From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [PATCH v8 3/3] net: hisilicon: new hip04 ethernet driver Date: Wed, 10 Dec 2014 17:36:46 +0100 Message-ID: <34612839.hAkXUcbKUQ@wuerfel> References: <5487C357.9030507@huawei.com> <2331317.LV3gPP3odb@wuerfel> <20141210.110732.519666115784722516.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: In-Reply-To: <20141210.110732.519666115784722516.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org To: linux-arm-kernel@lists.infradead.org Cc: David Miller , mark.rutland@arm.com, devicetree@vger.kernel.org, f.fainelli@gmail.com, linux@arm.linux.org.uk, eric.dumazet@gmail.com, sergei.shtylyov@cogentembedded.com, netdev@vger.kernel.org, agraf@suse.de, xuwei5@hisilicon.com, David.Laight@aculab.com, dingtianhong@huawei.com, zhangfei.gao@linaro.org List-Id: devicetree@vger.kernel.org On Wednesday 10 December 2014 11:07:32 David Miller wrote: > From: Arnd Bergmann > Date: Wed, 10 Dec 2014 10:35:20 +0100 > > > On Wednesday 10 December 2014 14:45:29 Ding Tianhong wrote: > >> > >> Miss this code, I think the best way is skb_orphan(skb), just like the cxgb3 drivers, some hardware > >> didn't use the tx inq to free dmad Tx packages. > > > > The problem with skb_orphan is that you are telling the network stack that > > the packet is now out of its reach and it will no longer be able to take > > queued packets into account. > > skb_orphan() also does not release netfilter resources attached to the > packet. > > Really, all drivers must free TX SKBs in a small, finite, amount of > time after submission. > > There is no way around this. I see. Do you see a problem with returning early from napi->poll() without calling napi_complete() when the TX queue remains full at the end of the poll function? Or is there any better alternative for broken hardware that lacks a TX-complete interrupt? Arnd