128 lines
3.7 KiB
C
128 lines
3.7 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Copyright 2019 ARM Ltd.
|
|
*
|
|
* Generic implementation of update_vsyscall and update_vsyscall_tz.
|
|
*
|
|
* Based on the x86 specific implementation.
|
|
*/
|
|
|
|
#include <linux/hrtimer.h>
|
|
#include <linux/timekeeper_internal.h>
|
|
#include <vdso/datapage.h>
|
|
#include <vdso/helpers.h>
|
|
#include <vdso/vsyscall.h>
|
|
|
|
static inline void update_vdso_data(struct vdso_data *vdata,
|
|
struct timekeeper *tk)
|
|
{
|
|
struct vdso_timestamp *vdso_ts;
|
|
u64 nsec, sec;
|
|
|
|
vdata[CS_HRES_COARSE].cycle_last = tk->tkr_mono.cycle_last;
|
|
vdata[CS_HRES_COARSE].mask = tk->tkr_mono.mask;
|
|
vdata[CS_HRES_COARSE].mult = tk->tkr_mono.mult;
|
|
vdata[CS_HRES_COARSE].shift = tk->tkr_mono.shift;
|
|
vdata[CS_RAW].cycle_last = tk->tkr_raw.cycle_last;
|
|
vdata[CS_RAW].mask = tk->tkr_raw.mask;
|
|
vdata[CS_RAW].mult = tk->tkr_raw.mult;
|
|
vdata[CS_RAW].shift = tk->tkr_raw.shift;
|
|
|
|
/* CLOCK_MONOTONIC */
|
|
vdso_ts = &vdata[CS_HRES_COARSE].basetime[CLOCK_MONOTONIC];
|
|
vdso_ts->sec = tk->xtime_sec + tk->wall_to_monotonic.tv_sec;
|
|
|
|
nsec = tk->tkr_mono.xtime_nsec;
|
|
nsec += ((u64)tk->wall_to_monotonic.tv_nsec << tk->tkr_mono.shift);
|
|
while (nsec >= (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift)) {
|
|
nsec -= (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift);
|
|
vdso_ts->sec++;
|
|
}
|
|
vdso_ts->nsec = nsec;
|
|
|
|
/* Copy MONOTONIC time for BOOTTIME */
|
|
sec = vdso_ts->sec;
|
|
/* Add the boot offset */
|
|
sec += tk->monotonic_to_boot.tv_sec;
|
|
nsec += (u64)tk->monotonic_to_boot.tv_nsec << tk->tkr_mono.shift;
|
|
|
|
/* CLOCK_BOOTTIME */
|
|
vdso_ts = &vdata[CS_HRES_COARSE].basetime[CLOCK_BOOTTIME];
|
|
vdso_ts->sec = sec;
|
|
|
|
while (nsec >= (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift)) {
|
|
nsec -= (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift);
|
|
vdso_ts->sec++;
|
|
}
|
|
vdso_ts->nsec = nsec;
|
|
|
|
/* CLOCK_MONOTONIC_RAW */
|
|
vdso_ts = &vdata[CS_RAW].basetime[CLOCK_MONOTONIC_RAW];
|
|
vdso_ts->sec = tk->raw_sec;
|
|
vdso_ts->nsec = tk->tkr_raw.xtime_nsec;
|
|
|
|
/* CLOCK_TAI */
|
|
vdso_ts = &vdata[CS_HRES_COARSE].basetime[CLOCK_TAI];
|
|
vdso_ts->sec = tk->xtime_sec + (s64)tk->tai_offset;
|
|
vdso_ts->nsec = tk->tkr_mono.xtime_nsec;
|
|
}
|
|
|
|
void update_vsyscall(struct timekeeper *tk)
|
|
{
|
|
struct vdso_data *vdata = __arch_get_k_vdso_data();
|
|
struct vdso_timestamp *vdso_ts;
|
|
u64 nsec;
|
|
|
|
/* copy vsyscall data */
|
|
vdso_write_begin(vdata);
|
|
|
|
vdata[CS_HRES_COARSE].clock_mode = __arch_get_clock_mode(tk);
|
|
vdata[CS_RAW].clock_mode = __arch_get_clock_mode(tk);
|
|
|
|
/* CLOCK_REALTIME also required for time() */
|
|
vdso_ts = &vdata[CS_HRES_COARSE].basetime[CLOCK_REALTIME];
|
|
vdso_ts->sec = tk->xtime_sec;
|
|
vdso_ts->nsec = tk->tkr_mono.xtime_nsec;
|
|
|
|
/* CLOCK_REALTIME_COARSE */
|
|
vdso_ts = &vdata[CS_HRES_COARSE].basetime[CLOCK_REALTIME_COARSE];
|
|
vdso_ts->sec = tk->xtime_sec;
|
|
vdso_ts->nsec = tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift;
|
|
|
|
/* CLOCK_MONOTONIC_COARSE */
|
|
vdso_ts = &vdata[CS_HRES_COARSE].basetime[CLOCK_MONOTONIC_COARSE];
|
|
vdso_ts->sec = tk->xtime_sec + tk->wall_to_monotonic.tv_sec;
|
|
nsec = tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift;
|
|
nsec = nsec + tk->wall_to_monotonic.tv_nsec;
|
|
vdso_ts->sec += __iter_div_u64_rem(nsec, NSEC_PER_SEC, &vdso_ts->nsec);
|
|
|
|
/*
|
|
* Read without the seqlock held by clock_getres().
|
|
* Note: No need to have a second copy.
|
|
*/
|
|
WRITE_ONCE(vdata[CS_HRES_COARSE].hrtimer_res, hrtimer_resolution);
|
|
|
|
/*
|
|
* Architectures can opt out of updating the high resolution part
|
|
* of the VDSO.
|
|
*/
|
|
if (__arch_update_vdso_data())
|
|
update_vdso_data(vdata, tk);
|
|
|
|
__arch_update_vsyscall(vdata, tk);
|
|
|
|
vdso_write_end(vdata);
|
|
|
|
__arch_sync_vdso_data(vdata);
|
|
}
|
|
|
|
void update_vsyscall_tz(void)
|
|
{
|
|
struct vdso_data *vdata = __arch_get_k_vdso_data();
|
|
|
|
vdata[CS_HRES_COARSE].tz_minuteswest = sys_tz.tz_minuteswest;
|
|
vdata[CS_HRES_COARSE].tz_dsttime = sys_tz.tz_dsttime;
|
|
|
|
__arch_sync_vdso_data(vdata);
|
|
}
|