From patchwork Tue Dec 18 13:51:51 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ian Campbell X-Patchwork-Id: 207122 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 836222C0085 for ; Wed, 19 Dec 2012 00:57:28 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754979Ab2LRN50 (ORCPT ); Tue, 18 Dec 2012 08:57:26 -0500 Received: from smtp02.citrix.com ([66.165.176.63]:19271 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754769Ab2LRN5Z (ORCPT ); Tue, 18 Dec 2012 08:57:25 -0500 X-IronPort-AV: E=Sophos;i="4.84,309,1355097600"; d="scan'208";a="1033426" Received: from unknown (HELO FTLPEX01CL03.citrite.net) ([10.13.107.80]) by FTLPIPO02.CITRIX.COM with ESMTP/TLS/AES128-SHA; 18 Dec 2012 13:57:24 +0000 Received: from ukmail1.uk.xensource.com (10.80.16.128) by smtprelay.citrix.com (10.13.107.80) with Microsoft SMTP Server id 14.2.318.1; Tue, 18 Dec 2012 08:57:24 -0500 Received: from cosworth.uk.xensource.com ([10.80.16.52] ident=ianc) by ukmail1.uk.xensource.com with esmtp (Exim 4.69) (envelope-from ) id 1TkxaJ-0006Mf-Sq; Tue, 18 Dec 2012 13:51:51 +0000 From: Ian Campbell To: CC: Ian Campbell , Sander Eikelenboom , Konrad Rzeszutek Wilk , "annie li" , Subject: [PATCH] xen/netfront: improve truesize tracking Date: Tue, 18 Dec 2012 13:51:51 +0000 Message-ID: <1355838711-5473-1-git-send-email-ian.campbell@citrix.com> X-Mailer: git-send-email 1.7.2.5 MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Using RX_COPY_THRESHOLD is incorrect if the SKB is actually smaller than that. We have already accounted for this in NETFRONT_SKB_CB(skb)->pull_to so use that instead. Fixes WARN_ON from skb_try_coalesce. Signed-off-by: Ian Campbell Cc: Sander Eikelenboom Cc: Konrad Rzeszutek Wilk Cc: annie li Cc: xen-devel@lists.xensource.com Cc: netdev@vger.kernel.org Cc: stable@kernel.org # 3.7.x only --- drivers/net/xen-netfront.c | 15 +++++---------- 1 files changed, 5 insertions(+), 10 deletions(-) diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index caa0110..b06ef81 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -971,17 +971,12 @@ err: * overheads. Here, we add the size of the data pulled * in xennet_fill_frags(). * - * We also adjust for any unused space in the main - * data area by subtracting (RX_COPY_THRESHOLD - - * len). This is especially important with drivers - * which split incoming packets into header and data, - * using only 66 bytes of the main data area (see the - * e1000 driver for example.) On such systems, - * without this last adjustement, our achievable - * receive throughout using the standard receive - * buffer size was cut by 25%(!!!). + * We also adjust for the __pskb_pull_tail done in + * handle_incoming_queue which pulls data from the + * frags into the head area, which is already + * accounted in RX_COPY_THRESHOLD. */ - skb->truesize += skb->data_len - RX_COPY_THRESHOLD; + skb->truesize += skb->data_len - NETFRONT_SKB_CB(skb)->pull_to; skb->len += skb->data_len; if (rx->flags & XEN_NETRXF_csum_blank)