Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S976461AbdDXSFI (ORCPT ); Mon, 24 Apr 2017 14:05:08 -0400 Received: from shards.monkeyblade.net ([184.105.139.130]:55498 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S975067AbdDXSE5 (ORCPT ); Mon, 24 Apr 2017 14:04:57 -0400 Date: Mon, 24 Apr 2017 14:04:55 -0400 (EDT) Message-Id: <20170424.140455.190776456596552748.davem@davemloft.net> To: khoroshilov@ispras.ru Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, ldv-project@linuxtesting.org Subject: Re: [PATCH v2] net: natsemi: ns83820: add checks for dma mapping error From: David Miller In-Reply-To: <1492866365-5422-1-git-send-email-khoroshilov@ispras.ru> References: <20170417.151743.1779341653983811894.davem@davemloft.net> <1492866365-5422-1-git-send-email-khoroshilov@ispras.ru> X-Mailer: Mew version 6.7 on Emacs 24.5 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Mon, 24 Apr 2017 10:23:33 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 207 Lines: 6 From: Alexey Khoroshilov Date: Sat, 22 Apr 2017 16:06:05 +0300 > + free_idx = (free_idx + NR_TX_DESC - 1) % NR_TX_DESC; This is more simply stated as "(free_idx - 1) % NR_TX_DESC.