From patchwork Sat Sep 3 09:59:26 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Wang X-Patchwork-Id: 9311943 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 11F3D60756 for ; Sat, 3 Sep 2016 10:00:05 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 029C2292F2 for ; Sat, 3 Sep 2016 10:00:05 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id EB66A292FB; Sat, 3 Sep 2016 10:00:04 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id A1E31292F2 for ; Sat, 3 Sep 2016 10:00:02 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1bg7k1-0003ns-Dh; Sat, 03 Sep 2016 10:00:01 +0000 Received: from [210.61.82.183] (helo=mailgw01.mediatek.com) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1bg7jy-0003Xf-Ic for linux-mediatek@lists.infradead.org; Sat, 03 Sep 2016 09:59:59 +0000 Received: from mtkhts07.mediatek.inc [(172.21.101.69)] by mailgw01.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 1579029180; Sat, 03 Sep 2016 17:59:32 +0800 Received: from mtkswgap22.mediatek.inc (172.21.77.33) by mtkhts07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 14.3.266.1; Sat, 3 Sep 2016 17:59:31 +0800 From: To: , Subject: [PATCH net-next v5 1/2] net: ethernet: mediatek: enhance RX path by reducing the frequency of the memory barrier used Date: Sat, 3 Sep 2016 17:59:26 +0800 Message-ID: <1472896767-18352-2-git-send-email-sean.wang@mediatek.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1472896767-18352-1-git-send-email-sean.wang@mediatek.com> References: <1472896767-18352-1-git-send-email-sean.wang@mediatek.com> MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160903_025958_837120_3177E623 X-CRM114-Status: GOOD ( 10.50 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: nbd@openwrt.org, keyhaede@gmail.com, netdev@vger.kernel.org, Sean Wang , linux-mediatek@lists.infradead.org, objelf@gmail.com Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+patchwork-linux-mediatek=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Sean Wang The patch makes move wmb() to outside the loop that could help RX path handling more faster although that RX descriptors aren't freed for DMA to use as soon as possible, but based on my experiment and the result shows it still can reach about 943Mbpis without performance drop that is tested based on the setup with one port using Giga PHY and 256 RX descriptors for DMA to move. Signed-off-by: Sean Wang Acked-by: John Crispin --- drivers/net/ethernet/mediatek/mtk_eth_soc.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c index 431b851..a1bdb53 100644 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c @@ -890,13 +890,14 @@ release_desc: rxd->rxd2 = RX_DMA_PLEN0(ring->buf_size); ring->calc_idx = idx; - /* make sure that all changes to the dma ring are flushed before - * we continue - */ - wmb(); - mtk_w32(eth, ring->calc_idx, MTK_PRX_CRX_IDX0); + done++; } + /* make sure that all changes to the dma ring are flushed before + * we continue + */ + wmb(); + mtk_w32(eth, ring->calc_idx, MTK_PRX_CRX_IDX0); if (done < budget) mtk_w32(eth, MTK_RX_DONE_INT, MTK_PDMA_INT_STATUS);