diff options
-rw-r--r-- | arch/arm/mach-at91/at91rm9200_time.c | 7 | ||||
-rw-r--r-- | drivers/clocksource/Kconfig | 1 | ||||
-rw-r--r-- | drivers/clocksource/sh_mtu2.c | 16 | ||||
-rw-r--r-- | drivers/clocksource/sh_tmu.c | 20 | ||||
-rw-r--r-- | kernel/rcu/tree_plugin.h | 4 | ||||
-rw-r--r-- | kernel/time/tick-common.c | 15 | ||||
-rw-r--r-- | kernel/time/tick-sched.c | 25 | ||||
-rw-r--r-- | kernel/time/timekeeping.c | 2 | ||||
-rw-r--r-- | kernel/timer.c | 5 |
9 files changed, 66 insertions, 29 deletions
diff --git a/arch/arm/mach-at91/at91rm9200_time.c b/arch/arm/mach-at91/at91rm9200_time.c index f607deb..bc7b363 100644 --- a/arch/arm/mach-at91/at91rm9200_time.c +++ b/arch/arm/mach-at91/at91rm9200_time.c @@ -174,7 +174,6 @@ clkevt32k_next_event(unsigned long delta, struct clock_event_device *dev) static struct clock_event_device clkevt = { .name = "at91_tick", .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, - .shift = 32, .rating = 150, .set_next_event = clkevt32k_next_event, .set_mode = clkevt32k_mode, @@ -265,11 +264,9 @@ void __init at91rm9200_timer_init(void) at91_st_write(AT91_ST_RTMR, 1); /* Setup timer clockevent, with minimum of two ticks (important!!) */ - clkevt.mult = div_sc(AT91_SLOW_CLOCK, NSEC_PER_SEC, clkevt.shift); - clkevt.max_delta_ns = clockevent_delta2ns(AT91_ST_ALMV, &clkevt); - clkevt.min_delta_ns = clockevent_delta2ns(2, &clkevt) + 1; clkevt.cpumask = cpumask_of(0); - clockevents_register_device(&clkevt); + clockevents_config_and_register(&clkevt, AT91_SLOW_CLOCK, + 2, AT91_ST_ALMV); /* register clocksource */ clocksource_register_hz(&clk32k, AT91_SLOW_CLOCK); diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index bdb953e..5c07a56 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -87,6 +87,7 @@ config ARM_ARCH_TIMER config ARM_ARCH_TIMER_EVTSTREAM bool "Support for ARM architected timer event stream generation" default y if ARM_ARCH_TIMER + depends on ARM_ARCH_TIMER help This option enables support for event stream generation based on the ARM architected timer. It is used for waking up CPUs executing diff --git a/drivers/clocksource/sh_mtu2.c b/drivers/clocksource/sh_mtu2.c index 4aac9ee..3cf1283 100644 --- a/drivers/clocksource/sh_mtu2.c +++ b/drivers/clocksource/sh_mtu2.c @@ -313,8 +313,20 @@ static int sh_mtu2_setup(struct sh_mtu2_priv *p, struct platform_device *pdev) goto err1; } - return sh_mtu2_register(p, (char *)dev_name(&p->pdev->dev), - cfg->clockevent_rating); + ret = clk_prepare(p->clk); + if (ret < 0) + goto err2; + + ret = sh_mtu2_register(p, (char *)dev_name(&p->pdev->dev), + cfg->clockevent_rating); + if (ret < 0) + goto err3; + + return 0; + err3: + clk_unprepare(p->clk); + err2: + clk_put(p->clk); err1: iounmap(p->mapbase); err0: diff --git a/drivers/clocksource/sh_tmu.c b/drivers/clocksource/sh_tmu.c index 78b8dae..63557cd 100644 --- a/drivers/clocksource/sh_tmu.c +++ b/drivers/clocksource/sh_tmu.c @@ -472,12 +472,26 @@ static int sh_tmu_setup(struct sh_tmu_priv *p, struct platform_device *pdev) ret = PTR_ERR(p->clk); goto err1; } + + ret = clk_prepare(p->clk); + if (ret < 0) + goto err2; + p->cs_enabled = false; p->enable_count = 0; - return sh_tmu_register(p, (char *)dev_name(&p->pdev->dev), - cfg->clockevent_rating, - cfg->clocksource_rating); + ret = sh_tmu_register(p, (char *)dev_name(&p->pdev->dev), + cfg->clockevent_rating, + cfg->clocksource_rating); + if (ret < 0) + goto err3; + + return 0; + + err3: + clk_unprepare(p->clk); + err2: + clk_put(p->clk); err1: iounmap(p->mapbase); err0: diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 6abb03d..08a7652 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -1632,7 +1632,7 @@ module_param(rcu_idle_gp_delay, int, 0644); static int rcu_idle_lazy_gp_delay = RCU_IDLE_LAZY_GP_DELAY; module_param(rcu_idle_lazy_gp_delay, int, 0644); -extern int tick_nohz_enabled; +extern int tick_nohz_active; /* * Try to advance callbacks for all flavors of RCU on the current CPU, but @@ -1729,7 +1729,7 @@ static void rcu_prepare_for_idle(int cpu) int tne; /* Handle nohz enablement switches conservatively. */ - tne = ACCESS_ONCE(tick_nohz_enabled); + tne = ACCESS_ONCE(tick_nohz_active); if (tne != rdtp->tick_nohz_enabled_snap) { if (rcu_cpu_has_callbacks(cpu, NULL)) invoke_rcu_core(); /* force nohz to see update. */ diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index 64522ec..162b03a 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -33,6 +33,21 @@ DEFINE_PER_CPU(struct tick_device, tick_cpu_device); */ ktime_t tick_next_period; ktime_t tick_period; + +/* + * tick_do_timer_cpu is a timer core internal variable which holds the CPU NR + * which is responsible for calling do_timer(), i.e. the timekeeping stuff. This + * variable has two functions: + * + * 1) Prevent a thundering herd issue of a gazillion of CPUs trying to grab the + * timekeeping lock all at once. Only the CPU which is assigned to do the + * update is handling it. + * + * 2) Hand off the duty in the NOHZ idle case by setting the value to + * TICK_DO_TIMER_NONE, i.e. a non existing CPU. So the next cpu which looks + * at it will take over and keep the time keeping alive. The handover + * procedure also covers cpu hotplug. + */ int tick_do_timer_cpu __read_mostly = TICK_DO_TIMER_BOOT; /* diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 3612fc7..ea20f7d 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -361,8 +361,8 @@ void __init tick_nohz_init(void) /* * NO HZ enabled ? */ -int tick_nohz_enabled __read_mostly = 1; - +static int tick_nohz_enabled __read_mostly = 1; +int tick_nohz_active __read_mostly; /* * Enable / Disable tickless mode */ @@ -465,7 +465,7 @@ u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time) struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); ktime_t now, idle; - if (!tick_nohz_enabled) + if (!tick_nohz_active) return -1; now = ktime_get(); @@ -506,7 +506,7 @@ u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time) struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); ktime_t now, iowait; - if (!tick_nohz_enabled) + if (!tick_nohz_active) return -1; now = ktime_get(); @@ -711,8 +711,10 @@ static bool can_stop_idle_tick(int cpu, struct tick_sched *ts) return false; } - if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE)) + if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE)) { + ts->sleep_length = (ktime_t) { .tv64 = NSEC_PER_SEC/HZ }; return false; + } if (need_resched()) return false; @@ -799,11 +801,6 @@ void tick_nohz_idle_enter(void) local_irq_disable(); ts = &__get_cpu_var(tick_cpu_sched); - /* - * set ts->inidle unconditionally. even if the system did not - * switch to nohz mode the cpu frequency governers rely on the - * update of the idle time accounting in tick_nohz_start_idle(). - */ ts->inidle = 1; __tick_nohz_idle_enter(ts); @@ -973,7 +970,7 @@ static void tick_nohz_switch_to_nohz(void) struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched); ktime_t next; - if (!tick_nohz_enabled) + if (!tick_nohz_active) return; local_irq_disable(); @@ -981,7 +978,7 @@ static void tick_nohz_switch_to_nohz(void) local_irq_enable(); return; } - + tick_nohz_active = 1; ts->nohz_mode = NOHZ_MODE_LOWRES; /* @@ -1139,8 +1136,10 @@ void tick_setup_sched_timer(void) } #ifdef CONFIG_NO_HZ_COMMON - if (tick_nohz_enabled) + if (tick_nohz_enabled) { ts->nohz_mode = NOHZ_MODE_HIGHRES; + tick_nohz_active = 1; + } #endif } #endif /* HIGH_RES_TIMERS */ diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 3abf534..87b4f00 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -1347,7 +1347,7 @@ static inline void old_vsyscall_fixup(struct timekeeper *tk) tk->xtime_nsec -= remainder; tk->xtime_nsec += 1ULL << tk->shift; tk->ntp_error += remainder << tk->ntp_error_shift; - + tk->ntp_error -= (1ULL << tk->shift) << tk->ntp_error_shift; } #else #define old_vsyscall_fixup(tk) diff --git a/kernel/timer.c b/kernel/timer.c index 6582b82..accfd24 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -1518,9 +1518,8 @@ static int init_timers_cpu(int cpu) /* * The APs use this path later in boot */ - base = kmalloc_node(sizeof(*base), - GFP_KERNEL | __GFP_ZERO, - cpu_to_node(cpu)); + base = kzalloc_node(sizeof(*base), GFP_KERNEL, + cpu_to_node(cpu)); if (!base) return -ENOMEM; |