From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Kirsher Subject: [net-2.6 PATCH 3/3] ixgbe: Fix RSC completion delay causing Rx interrupts to stop Date: Thu, 30 Jul 2009 15:26:00 -0700 Message-ID: <20090730222559.26121.13496.stgit@localhost.localdomain> References: <20090730222501.26121.2952.stgit@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, gospo@redhat.com, Peter P Waskiewicz Jr , Jeff Kirsher To: davem@davemloft.net Return-path: Received: from qmta08.emeryville.ca.mail.comcast.net ([76.96.30.80]:56062 "EHLO QMTA08.emeryville.ca.mail.comcast.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752551AbZG3W0Q (ORCPT ); Thu, 30 Jul 2009 18:26:16 -0400 In-Reply-To: <20090730222501.26121.2952.stgit@localhost.localdomain> Sender: netdev-owner@vger.kernel.org List-ID: From: Peter P Waskiewicz Jr When a user disables interrupt throttling with ethtool on 82599 devices, the interrupt timer may not be re-enabled if hardware RSC is running. The RSC completions in hardware don't complete before the next ITR event tries to fire, so the ITR timer never gets re-armed. This patch increases the amount of time between interrupts when throttling is disabled (rx-usecs = 0) when the hardware RSC deature is enabled. Signed-off-by: Peter P Waskiewicz Jr Signed-off-by: Jeff Kirsher --- drivers/net/ixgbe/ixgbe.h | 2 ++ drivers/net/ixgbe/ixgbe_ethtool.c | 5 ++++- 2 files changed, 6 insertions(+), 1 deletions(-) diff --git a/drivers/net/ixgbe/ixgbe.h b/drivers/net/ixgbe/ixgbe.h index 1b12c7b..e11d83d 100644 --- a/drivers/net/ixgbe/ixgbe.h +++ b/drivers/net/ixgbe/ixgbe.h @@ -96,6 +96,8 @@ #define IXGBE_TX_FLAGS_VLAN_PRIO_MASK 0x0000e000 #define IXGBE_TX_FLAGS_VLAN_SHIFT 16 +#define IXGBE_MAX_RSC_INT_RATE 162760 + /* wrapper around a pointer to a socket buffer, * so a DMA handle can be stored along with the buffer */ struct ixgbe_tx_buffer { diff --git a/drivers/net/ixgbe/ixgbe_ethtool.c b/drivers/net/ixgbe/ixgbe_ethtool.c index 7ddb50c..79144e9 100644 --- a/drivers/net/ixgbe/ixgbe_ethtool.c +++ b/drivers/net/ixgbe/ixgbe_ethtool.c @@ -1975,7 +1975,10 @@ static int ixgbe_set_coalesce(struct net_device *netdev, * any other value means disable eitr, which is best * served by setting the interrupt rate very high */ - adapter->eitr_param = IXGBE_MAX_INT_RATE; + if (adapter->flags2 & IXGBE_FLAG2_RSC_ENABLED) + adapter->eitr_param = IXGBE_MAX_RSC_INT_RATE; + else + adapter->eitr_param = IXGBE_MAX_INT_RATE; adapter->itr_setting = 0; }