![Andrew Morton](/assets/img/avatar_default.png)
Switch everything to the new and more capable implementation of abs(). Mainly to give the new abs() a bit of a workout. Cc: Michal Nazarewicz <mina86@mina86.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2056 lines
55 KiB
C
2056 lines
55 KiB
C
/*
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* linux/kernel/time/timekeeping.c
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*
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* Kernel timekeeping code and accessor functions
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*
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* This code was moved from linux/kernel/timer.c.
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* Please see that file for copyright and history logs.
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*
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*/
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#include <linux/timekeeper_internal.h>
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#include <linux/module.h>
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#include <linux/interrupt.h>
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#include <linux/percpu.h>
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#include <linux/init.h>
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#include <linux/mm.h>
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#include <linux/sched.h>
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#include <linux/syscore_ops.h>
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#include <linux/clocksource.h>
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#include <linux/jiffies.h>
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#include <linux/time.h>
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#include <linux/tick.h>
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#include <linux/stop_machine.h>
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#include <linux/pvclock_gtod.h>
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#include <linux/compiler.h>
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#include "tick-internal.h"
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#include "ntp_internal.h"
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#include "timekeeping_internal.h"
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#define TK_CLEAR_NTP (1 << 0)
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#define TK_MIRROR (1 << 1)
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#define TK_CLOCK_WAS_SET (1 << 2)
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/*
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* The most important data for readout fits into a single 64 byte
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* cache line.
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*/
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static struct {
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seqcount_t seq;
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struct timekeeper timekeeper;
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} tk_core ____cacheline_aligned;
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static DEFINE_RAW_SPINLOCK(timekeeper_lock);
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static struct timekeeper shadow_timekeeper;
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/**
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* struct tk_fast - NMI safe timekeeper
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* @seq: Sequence counter for protecting updates. The lowest bit
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* is the index for the tk_read_base array
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* @base: tk_read_base array. Access is indexed by the lowest bit of
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* @seq.
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*
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* See @update_fast_timekeeper() below.
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*/
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struct tk_fast {
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seqcount_t seq;
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struct tk_read_base base[2];
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};
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static struct tk_fast tk_fast_mono ____cacheline_aligned;
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static struct tk_fast tk_fast_raw ____cacheline_aligned;
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/* flag for if timekeeping is suspended */
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int __read_mostly timekeeping_suspended;
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static inline void tk_normalize_xtime(struct timekeeper *tk)
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{
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while (tk->tkr_mono.xtime_nsec >= ((u64)NSEC_PER_SEC << tk->tkr_mono.shift)) {
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tk->tkr_mono.xtime_nsec -= (u64)NSEC_PER_SEC << tk->tkr_mono.shift;
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tk->xtime_sec++;
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}
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}
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static inline struct timespec64 tk_xtime(struct timekeeper *tk)
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{
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struct timespec64 ts;
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ts.tv_sec = tk->xtime_sec;
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ts.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift);
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return ts;
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}
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static void tk_set_xtime(struct timekeeper *tk, const struct timespec64 *ts)
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{
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tk->xtime_sec = ts->tv_sec;
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tk->tkr_mono.xtime_nsec = (u64)ts->tv_nsec << tk->tkr_mono.shift;
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}
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static void tk_xtime_add(struct timekeeper *tk, const struct timespec64 *ts)
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{
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tk->xtime_sec += ts->tv_sec;
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tk->tkr_mono.xtime_nsec += (u64)ts->tv_nsec << tk->tkr_mono.shift;
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tk_normalize_xtime(tk);
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}
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static void tk_set_wall_to_mono(struct timekeeper *tk, struct timespec64 wtm)
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{
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struct timespec64 tmp;
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/*
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* Verify consistency of: offset_real = -wall_to_monotonic
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* before modifying anything
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*/
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set_normalized_timespec64(&tmp, -tk->wall_to_monotonic.tv_sec,
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-tk->wall_to_monotonic.tv_nsec);
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WARN_ON_ONCE(tk->offs_real.tv64 != timespec64_to_ktime(tmp).tv64);
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tk->wall_to_monotonic = wtm;
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set_normalized_timespec64(&tmp, -wtm.tv_sec, -wtm.tv_nsec);
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tk->offs_real = timespec64_to_ktime(tmp);
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tk->offs_tai = ktime_add(tk->offs_real, ktime_set(tk->tai_offset, 0));
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}
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static inline void tk_update_sleep_time(struct timekeeper *tk, ktime_t delta)
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{
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tk->offs_boot = ktime_add(tk->offs_boot, delta);
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}
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#ifdef CONFIG_DEBUG_TIMEKEEPING
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#define WARNING_FREQ (HZ*300) /* 5 minute rate-limiting */
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static void timekeeping_check_update(struct timekeeper *tk, cycle_t offset)
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{
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cycle_t max_cycles = tk->tkr_mono.clock->max_cycles;
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const char *name = tk->tkr_mono.clock->name;
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if (offset > max_cycles) {
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printk_deferred("WARNING: timekeeping: Cycle offset (%lld) is larger than allowed by the '%s' clock's max_cycles value (%lld): time overflow danger\n",
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offset, name, max_cycles);
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printk_deferred(" timekeeping: Your kernel is sick, but tries to cope by capping time updates\n");
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} else {
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if (offset > (max_cycles >> 1)) {
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printk_deferred("INFO: timekeeping: Cycle offset (%lld) is larger than the the '%s' clock's 50%% safety margin (%lld)\n",
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offset, name, max_cycles >> 1);
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printk_deferred(" timekeeping: Your kernel is still fine, but is feeling a bit nervous\n");
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}
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}
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if (tk->underflow_seen) {
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if (jiffies - tk->last_warning > WARNING_FREQ) {
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printk_deferred("WARNING: Underflow in clocksource '%s' observed, time update ignored.\n", name);
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printk_deferred(" Please report this, consider using a different clocksource, if possible.\n");
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printk_deferred(" Your kernel is probably still fine.\n");
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tk->last_warning = jiffies;
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}
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tk->underflow_seen = 0;
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}
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if (tk->overflow_seen) {
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if (jiffies - tk->last_warning > WARNING_FREQ) {
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printk_deferred("WARNING: Overflow in clocksource '%s' observed, time update capped.\n", name);
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printk_deferred(" Please report this, consider using a different clocksource, if possible.\n");
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printk_deferred(" Your kernel is probably still fine.\n");
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tk->last_warning = jiffies;
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}
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tk->overflow_seen = 0;
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}
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}
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static inline cycle_t timekeeping_get_delta(struct tk_read_base *tkr)
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{
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struct timekeeper *tk = &tk_core.timekeeper;
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cycle_t now, last, mask, max, delta;
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unsigned int seq;
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/*
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* Since we're called holding a seqlock, the data may shift
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* under us while we're doing the calculation. This can cause
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* false positives, since we'd note a problem but throw the
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* results away. So nest another seqlock here to atomically
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* grab the points we are checking with.
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*/
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do {
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seq = read_seqcount_begin(&tk_core.seq);
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now = tkr->read(tkr->clock);
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last = tkr->cycle_last;
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mask = tkr->mask;
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max = tkr->clock->max_cycles;
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} while (read_seqcount_retry(&tk_core.seq, seq));
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delta = clocksource_delta(now, last, mask);
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/*
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* Try to catch underflows by checking if we are seeing small
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* mask-relative negative values.
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*/
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if (unlikely((~delta & mask) < (mask >> 3))) {
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tk->underflow_seen = 1;
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delta = 0;
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}
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/* Cap delta value to the max_cycles values to avoid mult overflows */
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if (unlikely(delta > max)) {
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tk->overflow_seen = 1;
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delta = tkr->clock->max_cycles;
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}
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return delta;
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}
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#else
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static inline void timekeeping_check_update(struct timekeeper *tk, cycle_t offset)
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{
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}
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static inline cycle_t timekeeping_get_delta(struct tk_read_base *tkr)
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{
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cycle_t cycle_now, delta;
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/* read clocksource */
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cycle_now = tkr->read(tkr->clock);
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/* calculate the delta since the last update_wall_time */
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delta = clocksource_delta(cycle_now, tkr->cycle_last, tkr->mask);
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return delta;
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}
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#endif
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/**
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* tk_setup_internals - Set up internals to use clocksource clock.
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*
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* @tk: The target timekeeper to setup.
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* @clock: Pointer to clocksource.
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*
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* Calculates a fixed cycle/nsec interval for a given clocksource/adjustment
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* pair and interval request.
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*
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* Unless you're the timekeeping code, you should not be using this!
