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// SPDX-License-Identifier: GPL-2.0
#define _GNU_SOURCE
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include <fcntl.h>
#include <sched.h>
#include <time.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/syscall.h>
#include <dlfcn.h>
#include "log.h"
#include "timens.h"
typedef int (*vgettime_t)(clockid_t, struct timespec *);
vgettime_t vdso_clock_gettime;
static void fill_function_pointers(void)
{
void *vdso = dlopen("linux-vdso.so.1",
RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
if (!vdso)
vdso = dlopen("linux-gate.so.1",
RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
if (!vdso)
vdso = dlopen("linux-vdso32.so.1",
RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
if (!vdso)
vdso = dlopen("linux-vdso64.so.1",
RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
if (!vdso) {
pr_err("[WARN]\tfailed to find vDSO\n");
return;
}
vdso_clock_gettime = (vgettime_t)dlsym(vdso, "__vdso_clock_gettime");
if (!vdso_clock_gettime)
vdso_clock_gettime = (vgettime_t)dlsym(vdso, "__kernel_clock_gettime");
if (!vdso_clock_gettime)
pr_err("Warning: failed to find clock_gettime in vDSO\n");
}
static void test(clock_t clockid, char *clockstr, bool in_ns)
{
struct timespec tp, start;
long i = 0;
const int timeout = 3;
vdso_clock_gettime(clockid, &start);
tp = start;
for (tp = start; start.tv_sec + timeout > tp.tv_sec ||
(start.tv_sec + timeout == tp.tv_sec &&
start.tv_nsec > tp.tv_nsec); i++) {
vdso_clock_gettime(clockid, &tp);
}
ksft_test_result_pass("%s:\tclock: %10s\tcycles:\t%10ld\n",
in_ns ? "ns" : "host", clockstr, i);
}
int main(int argc, char *argv[])
{
time_t offset = 10;
int nsfd;
ksft_set_plan(8);
fill_function_pointers();
test(CLOCK_MONOTONIC, "monotonic", false);
test(CLOCK_MONOTONIC_COARSE, "monotonic-coarse", false);
test(CLOCK_MONOTONIC_RAW, "monotonic-raw", false);
test(CLOCK_BOOTTIME, "boottime", false);
nscheck();
if (unshare_timens())
return 1;
nsfd = open("/proc/self/ns/time_for_children", O_RDONLY);
if (nsfd < 0)
return pr_perror("Can't open a time namespace");
if (_settime(CLOCK_MONOTONIC, offset))
return 1;
if (_settime(CLOCK_BOOTTIME, offset))
return 1;
if (setns(nsfd, CLONE_NEWTIME))
return pr_perror("setns");
test(CLOCK_MONOTONIC, "monotonic", true);
test(CLOCK_MONOTONIC_COARSE, "monotonic-coarse", true);
test(CLOCK_MONOTONIC_RAW, "monotonic-raw", true);
test(CLOCK_BOOTTIME, "boottime", true);
ksft_exit_pass();
return 0;
}
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