From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754853Ab0IADAq (ORCPT ); Tue, 31 Aug 2010 23:00:46 -0400 Received: from mx1.redhat.com ([209.132.183.28]:22240 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754550Ab0IADA3 (ORCPT ); Tue, 31 Aug 2010 23:00:29 -0400 From: Don Zickus To: mingo@elte.hu Cc: peterz@infradead.org, gorcunov@gmail.com, fweisbec@gmail.com, linux-kernel@vger.kernel.org, Don Zickus Subject: [PATCH 1/3] [lockup detector] sync touch_*_watchdog back to old semantics Date: Tue, 31 Aug 2010 23:00:07 -0400 Message-Id: <1283310009-22168-2-git-send-email-dzickus@redhat.com> In-Reply-To: <1283310009-22168-1-git-send-email-dzickus@redhat.com> References: <1283310009-22168-1-git-send-email-dzickus@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org During my rewrite, the semantics of touch_nmi_watchdog and touch_softlockup_watchdog changed enough to break some drivers (mostly over preemptable regions). This change brings those touch_*_watchdog functions back in line to how they used to work. Signed-off-by: Don Zickus --- kernel/watchdog.c | 17 ++++++++++++----- 1 files changed, 12 insertions(+), 5 deletions(-) diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 0d53c8e..7f9c3c5 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -122,7 +122,7 @@ static void __touch_watchdog(void) void touch_softlockup_watchdog(void) { - __get_cpu_var(watchdog_touch_ts) = 0; + __raw_get_cpu_var(watchdog_touch_ts) = 0; } EXPORT_SYMBOL(touch_softlockup_watchdog); @@ -142,7 +142,14 @@ void touch_all_softlockup_watchdogs(void) #ifdef CONFIG_HARDLOCKUP_DETECTOR void touch_nmi_watchdog(void) { - __get_cpu_var(watchdog_nmi_touch) = true; + if (watchdog_enabled) { + unsigned cpu; + + for_each_present_cpu(cpu) { + if (per_cpu(watchdog_nmi_touch, cpu) != true) + per_cpu(watchdog_nmi_touch, cpu) = true; + } + } touch_softlockup_watchdog(); } EXPORT_SYMBOL(touch_nmi_watchdog); @@ -433,6 +440,9 @@ static int watchdog_enable(int cpu) wake_up_process(p); } + /* if any cpu succeeds, watchdog is considered enabled for the system */ + watchdog_enabled = 1; + return 0; } @@ -455,9 +465,6 @@ static void watchdog_disable(int cpu) per_cpu(softlockup_watchdog, cpu) = NULL; kthread_stop(p); } - - /* if any cpu succeeds, watchdog is considered enabled for the system */ - watchdog_enabled = 1; } static void watchdog_enable_all_cpus(void) -- 1.7.2.2