1 files changed, 11 insertions, 2 deletions

diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index cb02324bdb88..b711ffcb106c 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -20,6 +20,7 @@
 #include <linux/profile.h>
 #include <linux/sched.h>
 #include <linux/tick.h>
+#include <linux/module.h>
 
 #include <asm/irq_regs.h>
 
@@ -190,9 +191,17 @@ u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time)
 {
         struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
 
-        *last_update_time = ktime_to_us(ts->idle_lastupdate);
+        if (!tick_nohz_enabled)
+                return -1;
+
+        if (ts->idle_active)
+                *last_update_time = ktime_to_us(ts->idle_lastupdate);
+        else
+                *last_update_time = ktime_to_us(ktime_get());
+
         return ktime_to_us(ts->idle_sleeptime);
 }
+EXPORT_SYMBOL_GPL(get_cpu_idle_time_us);
 
 /**
  * tick_nohz_stop_sched_tick - stop the idle tick from the idle task
@@ -261,7 +270,7 @@ void tick_nohz_stop_sched_tick(int inidle)
         next_jiffies = get_next_timer_interrupt(last_jiffies);
         delta_jiffies = next_jiffies - last_jiffies;
 
-        if (rcu_needs_cpu(cpu))
+        if (rcu_needs_cpu(cpu) || printk_needs_cpu(cpu))
                 delta_jiffies = 1;
         /*
          * Do not stop the tick, if we are only one off