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*/
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static void tk_setup_internals(struct timekeeper *tk, struct clocksource *clock)
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{
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cycle_t interval;
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u64 tmp, ntpinterval;
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struct clocksource *old_clock;
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old_clock = tk->tkr_mono.clock;
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tk->tkr_mono.clock = clock;
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tk->tkr_mono.read = clock->read;
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tk->tkr_mono.mask = clock->mask;
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tk->tkr_mono.cycle_last = tk->tkr_mono.read(clock);
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tk->tkr_raw.clock = clock;
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tk->tkr_raw.read = clock->read;
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tk->tkr_raw.mask = clock->mask;
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tk->tkr_raw.cycle_last = tk->tkr_mono.cycle_last;
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/* Do the ns -> cycle conversion first, using original mult */
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tmp = NTP_INTERVAL_LENGTH;
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tmp <<= clock->shift;
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ntpinterval = tmp;
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tmp += clock->mult/2;
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do_div(tmp, clock->mult);
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if (tmp == 0)
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tmp = 1;
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interval = (cycle_t) tmp;
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tk->cycle_interval = interval;
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/* Go back from cycles -> shifted ns */
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tk->xtime_interval = (u64) interval * clock->mult;
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tk->xtime_remainder = ntpinterval - tk->xtime_interval;
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tk->raw_interval =
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((u64) interval * clock->mult) >> clock->shift;
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/* if changing clocks, convert xtime_nsec shift units */
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if (old_clock) {
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int shift_change = clock->shift - old_clock->shift;
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if (shift_change < 0)
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tk->tkr_mono.xtime_nsec >>= -shift_change;
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else
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tk->tkr_mono.xtime_nsec <<= shift_change;
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}
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tk->tkr_raw.xtime_nsec = 0;
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tk->tkr_mono.shift = clock->shift;
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tk->tkr_raw.shift = clock->shift;
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tk->ntp_error = 0;
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tk->ntp_error_shift = NTP_SCALE_SHIFT - clock->shift;
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tk->ntp_tick = ntpinterval << tk->ntp_error_shift;
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/*
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* The timekeeper keeps its own mult values for the currently
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* active clocksource. These value will be adjusted via NTP
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* to counteract clock drifting.
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*/
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tk->tkr_mono.mult = clock->mult;
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tk->tkr_raw.mult = clock->mult;
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tk->ntp_err_mult = 0;
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}
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/* Timekeeper helper functions. */
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#ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
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static u32 default_arch_gettimeoffset(void) { return 0; }
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u32 (*arch_gettimeoffset)(void) = default_arch_gettimeoffset;
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#else
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static inline u32 arch_gettimeoffset(void) { return 0; }
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#endif
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static inline s64 timekeeping_get_ns(struct tk_read_base *tkr)
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{
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cycle_t delta;
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s64 nsec;
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delta = timekeeping_get_delta(tkr);
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nsec = delta * tkr->mult + tkr->xtime_nsec;
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nsec >>= tkr->shift;
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/* If arch requires, add in get_arch_timeoffset() */
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return nsec + arch_gettimeoffset();
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}
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/**
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* update_fast_timekeeper - Update the fast and NMI safe monotonic timekeeper.
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* @tkr: Timekeeping readout base from which we take the update
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*
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* We want to use this from any context including NMI and tracing /
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* instrumenting the timekeeping code itself.
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*
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* Employ the latch technique; see @raw_write_seqcount_latch.
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*
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* So if a NMI hits the update of base[0] then it will use base[1]
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* which is still consistent. In the worst case this can result is a
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* slightly wrong timestamp (a few nanoseconds). See
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* @ktime_get_mono_fast_ns.
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*/
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static void update_fast_timekeeper(struct tk_read_base *tkr, struct tk_fast *tkf)
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{
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struct tk_read_base *base = tkf->base;
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/* Force readers off to base[1] */
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raw_write_seqcount_latch(&tkf->seq);
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/* Update base[0] */
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memcpy(base, tkr, sizeof(*base));
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/* Force readers back to base[0] */
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raw_write_seqcount_latch(&tkf->seq);
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/* Update base[1] */
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memcpy(base + 1, base, sizeof(*base));
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}
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/**
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* ktime_get_mono_fast_ns - Fast NMI safe access to clock monotonic
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*
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* This timestamp is not guaranteed to be monotonic across an update.
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* The timestamp is calculated by:
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*
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* now = base_mono + clock_delta * slope
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*
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* So if the update lowers the slope, readers who are forced to the
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* not yet updated second array are still using the old steeper slope.
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*
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* tmono
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* ^
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* | o n
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* | o n
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* | u
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* | o
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* |o
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* |12345678---> reader order
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*
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* o = old slope
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* u = update
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* n = new slope
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*
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* So reader 6 will observe time going backwards versus reader 5.
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*
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* While other CPUs are likely to be able observe that, the only way
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* for a CPU local observation is when an NMI hits in the middle of
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* the update. Timestamps taken from that NMI context might be ahead
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* of the following timestamps. Callers need to be aware of that and
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* deal with it.
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*/
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static __always_inline u64 __ktime_get_fast_ns(struct tk_fast *tkf)
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{
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struct tk_read_base *tkr;
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unsigned int seq;
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u64 now;
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do {
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seq = raw_read_seqcount_latch(&tkf->seq);
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tkr = tkf->base + (seq & 0x01);
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now = ktime_to_ns(tkr->base) + timekeeping_get_ns(tkr);
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} while (read_seqcount_retry(&tkf->seq, seq));
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return now;
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}
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u64 ktime_get_mono_fast_ns(void)
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{
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return __ktime_get_fast_ns(&tk_fast_mono);
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}
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EXPORT_SYMBOL_GPL(ktime_get_mono_fast_ns);
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u64 ktime_get_raw_fast_ns(void)
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{
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return __ktime_get_fast_ns(&tk_fast_raw);
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}
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EXPORT_SYMBOL_GPL(ktime_get_raw_fast_ns);
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/* Suspend-time cycles value for halted fast timekeeper. */
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static cycle_t cycles_at_suspend;
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static cycle_t dummy_clock_read(struct clocksource *cs)
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{
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return cycles_at_suspend;
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}
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/**
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* halt_fast_timekeeper - Prevent fast timekeeper from accessing clocksource.
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* @tk: Timekeeper to snapshot.
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*
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* It generally is unsafe to access the clocksource after timekeeping has been
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* suspended, so take a snapshot of the readout base of @tk and use it as the
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* fast timekeeper's readout base while suspended. It will return the same
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* number of cycles every time until timekeeping is resumed at which time the
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* proper readout base for the fast timekeeper will be restored automatically.
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*/
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static void halt_fast_timekeeper(struct timekeeper *tk)
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{
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static struct tk_read_base tkr_dummy;
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struct tk_read_base *tkr = &tk->tkr_mono;
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memcpy(&tkr_dummy, tkr, sizeof(tkr_dummy));
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cycles_at_suspend = tkr->read(tkr->clock);
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tkr_dummy.read = dummy_clock_read;
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update_fast_timekeeper(&tkr_dummy, &tk_fast_mono);
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tkr = &tk->tkr_raw;
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memcpy(&tkr_dummy, tkr, sizeof(tkr_dummy));
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tkr_dummy.read = dummy_clock_read;
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update_fast_timekeeper(&tkr_dummy, &tk_fast_raw);
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}
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#ifdef CONFIG_GENERIC_TIME_VSYSCALL_OLD
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static inline void update_vsyscall(struct timekeeper *tk)
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{
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struct timespec xt, wm;
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xt = timespec64_to_timespec(tk_xtime(tk));
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wm = timespec64_to_timespec(tk->wall_to_monotonic);
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update_vsyscall_old(&xt, &wm, tk->tkr_mono.clock, tk->tkr_mono.mult,
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tk->tkr_mono.cycle_last);
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}
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static inline void old_vsyscall_fixup(struct timekeeper *tk)
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{
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s64 remainder;
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/*
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* Store only full nanoseconds into xtime_nsec after rounding
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* it up and add the remainder to the error difference.
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* XXX - This is necessary to avoid small 1ns inconsistnecies caused
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* by truncating the remainder in vsyscalls. However, it causes
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* additional work to be done in timekeeping_adjust(). Once
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* the vsyscall implementations are converted to use xtime_nsec
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* (shifted nanoseconds), and CONFIG_GENERIC_TIME_VSYSCALL_OLD
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* users are removed, this can be killed.
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*/
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remainder = tk->tkr_mono.xtime_nsec & ((1ULL << tk->tkr_mono.shift) - 1);
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tk->tkr_mono.xtime_nsec -= remainder;
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tk->tkr_mono.xtime_nsec += 1ULL << tk->tkr_mono.shift;
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tk->ntp_error += remainder << tk->ntp_error_shift;
|
|
tk->ntp_error -= (1ULL << tk->tkr_mono.shift) << tk->ntp_error_shift;
|
|
}
|
|
#else
|
|
#define old_vsyscall_fixup(tk)
|
|
#endif
|
|
|
|
static RAW_NOTIFIER_HEAD(pvclock_gtod_chain);
|
|
|
|
static void update_pvclock_gtod(struct timekeeper *tk, bool was_set)
|
|
{
|
|
raw_notifier_call_chain(&pvclock_gtod_chain, was_set, tk);
|
|
}
|
|
|
|
/**
|
|
* pvclock_gtod_register_notifier - register a pvclock timedata update listener
|
|
*/
|
|
int pvclock_gtod_register_notifier(struct notifier_block *nb)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned long flags;
|
|
int ret;
|
|
|
|
raw_spin_lock_irqsave(&timekeeper_lock, flags);
|
|
ret = raw_notifier_chain_register(&pvclock_gtod_chain, nb);
|
|
update_pvclock_gtod(tk, true);
|
|
raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(pvclock_gtod_register_notifier);
|
|
|
|
/**
|
|
* pvclock_gtod_unregister_notifier - unregister a pvclock
|
|
* timedata update listener
|
|
*/
|
|
int pvclock_gtod_unregister_notifier(struct notifier_block *nb)
|
|
{
|
|
unsigned long flags;
|
|
int ret;
|
|
|
|
raw_spin_lock_irqsave(&timekeeper_lock, flags);
|
|
ret = raw_notifier_chain_unregister(&pvclock_gtod_chain, nb);
|
|
raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(pvclock_gtod_unregister_notifier);
|
|
|
|
/*
|
|
* tk_update_leap_state - helper to update the next_leap_ktime
|
|
*/
|
|
static inline void tk_update_leap_state(struct timekeeper *tk)
|
|
{
|
|
tk->next_leap_ktime = ntp_get_next_leap();
|
|
if (tk->next_leap_ktime.tv64 != KTIME_MAX)
|
|
/* Convert to monotonic time */
|
|
tk->next_leap_ktime = ktime_sub(tk->next_leap_ktime, tk->offs_real);
|
|
}
|
|
|
|
/*
|
|
* Update the ktime_t based scalar nsec members of the timekeeper
|
|
*/
|
|
static inline void tk_update_ktime_data(struct timekeeper *tk)
|
|
{
|
|
u64 seconds;
|
|
u32 nsec;
|
|
|
|
/*
|
|
* The xtime based monotonic readout is:
|
|
* nsec = (xtime_sec + wtm_sec) * 1e9 + wtm_nsec + now();
|
|
* The ktime based monotonic readout is:
|
|
* nsec = base_mono + now();
|
|
* ==> base_mono = (xtime_sec + wtm_sec) * 1e9 + wtm_nsec
|
|
*/
|
|
seconds = (u64)(tk->xtime_sec + tk->wall_to_monotonic.tv_sec);
|
|
nsec = (u32) tk->wall_to_monotonic.tv_nsec;
|
|
tk->tkr_mono.base = ns_to_ktime(seconds * NSEC_PER_SEC + nsec);
|
|
|
|
/* Update the monotonic raw base */
|
|
tk->tkr_raw.base = timespec64_to_ktime(tk->raw_time);
|
|
|
|
/*
|
|
* The sum of the nanoseconds portions of xtime and
|
|
* wall_to_monotonic can be greater/equal one second. Take
|
|
* this into account before updating tk->ktime_sec.
