From mboxrd@z Thu Jan 1 00:00:00 1970 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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 E5840C433B4 for ; Thu, 22 Apr 2021 04:10:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BFD64613FB for ; Thu, 22 Apr 2021 04:10:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235159AbhDVELX (ORCPT ); Thu, 22 Apr 2021 00:11:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40746 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234679AbhDVEKV (ORCPT ); Thu, 22 Apr 2021 00:10:21 -0400 Received: from mail-pf1-x42e.google.com (mail-pf1-x42e.google.com [IPv6:2607:f8b0:4864:20::42e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 77881C06174A; Wed, 21 Apr 2021 21:09:47 -0700 (PDT) Received: by mail-pf1-x42e.google.com with SMTP id a12so30780617pfc.7; Wed, 21 Apr 2021 21:09:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=4KIdtN06FgF/t+etJxyiKFbFDdfz1IAmwoqjnTRUY1Q=; b=ekE6yKJ21GS2BTKeAlc+gBcCC1y9VzR7QBm1Rwve24KFcJ+0jNVnyEwmOwJl0lc/ho HyceoJIh+MUMTQjmMu4LScm0ubkQ0jjL01eKuoW4G65UuUYJ1l8W/0POGR2Deva/KspM G3jSY2RBu6FnW+ZPTIBOWgWnL7o7oHdYT5xTeTDJfQXG0rvU9U+Idr4pObH7IGrVtfe8 7Dv9p0Z0i2BNeI382eLt+dvGT49vhsadMXHj7k4uzcHgaLigpt65RnT7/x/sucLZaoRD hlWse+uINeiHf2fiDhFmH0kqG+jmLHxbt57wz1a+kX923t/lX3ZHkr106Egkia+d9Wrj Du0A== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=4KIdtN06FgF/t+etJxyiKFbFDdfz1IAmwoqjnTRUY1Q=; b=VuXGE0OF63DgvxWSEH2Cfgc6DGKMpuObiQ5keXbJQP5nM9nPxYmQom89hP5H2LQ6tN EscH+wtVqEOJcJ8Tk++T7fM59qt0HTl0yAD9OhfsMDp2hukx//DTBMRcfwVyUUOHsyZH EHG+6ao99K4A3VI1jmGRYEQXGMIP3V+ERpciPqx5mJMI5H41DhIWYK8Q3oG2BXp1ERKD SpMtd0zi32kaXyk7BbJrRzLRtntlXyUg5wq75/j3szKRQ3rSNRMXu7VcXGSz4jAYZzWv Z5OLLQY6r5QglA3O4xcNxZzc5zTOexNOsfGY7t+a3LXkwyiDwpzpmtRaESCsiZJ6zm/R b70A== X-Gm-Message-State: AOAM5314XO9NRz0Smv1TAI0UeuTpmUZlqe6xMIj5qShurOhPYlwntjjC q5BQBZKYA76DER4UaBpN0T8= X-Google-Smtp-Source: ABdhPJxj4FOHEJL6eLG9j3s9bhz2cI5WstGPCENCBwwWnpKmfpEhlE8pRtJ7/rs9B268HliKtl5R2w== X-Received: by 2002:a63:4f21:: with SMTP id d33mr1525579pgb.434.1619064587028; Wed, 21 Apr 2021 21:09:47 -0700 (PDT) Received: from z640-arch.lan ([2602:61:7344:f100::678]) by smtp.gmail.com with ESMTPSA id i17sm635354pfd.84.2021.04.21.21.09.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 21 Apr 2021 21:09:46 -0700 (PDT) From: Ilya Lipnitskiy To: Felix Fietkau , John Crispin , Sean Wang , Mark Lee , "David S. Miller" , Jakub Kicinski , Matthias Brugger , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org Cc: Ilya Lipnitskiy Subject: [PATCH net-next 11/14] net: ethernet: mtk_eth_soc: only read the full RX descriptor if DMA is done Date: Wed, 21 Apr 2021 21:09:11 -0700 Message-Id: <20210422040914.47788-12-ilya.lipnitskiy@gmail.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210422040914.47788-1-ilya.lipnitskiy@gmail.com> References: <20210422040914.47788-1-ilya.lipnitskiy@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Felix Fietkau Uncached memory access is expensive, and there is no need to access all descriptor words if we can't process them anyway Signed-off-by: Felix Fietkau Signed-off-by: Ilya Lipnitskiy --- drivers/net/ethernet/mediatek/mtk_eth_soc.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c index 01ad10c76d53..5a531bb83348 100644 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c @@ -775,13 +775,18 @@ static inline int mtk_max_buf_size(int frag_size) return buf_size; } -static inline void mtk_rx_get_desc(struct mtk_rx_dma *rxd, +static inline bool mtk_rx_get_desc(struct mtk_rx_dma *rxd, struct mtk_rx_dma *dma_rxd) { - rxd->rxd1 = READ_ONCE(dma_rxd->rxd1); rxd->rxd2 = READ_ONCE(dma_rxd->rxd2); + if (!(rxd->rxd2 & RX_DMA_DONE)) + return false; + + rxd->rxd1 = READ_ONCE(dma_rxd->rxd1); rxd->rxd3 = READ_ONCE(dma_rxd->rxd3); rxd->rxd4 = READ_ONCE(dma_rxd->rxd4); + + return true; } /* the qdma core needs scratch memory to be setup */ @@ -1253,8 +1258,7 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget, rxd = &ring->dma[idx]; data = ring->data[idx]; - mtk_rx_get_desc(&trxd, rxd); - if (!(trxd.rxd2 & RX_DMA_DONE)) + if (!mtk_rx_get_desc(&trxd, rxd)) break; /* find out which mac the packet come from. values start at 1 */ -- 2.31.1