From patchwork Fri Sep 22 11:12:45 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Marangi X-Patchwork-Id: 13395539 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E4141CD4F57 for ; Fri, 22 Sep 2023 11:13:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233512AbjIVLNP (ORCPT ); Fri, 22 Sep 2023 07:13:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33504 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229800AbjIVLNO (ORCPT ); Fri, 22 Sep 2023 07:13:14 -0400 Received: from mail-wr1-x431.google.com (mail-wr1-x431.google.com [IPv6:2a00:1450:4864:20::431]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6CEC0180; Fri, 22 Sep 2023 04:13:07 -0700 (PDT) Received: by mail-wr1-x431.google.com with SMTP id ffacd0b85a97d-31f7638be6eso1890521f8f.3; Fri, 22 Sep 2023 04:13:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1695381186; x=1695985986; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=Mo60L/CqsBXTZMp9OSNBO8agQpgsikCTWPBLj8xU0z8=; b=iYIerVfY1NbBVwujHou3raRdNzAq/EF0Qk2tI0vUChm7hYMLIcfWAF7yTChKMbt/xu tGecAjAF8gDIPCM1bgDJzItbEE5gVYhkVGwH51UOo7HsgntvJKsbNIKwmIuKUIL0vU3S dTru+vzXt5DoHzxDZGIjkpPiofTOc+n+W9U3m9XWvb5oFFc3ZW84uskbwnP8RYnEP+/c s5mFOyC3Wy7PZguQUg+WRixmBShv0+jQc/F3Oic2ZDnNCq7MfNRCV05OpKg7SnApAA/b GQIjcc+Yc0PWThaAiWl5SifhxBBgwhXk2wA/g4xMNCMHOTcZTT9t4EApNcxX40Am0yzW olOg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695381186; x=1695985986; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=Mo60L/CqsBXTZMp9OSNBO8agQpgsikCTWPBLj8xU0z8=; b=ntKLU+7hRv+7pCDyEnjlTpVnnJC42DN+6XLjuXJSzGE9r/vGMxn0JEAsPcXhZDkmPW h4qdZvql9YyXofpq/AhKfxsedcBObDFeFKVf49jo3XHHweFyXZRDEr68RUFBOUi19dPJ 91Y2od2rIYEvMzJIrOm5b+QdnQFgKnnmE030dceZK+2ZaPPUfJQoHlIQqLnq/Gx6kmBc 1fGWGKp5A0lXFU6UhKuausSOI27O919xRNOO+bKjDqz3vK53rYWRaFfmQ6qaeQpmiijI JrOZ2brA0rpjjmHPrJrFibRKiRQawKPWsR8AJei1r5oBfXf1bykgE1RLCuIRiIpVM8UW OeFw== X-Gm-Message-State: AOJu0YzleksLRo03lHq3nQN6pm60xD2kmiwpNvTnuVafcPYniqe0T9y/ GSn+94I1DiSrrQHAbaqEtJw= X-Google-Smtp-Source: AGHT+IH7mPXmlPp61fOS1UbXVt881rz7wfseEorF4MkXdznkIZPNZgazS5rBLuHv+qOU+uGgsaXdlQ== X-Received: by 2002:a5d:694d:0:b0:314:12c:4322 with SMTP id r13-20020a5d694d000000b00314012c4322mr7281735wrw.4.1695381185667; Fri, 22 Sep 2023 04:13:05 -0700 (PDT) Received: from localhost.localdomain (93-34-89-13.ip49.fastwebnet.it. [93.34.89.13]) by smtp.googlemail.com with ESMTPSA id g10-20020adffc8a000000b003176c6e87b1sm4191765wrr.81.2023.09.22.04.13.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 22 Sep 2023 04:13:04 -0700 (PDT) From: Christian Marangi To: Vincent Whitchurch , Raju Rangoju , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexandre Torgue , Jose Abreu , Maxime Coquelin , Ping-Ke Shih , Kalle Valo , Simon Horman , Daniel Borkmann , Jiri Pirko , Hangbin Liu , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-wireless@vger.kernel.org Cc: Christian Marangi Subject: [net-next PATCH 1/3] net: introduce napi_is_scheduled helper Date: Fri, 22 Sep 2023 13:12:45 +0200 Message-Id: <20230922111247.497-1-ansuelsmth@gmail.com> X-Mailer: git-send-email 2.40.