locking/static_keys: Add static_key_{en,dis}able() helpers

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / kernel / timer.c

diff --git a/kernel/timer.c b/kernel/timer.c
index 15ffdb3f1948b9468c2c04527beb8190b0d79d45..be22e45dc36f308c47d24c71d4344d900a259c27 100644 (file)
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -149,9 +149,11 @@ static unsigned long round_jiffies_common(unsigned long j, int cpu,
        /* now that we have rounded, subtract the extra skew again */
        j -= cpu * 3;
 
-       if (j <= jiffies) /* rounding ate our timeout entirely; */
-               return original;
-       return j;
+       /*
+        * Make sure j is still in the future. Otherwise return the
+        * unmodified value.
+        */
+       return time_is_after_jiffies(j) ? j : original;
 }
 
 /**
@@ -820,7 +822,7 @@ unsigned long apply_slack(struct timer_list *timer, unsigned long expires)
 
        bit = find_last_bit(&mask, BITS_PER_LONG);
 
-       mask = (1 << bit) - 1;
+       mask = (1UL << bit) - 1;
 
        expires_limit = expires_limit & ~(mask);
 
@@ -921,13 +923,26 @@ EXPORT_SYMBOL(add_timer);
  */
 void add_timer_on(struct timer_list *timer, int cpu)
 {
-       struct tvec_base *base = per_cpu(tvec_bases, cpu);
+       struct tvec_base *new_base = per_cpu(tvec_bases, cpu);
+       struct tvec_base *base;
        unsigned long flags;
 
        timer_stats_timer_set_start_info(timer);
        BUG_ON(timer_pending(timer) || !timer->function);
-       spin_lock_irqsave(&base->lock, flags);
-       timer_set_base(timer, base);
+
+       /*
+        * If @timer was on a different CPU, it should be migrated with the
+        * old base locked to prevent other operations proceeding with the
+        * wrong base locked.  See lock_timer_base().
+        */
+       base = lock_timer_base(timer, &flags);
+       if (base != new_base) {
+               timer_set_base(timer, NULL);
+               spin_unlock(&base->lock);
+               base = new_base;
+               spin_lock(&base->lock);
+               timer_set_base(timer, base);
+       }
        debug_activate(timer, timer->expires);
        internal_add_timer(base, timer);
        /*