X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Ftime%2Fclocksource.c;h=548c436a776bd35b40b7e9143f24a2743246650b;hb=0eccf60bfa9190d1588b2bf07d23d7b9b3a19d9e;hp=cabfa193efb34ea436dcf04618824236a6f8c450;hpb=1077f5a917b7c630231037826b344b2f7f5b903f;p=linux-2.6

diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index cabfa193ef..548c436a77 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -91,7 +91,6 @@ static void clocksource_ratewd(struct clocksource *cs, int64_t delta)
 	       cs->name, delta);
 	cs->flags &= ~(CLOCK_SOURCE_VALID_FOR_HRES | CLOCK_SOURCE_WATCHDOG);
 	clocksource_change_rating(cs, 0);
-	cs->flags &= ~CLOCK_SOURCE_WATCHDOG;
 	list_del(&cs->wd_list);
 }
 
@@ -142,8 +141,13 @@ static void clocksource_watchdog(unsigned long data)
 	}
 
 	if (!list_empty(&watchdog_list)) {
-		__mod_timer(&watchdog_timer,
-			    watchdog_timer.expires + WATCHDOG_INTERVAL);
+		/* Cycle through CPUs to check if the CPUs stay synchronized to
+		 * each other. */
+		int next_cpu = next_cpu(raw_smp_processor_id(), cpu_online_map);
+		if (next_cpu >= NR_CPUS)
+			next_cpu = first_cpu(cpu_online_map);
+		watchdog_timer.expires += WATCHDOG_INTERVAL;
+		add_timer_on(&watchdog_timer, next_cpu);
 	}
 	spin_unlock(&watchdog_lock);
 }
@@ -165,7 +169,7 @@ static void clocksource_check_watchdog(struct clocksource *cs)
 		if (!started && watchdog) {
 			watchdog_last = watchdog->read();
 			watchdog_timer.expires = jiffies + WATCHDOG_INTERVAL;
-			add_timer(&watchdog_timer);
+			add_timer_on(&watchdog_timer, first_cpu(cpu_online_map));
 		}
 	} else {
 		if (cs->flags & CLOCK_SOURCE_IS_CONTINUOUS)
@@ -186,7 +190,8 @@ static void clocksource_check_watchdog(struct clocksource *cs)
 				watchdog_last = watchdog->read();
 				watchdog_timer.expires =
 					jiffies + WATCHDOG_INTERVAL;
-				add_timer(&watchdog_timer);
+				add_timer_on(&watchdog_timer,
+						first_cpu(cpu_online_map));
 			}
 		}
 	}
@@ -331,6 +336,21 @@ void clocksource_change_rating(struct clocksource *cs, int rating)
 	spin_unlock_irqrestore(&clocksource_lock, flags);
 }
 
+/**
+ * clocksource_unregister - remove a registered clocksource
+ */
+void clocksource_unregister(struct clocksource *cs)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&clocksource_lock, flags);
+	list_del(&cs->list);
+	if (clocksource_override == cs)
+		clocksource_override = NULL;
+	next_clocksource = select_clocksource();
+	spin_unlock_irqrestore(&clocksource_lock, flags);
+}
+
 #ifdef CONFIG_SYSFS
 /**
  * sysfs_show_current_clocksources - sysfs interface for current clocksource
@@ -342,15 +362,13 @@ void clocksource_change_rating(struct clocksource *cs, int rating)
 static ssize_t
 sysfs_show_current_clocksources(struct sys_device *dev, char *buf)
 {
-	char *curr = buf;
+	ssize_t count = 0;
 
 	spin_lock_irq(&clocksource_lock);
-	curr += sprintf(curr, "%s ", curr_clocksource->name);
+	count = snprintf(buf, PAGE_SIZE, "%s\n", curr_clocksource->name);
 	spin_unlock_irq(&clocksource_lock);
 
-	curr += sprintf(curr, "\n");
-
-	return curr - buf;
+	return count;
 }
 
 /**
@@ -418,17 +436,20 @@ static ssize_t
 sysfs_show_available_clocksources(struct sys_device *dev, char *buf)
 {
 	struct clocksource *src;
-	char *curr = buf;
+	ssize_t count = 0;
 
 	spin_lock_irq(&clocksource_lock);
 	list_for_each_entry(src, &clocksource_list, list) {
-		curr += sprintf(curr, "%s ", src->name);
+		count += snprintf(buf + count,
+				  max((ssize_t)PAGE_SIZE - count, (ssize_t)0),
+				  "%s ", src->name);
 	}
 	spin_unlock_irq(&clocksource_lock);
 
-	curr += sprintf(curr, "\n");
+	count += snprintf(buf + count,
+			  max((ssize_t)PAGE_SIZE - count, (ssize_t)0), "\n");
 
-	return curr - buf;
+	return count;
 }
 
 /*