Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754342AbXLGLLo (ORCPT ); Fri, 7 Dec 2007 06:11:44 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751889AbXLGLLe (ORCPT ); Fri, 7 Dec 2007 06:11:34 -0500 Received: from smtp2.linux-foundation.org ([207.189.120.14]:45892 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751303AbXLGLLd (ORCPT ); Fri, 7 Dec 2007 06:11:33 -0500 Date: Fri, 7 Dec 2007 03:09:54 -0800 From: Andrew Morton To: Ingo Molnar Cc: Stefano Brivio , Robert Love , linux-kernel@vger.kernel.org, Dave Jones , "Rafael J. Wysocki" , Michael Buesch , Thomas Gleixner , Len Brown Subject: Re: [PATCH] scheduler: fix x86 regression in native_sched_clock Message-Id: <20071207030954.8c1fedc5.akpm@linux-foundation.org> In-Reply-To: <20071207104013.GC27307@elte.hu> References: <20071207021952.6f0ac922@morte> <20071207084559.GA11162@elte.hu> <20071207023241.15274ef6.akpm@linux-foundation.org> <20071207104013.GC27307@elte.hu> X-Mailer: Sylpheed 2.4.1 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 963 Lines: 27 On Fri, 7 Dec 2007 11:40:13 +0100 Ingo Molnar wrote: > > * Andrew Morton wrote: > > > > - t = printk_clock(); > > > + t = cpu_clock(printk_cpu); > > > nanosec_rem = do_div(t, 1000000000); > > > tlen = sprintf(tbuf, > > > "<%c>[%5lu.%06lu] ", > > > > A bit risky - it's quite an expansion of code which no longer can call > > printk. > > > > You might want to take that WARN_ON out of __update_rq_clock() ;) > > hm, dont we already detect printk recursions and turn them into a silent > return instead of a hang/crash? > We'll pop the locks and will proceed to do the nested printk. So __update_rq_clock() will need rather a lot of stack ;) -- 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/