[LTP] [PATCH v3 2/2] syscalls/clock_adjtime: create clock_adjtime syscall tests
Cyril Hrubis
chrubis@suse.cz
Wed Mar 13 17:32:39 CET 2019
Hi!
I finally had time to read the manual page for adjtime and look into
these tests. They look more or less fine, the only problem here is that
we merely scratch the surface here, i.e. most of the STA_* constants are
not tested etc. I guess that with CLOCK_MONOTONIC_RAW we should be even
able measure that the time has been adjusted, leap second inserted, etc.
However such tests would require quite a lot of effort. Even triggering
leap second insertion/deletion requires fiddling with system time and
sleeping till the kernel state machine does it job.
> diff --git a/testcases/kernel/syscalls/clock_adjtime/clock_adjtime01.c b/testcases/kernel/syscalls/clock_adjtime/clock_adjtime01.c
> new file mode 100644
> index 000000000..999865b96
> --- /dev/null
> +++ b/testcases/kernel/syscalls/clock_adjtime/clock_adjtime01.c
> @@ -0,0 +1,249 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (c) 2019 Linaro Limited. All rights reserved.
> + * Author: Rafael David Tinoco <rafael.tinoco@linaro.org>
> + */
> +
> +/*
> + * clock_adjtime() syscall might have as execution path:
> + *
> + * 1) a regular POSIX clock (only REALTIME clock implements adjtime())
> + * - will behave exactly like adjtimex() system call.
> + * - only one being tested here.
> + *
> + * 2) a dynamic POSIX clock (which ops are implemented by PTP clocks)
> + * - will trigger the PTP clock driver function "adjtime()"
> + * - different implementations from one PTP clock to another
> + * - might return EOPNOTSUPP (like ptp_kvm_caps, for example)
> + * - no entry point for clock_adjtime(), missing "CLOCK_PTP" model
> + *
> + * so it is sane to check possible adjustments:
> + *
> + * - ADJ_OFFSET - usec or nsec, kernel adjusts time gradually by offset
> + * (-512000 < offset < 512000)
> + * - ADJ_FREQUENCY - system clock frequency offset
> + * - ADJ_MAXERROR - maximum error (usec)
> + * - ADJ_ESTERROR - estimated time error in us
> + * - ADJ_STATUS - clock command/status of ntp implementation
> + * - ADJ_TIMECONST - PLL stiffness (jitter dependent) + poll int for PLL
> + * - ADJ_TICK - us between clock ticks
> + * (>= 900000/HZ, <= 1100000/HZ)
> + *
> + * and also the standalone ones (using .offset variable):
> + *
> + * - ADJ_OFFSET_SINGLESHOT - behave like adjtime()
> + * - ADJ_OFFSET_SS_READ - ret remaining time for completion after SINGLESHOT
> + *
> + * For ADJ_STATUS, consider the following flags:
> + *
> + * rw STA_PLL - enable phase-locked loop updates (ADJ_OFFSET)
> + * rw STA_PPSFREQ - enable PPS (pulse-per-second) freq discipline
> + * rw STA_PPSTIME - enable PPS time discipline
> + * rw STA_FLL - select freq-locked loop mode.
> + * rw STA_INS - ins leap sec after the last sec of UTC day (all days)
> + * rw STA_DEL - del leap sec at last sec of UTC day (all days)
> + * rw STA_UNSYNC - clock unsynced
> + * rw STA_FREQHOLD - hold freq. ADJ_OFFSET made w/out auto small adjs
> + * ro STA_PPSSIGNAL - valid PPS (pulse-per-second) signal is present
> + * ro STA_PPSJITTER - PPS signal jitter exceeded.
> + * ro STA_PPSWANDER - PPS signal wander exceeded.
> + * ro STA_PPSERROR - PPS signal calibration error.
> + * ro STA_CLOKERR - clock HW fault.
> + * ro STA_NANO - 0 = us, 1 = ns (set = ADJ_NANO, cl = ADJ_MICRO)
> + * rw STA_MODE - mode: 0 = phased locked loop. 1 = freq locked loop
> + * ro STA_CLK - clock source. unused.