|
|
*/
|
|
nsec += (u32)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift);
|
|
if (nsec >= NSEC_PER_SEC)
|
|
seconds++;
|
|
tk->ktime_sec = seconds;
|
|
}
|
|
|
|
/* must hold timekeeper_lock */
|
|
static void timekeeping_update(struct timekeeper *tk, unsigned int action)
|
|
{
|
|
if (action & TK_CLEAR_NTP) {
|
|
tk->ntp_error = 0;
|
|
ntp_clear();
|
|
}
|
|
|
|
tk_update_leap_state(tk);
|
|
tk_update_ktime_data(tk);
|
|
|
|
update_vsyscall(tk);
|
|
update_pvclock_gtod(tk, action & TK_CLOCK_WAS_SET);
|
|
|
|
update_fast_timekeeper(&tk->tkr_mono, &tk_fast_mono);
|
|
update_fast_timekeeper(&tk->tkr_raw, &tk_fast_raw);
|
|
|
|
if (action & TK_CLOCK_WAS_SET)
|
|
tk->clock_was_set_seq++;
|
|
/*
|
|
* The mirroring of the data to the shadow-timekeeper needs
|
|
* to happen last here to ensure we don't over-write the
|
|
* timekeeper structure on the next update with stale data
|
|
*/
|
|
if (action & TK_MIRROR)
|
|
memcpy(&shadow_timekeeper, &tk_core.timekeeper,
|
|
sizeof(tk_core.timekeeper));
|
|
}
|
|
|
|
/**
|
|
* timekeeping_forward_now - update clock to the current time
|
|
*
|
|
* Forward the current clock to update its state since the last call to
|
|
* update_wall_time(). This is useful before significant clock changes,
|
|
* as it avoids having to deal with this time offset explicitly.
|
|
*/
|
|
static void timekeeping_forward_now(struct timekeeper *tk)
|
|
{
|
|
struct clocksource *clock = tk->tkr_mono.clock;
|
|
cycle_t cycle_now, delta;
|
|
s64 nsec;
|
|
|
|
cycle_now = tk->tkr_mono.read(clock);
|
|
delta = clocksource_delta(cycle_now, tk->tkr_mono.cycle_last, tk->tkr_mono.mask);
|
|
tk->tkr_mono.cycle_last = cycle_now;
|
|
tk->tkr_raw.cycle_last = cycle_now;
|
|
|
|
tk->tkr_mono.xtime_nsec += delta * tk->tkr_mono.mult;
|
|
|
|
/* If arch requires, add in get_arch_timeoffset() */
|
|
tk->tkr_mono.xtime_nsec += (u64)arch_gettimeoffset() << tk->tkr_mono.shift;
|
|
|
|
tk_normalize_xtime(tk);
|
|
|
|
nsec = clocksource_cyc2ns(delta, tk->tkr_raw.mult, tk->tkr_raw.shift);
|
|
timespec64_add_ns(&tk->raw_time, nsec);
|
|
}
|
|
|
|
/**
|
|
* __getnstimeofday64 - Returns the time of day in a timespec64.
|
|
* @ts: pointer to the timespec to be set
|
|
*
|
|
* Updates the time of day in the timespec.
|
|
* Returns 0 on success, or -ve when suspended (timespec will be undefined).
|
|
*/
|
|
int __getnstimeofday64(struct timespec64 *ts)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned long seq;
|
|
s64 nsecs = 0;
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
|
|
ts->tv_sec = tk->xtime_sec;
|
|
nsecs = timekeeping_get_ns(&tk->tkr_mono);
|
|
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
ts->tv_nsec = 0;
|
|
timespec64_add_ns(ts, nsecs);
|
|
|
|
/*
|
|
* Do not bail out early, in case there were callers still using
|
|
* the value, even in the face of the WARN_ON.
|
|
*/
|
|
if (unlikely(timekeeping_suspended))
|
|
return -EAGAIN;
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(__getnstimeofday64);
|
|
|
|
/**
|
|
* getnstimeofday64 - Returns the time of day in a timespec64.
|
|
* @ts: pointer to the timespec64 to be set
|
|
*
|
|
* Returns the time of day in a timespec64 (WARN if suspended).
|
|
*/
|
|
void getnstimeofday64(struct timespec64 *ts)
|
|
{
|
|
WARN_ON(__getnstimeofday64(ts));
|
|
}
|
|
EXPORT_SYMBOL(getnstimeofday64);
|
|
|
|
ktime_t ktime_get(void)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned int seq;
|
|
ktime_t base;
|
|
s64 nsecs;
|
|
|
|
WARN_ON(timekeeping_suspended);
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
base = tk->tkr_mono.base;
|
|
nsecs = timekeeping_get_ns(&tk->tkr_mono);
|
|
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
return ktime_add_ns(base, nsecs);
|
|
}
|
|
EXPORT_SYMBOL_GPL(ktime_get);
|
|
|
|
u32 ktime_get_resolution_ns(void)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned int seq;
|
|
u32 nsecs;
|
|
|
|
WARN_ON(timekeeping_suspended);
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
nsecs = tk->tkr_mono.mult >> tk->tkr_mono.shift;
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
return nsecs;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ktime_get_resolution_ns);
|
|
|
|
static ktime_t *offsets[TK_OFFS_MAX] = {
|
|
[TK_OFFS_REAL] = &tk_core.timekeeper.offs_real,
|
|
[TK_OFFS_BOOT] = &tk_core.timekeeper.offs_boot,
|
|
[TK_OFFS_TAI] = &tk_core.timekeeper.offs_tai,
|
|
};
|
|
|
|
ktime_t ktime_get_with_offset(enum tk_offsets offs)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned int seq;
|
|
ktime_t base, *offset = offsets[offs];
|
|
s64 nsecs;
|
|
|
|
WARN_ON(timekeeping_suspended);
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
base = ktime_add(tk->tkr_mono.base, *offset);
|
|
nsecs = timekeeping_get_ns(&tk->tkr_mono);
|
|
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
return ktime_add_ns(base, nsecs);
|
|
|
|
}
|
|
EXPORT_SYMBOL_GPL(ktime_get_with_offset);
|
|
|
|
/**
|
|
* ktime_mono_to_any() - convert mononotic time to any other time
|
|
* @tmono: time to convert.
|
|
* @offs: which offset to use
|
|
*/
|
|
ktime_t ktime_mono_to_any(ktime_t tmono, enum tk_offsets offs)
|
|
{
|
|
ktime_t *offset = offsets[offs];
|
|
unsigned long seq;
|
|
ktime_t tconv;
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
tconv = ktime_add(tmono, *offset);
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
return tconv;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ktime_mono_to_any);
|
|
|
|
/**
|
|
* ktime_get_raw - Returns the raw monotonic time in ktime_t format
|
|
*/
|
|
ktime_t ktime_get_raw(void)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned int seq;
|
|
ktime_t base;
|
|
s64 nsecs;
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
base = tk->tkr_raw.base;
|
|
nsecs = timekeeping_get_ns(&tk->tkr_raw);
|
|
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
return ktime_add_ns(base, nsecs);
|
|
}
|
|
EXPORT_SYMBOL_GPL(ktime_get_raw);
|
|
|
|
/**
|
|
* ktime_get_ts64 - get the monotonic clock in timespec64 format
|
|
* @ts: pointer to timespec variable
|
|
*
|
|
* The function calculates the monotonic clock from the realtime
|
|
* clock and the wall_to_monotonic offset and stores the result
|
|
* in normalized timespec64 format in the variable pointed to by @ts.
