diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index f35a53ce8988..5fdd76cb1768 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -528,6 +528,7 @@ config SH_TIMER_MTU2 config RENESAS_OSTM bool "Renesas OSTM timer driver" if COMPILE_TEST select CLKSRC_MMIO + select TIMER_OF help Enables the support for the Renesas OSTM. diff --git a/drivers/clocksource/asm9260_timer.c b/drivers/clocksource/asm9260_timer.c index 9f09a59161e7..5b39d3701fa3 100644 --- a/drivers/clocksource/asm9260_timer.c +++ b/drivers/clocksource/asm9260_timer.c @@ -194,6 +194,10 @@ static int __init asm9260_timer_init(struct device_node *np) } clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + pr_err("Failed to get clk!\n"); + return PTR_ERR(clk); + } ret = clk_prepare_enable(clk); if (ret) { diff --git a/drivers/clocksource/renesas-ostm.c b/drivers/clocksource/renesas-ostm.c index 37c39b901bb1..3d06ba66008c 100644 --- a/drivers/clocksource/renesas-ostm.c +++ b/drivers/clocksource/renesas-ostm.c @@ -6,14 +6,14 @@ * Copyright (C) 2017 Chris Brandt */ -#include -#include #include #include #include #include #include +#include "timer-of.h" + /* * The OSTM contains independent channels. * The first OSTM channel probed will be set up as a free running @@ -24,12 +24,6 @@ * driven clock event. */ -struct ostm_device { - void __iomem *base; - unsigned long ticks_per_jiffy; - struct clock_event_device ced; -}; - static void __iomem *system_clock; /* For sched_clock() */ /* OSTM REGISTERS */ @@ -47,41 +41,32 @@ static void __iomem *system_clock; /* For sched_clock() */ #define CTL_ONESHOT 0x02 #define CTL_FREERUN 0x02 -static struct ostm_device *ced_to_ostm(struct clock_event_device *ced) +static void ostm_timer_stop(struct timer_of *to) { - return container_of(ced, struct ostm_device, ced); -} - -static void ostm_timer_stop(struct ostm_device *ostm) -{ - if (readb(ostm->base + OSTM_TE) & TE) { - writeb(TT, ostm->base + OSTM_TT); + if (readb(timer_of_base(to) + OSTM_TE) & TE) { + writeb(TT, timer_of_base(to) + OSTM_TT); /* * Read back the register simply to confirm the write operation * has completed since I/O writes can sometimes get queued by * the bus architecture. */ - while (readb(ostm->base + OSTM_TE) & TE) + while (readb(timer_of_base(to) + OSTM_TE) & TE) ; } } -static int __init ostm_init_clksrc(struct ostm_device *ostm, unsigned long rate) +static int __init ostm_init_clksrc(struct timer_of *to) { - /* - * irq not used (clock sources don't use interrupts) - */ + ostm_timer_stop(to); - ostm_timer_stop(ostm); + writel(0, timer_of_base(to) + OSTM_CMP); + writeb(CTL_FREERUN, timer_of_base(to) + OSTM_CTL); + writeb(TS, timer_of_base(to) + OSTM_TS); - writel(0, ostm->base + OSTM_CMP); - writeb(CTL_FREERUN, ostm->base + OSTM_CTL); - writeb(TS, ostm->base + OSTM_TS); - - return clocksource_mmio_init(ostm->base + OSTM_CNT, - "ostm", rate, - 300, 32, clocksource_mmio_readl_up); + return clocksource_mmio_init(timer_of_base(to) + OSTM_CNT, + to->np->full_name, timer_of_rate(to), 300, + 32, clocksource_mmio_readl_up); } static u64 notrace ostm_read_sched_clock(void) @@ -89,87 +74,75 @@ static u64 notrace ostm_read_sched_clock(void) return readl(system_clock); } -static void __init ostm_init_sched_clock(struct ostm_device *ostm, - unsigned long rate) +static void __init ostm_init_sched_clock(struct timer_of *to) { - system_clock = ostm->base + OSTM_CNT; - sched_clock_register(ostm_read_sched_clock, 32, rate); + system_clock = timer_of_base(to) + OSTM_CNT; + sched_clock_register(ostm_read_sched_clock, 32, timer_of_rate(to)); } static int ostm_clock_event_next(unsigned long delta, - struct clock_event_device *ced) + struct clock_event_device *ced) { - struct ostm_device *ostm = ced_to_ostm(ced); + struct