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org We currently have napi_if_scheduled_mark_missed that can be used to check if napi is scheduled but that does more thing than simply checking it and return a bool. Some driver already implement custom function to check if napi is scheduled. Drop these custom function and introduce napi_is_scheduled that simply check if napi is scheduled atomically. Update any driver and code that implement a similar check and instead use this new helper. Signed-off-by: Christian Marangi Reviewed-by: Amritha Nambiar --- drivers/net/ethernet/chelsio/cxgb3/sge.c | 8 -------- drivers/net/wireless/realtek/rtw89/core.c | 2 +- include/linux/netdevice.h | 5 +++++ net/core/dev.c | 2 +- 4 files changed, 7 insertions(+), 10 deletions(-) diff --git a/drivers/net/ethernet/chelsio/cxgb3/sge.c b/drivers/net/ethernet/chelsio/cxgb3/sge.c index 2e9a74fe0970..71fa2dc19034 100644 --- a/drivers/net/ethernet/chelsio/cxgb3/sge.c +++ b/drivers/net/ethernet/chelsio/cxgb3/sge.c @@ -2501,14 +2501,6 @@ static int napi_rx_handler(struct napi_struct *napi, int budget) return work_done; } -/* - * Returns true if the device is already scheduled for polling. - */ -static inline int napi_is_scheduled(struct napi_struct *napi) -{ - return test_bit(NAPI_STATE_SCHED, &napi->state); -} - /** * process_pure_responses - process pure responses from a response queue * @adap: the adapter diff --git a/drivers/net/wireless/realtek/rtw89/core.c b/drivers/net/wireless/realtek/rtw89/core.c index 133bf289bacb..bbf4ea3639d4 100644 --- a/drivers/net/wireless/realtek/rtw89/core.c +++ b/drivers/net/wireless/realtek/rtw89/core.c @@ -1744,7 +1744,7 @@ static void rtw89_core_rx_to_mac80211(struct rtw89_dev *rtwdev, struct napi_struct *napi = &rtwdev->napi; /* In low power mode, napi isn't scheduled. Receive it to netif. */ - if (unlikely(!test_bit(NAPI_STATE_SCHED, &napi->state))) + if (unlikely(!napi_is_scheduled(napi))) napi = NULL; rtw89_core_hw_to_sband_rate(rx_status); diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index db3d8429d50d..8eac00cd3b92 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -482,6 +482,11 @@ static inline bool napi_prefer_busy_poll(struct napi_struct *n) return test_bit(NAPI_STATE_PREFER_BUSY_POLL, &n->state); } +static inline bool napi_is_scheduled(struct napi_struct *n) +{ + return test_bit(NAPI_STATE_SCHED, &n->state); +} + bool napi_schedule_prep(struct napi_struct *n); /** diff --git a/net/core/dev.c b/net/core/dev.c index cc03a5758d2d..32ba8002f65a 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -6523,7 +6523,7 @@ static int __napi_poll(struct napi_struct *n, bool *repoll) * accidentally calling ->poll() when NAPI is not scheduled. */ work = 0; - if (test_bit(NAPI_STATE_SCHED, &n->state)) { + if (napi_is_scheduled(n)) { work = n->poll(n, weight); trace_napi_poll(n, work, weight); } From patchwork Fri Sep 22 11:12:46 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Marangi X-Patchwork-Id: 13395540 X-Patchwork-Delegate: johannes@sipsolutions.