From patchwork Tue Feb 16 01:08:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Sven Van Asbroeck X-Patchwork-Id: 12089295 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 68358C433E0 for ; Tue, 16 Feb 2021 01:08:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2B2A864DBA for ; Tue, 16 Feb 2021 01:08:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229853AbhBPBIz (ORCPT ); Mon, 15 Feb 2021 20:08:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49504 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229713AbhBPBIw (ORCPT ); Mon, 15 Feb 2021 20:08:52 -0500 Received: from mail-qk1-x734.google.com (mail-qk1-x734.google.com [IPv6:2607:f8b0:4864:20::734]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A6F20C061574; Mon, 15 Feb 2021 17:08:12 -0800 (PST) Received: by mail-qk1-x734.google.com with SMTP id m144so8071094qke.10; Mon, 15 Feb 2021 17:08:12 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=ZaZIFaqLAcoIpglIDw+HT+fI3iJImvmhXF5r3MbSWiw=; b=LlwATVsqlkdjR3p89OA+DRvHw8i/XF7yJACmu1f3UKODxORuHbXcOpDlFhM25N1UPL 9fAZ3gU5gtZinwjL8uxTvBWN/my6tVuDSxwSjscUn8j1Co2oTWunSgL/FBkFb/jzfc9K s50/xVJVSGq5dA8rLc41yRCXBxkLjtKlxhvDdpl5hAMHphhNchUm5bcLGjIxQHkT4PLh NzkekLTFQcZ1PSQmDrdHwz9+Rau7KdchTjgjlQEZZJzcgGhPak16Osv7jXz1umeVt/Sz cJ4bgvswIg842UgBIslU2X4bFFpSqzk3uaI8zjrETOb+xFBGikCmgvR+3AEKu3h7lfCY 94Ug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=ZaZIFaqLAcoIpglIDw+HT+fI3iJImvmhXF5r3MbSWiw=; b=ie/3FGokGf57B+/OTt8aLjCMAuk1OWCJUfRwwX9S6DA6RLfQRNhAWctDxMPOeXxey/ YlNQhglU4d12606CKiy/SzcpltgnNXmXCUbcgPxAgrV5sfgxZJ9uo82SV54u6BhI7eSn kbXXjhMW5cbn23UELbRndjTQ0ZL0sb+AUK4W15Hb76/FLD7zUYQf879hQfbvSlp6LeQ0 WmvOzOHdf+RJ+IuYLnLf+CFcnqN8T18omGNF9SZ5NseA7/haV1TCAep+T2NGWQ1B15GC lZ7CTsow9JOPr2E0pt5ikRvAMCpjp1tmUS+M1uVyN+oLE52ZGZaqxJFkkh24wO5hp85E 2EwQ== X-Gm-Message-State: AOAM533LsFh8UkF044KC6Bv5cL+ZOtnBNH2oHTn5foGPPaclIQthNMkT LxvIu7SEN741E9rzyhurqMc= X-Google-Smtp-Source: ABdhPJxexwTlBo8F5Q86h3Bq4ujhp8mfPfQAWU5+08zNfmCH6cIM+Af1LMdDkdoBgXrLwIu0X/f8DA== X-Received: by 2002:a37:bd84:: with SMTP id n126mr17333299qkf.54.1613437691461; Mon, 15 Feb 2021 17:08:11 -0800 (PST) Received: from localhost.localdomain ([198.52.185.246]) by smtp.gmail.com with ESMTPSA id b20sm508830qto.45.2021.02.15.17.08.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 Feb 2021 17:08:11 -0800 (PST) From: Sven Van Asbroeck X-Google-Original-From: Sven Van Asbroeck To: Bryan Whitehead , UNGLinuxDriver@microchip.com, David S Miller , Jakub Kicinski Cc: Sven Van Asbroeck , Andrew Lunn , Alexey Denisov , Sergej Bauer , Tim Harvey , =?utf-8?q?Anders_R=C3=B8nningen?= , Hillf Danton , Christoph Hellwig , Willem de Bruijn , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH net-next v3 0/5] lan743x speed boost Date: Mon, 15 Feb 2021 20:08:01 -0500 Message-Id: <20210216010806.31948-1-TheSven73@gmail.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Sven Van Asbroeck Tree: git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git # 9ec5eea5b6ac v2 -> v3: - Bryan Whitehead: + add Bryan's reviewed-by tag to patch 1/5. + Only use FRAME_LENGTH if the LS bit is checked. If set use the smaller of FRAME_LENGTH or buffer length. If clear use buffer length. + Correct typo in cover letter history (swap "packet" <-> "buffer"). v1 -> v2: - Andrew Lunn: + always keep to Reverse Christmas Tree. + "changing the cache operations to operate on the received length" should go in its own, separate patch, so it can be easily backed out if "interesting things" should happen with it. - Bryan Whitehead: + multi-buffer patch concept "looks good". As a result, I will squash the intermediate "dma buffer only" patch which demonstrated the speed boost using an inflexible solution (w/o multi-buffers). + Rename lan743x_rx_process_packet() to lan743x_rx_process_buffer() + Remove unused RX_PROCESS_RESULT_PACKET_DROPPED + Rename RX_PROCESS_RESULT_PACKET_RECEIVED to RX_PROCESS_RESULT_BUFFER_RECEIVED + Fold "unmap from dma" into lan743x_rx_init_ring_element() to prevent use-after-dma-unmap issue + ensure that skb allocation issues do not result in the driver sending incomplete packets to the OS. E.g. a three-buffer packet, with the middle buffer missing - Willem De Bruyn: skb_hwtstamps(skb) always returns a non-null value, if the skb parameter points to a valid skb. Summary of my tests below. Suggestions for better tests are very welcome. Tests with debug logging enabled (add #define DEBUG). 