timer_of *to = to_timer_of(ced); - ostm_timer_stop(ostm); + ostm_timer_stop(to); - writel(delta, ostm->base + OSTM_CMP); - writeb(CTL_ONESHOT, ostm->base + OSTM_CTL); - writeb(TS, ostm->base + OSTM_TS); + writel(delta, timer_of_base(to) + OSTM_CMP); + writeb(CTL_ONESHOT, timer_of_base(to) + OSTM_CTL); + writeb(TS, timer_of_base(to) + OSTM_TS); return 0; } static int ostm_shutdown(struct clock_event_device *ced) { - struct ostm_device *ostm = ced_to_ostm(ced); + struct timer_of *to = to_timer_of(ced); - ostm_timer_stop(ostm); + ostm_timer_stop(to); return 0; } static int ostm_set_periodic(struct clock_event_device *ced) { - struct ostm_device *ostm = ced_to_ostm(ced); + struct timer_of *to = to_timer_of(ced); if (clockevent_state_oneshot(ced) || clockevent_state_periodic(ced)) - ostm_timer_stop(ostm); + ostm_timer_stop(to); - writel(ostm->ticks_per_jiffy - 1, ostm->base + OSTM_CMP); - writeb(CTL_PERIODIC, ostm->base + OSTM_CTL); - writeb(TS, ostm->base + OSTM_TS); + writel(timer_of_period(to) - 1, timer_of_base(to) + OSTM_CMP); + writeb(CTL_PERIODIC, timer_of_base(to) + OSTM_CTL); + writeb(TS, timer_of_base(to) + OSTM_TS); return 0; } static int ostm_set_oneshot(struct clock_event_device *ced) { - struct ostm_device *ostm = ced_to_ostm(ced); + struct timer_of *to = to_timer_of(ced); - ostm_timer_stop(ostm); + ostm_timer_stop(to); return 0; } static irqreturn_t ostm_timer_interrupt(int irq, void *dev_id) { - struct ostm_device *ostm = dev_id; + struct clock_event_device *ced = dev_id; - if (clockevent_state_oneshot(&ostm->ced)) - ostm_timer_stop(ostm); + if (clockevent_state_oneshot(ced)) + ostm_timer_stop(to_timer_of(ced)); /* notify clockevent layer */ - if (ostm->ced.event_handler) - ostm->ced.event_handler(&ostm->ced); + if (ced->event_handler) + ced->event_handler(ced); return IRQ_HANDLED; } -static int __init ostm_init_clkevt(struct ostm_device *ostm, int irq, - unsigned long rate) +static int __init ostm_init_clkevt(struct timer_of *to) { - struct clock_event_device *ced = &ostm->ced; - int ret = -ENXIO; + struct clock_event_device *ced = &to->clkevt; - ret = request_irq(irq, ostm_timer_interrupt, - IRQF_TIMER | IRQF_IRQPOLL, - "ostm", ostm); - if (ret) { - pr_err("ostm: failed to request irq\n"); - return ret; - } - - ced->name = "ostm"; ced->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC; ced->set_state_shutdown = ostm_shutdown; ced->set_state_periodic = ostm_set_periodic; @@ -178,79 +151,61 @@ static int __init ostm_init_clkevt(struct ostm_device *ostm, int irq, ced->shift = 32; ced->rating = 300; ced->cpumask = cpumask_of(0); - clockevents_config_and_register(ced, rate, 0xf, 0xffffffff); + clockevents_config_and_register(ced, timer_of_rate(to), 0xf, + 0xffffffff); return 0; } static int __init ostm_init(struct device_node *np) { - struct ostm_device *ostm; - int ret = -EFAULT; - struct clk *ostm_clk = NULL; - int irq; - unsigned long rate; + struct timer_of *to; + int ret; - ostm = kzalloc(sizeof(*ostm), GFP_KERNEL); - if (!ostm) + to = kzalloc(sizeof(*to), GFP_KERNEL); + if (!to) return -ENOMEM; - ostm->base = of_iomap(np, 0); - if (!ostm->base) { - pr_err("ostm: failed to remap I/O memory\n"); - goto err; + to->flags = TIMER_OF_BASE | TIMER_OF_CLOCK; + if (system_clock) { + /* + * clock sources don't use interrupts, clock events do + */ + to->flags |= TIMER_OF_IRQ; + to->of_irq.flags = IRQF_TIMER | IRQF_IRQPOLL; + to->of_irq.handler = ostm_timer_interrupt; } - irq = irq_of_parse_and_map(np, 0); - if (irq < 0) { - pr_err("ostm: Failed to get irq\n"); - goto err; - } - - ostm_clk = of_clk_get(np, 0); - if (IS_ERR(ostm_clk)) { - pr_err("ostm: Failed to get clock\n"); - ostm_clk = NULL; - goto err; - } - - ret = clk_prepare_enable(ostm_clk); - if (ret) { - pr_err("ostm: Failed to enable clock\n"); - goto err; - } - - rate = clk_get_rate(ostm_clk); - ostm->ticks_per_jiffy = DIV_ROUND_CLOSEST(rate, HZ); + ret = timer_of_init(np, to); + if (ret) + goto err_free; /* * First probed device will be used as system clocksource. Any * additional devices will be used as clock events. */ if (!system_clock) { - ret = ostm_init_clksrc(ostm, rate); - - if (!ret) { - ostm_init_sched_clock(ostm, rate); - pr_info("ostm: used for clocksource\n"); - } + ret = ostm_init_clksrc(to); + if (ret) + goto err_cleanup; + ostm_init_sched_clock(to); + pr_info("%pOF: used for clocksource\n", np); } else { - ret = ostm_init_clkevt(ostm, irq, rate); + ret = ostm_init_clkevt(to); + if (ret) + goto err_cleanup; - if (!ret) - pr_info("ostm: used for clock events\n"); - } - -err: - if (ret) { - clk_disable_unprepare(ostm_clk); - iounmap(ostm->base); - kfree(ostm); - return ret; + pr_info("%pOF: used for clock events\n", np); } return 0; + +err_cleanup: + timer_of_cleanup(to); +err_free: + kfree(to); + return ret; } TIMER_OF_DECLARE(ostm, "renesas,ostm", ostm_init); diff --git a/drivers/clocksource/timer-of.c b/drivers/clocksource/timer-of.c index 11ff701ff4bb..572da477c6d3 100644 --- a/drivers/clocksource/timer-of.c +++ b/drivers/clocksource/timer-of.c @@ -57,8 +57,8 @@ static __init int timer_of_irq_init(struct device_node *np, if (of_irq->name) { of_irq->irq = ret = of_irq_get_byname(np, of_irq->name); if (ret < 0) { - pr_err("Failed to get interrupt %s for %s\n", - of_irq->name, np->full_name); + pr_err("Failed to get interrupt %s for %pOF\n", + of_irq->name, np); return ret; } } else { @@ -192,7 +192,7 @@ int __init timer_of_init(struct device_node *np, struct timer_of *to) } if (!to->clkevt.name) - to->clkevt.name = np->name; + to->clkevt.name = np->full_name; to->np = np; diff --git a/fs/exec.c b/fs/exec.c index a504ed68621d..74d88dab98dd 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1131,7 +1131,7 @@ static int de_thread(struct task_struct *tsk) * also take its birthdate (always earlier than our own). */ tsk->start_time = leader->start_time; - tsk->real_start_time = leader->real_start_time; + tsk->start_boottime = leader->start_boottime; BUG_ON(!same_thread_group(leader, tsk)); BUG_ON(has_group_leader_pid(tsk)); diff --git a/fs/proc/array.c b/fs/proc/array.c index 46dcb6f0eccf..5efaf3708ec6 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -533,7 +533,7 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns, nice = task_nice(task); /* convert nsec -> ticks */ - start_time = nsec_to_clock_t(task->real_start_time); + start_time = nsec_to_clock_t(task->start_boottime); seq_put_decimal_ull(m, "", pid_nr_ns(pid, ns)); seq_puts(m, " ("); diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h index 1b9a51a1bccb..1f98b52118f0 100644 --- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -456,12 +456,18 @@ extern u64 hrtimer_next_event_without(const struct hrtimer *exclude); extern bool hrtimer_active(const struct hrtimer *timer); -/* - * Helper function to check, whether the timer is on one of the queues +/** + * hrtimer_is_queued = check, whether the timer is on one of the queues + * @timer: Timer to check + * + * Returns: True if the timer is queued, false otherwise + * + * The function can be used lockless, but it gives only a current snapshot. */ -static inline int hrtimer_is_queued(struct hrtimer *timer) +static inline bool hrtimer_is_queued(struct hrtimer *timer) { - return timer->state & HRTIMER_STATE_ENQUEUED; + /* The READ_ONCE pairs with the update functions of timer->state */ + return !!