|
|
*/
|
|
void ktime_get_ts64(struct timespec64 *ts)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
struct timespec64 tomono;
|
|
s64 nsec;
|
|
unsigned int seq;
|
|
|
|
WARN_ON(timekeeping_suspended);
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
ts->tv_sec = tk->xtime_sec;
|
|
nsec = timekeeping_get_ns(&tk->tkr_mono);
|
|
tomono = tk->wall_to_monotonic;
|
|
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
ts->tv_sec += tomono.tv_sec;
|
|
ts->tv_nsec = 0;
|
|
timespec64_add_ns(ts, nsec + tomono.tv_nsec);
|
|
}
|
|
EXPORT_SYMBOL_GPL(ktime_get_ts64);
|
|
|
|
/**
|
|
* ktime_get_seconds - Get the seconds portion of CLOCK_MONOTONIC
|
|
*
|
|
* Returns the seconds portion of CLOCK_MONOTONIC with a single non
|
|
* serialized read. tk->ktime_sec is of type 'unsigned long' so this
|
|
* works on both 32 and 64 bit systems. On 32 bit systems the readout
|
|
* covers ~136 years of uptime which should be enough to prevent
|
|
* premature wrap arounds.
|
|
*/
|
|
time64_t ktime_get_seconds(void)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
|
|
WARN_ON(timekeeping_suspended);
|
|
return tk->ktime_sec;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ktime_get_seconds);
|
|
|
|
/**
|
|
* ktime_get_real_seconds - Get the seconds portion of CLOCK_REALTIME
|
|
*
|
|
* Returns the wall clock seconds since 1970. This replaces the
|
|
* get_seconds() interface which is not y2038 safe on 32bit systems.
|
|
*
|
|
* For 64bit systems the fast access to tk->xtime_sec is preserved. On
|
|
* 32bit systems the access must be protected with the sequence
|
|
* counter to provide "atomic" access to the 64bit tk->xtime_sec
|
|
* value.
|
|
*/
|
|
time64_t ktime_get_real_seconds(void)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
time64_t seconds;
|
|
unsigned int seq;
|
|
|
|
if (IS_ENABLED(CONFIG_64BIT))
|
|
return tk->xtime_sec;
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
seconds = tk->xtime_sec;
|
|
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
return seconds;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ktime_get_real_seconds);
|
|
|
|
#ifdef CONFIG_NTP_PPS
|
|
|
|
/**
|
|
* ktime_get_raw_and_real_ts64 - get day and raw monotonic time in timespec format
|
|
* @ts_raw: pointer to the timespec to be set to raw monotonic time
|
|
* @ts_real: pointer to the timespec to be set to the time of day
|
|
*
|
|
* This function reads both the time of day and raw monotonic time at the
|
|
* same time atomically and stores the resulting timestamps in timespec
|
|
* format.
|
|
*/
|
|
void ktime_get_raw_and_real_ts64(struct timespec64 *ts_raw, struct timespec64 *ts_real)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned long seq;
|
|
s64 nsecs_raw, nsecs_real;
|
|
|
|
WARN_ON_ONCE(timekeeping_suspended);
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
|
|
*ts_raw = tk->raw_time;
|
|
ts_real->tv_sec = tk->xtime_sec;
|
|
ts_real->tv_nsec = 0;
|
|
|
|
nsecs_raw = timekeeping_get_ns(&tk->tkr_raw);
|
|
nsecs_real = timekeeping_get_ns(&tk->tkr_mono);
|
|
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
timespec64_add_ns(ts_raw, nsecs_raw);
|
|
timespec64_add_ns(ts_real, nsecs_real);
|
|
}
|
|
EXPORT_SYMBOL(ktime_get_raw_and_real_ts64);
|
|
|
|
#endif /* CONFIG_NTP_PPS */
|
|
|
|
/**
|
|
* do_gettimeofday - Returns the time of day in a timeval
|
|
* @tv: pointer to the timeval to be set
|
|
*
|
|
* NOTE: Users should be converted to using getnstimeofday()
|
|
*/
|
|
void do_gettimeofday(struct timeval *tv)
|
|
{
|
|
struct timespec64 now;
|
|
|
|
getnstimeofday64(&now);
|
|
tv->tv_sec = now.tv_sec;
|
|
tv->tv_usec = now.tv_nsec/1000;
|
|
}
|
|
EXPORT_SYMBOL(do_gettimeofday);
|
|
|
|
/**
|
|
* do_settimeofday64 - Sets the time of day.
|
|
* @ts: pointer to the timespec64 variable containing the new time
|
|
*
|
|
* Sets the time of day to the new time and update NTP and notify hrtimers
|
|
*/
|
|
int do_settimeofday64(const struct timespec64 *ts)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
struct timespec64 ts_delta, xt;
|
|
unsigned long flags;
|
|
int ret = 0;
|
|
|
|
if (!timespec64_valid_strict(ts))
|
|
return -EINVAL;
|
|
|
|
raw_spin_lock_irqsave(&timekeeper_lock, flags);
|
|
write_seqcount_begin(&tk_core.seq);
|
|
|
|
timekeeping_forward_now(tk);
|
|
|
|
xt = tk_xtime(tk);
|
|
ts_delta.tv_sec = ts->tv_sec - xt.tv_sec;
|
|
ts_delta.tv_nsec = ts->tv_nsec - xt.tv_nsec;
|
|
|
|
if (timespec64_compare(&tk->wall_to_monotonic, &ts_delta) > 0) {
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
tk_set_wall_to_mono(tk, timespec64_sub(tk->wall_to_monotonic, ts_delta));
|
|
|
|
tk_set_xtime(tk, ts);
|
|
out:
|
|
timekeeping_update(tk, TK_CLEAR_NTP | TK_MIRROR | TK_CLOCK_WAS_SET);
|
|
|
|
write_seqcount_end(&tk_core.seq);
|
|
raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
|
|
|
|
/* signal hrtimers about time change */
|
|
clock_was_set();
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(do_settimeofday64);
|
|
|
|
/**
|
|
* timekeeping_inject_offset - Adds or subtracts from the current time.
|
|
* @tv: pointer to the timespec variable containing the offset
|
|
*
|
|
* Adds or subtracts an offset value from the current time.
|
|
*/
|
|
int timekeeping_inject_offset(struct timespec *ts)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned long flags;
|
|
struct timespec64 ts64, tmp;
|
|
int ret = 0;
|
|
|
|
if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
|
|
return -EINVAL;
|
|
|
|
ts64 = timespec_to_timespec64(*ts);
|
|
|
|
raw_spin_lock_irqsave(&timekeeper_lock, flags);
|
|
write_seqcount_begin(&tk_core.seq);
|
|
|
|
timekeeping_forward_now(tk);
|
|
|
|
/* Make sure the proposed value is valid */
|
|
tmp = timespec64_add(tk_xtime(tk), ts64);
|
|
if (timespec64_compare(&tk->wall_to_monotonic, &ts64) > 0 ||
|
|
!timespec64_valid_strict(&tmp)) {
|
|
ret = -EINVAL;
|
|
goto error;
|
|
}
|
|
|
|
tk_xtime_add(tk, &ts64);
|
|
tk_set_wall_to_mono(tk, timespec64_sub(tk->wall_to_monotonic, ts64));
|
|
|
|
error: /* even if we error out, we forwarded the time, so call update */
|
|
timekeeping_update(tk, TK_CLEAR_NTP | TK_MIRROR | TK_CLOCK_WAS_SET);
|
|
|
|
write_seqcount_end(&tk_core.seq);
|
|
raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
|
|
|
|
/* signal hrtimers about time change */
|
|
clock_was_set();
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(timekeeping_inject_offset);
|
|
|
|
|
|
/**
|
|
* timekeeping_get_tai_offset - Returns current TAI offset from UTC
|
|
*
|
|
*/
|
|
s32 timekeeping_get_tai_offset(void)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned int seq;
|
|
s32 ret;
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
ret = tk->tai_offset;
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* __timekeeping_set_tai_offset - Lock free worker function
|
|
*
|
|
*/
|
|
static void __timekeeping_set_tai_offset(struct timekeeper *tk, s32 tai_offset)
|
|
{
|
|
tk->tai_offset = tai_offset;
|
|
tk->offs_tai = ktime_add(tk->offs_real, ktime_set(tai_offset, 0));
|
|
}
|
|
|
|
/**
|
|
* timekeeping_set_tai_offset - Sets the current TAI offset from UTC
|
|
*
|
|
*/
|
|
void timekeeping_set_tai_offset(s32 tai_offset)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned long flags;
|
|
|
|
raw_spin_lock_irqsave(&timekeeper_lock, flags);
|
|
write_seqcount_begin(&tk_core.seq);
|
|
__timekeeping_set_tai_offset(tk, tai_offset);
|
|
timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET);
|
|
write_seqcount_end(&tk_core.seq);
|
|
raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
|
|
clock_was_set();
|
|
}
|
|
|
|
/**
|
|
* change_clocksource - Swaps clocksources if a new one is available
|
|
*
|
|
* Accumulates current time interval and initializes new clocksource
|
|
*/
|
|
static int change_clocksource(void *data)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
struct clocksource *new, *old;
|
|
unsigned long flags;
|
|
|
|
new = (struct clocksource *) data;
|
|
|
|
raw_spin_lock_irqsave(&timekeeper_lock, flags);
|
|
write_seqcount_begin(&tk_core.seq);
|
|
|
|
timekeeping_forward_now(tk);
|
|
/*
|
|
* If the cs is in module, get a module reference. Succeeds
|
|
* for built-in code (owner == NULL) as well.
