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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1FA3AC3DA5D for ; Mon, 22 Jul 2024 16:18:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ac4TBOhO4Lvkf/O2AokVMuwcwMPMmOE7Ro7pJm1rvQk=; b=Bye/qO+UoAVa2rIftwo/mBTBeP r9XrBI+rEJoVxcZVJ97OlN1wdmDupsFDQaWrfBAiTXaf4EITfG4BqBO2z5kTgsUrwp1SLToCAEZva T49oLldg8VdL1aTW/5CUnJ9x3qay7EC0or75CRHdSSeqVRuBlo3nrVNtPfclahx5oJtc1bA5otQpZ 22a5V+G7lQ/Ql4/WFr8hFHpv6RsiHbKdeppmDIDsov8SUT3ZqfHCBZE4h/LSh5xk+1DaUReJNat+X isted1/QoacT6NqbDHS6ouH8H8VARYSyPZMzTEC0RIxo2Ee7f9oyW9jnx700pVTFAE551NZgmAxJF E3XxyjjA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sVvjc-0000000A3fw-2HrK; Mon, 22 Jul 2024 16:18:00 +0000 Received: from mail-pl1-x62d.google.com ([2607:f8b0:4864:20::62d]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sVvjE-0000000A3Xv-11vp for linux-mediatek@lists.infradead.org; Mon, 22 Jul 2024 16:17:38 +0000 Received: by mail-pl1-x62d.google.com with SMTP id d9443c01a7336-1fd65aaac27so18012055ad.1 for ; Mon, 22 Jul 2024 09:17:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fastly.com; s=google; t=1721665055; x=1722269855; darn=lists.infradead.org; h=in-reply-to:content-disposition:mime-version:references :mail-followup-to:message-id:subject:cc:to:from:date:from:to:cc :subject:date:message-id:reply-to; bh=ac4TBOhO4Lvkf/O2AokVMuwcwMPMmOE7Ro7pJm1rvQk=; b=rh6Vclza4LMKzzamya67wQux9FsAtk9CbTUQabpSc9m924ii8ZWt2uYLMh0RN+2sEM Udp3JOJiincJrjZhaaaa1B2xZuWuoIVIcjpWt6criqFnyIM5ZbOXFc5C10DQ/thOY92J FUECVEofWJ7Ye0KlJb4q8JblE7N/d/E3uYwnE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1721665055; x=1722269855; h=in-reply-to:content-disposition:mime-version:references :mail-followup-to:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=ac4TBOhO4Lvkf/O2AokVMuwcwMPMmOE7Ro7pJm1rvQk=; b=wrKIylxjwmmrtV1iwiO1lgOXcKbAKQVyvuYsI63G8gIebXY7NbkhpM42OopZX/9+Th oVf8oAH6dal3wdQPKF4OVumY45FDJwYtfwdIIo0hWla6e3MJpmxarEBf67oxYNMqCBzb e+5n2LscqkPKy8/Tg6ZYPj2igq4RQytbkgm53WUqHdYamJHqMc2zhthShUofUkNpQDdg SWCQHDNHnBJn1s7fVsxK1nnJMO+3++NWVGPzBAPjjFx2wyedvIeYQenjWsVf2d3oNuTo SxpIP4+SuewWkk+Dhrn+l8yycwWC7IOlY0Dp0uxORkS+kI4AHDEF1N/XsIWYrnq8o+Cu ZdqQ== X-Forwarded-Encrypted: i=1; AJvYcCXbaSaiURnKnC5+8cJZ7wJSPv3LFk2AN6O/Y9ekilhiEWaavAqi0jc+5+JoMtOTycekhaPbm9DjWNM+iClRSlAdNxLN35AZ9pNN+hLzX26HeqoV X-Gm-Message-State: AOJu0Yx0bS2UHQfUzrEpwXgCwbXOV3+L2o8t/u+rWg5hfQQuYMBwqMuc Q3aisf2v6Rt8GylM8Agava3xAZJaoaVnuULwO5Dgr6RXP1DU69dmKbDSrwqrFmE= X-Google-Smtp-Source: AGHT+IFB2y7zOFl4+Y01VeT43wEsBkhPo0FQ49eT3GIcwc/I7mB7L8n/Y/dKG9HTsZ7eJjeY9OWniQ== X-Received: by 2002:a17:902:cec4:b0:1fd:b5fe:ee91 with SMTP id d9443c01a7336-1fdb5fef138mr3886125ad.25.1721665054849; Mon, 22 Jul 2024 09:17:34 -0700 (PDT) Received: from LQ3V64L9R2 (c-24-6-151-244.hsd1.ca.comcast.net. [24.6.151.244]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-70d1dbfe395sm2640504b3a.218.2024.07.22.09.17.