[PATCH v9 29/32] timers: Introduce function to check timer base is_idle flag

[Anna-Maria Behnsen]

To prepare for the conversion of the NOHZ timer placement to a pull at
expiry time model it's required to have a function that returns the value
of the is_idle flag of the timer base to keep the hierarchy states during
online in sync with timer base state.

No functional change.

Signed-off-by: Anna-Maria Behnsen <anna-maria@xxxxxxxxxxxxx>
---
v9: new in v9
---
 kernel/time/tick-internal.h |  1 +
 kernel/time/timer.c         | 10 ++++++++++
 2 files changed, 11 insertions(+)

diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h
index e0e58dd18919..2d1a44850c20 100644
--- a/kernel/time/tick-internal.h
+++ b/kernel/time/tick-internal.h
@@ -166,6 +166,7 @@ extern void fetch_next_timer_interrupt_remote(unsigned long basej, u64 basem,
 					      unsigned int cpu);
 extern void timer_lock_remote_bases(unsigned int cpu);
 extern void timer_unlock_remote_bases(unsigned int cpu);
+extern bool timer_base_is_idle(void);
 # endif
 #else /* CONFIG_NO_HZ_COMMON */
 static inline void timers_update_nohz(void) { }
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index a797603dfd49..b6c9ac0c3712 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -2201,6 +2201,16 @@ u64 timer_base_try_to_set_idle(unsigned long basej, u64 basem, bool *idle)
 	return __get_next_timer_interrupt(basej, basem, idle);
 }
 
+/**
+ * timer_base_is_idle() - Return whether timer base is set idle
+ *
+ * Returns value of local timer base is_idle value.
+ */
+bool timer_base_is_idle(void)
+{
+	return __this_cpu_read(timer_bases[BASE_LOCAL].is_idle);
+}
+
 /**
  * timer_clear_idle - Clear the idle state of the timer base
  *
-- 
2.39.2