|
|
*/
|
|
if (try_module_get(new->owner)) {
|
|
if (!new->enable || new->enable(new) == 0) {
|
|
old = tk->tkr_mono.clock;
|
|
tk_setup_internals(tk, new);
|
|
if (old->disable)
|
|
old->disable(old);
|
|
module_put(old->owner);
|
|
} else {
|
|
module_put(new->owner);
|
|
}
|
|
}
|
|
timekeeping_update(tk, TK_CLEAR_NTP | TK_MIRROR | TK_CLOCK_WAS_SET);
|
|
|
|
write_seqcount_end(&tk_core.seq);
|
|
raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* timekeeping_notify - Install a new clock source
|
|
* @clock: pointer to the clock source
|
|
*
|
|
* This function is called from clocksource.c after a new, better clock
|
|
* source has been registered. The caller holds the clocksource_mutex.
|
|
*/
|
|
int timekeeping_notify(struct clocksource *clock)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
|
|
if (tk->tkr_mono.clock == clock)
|
|
return 0;
|
|
stop_machine(change_clocksource, clock, NULL);
|
|
tick_clock_notify();
|
|
return tk->tkr_mono.clock == clock ? 0 : -1;
|
|
}
|
|
|
|
/**
|
|
* getrawmonotonic64 - Returns the raw monotonic time in a timespec
|
|
* @ts: pointer to the timespec64 to be set
|
|
*
|
|
* Returns the raw monotonic time (completely un-modified by ntp)
|
|
*/
|
|
void getrawmonotonic64(struct timespec64 *ts)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
struct timespec64 ts64;
|
|
unsigned long seq;
|
|
s64 nsecs;
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
nsecs = timekeeping_get_ns(&tk->tkr_raw);
|
|
ts64 = tk->raw_time;
|
|
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
timespec64_add_ns(&ts64, nsecs);
|
|
*ts = ts64;
|
|
}
|
|
EXPORT_SYMBOL(getrawmonotonic64);
|
|
|
|
|
|
/**
|
|
* timekeeping_valid_for_hres - Check if timekeeping is suitable for hres
|
|
*/
|
|
int timekeeping_valid_for_hres(void)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned long seq;
|
|
int ret;
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
|
|
ret = tk->tkr_mono.clock->flags & CLOCK_SOURCE_VALID_FOR_HRES;
|
|
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* timekeeping_max_deferment - Returns max time the clocksource can be deferred
|
|
*/
|
|
u64 timekeeping_max_deferment(void)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned long seq;
|
|
u64 ret;
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
|
|
ret = tk->tkr_mono.clock->max_idle_ns;
|
|
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* read_persistent_clock - Return time from the persistent clock.
|
|
*
|
|
* Weak dummy function for arches that do not yet support it.
|
|
* Reads the time from the battery backed persistent clock.
|
|
* Returns a timespec with tv_sec=0 and tv_nsec=0 if unsupported.
|
|
*
|
|
* XXX - Do be sure to remove it once all arches implement it.
|
|
*/
|
|
void __weak read_persistent_clock(struct timespec *ts)
|
|
{
|
|
ts->tv_sec = 0;
|
|
ts->tv_nsec = 0;
|
|
}
|
|
|
|
void __weak read_persistent_clock64(struct timespec64 *ts64)
|
|
{
|
|
struct timespec ts;
|
|
|
|
read_persistent_clock(&ts);
|
|
*ts64 = timespec_to_timespec64(ts);
|
|
}
|
|
|
|
/**
|
|
* read_boot_clock64 - Return time of the system start.
|
|
*
|
|
* Weak dummy function for arches that do not yet support it.
|
|
* Function to read the exact time the system has been started.
|
|
* Returns a timespec64 with tv_sec=0 and tv_nsec=0 if unsupported.
|
|
*
|
|
* XXX - Do be sure to remove it once all arches implement it.
|
|
*/
|
|
void __weak read_boot_clock64(struct timespec64 *ts)
|
|
{
|
|
ts->tv_sec = 0;
|
|
ts->tv_nsec = 0;
|
|
}
|
|
|
|
/* Flag for if timekeeping_resume() has injected sleeptime */
|
|
static bool sleeptime_injected;
|
|
|
|
/* Flag for if there is a persistent clock on this platform */
|
|
static bool persistent_clock_exists;
|
|
|
|
/*
|
|
* timekeeping_init - Initializes the clocksource and common timekeeping values
|
|
*/
|
|
void __init timekeeping_init(void)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
struct clocksource *clock;
|
|
unsigned long flags;
|
|
struct timespec64 now, boot, tmp;
|
|
|
|
read_persistent_clock64(&now);
|
|
if (!timespec64_valid_strict(&now)) {
|
|
pr_warn("WARNING: Persistent clock returned invalid value!\n"
|
|
" Check your CMOS/BIOS settings.\n");
|
|
now.tv_sec = 0;
|
|
now.tv_nsec = 0;
|
|
} else if (now.tv_sec || now.tv_nsec)
|
|
persistent_clock_exists = true;
|
|
|
|
read_boot_clock64(&boot);
|
|
if (!timespec64_valid_strict(&boot)) {
|
|
pr_warn("WARNING: Boot clock returned invalid value!\n"
|
|
" Check your CMOS/BIOS settings.\n");
|
|
boot.tv_sec = 0;
|
|
boot.tv_nsec = 0;
|
|
}
|
|
|
|
raw_spin_lock_irqsave(&timekeeper_lock, flags);
|
|
write_seqcount_begin(&tk_core.seq);
|
|
ntp_init();
|
|
|
|
clock = clocksource_default_clock();
|
|
if (clock->enable)
|
|
clock->enable(clock);
|
|
tk_setup_internals(tk, clock);
|
|
|
|
tk_set_xtime(tk, &now);
|
|
tk->raw_time.tv_sec = 0;
|
|
tk->raw_time.tv_nsec = 0;
|
|
if (boot.tv_sec == 0 && boot.tv_nsec == 0)
|
|
boot = tk_xtime(tk);
|
|
|
|
set_normalized_timespec64(&tmp, -boot.tv_sec, -boot.tv_nsec);
|
|
tk_set_wall_to_mono(tk, tmp);
|
|
|
|
timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET);
|
|
|
|
write_seqcount_end(&tk_core.seq);
|
|
raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
|
|
}
|
|
|
|
/* time in seconds when suspend began for persistent clock */
|
|
static struct timespec64 timekeeping_suspend_time;
|
|
|
|
/**
|
|
* __timekeeping_inject_sleeptime - Internal function to add sleep interval
|
|
* @delta: pointer to a timespec delta value
|
|
*
|
|
* Takes a timespec offset measuring a suspend interval and properly
|
|
* adds the sleep offset to the timekeeping variables.
|
|
*/
|
|
static void __timekeeping_inject_sleeptime(struct timekeeper *tk,
|
|
struct timespec64 *delta)
|
|
{
|
|
if (!timespec64_valid_strict(delta)) {
|
|
printk_deferred(KERN_WARNING
|
|
"__timekeeping_inject_sleeptime: Invalid "
|
|
"sleep delta value!\n");
|
|
return;
|
|
}
|
|
tk_xtime_add(tk, delta);
|
|
tk_set_wall_to_mono(tk, timespec64_sub(tk->wall_to_monotonic, *delta));
|
|
tk_update_sleep_time(tk, timespec64_to_ktime(*delta));
|
|
tk_debug_account_sleep_time(delta);
|
|
}
|
|
|
|
#if defined(CONFIG_PM_SLEEP) && defined(CONFIG_RTC_HCTOSYS_DEVICE)
|
|
/**
|
|
* We have three kinds of time sources to use for sleep time
|
|
* injection, the preference order is:
|
|
* 1) non-stop clocksource
|
|
* 2) persistent clock (ie: RTC accessible when irqs are off)
|
|
* 3) RTC
|
|
*
|
|
* 1) and 2) are used by timekeeping, 3) by RTC subsystem.
|
|
* If system has neither 1) nor 2), 3) will be used finally.
|
|
*
|
|
*
|
|
* If timekeeping has injected sleeptime via either 1) or 2),
|
|
* 3) becomes needless, so in this case we don't need to call
|
|
* rtc_resume(), and this is what timekeeping_rtc_skipresume()
|
|
* means.
|
|
*/
|
|
bool timekeeping_rtc_skipresume(void)
|
|
{
|
|
return sleeptime_injected;
|
|
}
|
|
|
|
/**
|
|
* 1) can be determined whether to use or not only when doing
|
|
* timekeeping_resume() which is invoked after rtc_suspend(),
|
|
* so we can't skip rtc_suspend() surely if system has 1).
|
|
*
|
|
* But if system has 2), 2) will definitely be used, so in this
|
|
* case we don't need to call rtc_suspend(), and this is what
|
|
* timekeeping_rtc_skipsuspend() means.
|
|
*/
|
|
bool timekeeping_rtc_skipsuspend(void)
|
|
{
|
|
return persistent_clock_exists;
|
|
}
|
|
|
|
/**
|
|
* timekeeping_inject_sleeptime64 - Adds suspend interval to timeekeeping values
|
|
* @delta: pointer to a timespec64 delta value
|
|
*
|
|
* This hook is for architectures that cannot support read_persistent_clock64
|
|
* because their RTC/persistent clock is only accessible when irqs are enabled.
