X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Ftime%2Fclocksource.c;h=dadde5361f32df668877aaa8d5a2e56abb5bb9ff;hb=b72e9ebe7efa5754aa53bbdb0040a2d6eeb34db3;hp=7f60097d443a6258b2044a37b5d23f0d4656aaca;hpb=2a467d5f7d6bdc90c365db167a10022dd8351894;p=linux-2.6

diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 7f60097d44..dadde5361f 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -141,8 +141,16 @@ 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);
 }
@@ -164,7 +172,8 @@ 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)
@@ -185,7 +194,8 @@ 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));
 			}
 		}
 	}
@@ -221,6 +231,18 @@ void clocksource_resume(void)
 	spin_unlock_irqrestore(&clocksource_lock, flags);
 }
 
+/**
+ * clocksource_touch_watchdog - Update watchdog
+ *
+ * Update the watchdog after exception contexts such as kgdb so as not
+ * to incorrectly trip the watchdog.
+ *
+ */
+void clocksource_touch_watchdog(void)
+{
+	clocksource_resume_watchdog();
+}
+
 /**
  * clocksource_get_next - Returns the selected clocksource
  *
@@ -449,10 +471,10 @@ sysfs_show_available_clocksources(struct sys_device *dev, char *buf)
 /*
  * Sysfs setup bits:
  */
-static SYSDEV_ATTR(current_clocksource, 0600, sysfs_show_current_clocksources,
+static SYSDEV_ATTR(current_clocksource, 0644, sysfs_show_current_clocksources,
 		   sysfs_override_clocksource);
 
-static SYSDEV_ATTR(available_clocksource, 0600,
+static SYSDEV_ATTR(available_clocksource, 0444,
 		   sysfs_show_available_clocksources, NULL);
 
 static struct sysdev_class clocksource_sysclass = {