Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933934AbaFQUHq (ORCPT ); Tue, 17 Jun 2014 16:07:46 -0400 Received: from exprod5og126.obsmtp.com ([64.18.0.251]:34700 "HELO exprod5og126.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S932927AbaFQUHp (ORCPT ); Tue, 17 Jun 2014 16:07:45 -0400 MIME-Version: 1.0 In-Reply-To: References: <1402964326-11147-1-git-send-email-isubramanian@apm.com> <1402964326-11147-5-git-send-email-isubramanian@apm.com> <20140616.214247.1154200670003936158.davem@davemloft.net> Date: Tue, 17 Jun 2014 13:07:42 -0700 Message-ID: Subject: Re: [PATCH v6 4/4] drivers: net: Add APM X-Gene SoC ethernet driver support. From: Iyappan Subramanian To: Florian Fainelli Cc: David Miller , "devicetree@vger.kernel.org" , Greg KH , netdev , patches , "linux-kernel@vger.kernel.org" , "jcm@redhat.com" , Keyur Chudgar , "linux-arm-kernel@lists.infradead.org" , Ravi Patel Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 17, 2014 at 12:24 PM, Florian Fainelli wrote: > 2014-06-17 12:21 GMT-07:00 Iyappan Subramanian : >> On Mon, Jun 16, 2014 at 9:42 PM, David Miller wrote: >>> From: Iyappan Subramanian >>> Date: Mon, 16 Jun 2014 17:18:46 -0700 >>> >>>> +static netdev_tx_t xgene_enet_start_xmit(struct sk_buff *skb, >>>> + struct net_device *ndev) >>>> +{ >>>> + struct xgene_enet_pdata *pdata = netdev_priv(ndev); >>>> + struct xgene_enet_desc_ring *tx_ring = pdata->tx_ring; >>>> + struct xgene_enet_desc_ring *cp_ring = tx_ring->cp_ring; >>>> + u32 tx_level, cq_level; >>>> + >>>> + tx_level = xgene_enet_ring_len(tx_ring); >>>> + cq_level = xgene_enet_ring_len(cp_ring); >>>> + if (unlikely(tx_level > pdata->tx_qcnt_hi || >>>> + cq_level > pdata->cp_qcnt_hi)) { >>>> + netif_stop_queue(ndev); >>>> + return NETDEV_TX_BUSY; >>>> + } >>>> + >>>> + if (xgene_enet_setup_tx_desc(tx_ring, skb)) >>>> + return NETDEV_TX_OK; >>> >>> If you return NETDEV_TX_OK, it is your responsibility to deal with the >>> SKB, because you own it. >>> >>> In particular, you have to free the packet. >> >> skb freeing happens in xgene_enet_tx_completion(). > > I have not looked at what xgenet_enet_setup_tx_desc() does, but > David's point is that, if this function fails and has not yet been > able to queue the SKB for transmission at the HW, you should make sure > that you free the SKB. Is xgene_enet_tx_completion() called if the > driver failed to prepare a descriptor for a SKB? Thanks for the explanation. I will free up skb when xgene_enet_setup_tx_desc() fails and submit the next patch shortly. > -- > Florian -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/