glibc/support/timespec.c
Lucas A. M. Magalhaes 04deeaa9ea Fix time/tst-cpuclock1 intermitent failures
This test fails intermittently in systems with heavy load as
CLOCK_PROCESS_CPUTIME_ID is subject to scheduler pressure.  Thus the
test boundaries were relaxed to keep it from failing on such systems.

A refactor of the spent time checking was made with some support
functions.  With the advantage to representing time jitter in percent
of the target.

The values used by the test boundaries are all empirical.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2020-07-10 19:41:06 -03:00

124 lines
4.1 KiB
C

/* Support code for timespec checks.
Copyright (C) 2019-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <support/timespec.h>
#include <stdio.h>
#include <stdint.h>
#include <assert.h>
#include <intprops.h>
void
test_timespec_before_impl (const char *file, int line,
const struct timespec left,
const struct timespec right)
{
if (left.tv_sec > right.tv_sec
|| (left.tv_sec == right.tv_sec
&& left.tv_nsec > right.tv_nsec)) {
support_record_failure ();
const struct timespec diff = timespec_sub (left, right);
printf ("%s:%d: %jd.%09jds not before %jd.%09jds "
"(difference %jd.%09jds)\n",
file, line,
(intmax_t) left.tv_sec, (intmax_t) left.tv_nsec,
(intmax_t) right.tv_sec, (intmax_t) right.tv_nsec,
(intmax_t) diff.tv_sec, (intmax_t) diff.tv_nsec);
}
}
void
test_timespec_equal_or_after_impl (const char *file, int line,
const struct timespec left,
const struct timespec right)
{
if (left.tv_sec < right.tv_sec
|| (left.tv_sec == right.tv_sec
&& left.tv_nsec < right.tv_nsec)) {
support_record_failure ();
const struct timespec diff = timespec_sub (right, left);
printf ("%s:%d: %jd.%09jds not after %jd.%09jds "
"(difference %jd.%09jds)\n",
file, line,
(intmax_t) left.tv_sec, (intmax_t) left.tv_nsec,
(intmax_t) right.tv_sec, (intmax_t) right.tv_nsec,
(intmax_t) diff.tv_sec, (intmax_t) diff.tv_nsec);
}
}
/* Convert TIME to nanoseconds stored in a long.
Returns long maximum or minimum if the conversion overflows
or underflows, respectively. */
long
support_timespec_ns (struct timespec time)
{
long time_ns;
if (INT_MULTIPLY_WRAPV(time.tv_sec, TIMESPEC_HZ, &time_ns))
{
return (time.tv_sec < 0) ? TYPE_MINIMUM(long): TYPE_MAXIMUM(long);
}
if (INT_ADD_WRAPV(time_ns, time.tv_nsec, &time_ns))
{
return (time.tv_nsec < 0) ? TYPE_MINIMUM(long): TYPE_MAXIMUM(long);
}
return time_ns;
}
/* Returns time normalized timespec with .tv_nsec < TIMESPEC_HZ
and the whole seconds added to .tv_sec. If an overflow or
underflow occurs the values are clamped to its maximum or
minimum respectively. */
struct timespec
support_timespec_normalize (struct timespec time)
{
struct timespec norm;
if (INT_ADD_WRAPV (time.tv_sec, (time.tv_nsec / TIMESPEC_HZ), &norm.tv_sec))
{
norm.tv_sec = (time.tv_nsec < 0) ? TYPE_MINIMUM (time_t): TYPE_MAXIMUM (time_t);
norm.tv_nsec = (time.tv_nsec < 0) ? -1 * (TIMESPEC_HZ - 1) : TIMESPEC_HZ - 1;
return norm;
}
norm.tv_nsec = time.tv_nsec % TIMESPEC_HZ;
return norm;
}
/* Returns TRUE if the observed time is within the given percentage
bounds of the expected time, and FALSE otherwise.
For example the call
support_timespec_check_in_range(expected, observed, 0.5, 1.2);
will check if
0.5 of expected <= observed <= 1.2 of expected
In other words it will check if observed time is within 50% to
120% of the expected time. */
int
support_timespec_check_in_range (struct timespec expected, struct timespec observed,
double lower_bound, double upper_bound)
{
assert (upper_bound >= lower_bound);
long expected_norm, observed_norm;
expected_norm = support_timespec_ns (expected);
/* Don't divide by zero */
assert(expected_norm != 0);
observed_norm = support_timespec_ns (observed);
double ratio = (double)observed_norm / expected_norm;
return (lower_bound <= ratio && ratio <= upper_bound);
}