From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sinan Kaya Subject: [PATCH v6 2/6] qlcnic: Eliminate duplicate barriers on weakly-ordered archs Date: Fri, 23 Mar 2018 18:23:07 -0400 Message-ID: <1521843791-21201-3-git-send-email-okaya@codeaurora.org> References: <1521843791-21201-1-git-send-email-okaya@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1521843791-21201-1-git-send-email-okaya@codeaurora.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: netdev@vger.kernel.org, timur@codeaurora.org, sulrich@codeaurora.org Cc: Dept-GELinuxNICDev@cavium.com, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, Sinan Kaya , Harish Patil , linux-arm-kernel@lists.infradead.org, Manish Chopra List-Id: linux-arm-msm@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 Acked-by: Manish Chopra --- drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c index 46b0372..97c146e7 100644 --- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c +++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c @@ -478,7 +478,7 @@ irqreturn_t qlcnic_83xx_clear_legacy_intr(struct qlcnic_adapter *adapter) wmb(); /* clear the interrupt trigger control register */ - writel(0, adapter->isr_int_vec); + writel_relaxed(0, adapter->isr_int_vec); intr_val = readl(adapter->isr_int_vec); do { intr_val = readl(adapter->tgt_status_reg); -- 2.7.4 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752706AbeCWWZV (ORCPT ); Fri, 23 Mar 2018 18:25:21 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:35708 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751899AbeCWWXU (ORCPT ); Fri, 23 Mar 2018 18:23:20 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 15BA960312 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 , Harish Patil , Manish Chopra , Dept-GELinuxNICDev@cavium.com, linux-kernel@vger.kernel.org Subject: [PATCH v6 2/6] qlcnic: Eliminate duplicate barriers on weakly-ordered archs Date: Fri, 23 Mar 2018 18:23:07 -0400 Message-Id: <1521843791-21201-3-git-send-email-okaya@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1521843791-21201-1-git-send-email-okaya@codeaurora.org> References: <1521843791-21201-1-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 Acked-by: Manish Chopra --- drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c index 46b0372..97c146e7 100644 --- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c +++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c @@ -478,7 +478,7 @@ irqreturn_t qlcnic_83xx_clear_legacy_intr(struct qlcnic_adapter *adapter) wmb(); /* clear the interrupt trigger control register */ - writel(0, adapter->isr_int_vec); + writel_relaxed(0, adapter->isr_int_vec); intr_val = readl(adapter->isr_int_vec); do { intr_val = readl(adapter->tgt_status_reg); -- 2.7.4 From mboxrd@z Thu Jan 1 00:00:00 1970 From: okaya@codeaurora.org (Sinan Kaya) Date: Fri, 23 Mar 2018 18:23:07 -0400 Subject: [PATCH v6 2/6] qlcnic: Eliminate duplicate barriers on weakly-ordered archs In-Reply-To: <1521843791-21201-1-git-send-email-okaya@codeaurora.org> References: <1521843791-21201-1-git-send-email-okaya@codeaurora.org> Message-ID: <1521843791-21201-3-git-send-email-okaya@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.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 Acked-by: Manish Chopra --- drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c index 46b0372..97c146e7 100644 --- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c +++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c @@ -478,7 +478,7 @@ irqreturn_t qlcnic_83xx_clear_legacy_intr(struct qlcnic_adapter *adapter) wmb(); /* clear the interrupt trigger control register */ - writel(0, adapter->isr_int_vec); + writel_relaxed(0, adapter->isr_int_vec); intr_val = readl(adapter->isr_int_vec); do { intr_val = readl(adapter->tgt_status_reg); -- 2.7.4