We need some quick way to check if the CPU has stopped its tick. This will be useful to implement the printk tick using the irq work subsystem.
Signed-off-by: Frederic Weisbecker <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Paul Gortmaker <[email protected]> --- include/linux/tick.h | 17 ++++++++++++++++- kernel/time/tick-sched.c | 2 +- 2 files changed, 17 insertions(+), 2 deletions(-) diff --git a/include/linux/tick.h b/include/linux/tick.h index f37fceb..2307dd3 100644 --- a/include/linux/tick.h +++ b/include/linux/tick.h @@ -8,6 +8,8 @@ #include <linux/clockchips.h> #include <linux/irqflags.h> +#include <linux/percpu.h> +#include <linux/hrtimer.h> #ifdef CONFIG_GENERIC_CLOCKEVENTS @@ -122,13 +124,26 @@ static inline int tick_oneshot_mode_active(void) { return 0; } #endif /* !CONFIG_GENERIC_CLOCKEVENTS */ # ifdef CONFIG_NO_HZ +DECLARE_PER_CPU(struct tick_sched, tick_cpu_sched); + +static inline int tick_nohz_tick_stopped(void) +{ + return __this_cpu_read(tick_cpu_sched.tick_stopped); +} + extern void tick_nohz_idle_enter(void); extern void tick_nohz_idle_exit(void); extern void tick_nohz_irq_exit(void); extern ktime_t tick_nohz_get_sleep_length(void); extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time); extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time); -# else + +# else /* !CONFIG_NO_HZ */ +static inline int tick_nohz_tick_stopped(void) +{ + return 0; +} + static inline void tick_nohz_idle_enter(void) { } static inline void tick_nohz_idle_exit(void) { } diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index a402608..9e945aa 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -28,7 +28,7 @@ /* * Per cpu nohz control structure */ -static DEFINE_PER_CPU(struct tick_sched, tick_cpu_sched); +DEFINE_PER_CPU(struct tick_sched, tick_cpu_sched); /* * The time, when the last jiffy update happened. Protected by xtime_lock. -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
