There is only one caller of tick_check_oneshot_change(), i.e. hrtimer_run_pending(). Firstly hrtimer_run_pending() is calling this routine after doing a '!' of its parameter and then tick_check_oneshot_change() is also using it after doing a '!' of its parameter.
It would be more efficient and readable if we can just invert the meaning of this parameter. So, it is hres_enabled instead of allow_nohz now.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- include/linux/tick.h | 6 +++--- kernel/hrtimer.c | 2 +- kernel/time/tick-sched.c | 10 +++++----- 3 files changed, 9 insertions(+), 9 deletions(-)
diff --git a/include/linux/tick.h b/include/linux/tick.h index b8ee6f4..801e844 100644 --- a/include/linux/tick.h +++ b/include/linux/tick.h @@ -120,7 +120,7 @@ extern struct cpumask *tick_get_broadcast_oneshot_mask(void);
# ifdef CONFIG_TICK_ONESHOT extern void tick_clock_notify(void); -extern int tick_check_oneshot_change(int allow_nohz); +extern int tick_check_oneshot_change(int hres_enabled); extern struct tick_sched *tick_get_tick_sched(int cpu); extern void tick_irq_enter(void); extern int tick_oneshot_mode_active(void); @@ -129,7 +129,7 @@ extern int tick_oneshot_mode_active(void); # endif # else static inline void tick_clock_notify(void) { } -static inline int tick_check_oneshot_change(int allow_nohz) { return 0; } +static inline int tick_check_oneshot_change(int hres_enabled) { return 0; } static inline void tick_irq_enter(void) { } static inline int tick_oneshot_mode_active(void) { return 0; } # endif @@ -138,7 +138,7 @@ static inline int tick_oneshot_mode_active(void) { return 0; } static inline void tick_init(void) { } static inline void tick_cancel_sched_timer(int cpu) { } static inline void tick_clock_notify(void) { } -static inline int tick_check_oneshot_change(int allow_nohz) { return 0; } +static inline int tick_check_oneshot_change(int hres_enabled) { return 0; } static inline void tick_irq_enter(void) { } static inline int tick_oneshot_mode_active(void) { return 0; } #endif /* !CONFIG_GENERIC_CLOCKEVENTS */ diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 393f422..bfa7811 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -1457,7 +1457,7 @@ void hrtimer_run_pending(void) * check bit in the tick_oneshot code, otherwise we might * deadlock vs. xtime_lock. */ - if (tick_check_oneshot_change(!hrtimer_is_hres_enabled())) + if (tick_check_oneshot_change(hrtimer_is_hres_enabled())) hrtimer_switch_to_hres(); }
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index c81b6cf..256f4a3 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -1177,11 +1177,11 @@ void tick_oneshot_notify(void) * Check, if a change happened, which makes oneshot possible. * * Called cyclic from the hrtimer softirq (driven by the timer - * softirq) allow_nohz signals, that we can switch into low-res nohz - * mode, because high resolution timers are disabled (either compile - * or runtime). + * softirq). If hres_enabled is non zero, it means we can't switch into low-res + * nohz mode, because high resolution timers are enabled(either compile or + * runtime). */ -int tick_check_oneshot_change(int allow_nohz) +int tick_check_oneshot_change(int hres_enabled) { struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched);
@@ -1194,7 +1194,7 @@ int tick_check_oneshot_change(int allow_nohz) if (!timekeeping_valid_for_hres() || !tick_is_oneshot_available()) return 0;
- if (!allow_nohz) + if (hres_enabled) return 1;
tick_nohz_switch_to_nohz();