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-rw-r--r--kernel/time/clockevents.c9
-rw-r--r--kernel/time/clocksource.c2
-rw-r--r--kernel/time/posix-cpu-timers.c6
-rw-r--r--kernel/time/sched_clock.c13
-rw-r--r--kernel/time/tick-sched.c12
-rw-r--r--kernel/time/timekeeping.c54
-rw-r--r--kernel/time/timer.c90
7 files changed, 139 insertions, 47 deletions
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index 003ccf338d20..5d85014d59b5 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -690,7 +690,7 @@ static ssize_t unbind_device_store(struct device *dev,
{
char name[CS_NAME_LEN];
ssize_t ret = sysfs_get_uname(buf, name, count);
- struct clock_event_device *ce;
+ struct clock_event_device *ce = NULL, *iter;
if (ret < 0)
return ret;
@@ -698,9 +698,10 @@ static ssize_t unbind_device_store(struct device *dev,
ret = -ENODEV;
mutex_lock(&clockevents_mutex);
raw_spin_lock_irq(&clockevents_lock);
- list_for_each_entry(ce, &clockevent_devices, list) {
- if (!strcmp(ce->name, name)) {
- ret = __clockevents_try_unbind(ce, dev->id);
+ list_for_each_entry(iter, &clockevent_devices, list) {
+ if (!strcmp(iter->name, name)) {
+ ret = __clockevents_try_unbind(iter, dev->id);
+ ce = iter;
break;
}
}
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 95d7ca35bdf2..cee5da1e54c4 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -343,7 +343,7 @@ void clocksource_verify_percpu(struct clocksource *cs)
cpus_read_lock();
preempt_disable();
clocksource_verify_choose_cpus();
- if (cpumask_weight(&cpus_chosen) == 0) {
+ if (cpumask_empty(&cpus_chosen)) {
preempt_enable();
cpus_read_unlock();
pr_warn("Not enough CPUs to check clocksource '%s'.\n", cs->name);
diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 0a97193984db..cb925e8ef9a8 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -870,7 +870,7 @@ static inline void check_dl_overrun(struct task_struct *tsk)
{
if (tsk->dl.dl_overrun) {
tsk->dl.dl_overrun = 0;
- __group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk);
+ send_signal_locked(SIGXCPU, SEND_SIG_PRIV, tsk, PIDTYPE_TGID);
}
}
@@ -884,7 +884,7 @@ static bool check_rlimit(u64 time, u64 limit, int signo, bool rt, bool hard)
rt ? "RT" : "CPU", hard ? "hard" : "soft",
current->comm, task_pid_nr(current));
}
- __group_send_sig_info(signo, SEND_SIG_PRIV, current);
+ send_signal_locked(signo, SEND_SIG_PRIV, current, PIDTYPE_TGID);
return true;
}
@@ -958,7 +958,7 @@ static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it,
trace_itimer_expire(signo == SIGPROF ?
ITIMER_PROF : ITIMER_VIRTUAL,
task_tgid(tsk), cur_time);
- __group_send_sig_info(signo, SEND_SIG_PRIV, tsk);
+ send_signal_locked(signo, SEND_SIG_PRIV, tsk, PIDTYPE_TGID);
}
if (it->expires && it->expires < *expires)
diff --git a/kernel/time/sched_clock.c b/kernel/time/sched_clock.c
index b1b9b12899f5..8464c5acc913 100644
--- a/kernel/time/sched_clock.c
+++ b/kernel/time/sched_clock.c
@@ -8,6 +8,7 @@
#include <linux/jiffies.h>
#include <linux/ktime.h>
#include <linux/kernel.h>
+#include <linux/math.h>
#include <linux/moduleparam.h>
#include <linux/sched.h>
#include <linux/sched/clock.h>
@@ -199,15 +200,13 @@ sched_clock_register(u64 (*read)(void), int bits, unsigned long rate)
r = rate;
if (r >= 4000000) {
- r /= 1000000;
+ r = DIV_ROUND_CLOSEST(r, 1000000);
r_unit = 'M';
+ } else if (r >= 4000) {
+ r = DIV_ROUND_CLOSEST(r, 1000);
+ r_unit = 'k';
} else {
- if (r >= 1000) {
- r /= 1000;
- r_unit = 'k';
- } else {
- r_unit = ' ';
- }
+ r_unit = ' ';
}
/* Calculate the ns resolution of this counter */
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index d257721c68b8..58a11f859ac7 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -928,6 +928,8 @@ static void tick_nohz_stop_tick(struct tick_sched *ts, int cpu)
if (unlikely(expires == KTIME_MAX)) {
if (ts->nohz_mode == NOHZ_MODE_HIGHRES)
hrtimer_cancel(&ts->sched_timer);
+ else
+ tick_program_event(KTIME_MAX, 1);
return;
}
@@ -1364,9 +1366,15 @@ static void tick_nohz_handler(struct clock_event_device *dev)
tick_sched_do_timer(ts, now);
tick_sched_handle(ts, regs);
- /* No need to reprogram if we are running tickless */
- if (unlikely(ts->tick_stopped))
+ if (unlikely(ts->tick_stopped)) {
+ /*
+ * The clockevent device is not reprogrammed, so change the
+ * clock event device to ONESHOT_STOPPED to avoid spurious
+ * interrupts on devices which might not be truly one shot.
