tjh.dev
+5
include/linux/timekeeper_internal.h
+5
include/linux/timekeeper_internal.h
···
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* @cs_was_changed_seq: The sequence number of clocksource change events
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* @next_leap_ktime: CLOCK_MONOTONIC time value of a pending leap-second
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* @raw_sec: CLOCK_MONOTONIC_RAW time in seconds
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* @monotonic_to_boot: CLOCK_MONOTONIC to CLOCK_BOOTTIME offset
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* @cycle_interval: Number of clock cycles in one NTP interval
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* @xtime_interval: Number of clock shifted nano seconds in one NTP
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* interval.
···
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*
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* wall_to_monotonic is no longer the boot time, getboottime must be
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* used instead.
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*
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* @monotonic_to_boottime is a timespec64 representation of @offs_boot to
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* accelerate the VDSO update for CLOCK_BOOTTIME.
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*/
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struct timekeeper {
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struct tk_read_base tkr_mono;
···
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u8 cs_was_changed_seq;
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ktime_t next_leap_ktime;
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u64 raw_sec;
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struct timespec64 monotonic_to_boot;
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/* The following members are for timekeeping internal use */
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u64 cycle_interval;
+5
kernel/time/timekeeping.c
+5
kernel/time/timekeeping.c
···
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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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* Timespec representation for VDSO update to avoid 64bit division
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* on every update.
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*/
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tk->monotonic_to_boot = ktime_to_timespec64(tk->offs_boot);
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}
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/*
+13
-9
kernel/time/vsyscall.c
+13
-9
kernel/time/vsyscall.c
···
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struct timekeeper *tk)
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{
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struct vdso_timestamp *vdso_ts;
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u64 nsec;
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u64 nsec, sec;
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vdata[CS_HRES_COARSE].cycle_last = tk->tkr_mono.cycle_last;
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vdata[CS_HRES_COARSE].mask = tk->tkr_mono.mask;
···
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}
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vdso_ts->nsec = nsec;
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-
/* CLOCK_MONOTONIC_RAW */
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vdso_ts = &vdata[CS_RAW].basetime[CLOCK_MONOTONIC_RAW];
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vdso_ts->sec = tk->raw_sec;
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vdso_ts->nsec = tk->tkr_raw.xtime_nsec;
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/* Copy MONOTONIC time for BOOTTIME */
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sec = vdso_ts->sec;
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/* Add the boot offset */
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sec += tk->monotonic_to_boot.tv_sec;
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nsec += (u64)tk->monotonic_to_boot.tv_nsec << tk->tkr_mono.shift;
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/* CLOCK_BOOTTIME */
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vdso_ts = &vdata[CS_HRES_COARSE].basetime[CLOCK_BOOTTIME];
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-
vdso_ts->sec = tk->xtime_sec + tk->wall_to_monotonic.tv_sec;
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nsec = tk->tkr_mono.xtime_nsec;
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nsec += ((u64)(tk->wall_to_monotonic.tv_nsec +
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ktime_to_ns(tk->offs_boot)) << tk->tkr_mono.shift);
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vdso_ts->sec = sec;
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+
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while (nsec >= (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift)) {
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nsec -= (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift);
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vdso_ts->sec++;
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}
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vdso_ts->nsec = nsec;
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/* CLOCK_MONOTONIC_RAW */
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vdso_ts = &vdata[CS_RAW].basetime[CLOCK_MONOTONIC_RAW];
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vdso_ts->sec = tk->raw_sec;
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vdso_ts->nsec = tk->tkr_raw.xtime_nsec;
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/* CLOCK_TAI */
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vdso_ts = &vdata[CS_HRES_COARSE].basetime[CLOCK_TAI];