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5F710CD4F57 for ; Fri, 22 Sep 2023 11:13:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229800AbjIVLNS (ORCPT ); Fri, 22 Sep 2023 07:13:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33528 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233534AbjIVLNQ (ORCPT ); Fri, 22 Sep 2023 07:13:16 -0400 Received: from mail-wr1-x429.google.com (mail-wr1-x429.google.com [IPv6:2a00:1450:4864:20::429]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 05ECBAC; Fri, 22 Sep 2023 04:13:09 -0700 (PDT) Received: by mail-wr1-x429.google.com with SMTP id ffacd0b85a97d-32008e339adso1915373f8f.2; Fri, 22 Sep 2023 04:13:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1695381187; x=1695985987; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=NO4PPCAYeBqa8N3X8iNMzO62NO9a8Aa1IWA9xi7rYvw=; b=OV0En4bJL0YZ9Vp4bzv/PvNMsEz5F9WxMBaUzyBzhNNpp62+MqMt684g8kW81ZGZKA azKi8tcCSX2i4SwMB2rG2Vfr5aimCHUxcLYVv1g8eo9/0dS1srIGE50Iu7t18sxsZXGk eW7D6FeelZdrp1MCwLyyBIKO7SSDpwcqqvDam/tNaXopIS8RyGgbpKrLBZTlutBFnFdz RIwJEu6eplVVx0PFksuyzXxlLgORiPzzt0t0iStny2PqunUjf22ifKNLotELSgSRO1Ku mPMUYw5s36N4gokqZRanW43Af2iPrViAVDRxthkF4doSHTcE9+RKEcEhU+2jjmN5eSFX tFww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695381187; x=1695985987; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=NO4PPCAYeBqa8N3X8iNMzO62NO9a8Aa1IWA9xi7rYvw=; b=aDKKNl0RynPHarW9YblpbdDiMOW/gKWAAlX2Cbzvel7x56+YjQkJ6nZUFX+ykf8x85 C682hbffyp2c+9coDmVkMLczl2FgZ5ma67ggBnKoGb5vLt5XdA95yYV0wKjLbNRiq/Oq 37fLrfjalaUarGX8WP0CcVf7i+x0tperMsnVg4QNpxsF95bD33aOUufI31Go9oVV5T1e EUhGpwCi2zQg0ePkCe0uIubJjw5Hx2XJ7mrHAiDLWQyTKzSgfAu8BxgIHdI7amdl9nLP Ok5RFzklGx5ZiROPDqnXW9P1PdkqfgPZB1tWM0vl/JRrUyeTT5fUsHIdCu+JRcXAiTVv HF4w== X-Gm-Message-State: AOJu0Yye60J+b6zoP+okvSua/ut0hiWV+8PKam4c0SMmlpdBmKONbzYy ti8lyb9X7cAi2M+0Eo0Y7qQ= X-Google-Smtp-Source: AGHT+IGt2zxWyI/cHaEIM9YNy0bqvfBVCcm7j3twnx0VeOiWaEz6/6Yr9n/oPYq1bGBQ0w34CKjfgA== X-Received: by 2002:adf:fbcf:0:b0:31f:d8b3:e9f5 with SMTP id d15-20020adffbcf000000b0031fd8b3e9f5mr6831681wrs.34.1695381186972; Fri, 22 Sep 2023 04:13:06 -0700 (PDT) Received: from localhost.localdomain (93-34-89-13.ip49.fastwebnet.it. [93.34.89.13]) by smtp.googlemail.com with ESMTPSA id g10-20020adffc8a000000b003176c6e87b1sm4191765wrr.81.2023.09.22.04.13.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 22 Sep 2023 04:13:06 -0700 (PDT) From: Christian Marangi To: Vincent Whitchurch , Raju Rangoju , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexandre Torgue , Jose Abreu , Maxime Coquelin , Ping-Ke Shih , Kalle Valo , Simon Horman , Daniel Borkmann , Jiri Pirko , Hangbin Liu , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-wireless@vger.kernel.org Cc: Christian Marangi Subject: [net-next PATCH 2/3] net: stmmac: improve TX timer arm logic Date: Fri, 22 Sep 2023 13:12:46 +0200 Message-Id: <20230922111247.497-2-ansuelsmth@gmail.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230922111247.497-1-ansuelsmth@gmail.com> References: <20230922111247.497-1-ansuelsmth@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org There is currently a problem with the TX timer getting armed multiple unnecessary times causing big performance regression on some device that suffer from heavy handling of hrtimer rearm. The use of the TX timer is an old implementation that predates the napi implementation and the interrupt enable/disable handling. Due to stmmac being a very old code, the TX timer was never evaluated again with this new implementation and was kept there causing performance regression. The performance regression started to appear with kernel version 4.19 with 8fce33317023 ("net: stmmac: Rework coalesce timer and fix multi-queue races") where the timer was reduced to 1ms causing it to be armed 