From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-185.mta0.migadu.com (out-185.mta0.migadu.com [91.218.175.185]) (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 98DF229711D for ; Fri, 23 May 2025 16:20:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.185 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748017244; cv=none; b=C8dGl/VGhraW1VePB2A7v0k9HsDfQOMQoNckMjDcSIKnnxhFEnQOYWGQIAJwR1XYd9QoHujr4WnAAqOQFTpmyHMTGw2PwTiL3ExMxaWV67MVKmI1ox98Kfp8BaN0Y8aRJHiq4Dh4qc1vbgppq6AGtV+Byhl4k/Ylv3iFYmQH8vc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748017244; c=relaxed/simple; bh=jGxO6861Lmn7/Z44Z7K3Do0qeo894R19psmFZQ+OepI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=sH7a9JOqDJNbUJPhvtkYPnlASYpA83Ff3ADFvAz/LtrlbIlv+4wrQeKsyekTFu6UFTN0AopCCD8QFqOoxGsFe5/T2ciEmuL7MFR7Wkq7jJUbEs28d89wQ6B8YmK2ZjUPB4yEG4bh6iWE7Rkp6zj45XruOnSbWt4csFzDKQ83JcI= 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=aYBb8WPx; arc=none smtp.client-ip=91.218.175.185 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="aYBb8WPx" Message-ID: <57443336-2098-42c9-be6d-468cdbd9b312@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1748017230; 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=EqYcc7RAH3L3qXW8h+9jH0kK0v745MDC6DUdwNHLo7M=; b=aYBb8WPxMh1tdXa3jnwRwsd/FS5Q+vtqK13Hna190/W1z6kwQ/GTIW6Iqn97e6P/EGBDfU /GJ3WUyRfHkpElC6S9AB7d8ow9lfNsIyycZrc+j+xIrrA4aibhC1tgfjSUxvDdK6wxZ0iJ WyCi9JzSdI41Kdzbiqks1wYLnIV2wR0= Date: Fri, 23 May 2025 12:20:26 -0400 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH net] net: xilinx: axienet: Fix Tx skb circular buffer occupancy check in dmaengine xmit To: Suraj Gupta , andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, michal.simek@amd.com, radhey.shyam.pandey@amd.com, horms@kernel.org Cc: netdev@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, git@amd.com, harini.katakam@amd.com References: <20250521181608.669554-1-suraj.gupta2@amd.com> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Sean Anderson In-Reply-To: <20250521181608.669554-1-suraj.gupta2@amd.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT On 5/21/25 14:16, Suraj Gupta wrote: > In Dmaengine flow, driver maintains struct skbuf_dma_descriptor rings each > element of which corresponds to a skb. In Tx datapath, compare available > space in skb ring with number of skbs instead of skb fragments. > Replace x * (MAX_SKB_FRAGS) in netif_txq_completed_wake() and > netif_txq_maybe_stop() with x * (1 skb) to fix the comparison. > > Fixes: 6a91b846af85 ("net: axienet: Introduce dmaengine support") > Signed-off-by: Suraj Gupta > --- > drivers/net/ethernet/xilinx/xilinx_axienet_main.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c > index 1b7a653c1f4e..6011d7eae0c7 100644 > --- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c > +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c > @@ -880,7 +880,7 @@ static void axienet_dma_tx_cb(void *data, const struct dmaengine_result *result) > dev_consume_skb_any(skbuf_dma->skb); > netif_txq_completed_wake(txq, 1, len, > CIRC_SPACE(lp->tx_ring_head, lp->tx_ring_tail, TX_BD_NUM_MAX), > - 2 * MAX_SKB_FRAGS); > + 2); > } > > /** > @@ -914,7 +914,7 @@ axienet_start_xmit_dmaengine(struct sk_buff *skb, struct net_device *ndev) > > dma_dev = lp->tx_chan->device; > sg_len = skb_shinfo(skb)->nr_frags + 1; > - if (CIRC_SPACE(lp->tx_ring_head, lp->tx_ring_tail, TX_BD_NUM_MAX) <= sg_len) { > + if (CIRC_SPACE(lp->tx_ring_head, lp->tx_ring_tail, TX_BD_NUM_MAX) <= 1) { > netif_stop_queue(ndev); > if (net_ratelimit()) > netdev_warn(ndev, "TX ring unexpectedly full\n"); > @@ -964,7 +964,7 @@ axienet_start_xmit_dmaengine(struct sk_buff *skb, struct net_device *ndev) > txq = skb_get_tx_queue(lp->ndev, skb); > netdev_tx_sent_queue(txq, skb->len); > netif_txq_maybe_stop(txq, CIRC_SPACE(lp->tx_ring_head, lp->tx_ring_tail, TX_BD_NUM_MAX), > - MAX_SKB_FRAGS + 1, 2 * MAX_SKB_FRAGS); > + 1, 2); > > dmaengine_submit(dma_tx_desc); > dma_async_issue_pending(lp->tx_chan); Reviwed-by: Sean Anderson