From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2992960AbXDDPhm (ORCPT ); Wed, 4 Apr 2007 11:37:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S2992963AbXDDPhm (ORCPT ); Wed, 4 Apr 2007 11:37:42 -0400 Received: from gateway-1237.mvista.com ([63.81.120.158]:21839 "EHLO gateway-1237.mvista.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2992960AbXDDPhl (ORCPT ); Wed, 4 Apr 2007 11:37:41 -0400 Subject: Re: real time hang w/ latency tracing From: Daniel Walker To: Ingo Molnar Cc: linux-kernel@vger.kernel.org In-Reply-To: <20070404085133.GC2521@elte.hu> References: <1175626625.10738.21.camel@imap.mvista.com> <1175650887.3722.2.camel@dwalker1> <20070404085133.GC2521@elte.hu> Content-Type: text/plain Date: Wed, 04 Apr 2007 08:36:53 -0700 Message-Id: <1175701013.15973.8.camel@imap.mvista.com> Mime-Version: 1.0 X-Mailer: Evolution 2.8.2.1 (2.8.2.1-3.fc6) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2007-04-04 at 10:51 +0200, Ingo Molnar wrote: > * Daniel Walker wrote: > > > Index: linux-2.6.20/include/linux/serial_core.h > > =================================================================== > > --- linux-2.6.20.orig/include/linux/serial_core.h > > +++ linux-2.6.20/include/linux/serial_core.h > > @@ -213,7 +213,11 @@ struct uart_icount { > > typedef unsigned int __bitwise__ upf_t; > > > > struct uart_port { > > +#ifdef CONFIG_LATENCY_TIMING > > + raw_spinlock_t lock; /* port lock */ > > +#else > > spinlock_t lock; /* port lock */ > > +#endif > > ugh - this will only cause other problems if anyone else is trying to > use the serial code. This needs a cleaner fix - such as not doing that > printk from atomic context. I assumed this fix wasn't totally right .. Interrupts could be enabled just before printing , after any critical stuff has happened then disabled again after printing .. Or are you thinking of something more complex? Daniel