From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Borkmann Subject: Re: [PATCH net-next] packet: respect devices with LLTX flag in direct xmit Date: Sun, 30 Mar 2014 23:52:04 +0200 Message-ID: <53389204.2010205@redhat.com> References: <1395934710-29182-1-git-send-email-dborkman@redhat.com> <20140328.165058.1610297081920676758.davem@davemloft.net> <5335E604.4020105@redhat.com> <1396105350.21428.6.camel@edumazet-glaptop2.roam.corp.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: David Miller , netdev@vger.kernel.org, brouer@redhat.com To: Eric Dumazet Return-path: Received: from mx1.redhat.com ([209.132.183.28]:25668 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751897AbaC3VwJ (ORCPT ); Sun, 30 Mar 2014 17:52:09 -0400 In-Reply-To: <1396105350.21428.6.camel@edumazet-glaptop2.roam.corp.google.com> Sender: netdev-owner@vger.kernel.org List-ID: On 03/29/2014 04:02 PM, Eric Dumazet wrote: > On Fri, 2014-03-28 at 22:13 +0100, Daniel Borkmann wrote: >> On 03/28/2014 09:50 PM, David Miller wrote: > >>> The only remaining issue is that Eric seems to suggest that a tx >>> dropped counter bump should be added. Please submit that as a >>> follow-on if my reading of his feedback is accurate. >> >> Yes, will do next week. I think at time of submission we didn't >> have that yet. :) > > BTW, how direct xmit performs in case of BQL enabled driver ? > > dummy is nice, but not really representative of real device ;) > > netif_xmit_frozen_or_stopped() tests (dev_queue->state & > QUEUE_STATE_ANY_XOFF_OR_FROZEN), so will not fill TX ring. > > Since you have no queue, I would rather use a test without > BQL bit (1 << __QUEUE_STATE_STACK_XOFF), so that you can absorb bursts > into TX ring ... Thanks Eric, I'll look into it on next Tuesday [I was on travel whole weekend and will be on Monday].