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-rw-r--r--kernel/time/alarmtimer.c28
-rw-r--r--kernel/time/clocksource.c11
-rw-r--r--kernel/time/hrtimer.c11
-rw-r--r--kernel/time/posix-clock.c31
-rw-r--r--kernel/time/sched_clock.c9
-rw-r--r--kernel/time/tick-sched.c14
-rw-r--r--kernel/time/time.c3
-rw-r--r--kernel/time/timekeeping.c2
-rw-r--r--kernel/time/timer.c29
9 files changed, 84 insertions, 54 deletions
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index bfe0e0656f02..15f20dd30bd8 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -88,6 +88,8 @@ static int alarmtimer_rtc_add_device(struct device *dev,
unsigned long flags;
struct rtc_device *rtc = to_rtc_device(dev);
struct wakeup_source *__ws;
+ struct platform_device *pdev;
+ int ret = 0;
if (rtcdev)
return -EBUSY;
@@ -98,12 +100,14 @@ static int alarmtimer_rtc_add_device(struct device *dev,
return -1;
__ws = wakeup_source_register("alarmtimer");
+ pdev = platform_device_register_data(dev, "alarmtimer",
+ PLATFORM_DEVID_AUTO, NULL, 0);
spin_lock_irqsave(&rtcdev_lock, flags);
- if (!rtcdev) {
+ if (__ws && !IS_ERR(pdev) && !rtcdev) {
if (!try_module_get(rtc->owner)) {
- spin_unlock_irqrestore(&rtcdev_lock, flags);
- return -1;
+ ret = -1;
+ goto unlock;
}
rtcdev = rtc;
@@ -111,12 +115,17 @@ static int alarmtimer_rtc_add_device(struct device *dev,
get_device(dev);
ws = __ws;
__ws = NULL;
+ pdev = NULL;
+ } else {
+ ret = -1;
}
+unlock:
spin_unlock_irqrestore(&rtcdev_lock, flags);
+ platform_device_unregister(pdev);
wakeup_source_unregister(__ws);
- return 0;
+ return ret;
}
static inline void alarmtimer_rtc_timer_init(void)
@@ -861,8 +870,7 @@ static struct platform_driver alarmtimer_driver = {
*/
static int __init alarmtimer_init(void)
{
- struct platform_device *pdev;
- int error = 0;
+ int error;
int i;
alarmtimer_rtc_timer_init();
@@ -885,15 +893,7 @@ static int __init alarmtimer_init(void)
if (error)
goto out_if;
- pdev = platform_device_register_simple("alarmtimer", -1, NULL, 0);
- if (IS_ERR(pdev)) {
- error = PTR_ERR(pdev);
- goto out_drv;
- }
return 0;
-
-out_drv:
- platform_driver_unregister(&alarmtimer_driver);
out_if:
alarmtimer_rtc_interface_remove();
return error;
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 3bcc19ceb073..cf74160e79c7 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -293,8 +293,15 @@ static void clocksource_watchdog(struct timer_list *unused)
next_cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask);
if (next_cpu >= nr_cpu_ids)
next_cpu = cpumask_first(cpu_online_mask);
- watchdog_timer.expires += WATCHDOG_INTERVAL;
- add_timer_on(&watchdog_timer, next_cpu);
+
+ /*
+ * Arm timer if not already pending: could race with concurrent
+ * pair clocksource_stop_watchdog() clocksource_start_watchdog().
+ */
+ if (!timer_pending(&watchdog_timer)) {
+ watchdog_timer.expires += WATCHDOG_INTERVAL;
+ add_timer_on(&watchdog_timer, next_cpu);
+ }
out:
spin_unlock(&watchdog_lock);
}
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 41dfff23c1f9..5f15dad63bce 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -946,7 +946,8 @@ 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);
}
@@ -968,7 +969,8 @@ 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;
@@ -993,8 +995,9 @@ 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/posix-clock.c b/kernel/time/posix-clock.c
index ec960bb939fd..200fb2d3be99 100644
--- a/kernel/time/posix-clock.c
+++ b/kernel/time/posix-clock.c
@@ -14,8 +14,6 @@
#include "posix-timers.h"
-static void delete_clock(struct kref *kref);
-
/*
* Returns NULL if the posix_clock instance attached to 'fp' is old and stale.