|
|
* and also don't have an effective nonstop clocksource.
|
|
*
|
|
* This function should only be called by rtc_resume(), and allows
|
|
* a suspend offset to be injected into the timekeeping values.
|
|
*/
|
|
void timekeeping_inject_sleeptime64(struct timespec64 *delta)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned long flags;
|
|
|
|
raw_spin_lock_irqsave(&timekeeper_lock, flags);
|
|
write_seqcount_begin(&tk_core.seq);
|
|
|
|
timekeeping_forward_now(tk);
|
|
|
|
__timekeeping_inject_sleeptime(tk, delta);
|
|
|
|
timekeeping_update(tk, TK_CLEAR_NTP | TK_MIRROR | TK_CLOCK_WAS_SET);
|
|
|
|
write_seqcount_end(&tk_core.seq);
|
|
raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
|
|
|
|
/* signal hrtimers about time change */
|
|
clock_was_set();
|
|
}
|
|
#endif
|
|
|
|
/**
|
|
* timekeeping_resume - Resumes the generic timekeeping subsystem.
|
|
*/
|
|
void timekeeping_resume(void)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
struct clocksource *clock = tk->tkr_mono.clock;
|
|
unsigned long flags;
|
|
struct timespec64 ts_new, ts_delta;
|
|
cycle_t cycle_now, cycle_delta;
|
|
|
|
sleeptime_injected = false;
|
|
read_persistent_clock64(&ts_new);
|
|
|
|
clockevents_resume();
|
|
clocksource_resume();
|
|
|
|
raw_spin_lock_irqsave(&timekeeper_lock, flags);
|
|
write_seqcount_begin(&tk_core.seq);
|
|
|
|
/*
|
|
* After system resumes, we need to calculate the suspended time and
|
|
* compensate it for the OS time. There are 3 sources that could be
|
|
* used: Nonstop clocksource during suspend, persistent clock and rtc
|
|
* device.
|
|
*
|
|
* One specific platform may have 1 or 2 or all of them, and the
|
|
* preference will be:
|
|
* suspend-nonstop clocksource -> persistent clock -> rtc
|
|
* The less preferred source will only be tried if there is no better
|
|
* usable source. The rtc part is handled separately in rtc core code.
|
|
*/
|
|
cycle_now = tk->tkr_mono.read(clock);
|
|
if ((clock->flags & CLOCK_SOURCE_SUSPEND_NONSTOP) &&
|
|
cycle_now > tk->tkr_mono.cycle_last) {
|
|
u64 num, max = ULLONG_MAX;
|
|
u32 mult = clock->mult;
|
|
u32 shift = clock->shift;
|
|
s64 nsec = 0;
|
|
|
|
cycle_delta = clocksource_delta(cycle_now, tk->tkr_mono.cycle_last,
|
|
tk->tkr_mono.mask);
|
|
|
|
/*
|
|
* "cycle_delta * mutl" may cause 64 bits overflow, if the
|
|
* suspended time is too long. In that case we need do the
|
|
* 64 bits math carefully
|
|
*/
|
|
do_div(max, mult);
|
|
if (cycle_delta > max) {
|
|
num = div64_u64(cycle_delta, max);
|
|
nsec = (((u64) max * mult) >> shift) * num;
|
|
cycle_delta -= num * max;
|
|
}
|
|
nsec += ((u64) cycle_delta * mult) >> shift;
|
|
|
|
ts_delta = ns_to_timespec64(nsec);
|
|
sleeptime_injected = true;
|
|
} else if (timespec64_compare(&ts_new, &timekeeping_suspend_time) > 0) {
|
|
ts_delta = timespec64_sub(ts_new, timekeeping_suspend_time);
|
|
sleeptime_injected = true;
|
|
}
|
|
|
|
if (sleeptime_injected)
|
|
__timekeeping_inject_sleeptime(tk, &ts_delta);
|
|
|
|
/* Re-base the last cycle value */
|
|
tk->tkr_mono.cycle_last = cycle_now;
|
|
tk->tkr_raw.cycle_last = cycle_now;
|
|
|
|
tk->ntp_error = 0;
|
|
timekeeping_suspended = 0;
|
|
timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET);
|
|
write_seqcount_end(&tk_core.seq);
|
|
raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
|
|
|
|
touch_softlockup_watchdog();
|
|
|
|
tick_resume();
|
|
hrtimers_resume();
|
|
}
|
|
|
|
int timekeeping_suspend(void)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned long flags;
|
|
struct timespec64 delta, delta_delta;
|
|
static struct timespec64 old_delta;
|
|
|
|
read_persistent_clock64(&timekeeping_suspend_time);
|
|
|
|
/*
|
|
* On some systems the persistent_clock can not be detected at
|
|
* timekeeping_init by its return value, so if we see a valid
|
|
* value returned, update the persistent_clock_exists flag.
|
|
*/
|
|
if (timekeeping_suspend_time.tv_sec || timekeeping_suspend_time.tv_nsec)
|
|
persistent_clock_exists = true;
|
|
|
|
raw_spin_lock_irqsave(&timekeeper_lock, flags);
|
|
write_seqcount_begin(&tk_core.seq);
|
|
timekeeping_forward_now(tk);
|
|
timekeeping_suspended = 1;
|
|
|
|
if (persistent_clock_exists) {
|
|
/*
|
|
* To avoid drift caused by repeated suspend/resumes,
|
|
* which each can add ~1 second drift error,
|
|
* try to compensate so the difference in system time
|
|
* and persistent_clock time stays close to constant.
|
|
*/
|
|
delta = timespec64_sub(tk_xtime(tk), timekeeping_suspend_time);
|
|
delta_delta = timespec64_sub(delta, old_delta);
|
|
if (abs(delta_delta.tv_sec) >= 2) {
|
|
/*
|
|
* if delta_delta is too large, assume time correction
|
|
* has occurred and set old_delta to the current delta.
|
|
*/
|
|
old_delta = delta;
|
|
} else {
|
|
/* Otherwise try to adjust old_system to compensate */
|
|
timekeeping_suspend_time =
|
|
timespec64_add(timekeeping_suspend_time, delta_delta);
|
|
}
|
|
}
|
|
|
|
timekeeping_update(tk, TK_MIRROR);
|
|
halt_fast_timekeeper(tk);
|
|
write_seqcount_end(&tk_core.seq);
|
|
raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
|
|
|
|
tick_suspend();
|
|
clocksource_suspend();
|
|
clockevents_suspend();
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* sysfs resume/suspend bits for timekeeping */
|
|
static struct syscore_ops timekeeping_syscore_ops = {
|
|
.resume = timekeeping_resume,
|
|
.suspend = timekeeping_suspend,
|
|
};
|
|
|
|
static int __init timekeeping_init_ops(void)
|
|
{
|
|
register_syscore_ops(&timekeeping_syscore_ops);
|
|
return 0;
|
|
}
|
|
device_initcall(timekeeping_init_ops);
|
|
|
|
/*
|
|
* Apply a multiplier adjustment to the timekeeper
|
|
*/
|
|
static __always_inline void timekeeping_apply_adjustment(struct timekeeper *tk,
|
|
s64 offset,
|
|
bool negative,
|
|
int adj_scale)
|
|
{
|
|
s64 interval = tk->cycle_interval;
|
|
s32 mult_adj = 1;
|
|
|
|
if (negative) {
|
|
mult_adj = -mult_adj;
|
|
interval = -interval;
|
|
offset = -offset;
|
|
}
|
|
mult_adj <<= adj_scale;
|
|
interval <<= adj_scale;
|
|
offset <<= adj_scale;
|
|
|
|
/*
|
|
* So the following can be confusing.
|
|
*
|
|
* To keep things simple, lets assume mult_adj == 1 for now.
|
|
*
|
|
* When mult_adj != 1, remember that the interval and offset values
|
|
* have been appropriately scaled so the math is the same.
|
|
*
|
|
* The basic idea here is that we're increasing the multiplier
|
|
* by one, this causes the xtime_interval to be incremented by
|
|
* one cycle_interval. This is because:
|
|
* xtime_interval = cycle_interval * mult
|
|
* So if mult is being incremented by one:
|
|
* xtime_interval = cycle_interval * (mult + 1)
|
|
* Its the same as:
|
|
* xtime_interval = (cycle_interval * mult) + cycle_interval
|
|
* Which can be shortened to:
|
|
* xtime_interval += cycle_interval
|
|
*
|
|
* So offset stores the non-accumulated cycles. Thus the current
|
|
* time (in shifted nanoseconds) is:
|
|
* now = (offset * adj) + xtime_nsec
|
|
* Now, even though we're adjusting the clock frequency, we have
|
|
* to keep time consistent. In other words, we can't jump back
|
|
* in time, and we also want to avoid jumping forward in time.
|
|
*
|
|
* So given the same offset value, we need the time to be the same
|
|
* both before and after the freq adjustment.
|
|
* now = (offset * adj_1) + xtime_nsec_1
|
|
* now = (offset * adj_2) + xtime_nsec_2
|
|
* So:
|
|
* (offset * adj_1) + xtime_nsec_1 =
|
|
* (offset * adj_2) + xtime_nsec_2
|
|
* And we know:
|
|
* adj_2 = adj_1 + 1
|
|
* So:
|
|
* (offset * adj_1) + xtime_nsec_1 =
|
|
* (offset * (adj_1+1)) + xtime_nsec_2
|
|
* (offset * adj_1) + xtime_nsec_1 =
|
|
* (offset * adj_1) + offset + xtime_nsec_2
|
|
* Canceling the sides:
|
|
* xtime_nsec_1 = offset + xtime_nsec_2
|
|
* Which gives us:
|
|
* xtime_nsec_2 = xtime_nsec_1 - offset
|
|
* Which simplfies to:
|
|
* xtime_nsec -= offset
|
|
*
|
|
* XXX - TODO: Doc ntp_error calculation.
