glibc/sysdeps/unix/sysv/linux/powerpc/test-gettimebasefreq.c

63 lines
1.8 KiB
C

/* Check __ppc_get_timebase_freq() for architecture changes
Copyright (C) 2012-2013 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
<http://www.gnu.org/licenses/>. */
/* Test if __ppc_get_timebase_freq() works and is different from zero. A read
failure might indicate a Linux Kernel change.
This test also use the frequency to compute the real elapsed time. */
#include <inttypes.h>
#include <stdio.h>
#include <sys/platform/ppc.h>
/* Maximum value of the Time Base Register: 2^60 - 1. */
#define MAX_TB 0xFFFFFFFFFFFFFFF
static int
do_test (void)
{
uint64_t t1, t2, f, diff;
t1 = __ppc_get_timebase ();
printf ("t1 = %"PRIu64"\n", t1);
f = __ppc_get_timebase_freq ();
printf ("Time Base frequency = %"PRIu64" Hz\n", f);
if (f == 0) {
printf ("Fail: The time base frequency can't be zero.");
return 1;
}
t2 = __ppc_get_timebase ();
printf ("t2 = %"PRIu64"\n", t2);
if (t2 > t1) {
diff = t2 - t1;
} else {
diff = (MAX_TB - t2) + t1;
}
printf ("Elapsed time = %1.2f usecs\n", (double) diff * 1000000 / f );
return 0;
}
#define TEST_FUNCTION do_test ()
#include "../test-skeleton.c"