From: "Richard Cochran (linutronix GmbH)" <richardcochran@gmail.com>
The logic to get the time of the last jiffies update will be needed by
the timer pull model as well.
Move the code into a global function in anticipation of the new caller.
No functional change.
Signed-off-by: Richard Cochran (linutronix GmbH) <richardcochran@gmail.com>
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
---
kernel/time/tick-internal.h | 1 +
kernel/time/tick-sched.c | 18 +++++++++++++++---
2 files changed, 16 insertions(+), 3 deletions(-)
@@ -158,6 +158,7 @@ static inline void tick_nohz_init(void) { }
#ifdef CONFIG_NO_HZ_COMMON
extern unsigned long tick_nohz_active;
extern void timers_update_nohz(void);
+extern u64 get_jiffies_update(unsigned long *basej);
# ifdef CONFIG_SMP
extern struct static_key_false timers_migration_enabled;
extern void fetch_next_timer_interrupt_remote(unsigned long basej, u64 basem,
@@ -799,18 +799,30 @@ static inline bool local_timer_softirq_pending(void)
return local_softirq_pending() & BIT(TIMER_SOFTIRQ);
}
-static ktime_t tick_nohz_next_event(struct tick_sched *ts, int cpu)
+/*
+ * Read jiffies and the time when jiffies were updated last
+ */
+u64 get_jiffies_update(unsigned long *basej)
{
- u64 basemono, next_tick, delta, expires;
unsigned long basejiff;
unsigned int seq;
+ u64 basemono;
- /* Read jiffies and the time when jiffies were updated last */
do {
seq = read_seqcount_begin(&jiffies_seq);
basemono = last_jiffies_update;
basejiff = jiffies;
} while (read_seqcount_retry(&jiffies_seq, seq));
+ *basej = basejiff;
+ return basemono;
+}
+
+static ktime_t tick_nohz_next_event(struct tick_sched *ts, int cpu)
+{
+ u64 basemono, next_tick, delta, expires;
+ unsigned long basejiff;
+
+ basemono = get_jiffies_update(&basejiff);
ts->last_jiffies = basejiff;
ts->timer_expires_base = basemono;