From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933598AbdBQKHl (ORCPT ); Fri, 17 Feb 2017 05:07:41 -0500 Received: from mx0b-0016f401.pphosted.com ([67.231.156.173]:50725 "EHLO mx0b-0016f401.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755596AbdBQKHi (ORCPT ); Fri, 17 Feb 2017 05:07:38 -0500 From: Jisheng Zhang To: , , CC: , , , Jisheng Zhang Subject: [PATCH net-next v2 0/2] net: mvneta: improve rx performance Date: Fri, 17 Feb 2017 18:02:31 +0800 Message-ID: <20170217100233.2325-1-jszhang@marvell.com> X-Mailer: git-send-email 2.11.0 MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-02-17_08:,, signatures=0 X-Proofpoint-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1612050000 definitions=main-1702170096 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In hot code path such as mvneta_rx_hwbm() and mvneta_rx_swbm(), we may access fields of rx_desc. The rx_desc is allocated by dma_alloc_coherent, it's uncacheable if the device isn't cache coherent, reading from uncached memory is fairly slow. patch1 reuses the read out status to getting status field of rx_desc again. patch2 uses cacheable memory to store the rx buffer DMA address. We get the following performance data on Marvell BG4CT Platforms (tested with iperf): before the patch: recving 1GB in mvneta_rx_swbm() costs 149265960 ns after the patch: recving 1GB in mvneta_rx_swbm() costs 1421565640 ns We saved 4.76% time. RFC: can we do similar modification for tx? If yes, I can prepare a v2. Basically, these two patches do what Arnd mentioned in [1]. Hi Arnd, I added "Suggested-by you" tag, I hope you don't mind ;) Thanks [1] https://www.spinics.net/lists/netdev/msg405889.html Since v1: - correct the performance data typo Jisheng Zhang (2): net: mvneta: avoid getting status from rx_desc as much as possible net: mvneta: Use cacheable memory to store the rx buffer DMA address drivers/net/ethernet/marvell/mvneta.c | 36 ++++++++++++++++++++--------------- 1 file changed, 21 insertions(+), 15 deletions(-) -- 2.11.0