1. Limit rx buffer size to 500, so mtu (1500) takes 3 buffers. Ping to chip, verify correct packet size is sent to OS. Ping large packets to chip (ping -s 1400), verify correct packet size is sent to OS. Ping using packets around the buffer size, verify number of buffers is changing, verify correct packet size is sent to OS: $ ping -s 472 $ ping -s 473 $ ping -s 992 $ ping -s 993 Verify that each packet is followed by extension processing. 2. Limit rx buffer size to 500, so mtu (1500) takes 3 buffers. Run iperf3 -s on chip, verify that packets come in 3 buffers at a time. Verify that packet size is equal to mtu. Verify that each packet is followed by extension processing. 3. Set mtu to 2000 on chip and host. Limit rx buffer size to 500, so mtu (2000) takes 4 buffers. Run iperf3 -s on chip, verify that packets come in 4 buffers at a time. Verify that packet size is equal to mtu. Verify that each packet is followed by extension processing. Tests with debug logging DISabled (remove #define DEBUG). 4. Limit rx buffer size to 500, so mtu (1500) takes 3 buffers. Run iperf3 -s on chip, note sustained rx speed. Set mtu to 2000, so mtu takes 4 buffers. Run iperf3 -s on chip, note sustained rx speed. Verify no packets are dropped in both cases. Verify speeds are roughly comparable. Tests with DEBUG_KMEMLEAK on: $ mount -t debugfs nodev /sys/kernel/debug/ $ echo scan > /sys/kernel/debug/kmemleak 5. Limit rx buffer size to 500, so mtu (1500) takes 3 buffers. Run the following tests concurrently for at least one hour: - iperf3 -s on chip - ping -> chip Monitor reported memory leaks. 6. Set mtu to 2000. Limit rx buffer size to 500, so mtu (2000) takes 4 buffers. Run the following tests concurrently for at least one hour: - iperf3 -s on chip - ping -> chip Monitor reported memory leaks. 7. Simulate low-memory in lan743x_rx_allocate_skb(): fail once every 100 allocations. Repeat (5) and (6). Monitor reported memory leaks. 8. Simulate low-memory in lan743x_rx_allocate_skb(): fail 10 allocations in a row in every 100. Repeat (5) and (6). Monitor reported memory leaks. 9. Simulate low-memory in lan743x_rx_trim_skb(): fail 1 allocation in every 100. Repeat (5) and (6). Monitor reported memory leaks. Tests with debug logging enabled (add #define DEBUG). 10. Set the chip mtu to 1500, generate lots of network traffic. Stop all network traffic. Set the chip and remote mtus to 8000. Ping remote -> chip: $ ping -s 7000 Verify that the first few received packets are multi-buffer. Verify no pings are dropped. Tests with DEBUG_KMEMLEAK on: $ mount -t debugfs nodev /sys/kernel/debug/ $ echo scan > /sys/kernel/debug/kmemleak 11. Start with chip mtu at 1500, host mtu at 8000. Run concurrently: - iperf3 -s on chip - ping -> chip Cycle the chip mtu between 1500 and 8000 every 10 seconds. Scan kmemleak periodically to watch for memory leaks. Verify that the mtu changeover happens smoothly, i.e. the iperf3 test does not report periods where speed drops and recovers suddenly. Note: iperf3 occasionally reports dropped packets on changeover. This behaviour also occurs on the original driver, it's not a regression. Possibly related to the chip's mac rx being disabled when the mtu is changed. To: Bryan Whitehead To: UNGLinuxDriver@microchip.com To: "David S. Miller" To: Jakub Kicinski Cc: Andrew Lunn Cc: Alexey Denisov Cc: Sergej Bauer Cc: Tim Harvey Cc: Anders Rønningen Cc: Hillf Danton Cc: Christoph Hellwig Cc: Willem de Bruijn Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Sven Van Asbroeck (5): lan743x: boost performance on cpu archs w/o dma cache snooping lan743x: sync only the received area of an rx ring buffer TEST ONLY: lan743x: limit rx ring buffer size to 500 bytes TEST ONLY: lan743x: skb_alloc failure test TEST ONLY: lan743x: skb_trim failure test drivers/net/ethernet/microchip/lan743x_main.c | 352 +++++++++--------- drivers/net/ethernet/microchip/lan743x_main.h | 5 +- 2 files changed, 174 insertions(+), 183 deletions(-) Tested-by: UNGLinuxDriver@microchip.com