From patchwork Thu Aug 19 05:45:40 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kai-Heng Feng X-Patchwork-Id: 12446273 X-Patchwork-Delegate: kuba@kernel.org 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 673EDC432BE for ; Thu, 19 Aug 2021 05:46:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4919B60ED3 for ; Thu, 19 Aug 2021 05:46:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230168AbhHSFqq (ORCPT ); Thu, 19 Aug 2021 01:46:46 -0400 Received: from smtp-relay-canonical-0.canonical.com ([185.125.188.120]:39412 "EHLO smtp-relay-canonical-0.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229998AbhHSFqp (ORCPT ); Thu, 19 Aug 2021 01:46:45 -0400 Received: from localhost.localdomain (1-171-223-154.dynamic-ip.hinet.net [1.171.223.154]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp-relay-canonical-0.canonical.com (Postfix) with ESMTPSA id D6965411BC; Thu, 19 Aug 2021 05:46:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canonical.com; s=20210705; t=1629351966; bh=QdizpEE7M+xdJvzFRIpo7bvWSKswgDq1vyuyBjROpYk=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=kccgw9IjTLcQdwGb8aPTcxHwRXd0AmcjjoEcnlgfXD+snpgt56AFgAgI+Ckz7t2BN 2cNOxT63UDqrRvRef3AcgtoH0rNpYduGRoP38DLxXzwic7mewWI/9guJCLlYR1RF+d JoSVRc0of99h4Sdm28ckaCzgaHDSK9VBcmmDolXynokwcIQjwcfw0dIgRo5iXLHUFZ 09XcVtroVm3XmI7LcNOGtpvrvBQb/LMgoea4G9Y0x6JJ60VMgTquLEvH8AQFlICXUE t8FByD3j4KXlx80QM9eaYLjm3JY21Wf3IZWajFtpm0ReC7u3gqGrljzxWzkNunmyV+ uj6xpIaQ1qp+w== From: Kai-Heng Feng To: hkallweit1@gmail.com, nic_swsd@realtek.com, bhelgaas@google.com Cc: davem@davemloft.net, kuba@kernel.org, netdev@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Kai-Heng Feng Subject: [PATCH net-next v3 1/3] r8169: Implement dynamic ASPM mechanism Date: Thu, 19 Aug 2021 13:45:40 +0800 Message-Id: <20210819054542.608745-2-kai.heng.feng@canonical.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210819054542.608745-1-kai.heng.feng@canonical.com> References: <20210819054542.608745-1-kai.heng.feng@canonical.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org r8169 NICs on some platforms have abysmal speed when ASPM is enabled. Same issue can be observed with older vendor drivers. The issue is however solved by the latest vendor driver. There's a new mechanism, which disables r8169's internal ASPM when the NIC traffic has more than 10 packets, and vice versa. The possible reason for this is likely because the buffer on the chip is too small for its ASPM exit latency. Realtek confirmed that all their PCIe LAN NICs, r8106, r8168 and r8125 use dynamic ASPM under Windows. So implement the same mechanism here to resolve the issue. Signed-off-by: Kai-Heng Feng --- v3: - Use msecs_to_jiffies() for delay time - Use atomic_t instead of mutex for bh - Mention the buffer size and ASPM exit latency in commit message v2: - Use delayed_work instead of timer_list to avoid interrupt context - Use mutex to serialize packet counter read/write - Wording change drivers/net/ethernet/realtek/r8169_main.c | 44 ++++++++++++++++++++++- 1 file changed, 43 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c index 7a69b468584a2..3359509c1c351 100644 --- a/drivers/net/ethernet/realtek/r8169_main.c +++ b/drivers/net/ethernet/realtek/r8169_main.c @@ -624,6 +624,10 @@ struct rtl8169_private { unsigned supports_gmii:1; unsigned aspm_manageable:1; + unsigned rtl_aspm_enabled:1; + struct delayed_work aspm_toggle; + atomic_t aspm_packet_count; + dma_addr_t counters_phys_addr; struct rtl8169_counters *counters; struct rtl8169_tc_offsets tc_offset; @@ -2665,8 +2669,13 @@ static void rtl_pcie_state_l2l3_disable(struct rtl8169_private *tp) static void rtl_hw_aspm_clkreq_enable(struct rtl8169_private *tp, bool enable) { + if (!tp->aspm_manageable && enable) + return; + + tp->rtl_aspm_enabled = enable; + /* Don't enable ASPM in the chip if OS can't control ASPM */ - if (enable && tp->aspm_manageable) { + if (enable) { RTL_W8(tp, Config5, RTL_R8(tp, Config5) | ASPM_en); RTL_W8(tp, Config2, RTL_R8(tp, Config2) | ClkReqEn); } else { @@ -4415,6 +4424,7 @@ static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp, dirty_tx = tp->dirty_tx; + atomic_add(tp->cur_tx - dirty_tx, &tp->aspm_packet_count); while (READ_ONCE(tp->cur_tx) != dirty_tx) { unsigned int entry = dirty_tx % NUM_TX_DESC; u32 status; @@ -4559,6 +4569,8 @@ static int rtl_rx(struct net_device *dev, struct rtl8169_private *tp, int budget rtl8169_mark_to_asic(desc); } + atomic_add(count, &tp->aspm_packet_count); + return count; } @@ -4666,8 +4678,32 @@ static int r8169_phy_connect(struct rtl8169_private *tp) return 0; } +#define ASPM_PACKET_THRESHOLD 10 +#define ASPM_TOGGLE_INTERVAL 1000 + +static void rtl8169_aspm_toggle(struct work_struct *work) +{ + struct rtl8169_private *tp = container_of(work, struct rtl8169_private, + aspm_toggle.work); + int packet_count; + bool enable; + + packet_count = atomic_xchg(&tp->aspm_packet_count, 0); + enable = packet_count <= ASPM_PACKET_THRESHOLD; + + if (tp->rtl_aspm_enabled != enable) { + rtl_unlock_config_regs(tp); + rtl_hw_aspm_clkreq_enable(tp, enable); + rtl_lock_config_regs(tp); + } + + schedule_delayed_work(&tp->aspm_toggle, msecs_to_jiffies(ASPM_TOGGLE_INTERVAL)); +} + static void rtl8169_down(struct rtl8169_private *tp) { + cancel_delayed_work_sync(&tp->aspm_toggle); + /* Clear all task flags */ bitmap_zero(tp->wk.flags, RTL_FLAG_MAX); @@ -4694,6 +4730,8 @@ static void rtl8169_up(struct rtl8169_private *tp) rtl_reset_work(tp); phy_start(tp->phydev); + + schedule_delayed_work(&tp->aspm_toggle, msecs_to_jiffies(ASPM_TOGGLE_INTERVAL)); } static int rtl8169_close(struct net_device *dev) @@ -5354,6 +5392,10 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) INIT_WORK(&tp->wk.work, rtl_task); + INIT_DELAYED_WORK(&tp->aspm_toggle, rtl8169_aspm_toggle); + + atomic_set(&tp->aspm_packet_count, 0); + rtl_init_mac_address(tp); dev->ethtool_ops = &rtl8169_ethtool_ops;