From patchwork Wed Mar 14 03:20:25 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sinan Kaya X-Patchwork-Id: 885595 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=codeaurora.org header.i=@codeaurora.org header.b="koXc+qD/"; dkim=pass (1024-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="koXc+qD/"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 401H7g6yL6z9sV5 for ; Wed, 14 Mar 2018 14:21:35 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933430AbeCNDUp (ORCPT ); Tue, 13 Mar 2018 23:20:45 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:43286 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932937AbeCNDUk (ORCPT ); Tue, 13 Mar 2018 23:20:40 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 6C4F26081A; Wed, 14 Mar 2018 03:20:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1520997640; bh=RhVMVKbH39d3U/MmgycBImExeegGH/1vCCzF6pwBT/o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=koXc+qD/VUXey5SYjMf9ewah+wXy1b1/hsAenO0nb5mK9PuP9id4vu90l3N2U4K2Z QGI+lWmTDYQHdHURcMl8IqxLCn7uXYrM2F4kFUYUDsGygGrSsDSgSNwVpAa/f583wt c4QC1lerdJG0l+l89CIT3e/tbOaNugIAji3Hl2i4= X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on pdx-caf-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.8 required=2.0 tests=ALL_TRUSTED,BAYES_00, DKIM_SIGNED, T_DKIM_INVALID autolearn=no autolearn_force=no version=3.4.0 Received: from drakthul.qualcomm.com (global_nat1_iad_fw.qualcomm.com [129.46.232.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: okaya@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 312B86083C; Wed, 14 Mar 2018 03:20:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1520997640; bh=RhVMVKbH39d3U/MmgycBImExeegGH/1vCCzF6pwBT/o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=koXc+qD/VUXey5SYjMf9ewah+wXy1b1/hsAenO0nb5mK9PuP9id4vu90l3N2U4K2Z QGI+lWmTDYQHdHURcMl8IqxLCn7uXYrM2F4kFUYUDsGygGrSsDSgSNwVpAa/f583wt c4QC1lerdJG0l+l89CIT3e/tbOaNugIAji3Hl2i4= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 312B86083C 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 , Jeff Kirsher , intel-wired-lan@lists.osuosl.org, linux-kernel@vger.kernel.org Subject: [PATCH 4/7] igbvf: eliminate duplicate barriers on weakly-ordered archs Date: Tue, 13 Mar 2018 23:20:25 -0400 Message-Id: <1520997629-17361-4-git-send-email-okaya@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1520997629-17361-1-git-send-email-okaya@codeaurora.org> References: <1520997629-17361-1-git-send-email-okaya@codeaurora.org> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@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/intel/igbvf/netdev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/igbvf/netdev.c b/drivers/net/ethernet/intel/igbvf/netdev.c index 4214c15..fe3441b 100644 --- a/drivers/net/ethernet/intel/igbvf/netdev.c +++ b/drivers/net/ethernet/intel/igbvf/netdev.c @@ -251,7 +251,7 @@ static void igbvf_alloc_rx_buffers(struct igbvf_ring *rx_ring, * such as IA-64). */ wmb(); - writel(i, adapter->hw.hw_addr + rx_ring->tail); + writel_relaxed(i, adapter->hw.hw_addr + rx_ring->tail); } }