mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-23 00:06:51 +07:00
51f91cbdf5
This adds my clock skew estimation test from the timetest suite. It measures the drift between CLOCK_MONOTONIC and CLOCK_MONOTONIC_RAW and compares it with the current frequency value from adjtimex. It sometimes can trigger false failures when ntpd isn't in a steady state, but its a useful too when doing adjtimex testing. Cc: Shuah Khan <shuahkh@osg.samsung.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Richard Cochran <richardcochran@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Tested-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
155 lines
3.5 KiB
C
155 lines
3.5 KiB
C
/* CLOCK_MONOTONIC vs CLOCK_MONOTONIC_RAW skew test
|
|
* by: john stultz (johnstul@us.ibm.com)
|
|
* John Stultz <john.stultz@linaro.org>
|
|
* (C) Copyright IBM 2012
|
|
* (C) Copyright Linaro Limited 2015
|
|
* Licensed under the GPLv2
|
|
*
|
|
* To build:
|
|
* $ gcc raw_skew.c -o raw_skew -lrt
|
|
*
|
|
* This program is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation, either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <unistd.h>
|
|
#include <stdlib.h>
|
|
#include <sys/time.h>
|
|
#include <sys/timex.h>
|
|
#include <time.h>
|
|
#ifdef KTEST
|
|
#include "../kselftest.h"
|
|
#else
|
|
static inline int ksft_exit_pass(void)
|
|
{
|
|
exit(0);
|
|
}
|
|
static inline int ksft_exit_fail(void)
|
|
{
|
|
exit(1);
|
|
}
|
|
#endif
|
|
|
|
|
|
#define CLOCK_MONOTONIC_RAW 4
|
|
#define NSEC_PER_SEC 1000000000LL
|
|
|
|
#define shift_right(x, s) ({ \
|
|
__typeof__(x) __x = (x); \
|
|
__typeof__(s) __s = (s); \
|
|
__x < 0 ? -(-__x >> __s) : __x >> __s; \
|
|
})
|
|
|
|
long long llabs(long long val)
|
|
{
|
|
if (val < 0)
|
|
val = -val;
|
|
return val;
|
|
}
|
|
|
|
unsigned long long ts_to_nsec(struct timespec ts)
|
|
{
|
|
return ts.tv_sec * NSEC_PER_SEC + ts.tv_nsec;
|
|
}
|
|
|
|
struct timespec nsec_to_ts(long long ns)
|
|
{
|
|
struct timespec ts;
|
|
|
|
ts.tv_sec = ns/NSEC_PER_SEC;
|
|
ts.tv_nsec = ns%NSEC_PER_SEC;
|
|
return ts;
|
|
}
|
|
|
|
long long diff_timespec(struct timespec start, struct timespec end)
|
|
{
|
|
long long start_ns, end_ns;
|
|
|
|
start_ns = ts_to_nsec(start);
|
|
end_ns = ts_to_nsec(end);
|
|
return end_ns - start_ns;
|
|
}
|
|
|
|
void get_monotonic_and_raw(struct timespec *mon, struct timespec *raw)
|
|
{
|
|
struct timespec start, mid, end;
|
|
long long diff = 0, tmp;
|
|
int i;
|
|
|
|
for (i = 0; i < 3; i++) {
|
|
long long newdiff;
|
|
|
|
clock_gettime(CLOCK_MONOTONIC, &start);
|
|
clock_gettime(CLOCK_MONOTONIC_RAW, &mid);
|
|
clock_gettime(CLOCK_MONOTONIC, &end);
|
|
|
|
newdiff = diff_timespec(start, end);
|
|
if (diff == 0 || newdiff < diff) {
|
|
diff = newdiff;
|
|
*raw = mid;
|
|
tmp = (ts_to_nsec(start) + ts_to_nsec(end))/2;
|
|
*mon = nsec_to_ts(tmp);
|
|
}
|
|
}
|
|
}
|
|
|
|
int main(int argv, char **argc)
|
|
{
|
|
struct timespec mon, raw, start, end;
|
|
long long delta1, delta2, interval, eppm, ppm;
|
|
struct timex tx1, tx2;
|
|
|
|
setbuf(stdout, NULL);
|
|
|
|
if (clock_gettime(CLOCK_MONOTONIC_RAW, &raw)) {
|
|
printf("ERR: NO CLOCK_MONOTONIC_RAW\n");
|
|
return -1;
|
|
}
|
|
|
|
tx1.modes = 0;
|
|
adjtimex(&tx1);
|
|
get_monotonic_and_raw(&mon, &raw);
|
|
start = mon;
|
|
delta1 = diff_timespec(mon, raw);
|
|
|
|
if (tx1.offset)
|
|
printf("WARNING: ADJ_OFFSET in progress, this will cause inaccurate results\n");
|
|
|
|
printf("Estimating clock drift: ");
|
|
sleep(120);
|
|
|
|
get_monotonic_and_raw(&mon, &raw);
|
|
end = mon;
|
|
tx2.modes = 0;
|
|
adjtimex(&tx2);
|
|
delta2 = diff_timespec(mon, raw);
|
|
|
|
interval = diff_timespec(start, end);
|
|
|
|
/* calculate measured ppm between MONOTONIC and MONOTONIC_RAW */
|
|
eppm = ((delta2-delta1)*NSEC_PER_SEC)/interval;
|
|
eppm = -eppm;
|
|
printf("%lld.%i(est)", eppm/1000, abs((int)(eppm%1000)));
|
|
|
|
/* Avg the two actual freq samples adjtimex gave us */
|
|
ppm = (tx1.freq + tx2.freq) * 1000 / 2;
|
|
ppm = (long long)tx1.freq * 1000;
|
|
ppm = shift_right(ppm, 16);
|
|
printf(" %lld.%i(act)", ppm/1000, abs((int)(ppm%1000)));
|
|
|
|
if (llabs(eppm - ppm) > 1000) {
|
|
printf(" [FAILED]\n");
|
|
return ksft_exit_fail();
|
|
}
|
|
printf(" [OK]\n");
|
|
return ksft_exit_pass();
|
|
}
|