From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-177.mta0.migadu.com (out-177.mta0.migadu.com [91.218.175.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 72BED21ADBE for ; Mon, 13 Jan 2025 09:42:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.177 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736761374; cv=none; b=kWhzMe9ccK8trf/jCexDa7vOBy6OBc7/R4w/QvxyAJa40rJaBrkGAA11moeubl4zr5qaPkm+P+Qzv/QqmeVs0lKzrNhVzmX/IZC7QZCy7TTDW51ELMwi6cEvW3TqKv8odBwCZ+QlwyFKAS6nStZ+77th+I8T9otycDhk3HdTxx0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736761374; c=relaxed/simple; bh=lhmxskbqGmXej7W9jkDId4T2R4B5O0rubVPO9ENh8cs=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=UGHGtgjrGvwk2/Rbs/NR+w2mw7oERg8Tr3E50TsQfCVIhhHSTEgf4EtiimYY/0STi9Ktk8TzgbFjKt+/h06InQqlag7cKHKSW39f61gdOlfz4/RPl5zlTVWvnZYU5erXO9EQuB1Q1trbgreGyjnBtwTyEHIBT03TzA6iY9VR0Fc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=FSvBoOR/; arc=none smtp.client-ip=91.218.175.177 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="FSvBoOR/" Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1736761355; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=RjB6WK0e1BonkXyM1rzb2pTfxLH0vAZTTZRJAaWMzIU=; b=FSvBoOR/2lGsPOrxt2XCfKh4xJt4s9aq0Soaqo+ujJeGo1zgsSoFjz/dbxC0X6Wt6Wzm1h gUnPg9mGmD2dnliNDp+r/yXxQpGllafOGvKp2C9uQVepdcAO9uVnIchrJHbE1UMid6zH6e feKvgHJ/zRi0H+1a5Gyl3/QcoKX+jIY= Date: Mon, 13 Jan 2025 17:41:41 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH net-next v1 1/3] net: stmmac: Switch to zero-copy in non-XDP RX path To: Furong Xu <0x1207@gmail.com>, netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Maxime Coquelin , xfr@outlook.com References: <600c76e88b6510f6a4635401ec1e224b3bbb76ec.1736500685.git.0x1207@gmail.com> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Yanteng Si In-Reply-To: <600c76e88b6510f6a4635401ec1e224b3bbb76ec.1736500685.git.0x1207@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT 在 2025/1/10 17:53, Furong Xu 写道: > Avoid memcpy in non-XDP RX path by marking all allocated SKBs to > be recycled in the upper network stack. > > This patch brings ~11.5% driver performance improvement in a TCP RX > throughput test with iPerf tool on a single isolated Cortex-A65 CPU > core, from 2.18 Gbits/sec increased to 2.43 Gbits/sec. > > Signed-off-by: Furong Xu <0x1207@gmail.com> > --- > drivers/net/ethernet/stmicro/stmmac/stmmac.h | 1 + > .../net/ethernet/stmicro/stmmac/stmmac_main.c | 23 +++++++++++-------- > 2 files changed, 15 insertions(+), 9 deletions(-) > > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h > index 548b28fed9b6..5c39292313de 100644 > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h > @@ -126,6 +126,7 @@ struct stmmac_rx_queue { > unsigned int cur_rx; > unsigned int dirty_rx; > unsigned int buf_alloc_num; > + unsigned int napi_skb_frag_size; > dma_addr_t dma_rx_phy; > u32 rx_tail_addr; > unsigned int state_saved; > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > index 038df1b2bb58..43125a6f8f6b 100644 > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > @@ -1320,7 +1320,7 @@ static unsigned int stmmac_rx_offset(struct stmmac_priv *priv) > if (stmmac_xdp_is_enabled(priv)) > return XDP_PACKET_HEADROOM; > > - return 0; > + return NET_SKB_PAD; > } > > static int stmmac_set_bfsize(int mtu, int bufsize) > @@ -2019,17 +2019,21 @@ static int __alloc_dma_rx_desc_resources(struct stmmac_priv *priv, > struct stmmac_channel *ch = &priv->channel[queue]; > bool xdp_prog = stmmac_xdp_is_enabled(priv); > struct page_pool_params pp_params = { 0 }; > - unsigned int num_pages; > + unsigned int dma_buf_sz_pad, num_pages; > unsigned int napi_id; > int ret; > > + dma_buf_sz_pad = stmmac_rx_offset(priv) + dma_conf->dma_buf_sz + > + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); > + num_pages = DIV_ROUND_UP(dma_buf_sz_pad, PAGE_SIZE); > + > rx_q->queue_index = queue; > rx_q->priv_data = priv; > + rx_q->napi_skb_frag_size = num_pages * PAGE_SIZE; > > pp_params.flags = PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV; > pp_params.pool_size = dma_conf->dma_rx_size; > - num_pages = DIV_ROUND_UP(dma_conf->dma_buf_sz, PAGE_SIZE); > - pp_params.order = ilog2(num_pages); > + pp_params.order = order_base_2(num_pages); > pp_params.nid = dev_to_node(priv->device); > pp_params.dev = priv->device; > pp_params.dma_dir = xdp_prog ? DMA_BIDIRECTIONAL : DMA_FROM_DEVICE; > @@ -5574,19 +5578,20 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue) > /* XDP program may expand or reduce tail */ > buf1_len = ctx.xdp.data_end - ctx.xdp.data; > > - skb = napi_alloc_skb(&ch->rx_napi, buf1_len); > + skb = napi_build_skb(page_address(buf->page), > + rx_q->napi_skb_frag_size); > if (!skb) { > + page_pool_recycle_direct(rx_q->page_pool, > + buf->page); > rx_dropped++; > count++; > goto drain_data; > } > > /* XDP program may adjust header */ > - skb_copy_to_linear_data(skb, ctx.xdp.data, buf1_len); > + skb_reserve(skb, ctx.xdp.data - ctx.xdp.data_hard_start); The network subsystem still requires that the length of each line of code should not exceed 80 characters. So let's silence the warning: WARNING: line length of 81 exceeds 80 columns #87: FILE: drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:5592: + skb_reserve(skb, ctx.xdp.data - ctx.xdp.data_hard_start); Thanks, Yanteng