Files
cubelinux-kernel/tools/testing/selftests/proc/proc-uptime-001.c
T
Greg Kroah-Hartman 598cf27219 Linux 6.19.3
Link: https://lore.kernel.org/r/20260217200002.683975158@linuxfoundation.org
Tested-by: Florian Fainelli <florian.fainelli@broadcom.com>
Tested-by: Takeshi Ogasawara <takeshi.ogasawara@futuring-girl.com>
Tested-by: Peter Schneider <pschneider1968@googlemail.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Salvatore Bonaccorso <carnil@debian.org>
Tested-by: Brett A C Sheffield <bacs@librecast.net>
Tested-by: Mark Brown <broonie@kernel.org>
Tested-by: Luna Jernberg <droidbittin@gmail.com>
Tested-by: Ronald Warsow <rwarsow@gmx.de>
Tested-by: Justin M. Forbes <jforbes@fedoraproject.org>
Tested-by: Ron Economos <re@w6rz.net>
Tested-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-02-19 16:33:27 +01:00

59 lines
1.6 KiB
C

/*
* Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
// Test that boottime value in /proc/uptime and CLOCK_BOOTTIME increment
// monotonically. We don't test idle time monotonicity due to broken iowait
// task counting, cf: comment above get_cpu_idle_time_us()
#undef NDEBUG
#include <assert.h>
#include <stdint.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include "proc-uptime.h"
int main(void)
{
uint64_t start, u0, u1, c0, c1;
int fd;
fd = open("/proc/uptime", O_RDONLY);
assert(fd >= 0);
u0 = proc_uptime(fd);
start = u0;
c0 = clock_boottime();
do {
u1 = proc_uptime(fd);
c1 = clock_boottime();
/* Is /proc/uptime monotonic ? */
assert(u1 >= u0);
/* Is CLOCK_BOOTTIME monotonic ? */
assert(c1 >= c0);
/* Is CLOCK_BOOTTIME VS /proc/uptime monotonic ? */
assert(c0 >= u0);
u0 = u1;
c0 = c1;
} while (u1 - start < 100);
return 0;
}