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Diffstat (limited to 'kernel')
-rw-r--r--kernel/time/timer.c21
1 files changed, 18 insertions, 3 deletions
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 77e21e98ec32..96d802e9769e 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -204,6 +204,7 @@ struct timer_base {
unsigned long clk;
unsigned long next_expiry;
unsigned int cpu;
+ bool next_expiry_recalc;
bool is_idle;
DECLARE_BITMAP(pending_map, WHEEL_SIZE);
struct hlist_head vectors[WHEEL_SIZE];
@@ -593,6 +594,7 @@ static void enqueue_timer(struct timer_base *base, struct timer_list *timer,
* can reevaluate the wheel:
*/
base->next_expiry = bucket_expiry;
+ base->next_expiry_recalc = false;
trigger_dyntick_cpu(base, timer);
}
}
@@ -836,8 +838,10 @@ static int detach_if_pending(struct timer_list *timer, struct timer_base *base,
if (!timer_pending(timer))
return 0;
- if (hlist_is_singular_node(&timer->entry, base->vectors + idx))
+ if (hlist_is_singular_node(&timer->entry, base->vectors + idx)) {
__clear_bit(idx, base->pending_map);
+ base->next_expiry_recalc = true;
+ }
detach_timer(timer, clear_pending);
return 1;
@@ -1571,6 +1575,9 @@ static unsigned long __next_timer_interrupt(struct timer_base *base)
clk >>= LVL_CLK_SHIFT;
clk += adj;
}
+
+ base->next_expiry_recalc = false;
+
return next;
}
@@ -1631,9 +1638,11 @@ u64 get_next_timer_interrupt(unsigned long basej, u64 basem)
return expires;
raw_spin_lock(&base->lock);
- nextevt = __next_timer_interrupt(base);
+ if (base->next_expiry_recalc)
+ base->next_expiry = __next_timer_interrupt(base);
+ nextevt = base->next_expiry;
is_max_delta = (nextevt == base->clk + NEXT_TIMER_MAX_DELTA);
- base->next_expiry = nextevt;
+
/*
* We have a fresh next event. Check whether we can forward the
* base. We can only do that when @basej is past base->clk
@@ -1725,6 +1734,12 @@ static inline void __run_timers(struct timer_base *base)
while (time_after_eq(jiffies, base->clk) &&
time_after_eq(jiffies, base->next_expiry)) {
levels = collect_expired_timers(base, heads);
+ /*
+ * The only possible reason for not finding any expired
+ * timer at this clk is that all matching timers have been
+ * dequeued.
+ */
+ WARN_ON_ONCE(!levels && !base->next_expiry_recalc);
base->clk++;
base->next_expiry = __next_timer_interrupt(base);