Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  timers: Consider slack value in mod_timer()
  clockevents: Handle empty cpumask gracefully

diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index c027d4f..e4c699d 100644 (file)
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -182,7 +182,10 @@ void clockevents_register_device(struct clock_event_device *dev)
        unsigned long flags;
 
        BUG_ON(dev->mode != CLOCK_EVT_MODE_UNUSED);
-       BUG_ON(!dev->cpumask);
+       if (!dev->cpumask) {
+               WARN_ON(num_possible_cpus() > 1);
+               dev->cpumask = cpumask_of(smp_processor_id());
+       }
 
        raw_spin_lock_irqsave(&clockevents_lock, flags);
 

diff --git a/kernel/timer.c b/kernel/timer.c
index fd61986..8cff361 100644 (file)
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -749,16 +749,15 @@ unsigned long apply_slack(struct timer_list *timer, unsigned long expires)
        unsigned long expires_limit, mask;
        int bit;
 
-       expires_limit = expires;
-
        if (timer->slack >= 0) {
                expires_limit = expires + timer->slack;
        } else {
-               unsigned long now = jiffies;
+               long delta = expires - jiffies;
+
+               if (delta < 256)
+                       return expires;
 
-               /* No slack, if already expired else auto slack 0.4% */
-               if (time_after(expires, now))
-                       expires_limit = expires + (expires - now)/256;
+               expires_limit = expires + delta / 256;
        }
        mask = expires ^ expires_limit;
        if (mask == 0)
@@ -795,6 +794,8 @@ unsigned long apply_slack(struct timer_list *timer, unsigned long expires)
  */
 int mod_timer(struct timer_list *timer, unsigned long expires)
 {
+       expires = apply_slack(timer, expires);
+
        /*
         * This is a common optimization triggered by the
         * networking code - if the timer is re-modified
@@ -803,8 +804,6 @@ int mod_timer(struct timer_list *timer, unsigned long expires)
        if (timer_pending(timer) && timer->expires == expires)
                return 1;
 
-       expires = apply_slack(timer, expires);
-
        return __mod_timer(timer, expires, false, TIMER_NOT_PINNED);
 }
 EXPORT_SYMBOL(mod_timer);