40 times more than before. Decreasing the timer made the problem more present and caused the regression in the other of 600-700mbps on some device (regression where this was notice is ipq806x). The problem is in the fact that handling the hrtimer on some target is expensive and recent kernel made the timer armed much more times. A solution that was proposed was reverting the hrtimer change and use mod_timer but such solution would still hide the real problem in the current implementation. To fix the regression, apply some additional logic and skip arming the timer when not needed. Arm the timer ONLY if a napi is not already scheduled. Running the timer is redundant since the same function (stmmac_tx_clean) will run in the napi TX poll. Also try to cancel any timer if a napi is scheduled to prevent redundant run of TX call. With the following new logic the original performance are restored while keeping using the hrtimer. Signed-off-by: Christian Marangi --- .../net/ethernet/stmicro/stmmac/stmmac_main.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 9201ed778ebc..14bf6fae6662 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -2994,13 +2994,25 @@ static void stmmac_tx_timer_arm(struct stmmac_priv *priv, u32 queue) { struct stmmac_tx_queue *tx_q = &priv->dma_conf.tx_queue[queue]; u32 tx_coal_timer = priv->tx_coal_timer[queue]; + struct stmmac_channel *ch; + struct napi_struct *napi; if (!tx_coal_timer) return; - hrtimer_start(&tx_q->txtimer, - STMMAC_COAL_TIMER(tx_coal_timer), - HRTIMER_MODE_REL); + ch = &priv->channel[tx_q->queue_index]; + napi = tx_q->xsk_pool ? &ch->rxtx_napi : &ch->tx_napi; + + /* Arm timer only if napi is not already scheduled. + * Try to cancel any timer if napi is scheduled, timer will be armed + * again in the next scheduled napi. + */ + if (unlikely(!napi_is_scheduled(napi))) + hrtimer_start(&tx_q->txtimer, + STMMAC_COAL_TIMER(tx_coal_timer), + HRTIMER_MODE_REL); + else + hrtimer_try_to_cancel(&tx_q->txtimer); } /** From patchwork Fri Sep 22 11:12:47 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Marangi X-Patchwork-Id: 13395541 X-Patchwork-Delegate: johannes@sipsolutions.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id ECE97CD4F57 for ; Fri, 22 Sep 2023 11:13:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233539AbjIVLNV (ORCPT ); Fri, 22 Sep 2023 07:13:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33592 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233540AbjIVLNR (ORCPT ); Fri, 22 Sep 2023 07:13:17 -0400 Received: from mail-wm1-x32a.google.com (mail-wm1-x32a.google.com [IPv6:2a00:1450:4864:20::32a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 82A6D114; Fri, 22 Sep 2023 04:13:10 -0700 (PDT) Received: by mail-wm1-x32a.google.com with SMTP id 5b1f17b1804b1-4053db20d03so6060525e9.2; Fri, 22 Sep 2023 04:13:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1695381189; x=1695985989; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=/ijlwZ6JRdK1U0SnHerxGcEJGjK9VRf4PRp/VeOrzMQ=; b=Ui54MJAW4B/VxxzITX2OiWb98Jy5pJ7NHhxjB+lfMtvygA44FuyaWuBSmeiVF77qR+ P8GX72ChlT8RsA454fmSjj9RH6PMLFVmRyYhWt3xKCpAFP/hrK06HigE1MnOQSyfaU9t ws9sQKJuegRYhQacMuFu9YMCfGtJGeQR68VO5X3tpiJmXljCJjxjftbhSmQ0/l5TDLeU yA5S54fyVyDpFWi7nveLTxOo0GrJ+l/dcuWBKHx+2D42Rp+5sibILDLV9Kcz1UoU2CPN