> + */
> +
> +#include "config.h"
> +#include "tst_test.h"
> +#include "lapi/syscalls.h"
> +#include "lapi/posix_clocks.h"
> +#include "tst_timer.h"
> +#include "tst_safe_clocks.h"
> +#include <sys/timex.h>
> +
> +static long hz;
> +static struct timex saved, ttxc;
> +
> +#define ADJ_ALL (ADJ_OFFSET | ADJ_FREQUENCY | ADJ_MAXERROR | ADJ_ESTERROR | \
> + ADJ_STATUS | ADJ_TIMECONST | ADJ_TICK)
> +
> +struct test_case {
> + unsigned int modes;
> + long highlimit;
> + long *ptr;
> + long delta;
> +};
> +
> +struct test_case tc[] = {
> + {
> + .modes = ADJ_OFFSET_SINGLESHOT,
> + },
> + {
> + .modes = ADJ_OFFSET_SS_READ,
> + },
> + {
> + .modes = ADJ_ALL,
> + },
> + {
> + .modes = ADJ_OFFSET,
> + .highlimit = 512000,
> + .ptr = &ttxc.offset,
> + .delta = 10000,
> + },
I wonder what we should do with STA_NANO vs STA_MICRO if a ntp daemon
set STA_NANO this limit would be three orders of magnitude off, maybe we
should check for this in the setup as well.
Also manual states that the limit is -0.5, +0.5 range, we should really
set the limit to 500000 then, then we can just clamp the value instead
of decreasing by 2 * delta (why do we do even do that) donw in the test
function.
> + {
> + .modes = ADJ_FREQUENCY,
> + .ptr = &ttxc.freq,
> + .delta = 100,
> + },
> + {
> + .modes = ADJ_MAXERROR,
> + .ptr = &ttxc.maxerror,
> + .delta = 100,
> + },
> + {
> + .modes = ADJ_ESTERROR,
> + .ptr = &ttxc.esterror,
> + .delta = 100,
> + },
> + {
> + .modes = ADJ_TIMECONST,
> + .ptr = &ttxc.constant,
> + .delta = 1,
> + },
> + {
> + .modes = ADJ_TICK,
> + .highlimit = 1100000,
> + .ptr = &ttxc.tick,
> + .delta = 1000,
> + },
> +};
> +
> +/*
> + * bad pointer w/ libc causes SIGSEGV signal, call syscall directly
> + */
> +static int sys_clock_adjtime(clockid_t clk_id, struct timex *txc)
> +{
> + return tst_syscall(__NR_clock_adjtime, clk_id, txc);
> +}
> +
> +static void timex_show(char *given, struct timex txc)
> +{
> + tst_res(TINFO, "%s\n"
> + " mode: %d\n"
> + " offset: %ld\n"
> + " frequency: %ld\n"
> + " maxerror: %ld\n"
> + " esterror: %ld\n"
> + " status: %d (0x%x)\n"
> + " time_constant: %ld\n"
> + " precision: %ld\n"
> + " tolerance: %ld\n"
> + " tick: %ld\n"
> + " raw time: %d(s) %d(us)",
> + given,
> + txc.modes,
> + txc.offset,
> + txc.freq,
> + txc.maxerror,
> + txc.esterror,
> + txc.status,
> + txc.status,
> + txc.constant,
> + txc.precision,
> + txc.tolerance,
> + txc.tick,
> + (int)txc.time.tv_sec,
> + (int)txc.time.tv_usec);
> +}
> +
> +static void verify_clock_adjtime(unsigned int i)
> +{
> + long ptroff, *ptr = NULL;
> + struct timex verify;
> +
> + memset(&ttxc, 0, sizeof(struct timex));
> + memset(&verify, 0, sizeof(struct timex));
> +
> + SAFE_CLOCK_ADJTIME(CLOCK_REALTIME, &ttxc);
> + timex_show("GET", ttxc);
> +
> + ttxc.modes = tc[i].modes;
> +
> + if (tc[i].ptr && tc[i].delta) {
> +
> + *tc[i].ptr += tc[i].delta;
> +
> + /* fix limits, if existent, so no errors occur */
> +
> + if (tc[i].highlimit) {
> + if (*tc[i].ptr >= tc[i].highlimit)
> + *tc[i].ptr -= (2 * tc[i].delta);
> + }
Here if we had the highlimit correct we can just do:
if (tc[i].highlimit) {
if (*tc[i].ptr > tc[i].highlimit)
*tc[i].ptr = tc[i].highlimit;
}
Or is there a reason why this cannot work?