*/
@@ -125,7 +123,7 @@ static int posix_clock_open(struct inode *inode, struct file *fp)
err = 0;
if (!err) {
- kref_get(&clk->kref);
+ get_device(clk->dev);
fp->private_data = clk;
}
out:
@@ -141,7 +139,7 @@ static int posix_clock_release(struct inode *inode, struct file *fp)
if (clk->ops.release)
err = clk->ops.release(clk);
- kref_put(&clk->kref, delete_clock);
+ put_device(clk->dev);
fp->private_data = NULL;
@@ -161,38 +159,35 @@ static const struct file_operations posix_clock_file_operations = {
#endif
};
-int posix_clock_register(struct posix_clock *clk, dev_t devid)
+int posix_clock_register(struct posix_clock *clk, struct device *dev)
{
int err;
- kref_init(&clk->kref);
init_rwsem(&clk->rwsem);
cdev_init(&clk->cdev, &posix_clock_file_operations);
+ err = cdev_device_add(&clk->cdev, dev);
+ if (err) {
+ pr_err("%s unable to add device %d:%d\n",
+ dev_name(dev), MAJOR(dev->devt), MINOR(dev->devt));
+ return err;
+ }
clk->cdev.owner = clk->ops.owner;
- err = cdev_add(&clk->cdev, devid, 1);
+ clk->dev = dev;
- return err;
+ return 0;
}
EXPORT_SYMBOL_GPL(posix_clock_register);
-static void delete_clock(struct kref *kref)
-{
- struct posix_clock *clk = container_of(kref, struct posix_clock, kref);
-
- if (clk->release)
- clk->release(clk);
-}
-
void posix_clock_unregister(struct posix_clock *clk)
{
- cdev_del(&clk->cdev);
+ cdev_device_del(&clk->cdev, clk->dev);
down_write(&clk->rwsem);
clk->zombie = true;
up_write(&clk->rwsem);
- kref_put(&clk->kref, delete_clock);
+ put_device(clk->dev);
}
EXPORT_SYMBOL_GPL(posix_clock_unregister);
diff --git a/kernel/time/sched_clock.c b/kernel/time/sched_clock.c
index 142b07619918..3f16750ec7a3 100644
--- a/kernel/time/sched_clock.c
+++ b/kernel/time/sched_clock.c
@@ -205,7 +205,8 @@ sched_clock_register(u64 (*read)(void), int bits, unsigned long rate)
if (sched_clock_timer.function != NULL) {
/* update timeout for clock wrap */
- hrtimer_start(&sched_clock_timer, cd.wrap_kt, HRTIMER_MODE_REL);
+ hrtimer_start(&sched_clock_timer, cd.wrap_kt,
+ HRTIMER_MODE_REL_HARD);
}
r = rate;
@@ -249,9 +250,9 @@ void __init generic_sched_clock_init(void)
* Start the timer to keep sched_clock() properly updated and
* sets the initial epoch.
*/
- hrtimer_init(&sched_clock_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ hrtimer_init(&sched_clock_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD);
sched_clock_timer.function = sched_clock_poll;
- hrtimer_start(&sched_clock_timer, cd.wrap_kt, HRTIMER_MODE_REL);
+ hrtimer_start(&sched_clock_timer, cd.wrap_kt, HRTIMER_MODE_REL_HARD);
}
/*
@@ -288,7 +289,7 @@ void sched_clock_resume(void)
struct clock_read_data *rd = &cd.read_data[0];
rd->epoch_cyc = cd.actual_read_sched_clock();
- hrtimer_start(&sched_clock_timer, cd.wrap_kt, HRTIMER_MODE_REL);
+ hrtimer_start(&sched_clock_timer, cd.wrap_kt, HRTIMER_MODE_REL_HARD);
rd->read_sched_clock = cd.actual_read_sched_clock;
}
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index f4ee1a3428ae..e59a34f23aa2 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -58,8 +58,9 @@ static void tick_do_update_jiffies64(ktime_t now)
/*
* Do a quick check without holding jiffies_lock:
+ * The READ_ONCE() pairs with two updates done later in this function.
