From patchwork Thu Nov 12 11:55:42 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sriram X-Patchwork-Id: 38240 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 [209.132.176.167]) by ozlabs.org (Postfix) with ESMTP id 9D389B7B7C for ; Thu, 12 Nov 2009 22:55:52 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752666AbZKLLzl (ORCPT ); Thu, 12 Nov 2009 06:55:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752230AbZKLLzl (ORCPT ); Thu, 12 Nov 2009 06:55:41 -0500 Received: from bear.ext.ti.com ([192.94.94.41]:38598 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752163AbZKLLzk (ORCPT ); Thu, 12 Nov 2009 06:55:40 -0500 Received: from dbdp31.itg.ti.com ([172.24.170.98]) by bear.ext.ti.com (8.13.7/8.13.7) with ESMTP id nACBthOw026593 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Thu, 12 Nov 2009 05:55:46 -0600 Received: from psplinux050.india.ti.com (localhost [127.0.0.1]) by dbdp31.itg.ti.com (8.13.8/8.13.8) with ESMTP id nACBtgPr006698; Thu, 12 Nov 2009 17:25:42 +0530 (IST) Received: from psplinux050.india.ti.com (localhost [127.0.0.1]) by psplinux050.india.ti.com (8.13.1/8.13.1) with ESMTP id nACBtgst004345; Thu, 12 Nov 2009 17:25:42 +0530 Received: (from a0875517@localhost) by psplinux050.india.ti.com (8.13.1/8.13.1/Submit) id nACBtgeY004340; Thu, 12 Nov 2009 17:25:42 +0530 From: Sriramakrishnan To: netdev@vger.kernel.org Cc: Sriramakrishnan Subject: [PATCH] TI Davinci EMAC : Fix Console Hang when bringing the interface down Date: Thu, 12 Nov 2009 17:25:42 +0530 Message-Id: <1258026942-2947-1-git-send-email-srk@ti.com> X-Mailer: git-send-email 1.6.2.4 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org In the NAPI poll function(emac_poll), check for netif_running() is unnecassary. In addition to associated runtime overhead, it also results in a continuous softirq loop when the interface is brought down under heavy traffic(tested wit Traffic Generator). Once the interface is disabled, the poll function always returns zero(with the check for netif_running) and napi_complete() would never get called resulting in softirq loop. Signed-off-by: Sriramakrishnan Acked-by: Chaithrika U S --- This patch has been validated on the OMAP-L138 platform. The smsc911x driver has a similar issue. Will post a patch for that separately. drivers/net/davinci_emac.c | 3 --- 1 files changed, 0 insertions(+), 3 deletions(-) diff --git a/drivers/net/davinci_emac.c b/drivers/net/davinci_emac.c index f72c56d..2533413 100644 --- a/drivers/net/davinci_emac.c +++ b/drivers/net/davinci_emac.c @@ -2140,9 +2140,6 @@ static int emac_poll(struct napi_struct *napi, int budget) u32 status = 0; u32 num_pkts = 0; - if (!netif_running(ndev)) - return 0; - /* Check interrupt vectors and call packet processing */ status = emac_read(EMAC_MACINVECTOR);