> + }
> +
> + SAFE_CLOCK_ADJTIME(CLOCK_REALTIME, &ttxc);
> + timex_show("SET", ttxc);
> +
> + if (tc[i].ptr) {
> +
> + /* adjtimex field being tested so we can verify later */
> +
> + ptroff = (long) tc[i].ptr - (long) &ttxc;
> + ptr = (void *) &verify + ptroff;
> + }
> +
> + TEST(sys_clock_adjtime(CLOCK_REALTIME, &verify));
> + timex_show("VERIFY", verify);
> +
> + if (tc[i].ptr && *tc[i].ptr != *ptr) {
> +
> + tst_res(TFAIL, "clock_adjtime(): could not set value (mode=%x)",
> + tc[i].modes);
> + }
> +
> + if (TST_RET < 0) {
> + tst_res(TFAIL | TTERRNO, "clock_adjtime(): mode=%x, returned "
> + "error", tc[i].modes);
> + }
> +
> + tst_res(TPASS, "clock_adjtime(): success (mode=%x)", tc[i].modes);
> +}
> +
> +static void setup(void)
> +{
> + size_t i;
> +
> + hz = SAFE_SYSCONF(_SC_CLK_TCK);
> +
> + /* fix high and low limits by dividing it per HZ value */
> + for (i = 0; i < ARRAY_SIZE(tc); i++) {
> + if (tc[i].modes == ADJ_TICK)
> + tc[i].highlimit /= hz;
> + }
> +
> + SAFE_CLOCK_ADJTIME(CLOCK_REALTIME, &saved);
> +}
> +
> +static void cleanup(void)
> +{
> + saved.modes = ADJ_ALL;
> +
> + /* restore clock resolution based on original status flag */
> +
> + if (saved.status & STA_NANO)
> + saved.modes |= ADJ_NANO;
> + else
> + saved.modes |= ADJ_MICRO;
> +
> + /* restore original clock flags */
> +
> + SAFE_CLOCK_ADJTIME(CLOCK_REALTIME, &saved);
> +}
> +
> +static struct tst_test test = {
> + .test = verify_clock_adjtime,
> + .setup = setup,
> + .cleanup = cleanup,
> + .tcnt = ARRAY_SIZE(tc),
> + .needs_root = 1,
I wonder if we should set .restore_wallclock here, is the wallclock
significantly distorted by fiddling with adjtimex.
> +};
> diff --git a/testcases/kernel/syscalls/clock_adjtime/clock_adjtime02.c b/testcases/kernel/syscalls/clock_adjtime/clock_adjtime02.c
> new file mode 100644
> index 000000000..05b4b0a18
> --- /dev/null
> +++ b/testcases/kernel/syscalls/clock_adjtime/clock_adjtime02.c
> @@ -0,0 +1,261 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (c) 2019 Linaro Limited. All rights reserved.
> + * Author: Rafael David Tinoco <rafael.tinoco@linaro.org>
> + */
> +
> +/*
> + * clock_adjtime() syscall might have as execution path:
> + *
> + * 1) a regular POSIX clock (only REALTIME clock implements adjtime())
> + * - will behave exactly like adjtimex() system call.
> + * - only one being tested here.
> + *
> + * 2) a dynamic POSIX clock (which ops are implemented by PTP clocks)
> + * - will trigger the PTP clock driver function "adjtime()"
> + * - different implementations from one PTP clock to another
> + * - might return EOPNOTSUPP (like ptp_kvm_caps, for example)
> + * - no entry point for clock_adjtime(), missing "CLOCK_PTP" model
> + *
> + * so it is sane to check for the following errors:
> + *
> + * EINVAL - clock id being used does not exist
> + *
> + * EFAULT - (struct timex *) does not point to valid memory
> + *
> + * EINVAL - ADJ_OFFSET + .offset outside range -512000 < x < 512000
> + * (after 2.6.26, kernels normalize to the limit if outside range)
> + *
> + * EINVAL - ADJ_FREQUENCY + .freq outside range -32768000 < x < 3276800
> + * (after 2.6.26, kernels normalize to the limit if outside range)
> + *
> + * EINVAL - .tick outside permitted range (900000/HZ < .tick < 1100000/HZ)
> + *
> + * EPERM - .modes is neither 0 nor ADJ_OFFSET_SS_READ (CAP_SYS_TIME required)
> + *
> + * EINVAL - .status other than those listed bellow
> + *
> + * For ADJ_STATUS, consider the following flags:
> + *
> + * rw STA_PLL - enable phase-locked loop updates (ADJ_OFFSET)
> + * rw STA_PPSFREQ - enable PPS (pulse-per-second) freq discipline
> + * rw STA_PPSTIME - enable PPS time discipline
> + * rw STA_FLL - select freq-locked loop mode.