|
|
*/
|
|
if ((mult_adj > 0) && (tk->tkr_mono.mult + mult_adj < mult_adj)) {
|
|
/* NTP adjustment caused clocksource mult overflow */
|
|
WARN_ON_ONCE(1);
|
|
return;
|
|
}
|
|
|
|
tk->tkr_mono.mult += mult_adj;
|
|
tk->xtime_interval += interval;
|
|
tk->tkr_mono.xtime_nsec -= offset;
|
|
tk->ntp_error -= (interval - offset) << tk->ntp_error_shift;
|
|
}
|
|
|
|
/*
|
|
* Calculate the multiplier adjustment needed to match the frequency
|
|
* specified by NTP
|
|
*/
|
|
static __always_inline void timekeeping_freqadjust(struct timekeeper *tk,
|
|
s64 offset)
|
|
{
|
|
s64 interval = tk->cycle_interval;
|
|
s64 xinterval = tk->xtime_interval;
|
|
s64 tick_error;
|
|
bool negative;
|
|
u32 adj;
|
|
|
|
/* Remove any current error adj from freq calculation */
|
|
if (tk->ntp_err_mult)
|
|
xinterval -= tk->cycle_interval;
|
|
|
|
tk->ntp_tick = ntp_tick_length();
|
|
|
|
/* Calculate current error per tick */
|
|
tick_error = ntp_tick_length() >> tk->ntp_error_shift;
|
|
tick_error -= (xinterval + tk->xtime_remainder);
|
|
|
|
/* Don't worry about correcting it if its small */
|
|
if (likely((tick_error >= 0) && (tick_error <= interval)))
|
|
return;
|
|
|
|
/* preserve the direction of correction */
|
|
negative = (tick_error < 0);
|
|
|
|
/* Sort out the magnitude of the correction */
|
|
tick_error = abs(tick_error);
|
|
for (adj = 0; tick_error > interval; adj++)
|
|
tick_error >>= 1;
|
|
|
|
/* scale the corrections */
|
|
timekeeping_apply_adjustment(tk, offset, negative, adj);
|
|
}
|
|
|
|
/*
|
|
* Adjust the timekeeper's multiplier to the correct frequency
|
|
* and also to reduce the accumulated error value.
|
|
*/
|
|
static void timekeeping_adjust(struct timekeeper *tk, s64 offset)
|
|
{
|
|
/* Correct for the current frequency error */
|
|
timekeeping_freqadjust(tk, offset);
|
|
|
|
/* Next make a small adjustment to fix any cumulative error */
|
|
if (!tk->ntp_err_mult && (tk->ntp_error > 0)) {
|
|
tk->ntp_err_mult = 1;
|
|
timekeeping_apply_adjustment(tk, offset, 0, 0);
|
|
} else if (tk->ntp_err_mult && (tk->ntp_error <= 0)) {
|
|
/* Undo any existing error adjustment */
|
|
timekeeping_apply_adjustment(tk, offset, 1, 0);
|
|
tk->ntp_err_mult = 0;
|
|
}
|
|
|
|
if (unlikely(tk->tkr_mono.clock->maxadj &&
|
|
(abs(tk->tkr_mono.mult - tk->tkr_mono.clock->mult)
|
|
> tk->tkr_mono.clock->maxadj))) {
|
|
printk_once(KERN_WARNING
|
|
"Adjusting %s more than 11%% (%ld vs %ld)\n",
|
|
tk->tkr_mono.clock->name, (long)tk->tkr_mono.mult,
|
|
(long)tk->tkr_mono.clock->mult + tk->tkr_mono.clock->maxadj);
|
|
}
|
|
|
|
/*
|
|
* It may be possible that when we entered this function, xtime_nsec
|
|
* was very small. Further, if we're slightly speeding the clocksource
|
|
* in the code above, its possible the required corrective factor to
|
|
* xtime_nsec could cause it to underflow.
|
|
*
|
|
* Now, since we already accumulated the second, cannot simply roll
|
|
* the accumulated second back, since the NTP subsystem has been
|
|
* notified via second_overflow. So instead we push xtime_nsec forward
|
|
* by the amount we underflowed, and add that amount into the error.
|
|
*
|
|
* We'll correct this error next time through this function, when
|
|
* xtime_nsec is not as small.
|
|
*/
|
|
if (unlikely((s64)tk->tkr_mono.xtime_nsec < 0)) {
|
|
s64 neg = -(s64)tk->tkr_mono.xtime_nsec;
|
|
tk->tkr_mono.xtime_nsec = 0;
|
|
tk->ntp_error += neg << tk->ntp_error_shift;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* accumulate_nsecs_to_secs - Accumulates nsecs into secs
|
|
*
|
|
* Helper function that accumulates the nsecs greater than a second
|
|
* from the xtime_nsec field to the xtime_secs field.
|
|
* It also calls into the NTP code to handle leapsecond processing.
|
|
*
|
|
*/
|
|
static inline unsigned int accumulate_nsecs_to_secs(struct timekeeper *tk)
|
|
{
|
|
u64 nsecps = (u64)NSEC_PER_SEC << tk->tkr_mono.shift;
|
|
unsigned int clock_set = 0;
|
|
|
|
while (tk->tkr_mono.xtime_nsec >= nsecps) {
|
|
int leap;
|
|
|
|
tk->tkr_mono.xtime_nsec -= nsecps;
|
|
tk->xtime_sec++;
|
|
|
|
/* Figure out if its a leap sec and apply if needed */
|
|
leap = second_overflow(tk->xtime_sec);
|
|
if (unlikely(leap)) {
|
|
struct timespec64 ts;
|
|
|
|
tk->xtime_sec += leap;
|
|
|
|
ts.tv_sec = leap;
|
|
ts.tv_nsec = 0;
|
|
tk_set_wall_to_mono(tk,
|
|
timespec64_sub(tk->wall_to_monotonic, ts));
|
|
|
|
__timekeeping_set_tai_offset(tk, tk->tai_offset - leap);
|
|
|
|
clock_set = TK_CLOCK_WAS_SET;
|
|
}
|
|
}
|
|
return clock_set;
|
|
}
|
|
|
|
/**
|
|
* logarithmic_accumulation - shifted accumulation of cycles
|
|
*
|
|
* This functions accumulates a shifted interval of cycles into
|
|
* into a shifted interval nanoseconds. Allows for O(log) accumulation
|
|
* loop.
|
|
*
|
|
* Returns the unconsumed cycles.
|
|
*/
|
|
static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset,
|
|
u32 shift,
|
|
unsigned int *clock_set)
|
|
{
|
|
cycle_t interval = tk->cycle_interval << shift;
|
|
u64 raw_nsecs;
|
|
|
|
/* If the offset is smaller than a shifted interval, do nothing */
|
|
if (offset < interval)
|
|
return offset;
|
|
|
|
/* Accumulate one shifted interval */
|
|
offset -= interval;
|
|
tk->tkr_mono.cycle_last += interval;
|
|
tk->tkr_raw.cycle_last += interval;
|
|
|
|
tk->tkr_mono.xtime_nsec += tk->xtime_interval << shift;
|
|
*clock_set |= accumulate_nsecs_to_secs(tk);
|
|
|
|
/* Accumulate raw time */
|
|
raw_nsecs = (u64)tk->raw_interval << shift;
|
|
raw_nsecs += tk->raw_time.tv_nsec;
|
|
if (raw_nsecs >= NSEC_PER_SEC) {
|
|
u64 raw_secs = raw_nsecs;
|
|
raw_nsecs = do_div(raw_secs, NSEC_PER_SEC);
|
|
tk->raw_time.tv_sec += raw_secs;
|
|
}
|
|
tk->raw_time.tv_nsec = raw_nsecs;
|
|
|
|
/* Accumulate error between NTP and clock interval */
|
|
tk->ntp_error += tk->ntp_tick << shift;
|
|
tk->ntp_error -= (tk->xtime_interval + tk->xtime_remainder) <<
|
|
(tk->ntp_error_shift + shift);
|
|
|
|
return offset;
|
|
}
|
|
|
|
/**
|
|
* update_wall_time - Uses the current clocksource to increment the wall time
|
|
*
|
|
*/
|
|
void update_wall_time(void)
|
|
{
|
|
struct timekeeper *real_tk = &tk_core.timekeeper;
|
|
struct timekeeper *tk = &shadow_timekeeper;
|
|
cycle_t offset;
|
|
int shift = 0, maxshift;
|
|
unsigned int clock_set = 0;
|
|
unsigned long flags;
|
|
|
|
raw_spin_lock_irqsave(&timekeeper_lock, flags);
|
|
|
|
/* Make sure we're fully resumed: */
|
|
if (unlikely(timekeeping_suspended))
|
|
goto out;
|
|
|
|
#ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
|
|
offset = real_tk->cycle_interval;
|
|
#else
|
|
offset = clocksource_delta(tk->tkr_mono.read(tk->tkr_mono.clock),
|
|
tk->tkr_mono.cycle_last, tk->tkr_mono.mask);
|
|
#endif
|
|
|
|
/* Check if there's really nothing to do */
|
|
if (offset < real_tk->cycle_interval)
|
|
goto out;
|
|
|
|
/* Do some additional sanity checking */
|
|
timekeeping_check_update(real_tk, offset);
|
|
|
|
/*
|
|
* With NO_HZ we may have to accumulate many cycle_intervals
|
|
* (think "ticks") worth of time at once. To do this efficiently,
|
|
* we calculate the largest doubling multiple of cycle_intervals
|
|
* that is smaller than the offset. We then accumulate that
|
|
* chunk in one go, and then try to consume the next smaller
|
|
* doubled multiple.
