From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] vmxnet3: fix starving rx ring whenoc_skb kb fails Date: Tue, 05 Jul 2011 18:40:35 -0700 (PDT) Message-ID: <20110705.184035.2294830861687805068.davem@davemloft.net> References: <1308312860.11457.56.camel@localhost> <20110617.120900.550060204741705506.davem@davemloft.net> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: bhutchings@solarflare.com, pv-drivers@vmware.com, netdev@vger.kernel.org, scottjg@vmware.com To: sbhatewara@vmware.com Return-path: Received: from shards.monkeyblade.net ([198.137.202.13]:51030 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755445Ab1GFBkh (ORCPT ); Tue, 5 Jul 2011 21:40:37 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: From: Shreyas Bhatewara Date: Tue, 5 Jul 2011 17:34:05 -0700 (PDT) > > If the rx ring is completely empty, then the device may never fire an rx > interrupt. Unfortunately, the rx interrupt is what triggers populating the > rx ring with fresh buffers, so this will cause networking to lock up. > > This patch replenishes the skb in recv descriptor as soon as it is > peeled off while processing rx completions. If the skb/buffer > allocation fails, existing one is recycled and the packet in hand is > dropped. This way none of the RX desc is ever left empty, thus avoiding > starvation > > Signed-off-by: Scott J. Goldman > Signed-off-by: Shreyas N Bhatewara Applied.