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[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