> + * rw STA_INS - ins leap sec after the last sec of UTC day (all days)
> + * rw STA_DEL - del leap sec at last sec of UTC day (all days)
> + * rw STA_UNSYNC - clock unsynced
> + * rw STA_FREQHOLD - hold freq. ADJ_OFFSET made w/out auto small adjs
> + * ro STA_PPSSIGNAL - valid PPS (pulse-per-second) signal is present
> + * ro STA_PPSJITTER - PPS signal jitter exceeded.
> + * ro STA_PPSWANDER - PPS signal wander exceeded.
> + * ro STA_PPSERROR - PPS signal calibration error.
> + * ro STA_CLOKERR - clock HW fault.
> + * ro STA_NANO - 0 = us, 1 = ns (set = ADJ_NANO, cl = ADJ_MICRO)
> + * rw STA_MODE - mode: 0 = phased locked loop. 1 = freq locked loop
> + * ro STA_CLK - clock source. unused.
> + */
> +
> +#include "config.h"
> +#include "tst_test.h"
> +#include "lapi/syscalls.h"
> +#include "lapi/posix_clocks.h"
> +#include "tst_timer.h"
> +#include "tst_safe_clocks.h"
> +#include <sys/timex.h>
> +#include <pwd.h>
> +
> +#include <stdio.h>
> +
> +static long hz;
> +static struct timex saved, ttxc;
> +
> +#define ADJ_ALL (ADJ_OFFSET | ADJ_FREQUENCY | ADJ_MAXERROR | ADJ_ESTERROR | \
> + ADJ_STATUS | ADJ_TIMECONST | ADJ_TICK)
> +
> +#define MAX_CLOCKS 16
Can we put this into include/lapi/posix_clocks.h and use that in all
clock testcases?
Otherwise we will end up adjusting five different places once kernel
devs happen to add a few more clocks.
> +struct test_case {
> + clockid_t clktype;
> + unsigned int modes;
> + long lowlimit;
> + long highlimit;
> + long *ptr;
> + long delta;
> + int exp_err;
> + int droproot;
> +};
> +
> +struct test_case tc[] = {
> + {
> + .clktype = MAX_CLOCKS,
> + .exp_err = EINVAL,
> + },
> + {
> + .clktype = MAX_CLOCKS + 1,
> + .exp_err = EINVAL,
> + },
> + {
> + .clktype = CLOCK_REALTIME,
> + .modes = ADJ_ALL,
> + .exp_err = EFAULT,
> + },
> + {
> + .clktype = CLOCK_REALTIME,
> + .modes = ADJ_TICK,
> + .lowlimit = 900000,
> + .ptr = &ttxc.tick,
> + .delta = 1,
> + .exp_err = EINVAL,
> + },
> + {
> + .clktype = CLOCK_REALTIME,
> + .modes = ADJ_TICK,
> + .highlimit = 1100000,
> + .ptr = &ttxc.tick,
> + .delta = 1,
> + .exp_err = EINVAL,
> + },
> + {
> + .clktype = CLOCK_REALTIME,
> + .modes = ADJ_ALL,
> + .exp_err = EPERM,
> + .droproot = 1,
> + },
> +};
> +
> +/*
> + * bad pointer w/ libc causes SIGSEGV signal, call syscall directly
> + */
> +static int sys_clock_adjtime(clockid_t clk_id, struct timex *txc)
> +{
> + return tst_syscall(__NR_clock_adjtime, clk_id, txc);
> +}
> +
> +static void timex_show(char *given, struct timex txc)
> +{
> + tst_res(TINFO, "%s\n"
> + " mode: 0x%x\n"
> + " offset: %ld\n"
> + " frequency: %ld\n"
> + " maxerror: %ld\n"
> + " esterror: %ld\n"
> + " status: 0x%x\n"
> + " time_constant: %ld\n"
> + " precision: %ld\n"
> + " tolerance: %ld\n"
> + " tick: %ld\n"
> + " raw time: %d(s) %d(us)",
> + given,
> + txc.modes,
> + txc.offset,
> + txc.freq,
> + txc.maxerror,
> + txc.esterror,
> + txc.status,
> + txc.constant,
> + txc.precision,
> + txc.tolerance,
> + txc.tick,
> + (int)txc.time.tv_sec,
> + (int)txc.time.tv_usec);
> +}
You should really put this into a header in the clock_adjtime directory
and include it in both test.
