From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964975AbXBLQvd (ORCPT ); Mon, 12 Feb 2007 11:51:33 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964985AbXBLQvd (ORCPT ); Mon, 12 Feb 2007 11:51:33 -0500 Received: from mx1.suse.de ([195.135.220.2]:47919 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964975AbXBLQvb (ORCPT ); Mon, 12 Feb 2007 11:51:31 -0500 From: Andi Kleen References: <20070212551.664370000@suse.de> In-Reply-To: <20070212551.664370000@suse.de> To: Roland Dreier , patches@x86-64.org, linux-kernel@vger.kernel.org Subject: [PATCH x86 for review III] [8/29] x86_64: avoid warning message livelock Message-Id: <20070212165128.2460213FC3@wotan.suse.de> Date: Mon, 12 Feb 2007 17:51:28 +0100 (CET) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org From: Roland Dreier I've seen my box paralyzed by an endless spew of rtc: lost some interrupts at 1024Hz. messages on the serial console. What seems to be happening is that something real causes an interrupt to be lost and triggers the message. But then printing the message to the serial console (from the hpet interrupt handler) takes more than 1/1024th of a second, and then some more interrupts are lost, so the message triggers again.... Fix this by adding a printk_ratelimit() before printing the warning. Signed-off-by: Roland Dreier Signed-off-by: Andrew Morton Signed-off-by: Andi Kleen --- arch/x86_64/kernel/time.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) Index: linux/arch/x86_64/kernel/time.c =================================================================== --- linux.orig/arch/x86_64/kernel/time.c +++ linux/arch/x86_64/kernel/time.c @@ -1226,8 +1226,9 @@ static void hpet_rtc_timer_reinit(void) if (PIE_on) PIE_count += lost_ints; - printk(KERN_WARNING "rtc: lost some interrupts at %ldHz.\n", - hpet_rtc_int_freq); + if (printk_ratelimit()) + printk(KERN_WARNING "rtc: lost some interrupts at %ldHz.\n", + hpet_rtc_int_freq); } }