From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752410AbeCPQXi (ORCPT ); Fri, 16 Mar 2018 12:23:38 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:39622 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754648AbeCPQRE (ORCPT ); Fri, 16 Mar 2018 12:17:04 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 9702A60F93 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=okaya@codeaurora.org From: Sinan Kaya To: netdev@vger.kernel.org, timur@codeaurora.org, sulrich@codeaurora.org Cc: linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Sinan Kaya , Dept-GELinuxNICDev@cavium.com, linux-kernel@vger.kernel.org Subject: [PATCH v3 10/18] net: qla3xxx: Eliminate duplicate barriers on weakly-ordered archs Date: Fri, 16 Mar 2018 12:16:23 -0400 Message-Id: <1521216991-28706-11-git-send-email-okaya@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1521216991-28706-1-git-send-email-okaya@codeaurora.org> References: <1521216991-28706-1-git-send-email-okaya@codeaurora.org> MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Code includes wmb() followed by writel(). writel() already has a barrier on some architectures like arm64. This ends up CPU observing two barriers back to back before executing the register write. Since code already has an explicit barrier call, changing writel() to writel_relaxed(). Signed-off-by: Sinan Kaya --- drivers/net/ethernet/qlogic/qla3xxx.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/qlogic/qla3xxx.c b/drivers/net/ethernet/qlogic/qla3xxx.c index 9e5264d..0e71b74 100644 --- a/drivers/net/ethernet/qlogic/qla3xxx.c +++ b/drivers/net/ethernet/qlogic/qla3xxx.c @@ -1858,8 +1858,8 @@ static void ql_update_small_bufq_prod_index(struct ql3_adapter *qdev) qdev->small_buf_release_cnt -= 8; } wmb(); - writel(qdev->small_buf_q_producer_index, - &port_regs->CommonRegs.rxSmallQProducerIndex); + writel_relaxed(qdev->small_buf_q_producer_index, + &port_regs->CommonRegs.rxSmallQProducerIndex); } } -- 2.7.4