(READ_ONCE(timer->state) & HRTIMER_STATE_ENQUEUED); } /* diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index ba873ec7e09d..c5fe60ec6b84 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -533,8 +533,7 @@ enum IRQ_POLL_SOFTIRQ, TASKLET_SOFTIRQ, SCHED_SOFTIRQ, - HRTIMER_SOFTIRQ, /* Unused, but kept as tools rely on the - numbering. Sigh! */ + HRTIMER_SOFTIRQ, RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */ NR_SOFTIRQS diff --git a/include/linux/sched.h b/include/linux/sched.h index 07e68d9f5dc4..0cd97d9dd021 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -862,7 +862,7 @@ struct task_struct { u64 start_time; /* Boot based time in nsecs: */ - u64 real_start_time; + u64 start_boottime; /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */ unsigned long min_flt; diff --git a/kernel/fork.c b/kernel/fork.c index 21c6c1e29b98..2508a4f238a3 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -2185,7 +2185,7 @@ static __latent_entropy struct task_struct *copy_process( */ p->start_time = ktime_get_ns(); - p->real_start_time = ktime_get_boottime_ns(); + p->start_boottime = ktime_get_boottime_ns(); /* * Make it visible to the rest of the system, but dont wake it up yet. diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 9e20873148c6..8de90ea31280 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -966,7 +966,8 @@ static int enqueue_hrtimer(struct hrtimer *timer, base->cpu_base->active_bases |= 1 << base->index; - timer->state = HRTIMER_STATE_ENQUEUED; + /* Pairs with the lockless read in hrtimer_is_queued() */ + WRITE_ONCE(timer->state, HRTIMER_STATE_ENQUEUED); return timerqueue_add(&base->active, &timer->node); } @@ -988,7 +989,8 @@ static void __remove_hrtimer(struct hrtimer *timer, struct hrtimer_cpu_base *cpu_base = base->cpu_base; u8 state = timer->state; - timer->state = newstate; + /* Pairs with the lockless read in hrtimer_is_queued() */ + WRITE_ONCE(timer->state, newstate); if (!(state & HRTIMER_STATE_ENQUEUED)) return; @@ -1013,8 +1015,9 @@ static void __remove_hrtimer(struct hrtimer *timer, static inline int remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base, bool restart) { - if (hrtimer_is_queued(timer)) { - u8 state = timer->state; + u8 state = timer->state; + + if (state & HRTIMER_STATE_ENQUEUED) { int reprogram; /* diff --git a/kernel/time/time.c b/kernel/time/time.c index 58e312e7380f..704ccd9451b0 100644 --- a/kernel/time/time.c +++ b/kernel/time/time.c @@ -179,7 +179,7 @@ int do_sys_settimeofday64(const struct timespec64 *tv, const struct timezone *tz return error; if (tz) { - /* Verify we're witin the +-15 hrs range */ + /* Verify we're within the +-15 hrs range */ if (tz->tz_minuteswest > 15*60 || tz->tz_minuteswest < -15*60) return -EINVAL; @@ -548,18 +548,21 @@ EXPORT_SYMBOL(set_normalized_timespec64); */ struct timespec64 ns_to_timespec64(const s64 nsec) { - struct timespec64 ts; + struct timespec64 ts = { 0, 0 }; s32 rem; - if (!nsec) - return (struct timespec64) {0, 0}; - - ts.tv_sec = div_s64_rem(nsec, NSEC_PER_SEC, &rem); - if (unlikely(rem < 0)) { - ts.tv_sec--; - rem += NSEC_PER_SEC; + if (likely(nsec > 0)) { + ts.tv_sec = div_u64_rem(nsec, NSEC_PER_SEC, &rem); + ts.tv_nsec = rem; + } else if (nsec < 0) { + /* + * With negative times, tv_sec points to the earlier + * second, and tv_nsec counts the nanoseconds since + * then, so tv_nsec is always a positive number. + */ + ts.tv_sec = -div_u64_rem(-nsec - 1, NSEC_PER_SEC, &rem) - 1; + ts.tv_nsec = NSEC_PER_SEC - rem - 1; } - ts.tv_nsec = rem; return ts; } @@ -878,10 +881,11 @@ int get_timespec64(struct timespec64 *ts, ts->tv_sec = kts.tv_sec; - /* Zero out the padding for 32 bit systems or in compat mode */ + /* Zero out the padding in compat mode */ if (in_compat_syscall()) kts.tv_nsec &= 0xFFFFFFFFUL; + /* In 32-bit mode, this drops the padding */ ts->tv_nsec = kts.tv_nsec; return 0;