> +static void verify_clock_adjtime(unsigned int i)
> +{
> + uid_t whoami = 0;
> + struct timex *txcptr;
> + struct passwd *nobody;
> + static const char name[] = "nobody";
> +
> + txcptr = &ttxc;
> +
> + memset(txcptr, 0, sizeof(struct timex));
> +
> + SAFE_CLOCK_ADJTIME(CLOCK_REALTIME, txcptr);
> + timex_show("GET", *txcptr);
> +
> + if (tc[i].droproot) {
> + nobody = SAFE_GETPWNAM(name);
> + whoami = nobody->pw_uid;
> + SAFE_SETEUID(whoami);
> + }
> +
> + txcptr->modes = tc[i].modes;
> +
> + if (tc[i].ptr) {
> +
> + if (tc[i].lowlimit)
> + *tc[i].ptr = tc[i].lowlimit - tc[i].delta;
> +
> + if (tc[i].highlimit)
> + *tc[i].ptr = tc[i].highlimit + tc[i].delta;
> + }
> +
> + /* special case - if txcptr != NULL, SIGSEGV is throwed */
> + if (tc[i].exp_err == EFAULT)
> + txcptr = NULL;
Please use tst_get_bad_addr()
> + TEST(sys_clock_adjtime(tc[i].clktype, txcptr));
> + if (txcptr)
> + timex_show("TEST", *txcptr);
> +
> + if (TST_RET >= 0) {
> + tst_res(TFAIL, "clock_adjtime(): passed unexpectedly (mode=%x, "
> + "uid=%d)", tc[i].modes, whoami);
> + return;
> + }
> +
> + if (tc[i].exp_err != TST_ERR) {
> + tst_res(TFAIL | TTERRNO, "clock_adjtime(): expected %d but "
> + "failed with %d (mode=%x, uid=%d)",
> + tc[i].exp_err, TST_ERR, tc[i].modes, whoami);
> + return;
> + }
> +
> + tst_res(TPASS, "clock_adjtime(): failed as expected (mode=0x%x, "
> + "uid=%d)", tc[i].modes, whoami);
> +
> + if (tc[i].droproot)
> + SAFE_SETEUID(0);
> +}
> +
> +static void setup(void)
> +{
> + size_t i;
> +
> + hz = SAFE_SYSCONF(_SC_CLK_TCK);
> +
> + /* fix high and low limits by dividing it per HZ value */
> + for (i = 0; i < ARRAY_SIZE(tc); i++) {
> + if (tc[i].modes == ADJ_TICK) {
> + tc[i].highlimit /= hz;
> + tc[i].lowlimit /= hz;
> + }
> + }
> +
> + SAFE_CLOCK_ADJTIME(CLOCK_REALTIME, &saved);
> +}
> +
> +static void cleanup(void)
> +{
> + saved.modes = ADJ_ALL;
> +
> + /* restore clock resolution based on original status flag */
> +
> + if (saved.status & STA_NANO)
> + saved.modes |= ADJ_NANO;
> + else
> + saved.modes |= ADJ_MICRO;
> +
> + /* restore original clock flags */
> +
> + SAFE_CLOCK_ADJTIME(CLOCK_REALTIME, &saved);
> +}
> +
> +static struct tst_test test = {
> + .test = verify_clock_adjtime,
> + .setup = setup,
> + .cleanup = cleanup,
> + .tcnt = ARRAY_SIZE(tc),
> + .needs_root = 1,
> +};
> --
> 2.20.1
>
>
> --
> Mailing list info: https://lists.linux.it/listinfo/ltp
--
Cyril Hrubis
chrubis@suse.cz
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