j185mr982553wma.26.1556579825704; Mon, 29 Apr 2019 16:17:05 -0700 (PDT) Received: from andrea (ip-93-97.sn2.clouditalia.com. [83.211.93.97]) by smtp.gmail.com with ESMTPSA id z11sm848336wmf.12.2019.04.29.16.17.04 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 29 Apr 2019 16:17:04 -0700 (PDT) Date: Tue, 30 Apr 2019 01:16:57 +0200 From: Andrea Parri To: "Ruhl, Michael J" Cc: "linux-kernel@vger.kernel.org" , "Dalessandro, Dennis" , "Marciniszyn, Mike" , Doug Ledford , Jason Gunthorpe , "linux-rdma@vger.kernel.org" Subject: Re: [PATCH 5/5] IB/hfi1: Fix improper uses of smp_mb__before_atomic() Message-ID: <20190429231657.GA2733@andrea> References: <1556568902-12464-1-git-send-email-andrea.parri@amarulasolutions.com> <1556568902-12464-6-git-send-email-andrea.parri@amarulasolutions.com> <14063C7AD467DE4B82DEDB5C278E8663BE6AADCE@FMSMSX108.amr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <14063C7AD467DE4B82DEDB5C278E8663BE6AADCE@FMSMSX108.amr.corp.intel.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Mike, > >This barrier only applies to the read-modify-write operations; in > >particular, it does not apply to the atomic_read() primitive. > > > >Replace the barrier with an smp_mb(). > > This is one of a couple of barrier issues that we are currently looking into. > > See: > > [PATCH for-next 6/9] IB/rdmavt: Add new completion inline > > We will take a look at this one as well. Thank you for the reference and for looking into this, Andrea