[tip:,timers/core] timers: Introduce function to check timer base is_idle flag
Commit Message
The following commit has been merged into the timers/core branch of tip:
Commit-ID: 57e95a5c4117dc6a67dc416d82079c02dab7e983
Gitweb: https://git.kernel.org/tip/57e95a5c4117dc6a67dc416d82079c02dab7e983
Author: Anna-Maria Behnsen <anna-maria@linutronix.de>
AuthorDate: Wed, 21 Feb 2024 10:05:45 +01:00
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Thu, 22 Feb 2024 17:52:32 +01:00
timers: Introduce function to check timer base is_idle flag
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@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20240221090548.36600-18-anna-maria@linutronix.de
---
kernel/time/tick-internal.h | 1 +
kernel/time/timer.c | 10 ++++++++++
2 files changed, 11 insertions(+)
@@ -165,6 +165,7 @@ 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) { }
@@ -2159,6 +2159,16 @@ void timer_lock_remote_bases(unsigned int cpu)
raw_spin_lock(&base_local->lock);
raw_spin_lock_nested(&base_global->lock, SINGLE_DEPTH_NESTING);
}
+
+/**
+ * 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);
+}
# endif /* CONFIG_SMP */
static inline u64 __get_next_timer_interrupt(unsigned long basej, u64 basem,