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-rw-r--r--drivers/clocksource/Kconfig1
-rw-r--r--drivers/clocksource/asm9260_timer.c4
-rw-r--r--drivers/clocksource/renesas-ostm.c189
-rw-r--r--drivers/clocksource/timer-of.c6
-rw-r--r--fs/exec.c2
-rw-r--r--fs/proc/array.c2
-rw-r--r--include/linux/hrtimer.h14
-rw-r--r--include/linux/interrupt.h3
-rw-r--r--include/linux/sched.h2
-rw-r--r--kernel/fork.c2
-rw-r--r--kernel/time/hrtimer.c11
-rw-r--r--kernel/time/time.c26
12 files changed, 117 insertions, 145 deletions
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 <linux/of_address.h>
-#include <linux/of_irq.h>
#include <linux/clk.h>
#include <linux/clockchips.h>
#include <linux/interrupt.h>
#include <linux/sched_clock.h>
#include <linux/slab.h>
+#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)
-{
- return container_of(ced, struct ostm_device, ced);
-}
-
-static void ostm_timer_stop(struct ostm_device *ostm)
+static void ostm_timer_stop(struct timer_of *to)
{
- 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(ostm);
+ ostm_timer_stop(to);
- writel(0, ostm->base + OSTM_CMP);
- writeb(CTL_FREERUN, ostm->base + OSTM_CTL);
- writeb(TS, ostm->base + OSTM_TS);
+ 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);
- 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;
-
- 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;
- }
+ struct clock_event_device *ced = &to->clkevt;
- 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;
-
- ostm = kzalloc(sizeof(*ostm), GFP_KERNEL);
- if (!ostm)
- return -ENOMEM;
-
- ostm->base = of_iomap(np, 0);
- if (!ostm->base) {
- pr_err("ostm: failed to remap I/O memory\n");
- goto err;
- }
-
- irq = irq_of_parse_and_map(np, 0);
- if (irq < 0) {
- pr_err("ostm: Failed to get irq\n");
- goto err;
- }
+ struct timer_of *to;
+ int ret;
- 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;
- }
+ to = kzalloc(sizeof(*to), GFP_KERNEL);
+ if (!to)
+ return -ENOMEM;
- ret = clk_prepare_enable(ostm_clk);
- if (ret) {
- pr_err("ostm: Failed to enable clock\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;
}
- 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;