*/
- delta = ktime_sub(now, last_jiffies_update);
+ delta = ktime_sub(now, READ_ONCE(last_jiffies_update));
if (delta < tick_period)
return;
@@ -70,8 +71,9 @@ static void tick_do_update_jiffies64(ktime_t now)
if (delta >= tick_period) {
delta = ktime_sub(delta, tick_period);
- last_jiffies_update = ktime_add(last_jiffies_update,
- tick_period);
+ /* Pairs with the lockless read in this function. */
+ WRITE_ONCE(last_jiffies_update,
+ ktime_add(last_jiffies_update, tick_period));
/* Slow path for long timeouts */
if (unlikely(delta >= tick_period)) {
@@ -79,8 +81,10 @@ static void tick_do_update_jiffies64(ktime_t now)
ticks = ktime_divns(delta, incr);
- last_jiffies_update = ktime_add_ns(last_jiffies_update,
- incr * ticks);
+ /* Pairs with the lockless read in this function. */
+ WRITE_ONCE(last_jiffies_update,
+ ktime_add_ns(last_jiffies_update,
+ incr * ticks));
}
do_timer(++ticks);
diff --git a/kernel/time/time.c b/kernel/time/time.c
index 7f7d6914ddd5..f5a6814c6743 100644
--- a/kernel/time/time.c
+++ b/kernel/time/time.c
@@ -877,7 +877,8 @@ int get_timespec64(struct timespec64 *ts,
ts->tv_sec = kts.tv_sec;
/* Zero out the padding for 32 bit systems or in compat mode */
- if (IS_ENABLED(CONFIG_64BIT_TIME) && in_compat_syscall())
+ if (IS_ENABLED(CONFIG_64BIT_TIME) && (!IS_ENABLED(CONFIG_64BIT) ||
+ in_compat_syscall()))
kts.tv_nsec &= 0xFFFFFFFFUL;
ts->tv_nsec = kts.tv_nsec;
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 44b726bab4bd..d911c8470149 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -819,7 +819,7 @@ ktime_t ktime_get_coarse_with_offset(enum tk_offsets offs)
} while (read_seqcount_retry(&tk_core.seq, seq));
- return base + nsecs;
+ return ktime_add_ns(base, nsecs);
}
EXPORT_SYMBOL_GPL(ktime_get_coarse_with_offset);
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 7d63b7347066..e70451eb2495 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -43,6 +43,7 @@
#include <linux/sched/debug.h>
#include <linux/slab.h>
#include <linux/compat.h>
+#include <linux/random.h>
#include <linux/uaccess.h>
#include <asm/unistd.h>
@@ -518,8 +519,8 @@ static int calc_wheel_index(unsigned long expires, unsigned long clk)
* Force expire obscene large timeouts to expire at the
* capacity limit of the wheel.
*/
- if (expires >= WHEEL_TIMEOUT_CUTOFF)
- expires = WHEEL_TIMEOUT_MAX;
+ if (delta >= WHEEL_TIMEOUT_CUTOFF)
+ expires = clk + WHEEL_TIMEOUT_MAX;
idx = calc_index(expires, LVL_DEPTH - 1);
}
@@ -581,7 +582,15 @@ trigger_dyntick_cpu(struct timer_base *base, struct timer_list *timer)
* Set the next expiry time and kick the CPU so it can reevaluate the
* wheel:
*/
- base->next_expiry = timer->expires;
+ if (time_before(timer->expires, base->clk)) {
+ /*
+ * Prevent from forward_timer_base() moving the base->clk
+ * backward
+ */
+ base->next_expiry = base->clk;
+ } else {
+ base->next_expiry = timer->expires;
+ }
wake_up_nohz_cpu(base->cpu);
}
@@ -893,10 +902,13 @@ static inline void forward_timer_base(struct timer_base *base)
* If the next expiry value is > jiffies, then we fast forward to
* jiffies otherwise we forward to the next expiry value.
*/
- if (time_after(base->next_expiry, jnow))
+ if (time_after(base->next_expiry, jnow)) {
base->clk = jnow;
- else
+ } else {
+ if (WARN_ON_ONCE(time_before(base->next_expiry, base->clk)))
+ return;
base->clk = base->next_expiry;
+ }
#endif
}
@@ -1646,6 +1658,13 @@ void update_process_times(int user_tick)
scheduler_tick();
if (IS_ENABLED(CONFIG_POSIX_TIMERS))
run_posix_cpu_timers(p);
+
+ /* The current CPU might make use of net randoms without receiving IRQs
+ * to renew them often enough. Let's update the net_rand_state from a
+ * non-constant value that's not affine to the number of calls to make
+ * sure it's updated when there's some activity (we don't care in idle).
+ */
+ this_cpu_add(net_rand_state.s1, rol32(jiffies, 24) + user_tick);
}
/**
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-05-06 19:40:37 +0000