+ */
+ tick_program_event(KTIME_MAX, 1);
return;
+ }
hrtimer_forward(&ts->sched_timer, now, TICK_NSEC);
tick_program_event(hrtimer_get_expires(&ts->sched_timer), 1);
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 3b1398fbddaf..8e4b3c32fcf9 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -17,6 +17,7 @@
#include <linux/clocksource.h>
#include <linux/jiffies.h>
#include <linux/time.h>
+#include <linux/timex.h>
#include <linux/tick.h>
#include <linux/stop_machine.h>
#include <linux/pvclock_gtod.h>
@@ -429,6 +430,14 @@ static void update_fast_timekeeper(const struct tk_read_base *tkr,
memcpy(base + 1, base, sizeof(*base));
}
+static __always_inline u64 fast_tk_get_delta_ns(struct tk_read_base *tkr)
+{
+ u64 delta, cycles = tk_clock_read(tkr);
+
+ delta = clocksource_delta(cycles, tkr->cycle_last, tkr->mask);
+ return timekeeping_delta_to_ns(tkr, delta);
+}
+
static __always_inline u64 __ktime_get_fast_ns(struct tk_fast *tkf)
{
struct tk_read_base *tkr;
@@ -439,12 +448,7 @@ static __always_inline u64 __ktime_get_fast_ns(struct tk_fast *tkf)
seq = raw_read_seqcount_latch(&tkf->seq);
tkr = tkf->base + (seq & 0x01);
now = ktime_to_ns(tkr->base);
-
- now += timekeeping_delta_to_ns(tkr,
- clocksource_delta(
- tk_clock_read(tkr),
- tkr->cycle_last,
- tkr->mask));
+ now += fast_tk_get_delta_ns(tkr);
} while (read_seqcount_latch_retry(&tkf->seq, seq));
return now;
@@ -528,10 +532,27 @@ u64 notrace ktime_get_boot_fast_ns(void)
{
struct timekeeper *tk = &tk_core.timekeeper;
- return (ktime_get_mono_fast_ns() + ktime_to_ns(tk->offs_boot));
+ return (ktime_get_mono_fast_ns() + ktime_to_ns(data_race(tk->offs_boot)));
}
EXPORT_SYMBOL_GPL(ktime_get_boot_fast_ns);
+/**
+ * ktime_get_tai_fast_ns - NMI safe and fast access to tai clock.
+ *
+ * The same limitations as described for ktime_get_boot_fast_ns() apply. The
+ * mono time and the TAI offset are not read atomically which may yield wrong
+ * readouts. However, an update of the TAI offset is an rare event e.g., caused
+ * by settime or adjtimex with an offset. The user of this function has to deal
+ * with the possibility of wrong timestamps in post processing.
+ */
+u64 notrace ktime_get_tai_fast_ns(void)
+{
+ struct timekeeper *tk = &tk_core.timekeeper;
+
+ return (ktime_get_mono_fast_ns() + ktime_to_ns(data_race(tk->offs_tai)));
+}
+EXPORT_SYMBOL_GPL(ktime_get_tai_fast_ns);
+
static __always_inline u64 __ktime_get_real_fast(struct tk_fast *tkf, u64 *mono)
{
struct tk_read_base *tkr;
@@ -543,10 +564,7 @@ static __always_inline u64 __ktime_get_real_fast(struct tk_fast *tkf, u64 *mono)
tkr = tkf->base + (seq & 0x01);
basem = ktime_to_ns(tkr->base);
baser = ktime_to_ns(tkr->base_real);
-
- delta = timekeeping_delta_to_ns(tkr,
- clocksource_delta(tk_clock_read(tkr),
- tkr->cycle_last, tkr->mask));
+ delta = fast_tk_get_delta_ns(tkr);
} while (read_seqcount_latch_retry(&tkf->seq, seq));
if (mono)
@@ -2380,6 +2398,20 @@ static int timekeeping_validate_timex(const struct __kernel_timex *txc)
return 0;
}
+/**
+ * random_get_entropy_fallback - Returns the raw clock source value,
+ * used by random.c for platforms with no valid random_get_entropy().