DkCtMUhx9p1x11JFcx22kUOY1f8oUXTceZINFfn+sujZ5CtJU05vUIP4gZuSWVUfxDRC syqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695381189; x=1695985989; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=/ijlwZ6JRdK1U0SnHerxGcEJGjK9VRf4PRp/VeOrzMQ=; b=ITlib30bkGKJfD9QCXCBPzA5k1zJpX0bBIgokw/NyT9DL6aeaY6Usoxr2uRfIoS2nC Bq26EMby0mlVHIJtzw6SbUF3LqdIdbvInJ0QbqPxqWxvlM/5yOZA5ydNpcy8F9LABOId +AkfmGwdjs/k9TCRPPxlqHrHs7fCr77PHfUqRAQeCS8p4chPahhWxl/n98cXFy+mkxA/ astVIYobGCISOjkpekowgftVMD03EWPyh7gUWOaOEd4NOS4fQDAyd9fglUcsgwOVFz5T 8nJTTye30tphF8VrqIIJgXf05ojh2551iO4I3urZhw5SUsX6Iz4ED8uQWVhWqgZAwANU JCkQ== X-Gm-Message-State: AOJu0YymSZd3YVRkHwbCOraqFR4unpzJwNpp24GjwRTPMxMAzIf3ZuUJ +MgINd11X7CtYrlKnT5RKAw= X-Google-Smtp-Source: AGHT+IHTzusDD1Vj12nFTAofcTh5ujgUoGMSUjxYvnBVt5FrCDDmYAOQS2TIjfWAp8W6AwxsKaiBCA== X-Received: by 2002:a05:600c:152:b0:403:cc64:2dbf with SMTP id w18-20020a05600c015200b00403cc642dbfmr7548257wmm.27.1695381188563; Fri, 22 Sep 2023 04:13:08 -0700 (PDT) Received: from localhost.localdomain (93-34-89-13.ip49.fastwebnet.it. [93.34.89.13]) by smtp.googlemail.com with ESMTPSA id g10-20020adffc8a000000b003176c6e87b1sm4191765wrr.81.2023.09.22.04.13.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 22 Sep 2023 04:13:07 -0700 (PDT) From: Christian Marangi To: Vincent Whitchurch , Raju Rangoju , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexandre Torgue , Jose Abreu , Maxime Coquelin , Ping-Ke Shih , Kalle Valo , Simon Horman , Daniel Borkmann , Jiri Pirko , Hangbin Liu , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-wireless@vger.kernel.org Cc: Christian Marangi Subject: [net-next PATCH 3/3] net: stmmac: increase TX coalesce timer to 5ms Date: Fri, 22 Sep 2023 13:12:47 +0200 Message-Id: <20230922111247.497-3-ansuelsmth@gmail.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230922111247.497-1-ansuelsmth@gmail.com> References: <20230922111247.497-1-ansuelsmth@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Commit 8fce33317023 ("net: stmmac: Rework coalesce timer and fix multi-queue races") decreased the TX coalesce timer from 40ms to 1ms. This caused some performance regression on some target (regression was reported at least on ipq806x) in the order of 600mbps dropping from gigabit handling to only 200mbps. The problem was identified in the TX timer getting armed too much time. While this was fixed and improved in another commit, performance can be improved even further by increasing the timer delay a bit moving from 1ms to 5ms. The value is a good balance between battery saving by prevending too much interrupt to be generated and permitting good performance for internet oriented devices. Signed-off-by: Christian Marangi --- drivers/net/ethernet/stmicro/stmmac/common.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/common.h b/drivers/net/ethernet/stmicro/stmmac/common.h index 403cb397d4d3..2d9f895c2193 100644 --- a/drivers/net/ethernet/stmicro/stmmac/common.h +++ b/drivers/net/ethernet/stmicro/stmmac/common.h @@ -290,7 +290,7 @@ struct stmmac_safety_stats { #define MIN_DMA_RIWT 0x10 #define DEF_DMA_RIWT 0xa0 /* Tx coalesce parameters */ -#define STMMAC_COAL_TX_TIMER 1000 +#define STMMAC_COAL_TX_TIMER 5000 #define STMMAC_MAX_COAL_TX_TICK 100000 #define STMMAC_TX_MAX_FRAMES 256 #define STMMAC_TX_FRAMES 25