[PATCH 4/9] nohz: Add API to check tick state
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 Acked-by: Steven Rostedt Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Andrew Morton Cc: Paul Gortmaker --- 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 #include +#include +#include #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 majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH 4/9] nohz: Add API to check tick state
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 Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Andrew Morton Cc: Steven Rostedt Cc: Paul Gortmaker --- 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 #include +#include +#include #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 majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/