+ */
+unsigned long random_get_entropy_fallback(void)
+{
+ struct tk_read_base *tkr = &tk_core.timekeeper.tkr_mono;
+ struct clocksource *clock = READ_ONCE(tkr->clock);
+
+ if (unlikely(timekeeping_suspended || !clock))
+ return 0;
+ return clock->read(clock);
+}
+EXPORT_SYMBOL_GPL(random_get_entropy_fallback);
/**
* do_adjtimex() - Accessor function to NTP __do_adjtimex function
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 9dd2a39cb3b0..717fcb9fb14a 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -44,6 +44,7 @@
#include <linux/slab.h>
#include <linux/compat.h>
#include <linux/random.h>
+#include <linux/sysctl.h>
#include <linux/uaccess.h>
#include <asm/unistd.h>
@@ -223,7 +224,7 @@ static void timer_update_keys(struct work_struct *work);
static DECLARE_WORK(timer_update_work, timer_update_keys);
#ifdef CONFIG_SMP
-unsigned int sysctl_timer_migration = 1;
+static unsigned int sysctl_timer_migration = 1;
DEFINE_STATIC_KEY_FALSE(timers_migration_enabled);
@@ -234,7 +235,42 @@ static void timers_update_migration(void)
else
static_branch_disable(&timers_migration_enabled);
}
-#else
+
+#ifdef CONFIG_SYSCTL
+static int timer_migration_handler(struct ctl_table *table, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+{
+ int ret;
+
+ mutex_lock(&timer_keys_mutex);
+ ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
+ if (!ret && write)
+ timers_update_migration();
+ mutex_unlock(&timer_keys_mutex);
+ return ret;
+}
+
+static struct ctl_table timer_sysctl[] = {
+ {
+ .procname = "timer_migration",
+ .data = &sysctl_timer_migration,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = timer_migration_handler,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_ONE,
+ },
+ {}
+};
+
+static int __init timer_sysctl_init(void)
+{
+ register_sysctl("kernel", timer_sysctl);
+ return 0;
+}
+device_initcall(timer_sysctl_init);
+#endif /* CONFIG_SYSCTL */
+#else /* CONFIG_SMP */
static inline void timers_update_migration(void) { }
#endif /* !CONFIG_SMP */
@@ -251,19 +287,6 @@ void timers_update_nohz(void)
schedule_work(&timer_update_work);
}
-int timer_migration_handler(struct ctl_table *table, int write,
- void *buffer, size_t *lenp, loff_t *ppos)
-{
- int ret;
-
- mutex_lock(&timer_keys_mutex);
- ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
- if (!ret && write)
- timers_update_migration();
- mutex_unlock(&timer_keys_mutex);
- return ret;
-}
-
static inline bool is_timers_nohz_active(void)
{
return static_branch_unlikely(&timers_nohz_active);
@@ -502,7 +525,7 @@ static inline unsigned calc_index(unsigned long expires, unsigned lvl,
*
* Round up with level granularity to prevent this.
*/
- expires = (expires + LVL_GRAN(lvl)) >> LVL_SHIFT(lvl);
+ expires = (expires >> LVL_SHIFT(lvl)) + 1;
*bucket_expiry = expires << LVL_SHIFT(lvl);
return LVL_OFFS(lvl) + (expires & LVL_MASK);
}
@@ -615,9 +638,39 @@ static void internal_add_timer(struct timer_base *base, struct timer_list *timer
static const struct debug_obj_descr timer_debug_descr;
+struct timer_hint {
+ void (*function)(struct timer_list *t);
+ long offset;
+};
+
+#define TIMER_HINT(fn, container, timr, hintfn) \
+ { \
+ .function = fn, \
+ .offset = offsetof(container, hintfn) - \
+ offsetof(container, timr) \
+ }
+
+static const struct timer_hint timer_hints[] = {
+ TIMER_HINT(delayed_work_timer_fn,
+ struct delayed_work, timer, work.func),
+ TIMER_HINT(kthread_delayed_work_timer_fn,
+ struct kthread_delayed_work, timer, work.func),
+};
+
static void *timer_debug_hint(void *addr)
{
- return ((struct timer_list *) addr)->function;
+ struct timer_list *timer = addr;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(timer_hints); i++) {
+ if (timer_hints[i].function == timer->function) {
+ void (**fn)(void) = addr + timer_hints[i].offset;
+
+ return *fn;
+ }
+ }
+
+ return timer->function;
}
static bool timer_is_static_object(void *addr)
@@ -1780,8 +1833,6 @@ void update_process_times(int user_tick)
{
struct task_struct *p = current;
- PRANDOM_ADD_NOISE(jiffies, user_tick, p, 0);
-
/* Note: this timer irq context must be accounted for as well. */
account_process_tick(p, user_tick);
run_local_timers();
@@ -1953,6 +2004,7 @@ int timers_prepare_cpu(unsigned int cpu)
base = per_cpu_ptr(&timer_bases[b], cpu);
base->clk = jiffies;
base->next_expiry = base->clk + NEXT_TIMER_MAX_DELTA;
+ base->next_expiry_recalc = false;
base->timers_pending = false;
base->is_idle = false;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-10-30 14:04:20 +0000