Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753123Ab2EHKN1 (ORCPT ); Tue, 8 May 2012 06:13:27 -0400 Received: from violet.fr.zoreil.com ([92.243.8.30]:56979 "EHLO violet" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752385Ab2EHKN0 (ORCPT ); Tue, 8 May 2012 06:13:26 -0400 Date: Tue, 8 May 2012 12:06:57 +0200 From: Francois Romieu To: Alex =?utf-8?B?VmlsbGFjw63CrXM=?= Lasso Cc: Thomas Pilarski , Julien Ducourthial , Hayes Wang , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] r8169: fix problem with TSO (TX_BUFFS_AVAIL negative value) Message-ID: <20120508100657.GA10744@electric-eye.fr.zoreil.com> References: <1336430367.11363.38.camel@blackbone.local> <20120507234205.GA2230@electric-eye.fr.zoreil.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120507234205.GA2230@electric-eye.fr.zoreil.com> User-Agent: Mutt/1.4.2.2i X-Organisation: Land of Sunshine Inc. Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2528 Lines: 73 Francois Romieu : [...] > Alex, Thomas, can you check if Julien's patch below fixes your broken > kernels as well ? You will have better luck with a patch whose lines are correctly formed. Patch below applies on top of 3.4-rc6. (Julien, please check your mail user agent) diff --git a/drivers/net/ethernet/realtek/r8169.c b/drivers/net/ethernet/realtek/r8169.c index f545093..d1e3c51 100644 --- a/drivers/net/ethernet/realtek/r8169.c +++ b/drivers/net/ethernet/realtek/r8169.c @@ -61,8 +61,12 @@ #define R8169_MSG_DEFAULT \ (NETIF_MSG_DRV | NETIF_MSG_PROBE | NETIF_MSG_IFUP | NETIF_MSG_IFDOWN) -#define TX_BUFFS_AVAIL(tp) \ - (tp->dirty_tx + NUM_TX_DESC - tp->cur_tx - 1) +#define TX_SLOTS_AVAIL(tp) \ + (tp->dirty_tx + NUM_TX_DESC - tp->cur_tx) + +/* A skbuff with nr_frags needs nr_frags+1 entries in the tx queue */ +#define TX_FRAGS_READY_FOR(tp,nr_frags) \ + (TX_SLOTS_AVAIL(tp) >= (nr_frags + 1)) /* Maximum number of multicast addresses to filter (vs. Rx-all-multicast). The RTL chips use a 64 element hash table based on the Ethernet CRC. */ @@ -5115,7 +5119,7 @@ static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb, u32 opts[2]; int frags; - if (unlikely(TX_BUFFS_AVAIL(tp) < skb_shinfo(skb)->nr_frags)) { + if (unlikely(!TX_FRAGS_READY_FOR(tp, skb_shinfo(skb)->nr_frags))) { netif_err(tp, drv, dev, "BUG! Tx Ring full when queue awake!\n"); goto err_stop_0; } @@ -5169,7 +5173,7 @@ static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb, mmiowb(); - if (TX_BUFFS_AVAIL(tp) < MAX_SKB_FRAGS) { + if (!TX_FRAGS_READY_FOR(tp, MAX_SKB_FRAGS)) { /* Avoid wrongly optimistic queue wake-up: rtl_tx thread must * not miss a ring update when it notices a stopped queue. */ @@ -5183,7 +5187,7 @@ static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb, * can't. */ smp_mb(); - if (TX_BUFFS_AVAIL(tp) >= MAX_SKB_FRAGS) + if (TX_FRAGS_READY_FOR(tp, MAX_SKB_FRAGS)) netif_wake_queue(dev); } @@ -5306,7 +5310,7 @@ static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp) */ smp_mb(); if (netif_queue_stopped(dev) && - (TX_BUFFS_AVAIL(tp) >= MAX_SKB_FRAGS)) { + TX_FRAGS_READY_FOR(tp, MAX_SKB_FRAGS)) { netif_wake_queue(dev); } /* -- Ueimor -- 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/