From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] dummy: fix rcu_sched self-detected stalls Date: Sun, 10 Jun 2012 22:48:00 -0700 (PDT) Message-ID: <20120610.224800.602807319671005890.davem@davemloft.net> References: <1339239546.6001.177.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: eric.dumazet@gmail.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:39978 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751287Ab2FKFsD (ORCPT ); Mon, 11 Jun 2012 01:48:03 -0400 In-Reply-To: <1339239546.6001.177.camel@edumazet-glaptop> Sender: netdev-owner@vger.kernel.org List-ID: From: Eric Dumazet Date: Sat, 09 Jun 2012 12:59:06 +0200 > From: Eric Dumazet > > Trying to "modprobe dummy numdummies=30000" triggers : > > INFO: rcu_sched self-detected stall on CPU { 8} (t=60000 jiffies) > > After this splat, RTNL is locked and reboot is needed. > > We must call cond_resched() to avoid this, even holding RTNL. > > Also remove the ~32767 limit on number of dummies (PAGE_SIZE*8) > > Tested with "modprobe dummy numdummies=128000" > (it took ~12 minutes, because of sysfs) > > Signed-off-by: Eric Dumazet I'm all for the cond_resched() change, but the name optimization belongs generically in net/core/dev.c not in specific drivers. So, please submit this cond_resched() fix first then we can work on the naming performance issue. Thanks.