|
|
*/
|
|
shift = ilog2(offset) - ilog2(tk->cycle_interval);
|
|
shift = max(0, shift);
|
|
/* Bound shift to one less than what overflows tick_length */
|
|
maxshift = (64 - (ilog2(ntp_tick_length())+1)) - 1;
|
|
shift = min(shift, maxshift);
|
|
while (offset >= tk->cycle_interval) {
|
|
offset = logarithmic_accumulation(tk, offset, shift,
|
|
&clock_set);
|
|
if (offset < tk->cycle_interval<<shift)
|
|
shift--;
|
|
}
|
|
|
|
/* correct the clock when NTP error is too big */
|
|
timekeeping_adjust(tk, offset);
|
|
|
|
/*
|
|
* XXX This can be killed once everyone converts
|
|
* to the new update_vsyscall.
|
|
*/
|
|
old_vsyscall_fixup(tk);
|
|
|
|
/*
|
|
* Finally, make sure that after the rounding
|
|
* xtime_nsec isn't larger than NSEC_PER_SEC
|
|
*/
|
|
clock_set |= accumulate_nsecs_to_secs(tk);
|
|
|
|
write_seqcount_begin(&tk_core.seq);
|
|
/*
|
|
* Update the real timekeeper.
|
|
*
|
|
* We could avoid this memcpy by switching pointers, but that
|
|
* requires changes to all other timekeeper usage sites as
|
|
* well, i.e. move the timekeeper pointer getter into the
|
|
* spinlocked/seqcount protected sections. And we trade this
|
|
* memcpy under the tk_core.seq against one before we start
|
|
* updating.
|
|
*/
|
|
timekeeping_update(tk, clock_set);
|
|
memcpy(real_tk, tk, sizeof(*tk));
|
|
/* The memcpy must come last. Do not put anything here! */
|
|
write_seqcount_end(&tk_core.seq);
|
|
out:
|
|
raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
|
|
if (clock_set)
|
|
/* Have to call _delayed version, since in irq context*/
|
|
clock_was_set_delayed();
|
|
}
|
|
|
|
/**
|
|
* getboottime64 - Return the real time of system boot.
|
|
* @ts: pointer to the timespec64 to be set
|
|
*
|
|
* Returns the wall-time of boot in a timespec64.
|
|
*
|
|
* This is based on the wall_to_monotonic offset and the total suspend
|
|
* time. Calls to settimeofday will affect the value returned (which
|
|
* basically means that however wrong your real time clock is at boot time,
|
|
* you get the right time here).
|
|
*/
|
|
void getboottime64(struct timespec64 *ts)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
ktime_t t = ktime_sub(tk->offs_real, tk->offs_boot);
|
|
|
|
*ts = ktime_to_timespec64(t);
|
|
}
|
|
EXPORT_SYMBOL_GPL(getboottime64);
|
|
|
|
unsigned long get_seconds(void)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
|
|
return tk->xtime_sec;
|
|
}
|
|
EXPORT_SYMBOL(get_seconds);
|
|
|
|
struct timespec __current_kernel_time(void)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
|
|
return timespec64_to_timespec(tk_xtime(tk));
|
|
}
|
|
|
|
struct timespec64 current_kernel_time64(void)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
struct timespec64 now;
|
|
unsigned long seq;
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
|
|
now = tk_xtime(tk);
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
return now;
|
|
}
|
|
EXPORT_SYMBOL(current_kernel_time64);
|
|
|
|
struct timespec64 get_monotonic_coarse64(void)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
struct timespec64 now, mono;
|
|
unsigned long seq;
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
|
|
now = tk_xtime(tk);
|
|
mono = tk->wall_to_monotonic;
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
set_normalized_timespec64(&now, now.tv_sec + mono.tv_sec,
|
|
now.tv_nsec + mono.tv_nsec);
|
|
|
|
return now;
|
|
}
|
|
|
|
/*
|
|
* Must hold jiffies_lock
|
|
*/
|
|
void do_timer(unsigned long ticks)
|
|
{
|
|
jiffies_64 += ticks;
|
|
calc_global_load(ticks);
|
|
}
|
|
|
|
/**
|
|
* ktime_get_update_offsets_now - hrtimer helper
|
|
* @cwsseq: pointer to check and store the clock was set sequence number
|
|
* @offs_real: pointer to storage for monotonic -> realtime offset
|
|
* @offs_boot: pointer to storage for monotonic -> boottime offset
|
|
* @offs_tai: pointer to storage for monotonic -> clock tai offset
|
|
*
|
|
* Returns current monotonic time and updates the offsets if the
|
|
* sequence number in @cwsseq and timekeeper.clock_was_set_seq are
|
|
* different.
|
|
*
|
|
* Called from hrtimer_interrupt() or retrigger_next_event()
|
|
*/
|
|
ktime_t ktime_get_update_offsets_now(unsigned int *cwsseq, ktime_t *offs_real,
|
|
ktime_t *offs_boot, ktime_t *offs_tai)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned int seq;
|
|
ktime_t base;
|
|
u64 nsecs;
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&tk_core.seq);
|
|
|
|
base = tk->tkr_mono.base;
|
|
nsecs = timekeeping_get_ns(&tk->tkr_mono);
|
|
base = ktime_add_ns(base, nsecs);
|
|
|
|
if (*cwsseq != tk->clock_was_set_seq) {
|
|
*cwsseq = tk->clock_was_set_seq;
|
|
*offs_real = tk->offs_real;
|
|
*offs_boot = tk->offs_boot;
|
|
*offs_tai = tk->offs_tai;
|
|
}
|
|
|
|
/* Handle leapsecond insertion adjustments */
|
|
if (unlikely(base.tv64 >= tk->next_leap_ktime.tv64))
|
|
*offs_real = ktime_sub(tk->offs_real, ktime_set(1, 0));
|
|
|
|
} while (read_seqcount_retry(&tk_core.seq, seq));
|
|
|
|
return base;
|
|
}
|
|
|
|
/**
|
|
* do_adjtimex() - Accessor function to NTP __do_adjtimex function
|
|
*/
|
|
int do_adjtimex(struct timex *txc)
|
|
{
|
|
struct timekeeper *tk = &tk_core.timekeeper;
|
|
unsigned long flags;
|
|
struct timespec64 ts;
|
|
s32 orig_tai, tai;
|
|
int ret;
|
|
|
|
/* Validate the data before disabling interrupts */
|
|
ret = ntp_validate_timex(txc);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (txc->modes & ADJ_SETOFFSET) {
|
|
struct timespec delta;
|
|
delta.tv_sec = txc->time.tv_sec;
|
|
delta.tv_nsec = txc->time.tv_usec;
|
|
if (!(txc->modes & ADJ_NANO))
|
|
delta.tv_nsec *= 1000;
|
|
ret = timekeeping_inject_offset(&delta);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
getnstimeofday64(&ts);
|
|
|
|
raw_spin_lock_irqsave(&timekeeper_lock, flags);
|
|
write_seqcount_begin(&tk_core.seq);
|
|
|
|
orig_tai = tai = tk->tai_offset;
|
|
ret = __do_adjtimex(txc, &ts, &tai);
|
|
|
|
if (tai != orig_tai) {
|
|
__timekeeping_set_tai_offset(tk, tai);
|
|
timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET);
|
|
}
|
|
tk_update_leap_state(tk);
|
|
|
|
write_seqcount_end(&tk_core.seq);
|
|
raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
|
|
|
|
if (tai != orig_tai)
|
|
clock_was_set();
|
|
|
|
ntp_notify_cmos_timer();
|
|
|
|
return ret;
|
|
}
|
|
|
|
#ifdef CONFIG_NTP_PPS
|
|
/**
|
|
* hardpps() - Accessor function to NTP __hardpps function
|
|
*/
|
|
void hardpps(const struct timespec64 *phase_ts, const struct timespec64 *raw_ts)
|
|
{
|
|
unsigned long flags;
|
|
|
|
raw_spin_lock_irqsave(&timekeeper_lock, flags);
|
|
write_seqcount_begin(&tk_core.seq);
|
|
|
|
__hardpps(phase_ts, raw_ts);
|
|
|
|
write_seqcount_end(&tk_core.seq);
|
|
raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
|
|
}
|
|
EXPORT_SYMBOL(hardpps);
|
|
#endif
|
|
|
|
/**
|
|
* xtime_update() - advances the timekeeping infrastructure
|
|
* @ticks: number of ticks, that have elapsed since the last call.
|
|
*
|
|
* Must be called with interrupts disabled.
|
|
*/
|
|
void xtime_update(unsigned long ticks)
|
|
{
|
|
write_seqlock(&jiffies_lock);
|
|
do_timer(ticks);
|
|
write_sequnlock(&jiffies_lock);
|
|
update_wall_time();
|
|
}
|