X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Fsoftlockup.c;h=c828c2339cc9e8a8992df52f31756f8894c7f6b1;hb=bd8c540fe867c070810a3ef55541f41f7c189c9a;hp=c1d76552446e592bc132d8de37073ecb589a1629;hpb=75659ca0c10992dcb39258518368a0f6f56e935d;p=linux-2.6

diff --git a/kernel/softlockup.c b/kernel/softlockup.c
index c1d7655244..c828c2339c 100644
--- a/kernel/softlockup.c
+++ b/kernel/softlockup.c
@@ -49,12 +49,17 @@ static unsigned long get_timestamp(int this_cpu)
 	return cpu_clock(this_cpu) >> 30LL;  /* 2^30 ~= 10^9 */
 }
 
-void touch_softlockup_watchdog(void)
+static void __touch_softlockup_watchdog(void)
 {
 	int this_cpu = raw_smp_processor_id();
 
 	__raw_get_cpu_var(touch_timestamp) = get_timestamp(this_cpu);
 }
+
+void touch_softlockup_watchdog(void)
+{
+	__raw_get_cpu_var(touch_timestamp) = 0;
+}
 EXPORT_SYMBOL(touch_softlockup_watchdog);
 
 void touch_all_softlockup_watchdogs(void)
@@ -80,7 +85,7 @@ void softlockup_tick(void)
 	unsigned long now;
 
 	if (touch_timestamp == 0) {
-		touch_softlockup_watchdog();
+		__touch_softlockup_watchdog();
 		return;
 	}
 
@@ -95,12 +100,16 @@ void softlockup_tick(void)
 
 	/* do not print during early bootup: */
 	if (unlikely(system_state != SYSTEM_RUNNING)) {
-		touch_softlockup_watchdog();
+		__touch_softlockup_watchdog();
 		return;
 	}
 
 	now = get_timestamp(this_cpu);
 
+	/* Wake up the high-prio watchdog task every second: */
+	if (now > (touch_timestamp + 1))
+		wake_up_process(per_cpu(watchdog_task, this_cpu));
+
 	/* Warn about unreasonable delays: */
 	if (now <= (touch_timestamp + softlockup_thresh))
 		return;
@@ -191,11 +200,11 @@ static void check_hung_uninterruptible_tasks(int this_cpu)
 	read_lock(&tasklist_lock);
 	do_each_thread(g, t) {
 		if (!--max_count)
-			break;
+			goto unlock;
 		if (t->state & TASK_UNINTERRUPTIBLE)
 			check_hung_task(t, now);
 	} while_each_thread(g, t);
-
+ unlock:
 	read_unlock(&tasklist_lock);
 }
 
@@ -210,23 +219,29 @@ static int watchdog(void *__bind_cpu)
 	sched_setscheduler(current, SCHED_FIFO, &param);
 
 	/* initialize timestamp */
-	touch_softlockup_watchdog();
+	__touch_softlockup_watchdog();
 
+	set_current_state(TASK_INTERRUPTIBLE);
 	/*
 	 * Run briefly once per second to reset the softlockup timestamp.
 	 * If this gets delayed for more than 60 seconds then the
 	 * debug-printout triggers in softlockup_tick().
 	 */
 	while (!kthread_should_stop()) {
-		touch_softlockup_watchdog();
-		msleep_interruptible(10000);
+		__touch_softlockup_watchdog();
+		schedule();
+
+		if (kthread_should_stop())
+			break;
 
-		if (this_cpu != check_cpu)
-			continue;
+		if (this_cpu == check_cpu) {
+			if (sysctl_hung_task_timeout_secs)
+				check_hung_uninterruptible_tasks(this_cpu);
+		}
 
-		if (sysctl_hung_task_timeout_secs)
-			check_hung_uninterruptible_tasks(this_cpu);
+		set_current_state(TASK_INTERRUPTIBLE);
 	}
+	__set_current_state(TASK_RUNNING);
 
 	return 0;
 }
@@ -259,13 +274,6 @@ cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
 		wake_up_process(per_cpu(watchdog_task, hotcpu));
 		break;
 #ifdef CONFIG_HOTPLUG_CPU
-	case CPU_UP_CANCELED:
-	case CPU_UP_CANCELED_FROZEN:
-		if (!per_cpu(watchdog_task, hotcpu))
-			break;
-		/* Unbind so it can run.  Fall thru. */
-		kthread_bind(per_cpu(watchdog_task, hotcpu),
-			     any_online_cpu(cpu_online_map));
 	case CPU_DOWN_PREPARE:
 	case CPU_DOWN_PREPARE_FROZEN:
 		if (hotcpu == check_cpu) {
@@ -275,6 +283,14 @@ cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
 			check_cpu = any_online_cpu(temp_cpu_online_map);
 		}
 		break;
+
+	case CPU_UP_CANCELED:
+	case CPU_UP_CANCELED_FROZEN:
+		if (!per_cpu(watchdog_task, hotcpu))
+			break;
+		/* Unbind so it can run.  Fall thru. */
+		kthread_bind(per_cpu(watchdog_task, hotcpu),
+			     any_online_cpu(cpu_online_map));
 	case CPU_DEAD:
 	case CPU_DEAD_FROZEN:
 		p = per_cpu(watchdog_task, hotcpu);