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 22 Jul 2024 09:17:34 -0700 (PDT) Date: Mon, 22 Jul 2024 09:17:31 -0700 From: Joe Damato To: Elad Yifee Cc: daniel@makrotopia.org, Felix Fietkau , Sean Wang , Mark Lee , Lorenzo Bianconi , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Matthias Brugger , AngeloGioacchino Del Regno , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, bpf@vger.kernel.org Subject: Re: [PATCH net-next RFC] net: ethernet: mtk_eth_soc: use prefetch methods Message-ID: Mail-Followup-To: Joe Damato , Elad Yifee , daniel@makrotopia.org, Felix Fietkau , Sean Wang , Mark Lee , Lorenzo Bianconi , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Matthias Brugger , AngeloGioacchino Del Regno , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, bpf@vger.kernel.org References: <20240720164621.1983-1-eladwf@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240720164621.1983-1-eladwf@gmail.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240722_091736_459023_35FA3202 X-CRM114-Status: GOOD ( 20.08 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org On Sat, Jul 20, 2024 at 07:46:18PM +0300, Elad Yifee wrote: > Utilize kernel prefetch methods for faster cache line access. > This change boosts driver performance, > allowing the CPU to handle about 5% more packets/sec. Nit: It'd be great to see before/after numbers and/or an explanation of how you measured this in the commit message. > Signed-off-by: Elad Yifee > --- > drivers/net/ethernet/mediatek/mtk_eth_soc.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c > index 0cc2dd85652f..1a0704166103 100644 > --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c > +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c > @@ -1963,6 +1963,7 @@ static u32 mtk_xdp_run(struct mtk_eth *eth, struct mtk_rx_ring *ring, > if (!prog) > goto out; > > + prefetchw(xdp->data_hard_start); Is there any reason to mix net_prefetch (as you have below) with prefetch and prefetchw ? IMHO: you should consider using net_prefetch and net_prefetchw everywhere instead of using both in your code. > act = bpf_prog_run_xdp(prog, xdp); > switch (act) { > case XDP_PASS: > @@ -2039,7 +2040,7 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget, > idx = NEXT_DESP_IDX(ring->calc_idx, ring->dma_size); > rxd = ring->dma + idx * eth->soc->rx.desc_size; > data = ring->data[idx]; > - > + prefetch(rxd); Maybe net_prefetch instead, as mentioned above? > if (!mtk_rx_get_desc(eth, &trxd, rxd)) > break; > > @@ -2105,6 +2106,7 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget, > if (ret != XDP_PASS) > goto skip_rx; > > + net_prefetch(xdp.data_meta); > skb = build_skb(data, PAGE_SIZE); > if (unlikely(!skb)) { > page_pool_put_full_page(ring->page_pool, > @@ -2113,6 +2115,7 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget, > goto skip_rx; > } > > + prefetchw(skb->data); Maybe net_prefetchw instead, as mentioned above? > skb_reserve(skb, xdp.data - xdp.data_hard_start); > skb_put(skb, xdp.data_end - xdp.data); > skb_mark_for_recycle(skb); > @@ -2143,6 +2146,7 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget, > dma_unmap_single(eth->dma_dev, ((u64)trxd.rxd1 | addr64), > ring->buf_size, DMA_FROM_DEVICE); > > + net_prefetch(data); > skb = build_skb(data, ring->frag_size); > if (unlikely(!skb)) { > netdev->stats.rx_dropped++; > @@ -2150,6 +2154,7 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget, > goto skip_rx; > } > > + prefetchw(skb->data); Maybe net_prefetchw instead, as mentioned above?