Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753254Ab3GYFLF (ORCPT ); Thu, 25 Jul 2013 01:11:05 -0400 Received: from mail-vb0-f45.google.com ([209.85.212.45]:37450 "EHLO mail-vb0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751436Ab3GYFLC (ORCPT ); Thu, 25 Jul 2013 01:11:02 -0400 Message-ID: <1374729058.23313.8.camel@edumazet-glaptop> Subject: Re: [PATCH 1/1] TX throttling bug-fixing patch of AX88179_178A From: Eric Dumazet To: Ming Lei Cc: Ben Hutchings , Oliver Neukum , Grant Grundler , Freddy Xin , David Miller , netdev , linux-usb@vger.kernel.org, LKML , ASIX Louis =?UTF-8?Q?=5B=E8=98=87=E5=A8=81=E9=99=B8=5D?= , Allan Chou Date: Wed, 24 Jul 2013 22:10:58 -0700 In-Reply-To: References: <1374311809-4155-1-git-send-email-freddy@asix.com.tw> <1374512879.4990.19.camel@edumazet-glaptop> <1374518312.1635.29.camel@bwh-desktop.uk.level5networks.com> <1374518841.4990.26.camel@edumazet-glaptop> <1374522471.1635.48.camel@bwh-desktop.uk.level5networks.com> <1374559827.4990.143.camel@edumazet-glaptop> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 973 Lines: 26 On Thu, 2013-07-25 at 10:28 +0800, Ming Lei wrote: > > It depends if size of sg buffer(except for last one) in the sg list can be > divided by usb endpoint's max packet size(512 or 1024), at least there > is the constraint: > > http://git.kernel.org/cgit/linux/kernel/git/gregkh/usb.git/commit/?h=usb-next&id=10e232c597ac757e7f8600649f7e872e86de190f > > I am wondering if network stack can meet that. If not, it might be a > bit difficult > because lots of USB host controller don't support that, and driver may have > to support SG and non-SG at the same time for working well on all HCs. I do not see the problem. If one skb has 2 fragments of 32KB, couldn't they be split into 64 1K segments by the device driver ? -- 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/