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-rw-r--r--rt/tst-cpuclock1.c307
1 files changed, 307 insertions, 0 deletions
diff --git a/rt/tst-cpuclock1.c b/rt/tst-cpuclock1.c
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--- /dev/null
+++ b/rt/tst-cpuclock1.c
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+/* Test program for process CPU clocks.
+ Copyright (C) 2004 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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <errno.h>
+#include <signal.h>
+#include <sys/wait.h>
+
+/* This function is intended to rack up both user and system time. */
+static void
+chew_cpu (void)
+{
+ while (1)
+ {
+ static volatile char buf[4096];
+ for (int i = 0; i < 100; ++i)
+ for (size_t j = 0; j < sizeof buf; ++j)
+ buf[j] = 0xaa;
+ int nullfd = open ("/dev/null", O_WRONLY);
+ for (int i = 0; i < 100; ++i)
+ for (size_t j = 0; j < sizeof buf; ++j)
+ buf[j] = 0xbb;
+ write (nullfd, (char *) buf, sizeof buf);
+ close (nullfd);
+ if (getppid () == 1)
+ _exit (2);
+ }
+}
+
+static int
+do_test (void)
+{
+ int result = 0;
+ clockid_t cl;
+ int e;
+ pid_t dead_child, child;
+
+ /* Fork a child and let it die, to give us a PID known not be valid
+ (assuming PIDs don't wrap around during the test). */
+ {
+ dead_child = fork ();
+ if (dead_child == 0)
+ _exit (0);
+ if (dead_child < 0)
+ {
+ perror ("fork");
+ return 1;
+ }
+ int x;
+ if (wait (&x) != dead_child)
+ {
+ perror ("wait");
+ return 2;
+ }
+ }
+
+ /* POSIX says we should get ESRCH for this. */
+ e = clock_getcpuclockid (dead_child, &cl);
+ if (e != ENOSYS && e != ESRCH && e != EPERM)
+ {
+ printf ("clock_getcpuclockid on dead PID %d => %s\n",
+ dead_child, strerror (e));
+ result = 1;
+ }
+
+ /* Now give us a live child eating up CPU time. */
+ child = fork ();
+ if (child == 0)
+ {
+ chew_cpu ();
+ _exit (1);
+ }
+ if (child < 0)
+ {
+ perror ("fork");
+ return 1;
+ }
+
+ e = clock_getcpuclockid (child, &cl);
+ if (e == EPERM)
+ {
+ puts ("clock_getcpuclockid does not support other processes");
+ goto done;
+ }
+ if (e != 0)
+ {
+ printf ("clock_getcpuclockid on live PID %d => %s\n",
+ child, strerror (e));
+ result = 1;
+ goto done;
+ }
+
+ const clockid_t child_clock = cl;
+ struct timespec res;
+ if (clock_getres (child_clock, &res) < 0)
+ {
+ printf ("clock_getres on live PID %d clock %lx => %s\n",
+ child, (unsigned long int) child_clock, strerror (errno));
+ result = 1;
+ goto done;
+ }
+ printf ("live PID %d clock %lx resolution %lu.%.9lu\n",
+ child, (unsigned long int) child_clock, res.tv_sec, res.tv_nsec);
+
+ struct timespec before, after;
+ if (clock_gettime (child_clock, &before) < 0)
+ {
+ printf ("clock_gettime on live PID %d clock %lx => %s\n",
+ child, (unsigned long int) child_clock, strerror (errno));
+ result = 1;
+ goto done;
+ }
+ printf ("live PID %d before sleep => %lu.%.9lu\n",
+ child, before.tv_sec, before.tv_nsec);
+
+ struct timespec sleeptime = { .tv_nsec = 500000000 };
+ nanosleep (&sleeptime, NULL);
+
+ if (clock_gettime (child_clock, &after) < 0)
+ {
+ printf ("clock_gettime on live PID %d clock %lx => %s\n",
+ child, (unsigned long int) child_clock, strerror (errno));
+ result = 1;
+ goto done;
+ }
+ printf ("live PID %d after sleep => %lu.%.9lu\n",
+ child, after.tv_sec, after.tv_nsec);
+
+ struct timespec diff = { .tv_sec = after.tv_sec - before.tv_sec,
+ .tv_nsec = after.tv_nsec - before.tv_nsec };
+ if (diff.tv_nsec < 0)
+ {
+ --diff.tv_sec;
+ diff.tv_nsec += 1000000000;
+ }
+ if (diff.tv_sec != 0
+ || diff.tv_nsec > 600000000
+ || diff.tv_nsec < 100000000)
+ {
+ printf ("before - after %lu.%.9lu outside reasonable range\n",
+ diff.tv_sec, diff.tv_nsec);
+ result = 1;
+ }
+
+ sleeptime.tv_nsec = 100000000;
+ e = clock_nanosleep (child_clock, 0, &sleeptime, NULL);
+ if (e == EINVAL || e == ENOTSUP || e == ENOSYS)
+ {
+ printf ("clock_nanosleep not supported for other process clock: %s\n",
+ strerror (e));
+ }
+ else if (e != 0)
+ {
+ printf ("clock_nanosleep on other process clock: %s\n", strerror (e));
+ result = 1;
+ }
+ else
+ {
+ struct timespec afterns;
+ if (clock_gettime (child_clock, &afterns) < 0)
+ {
+ printf ("clock_gettime on live PID %d clock %lx => %s\n",
+ child, (unsigned long int) child_clock, strerror (errno));
+ result = 1;
+ }
+ else
+ {
+ struct timespec d = { .tv_sec = afterns.tv_sec - after.tv_sec,
+ .tv_nsec = afterns.tv_nsec - after.tv_nsec };
+ if (d.tv_nsec < 0)
+ {
+ --d.tv_sec;
+ d.tv_nsec += 1000000000;
+ }
+ if (d.tv_sec > 0
+ || d.tv_nsec < sleeptime.tv_nsec
+ || d.tv_nsec > sleeptime.tv_nsec * 2)
+ {
+ printf ("nanosleep time %lu.%.9lu outside reasonable range\n",
+ d.tv_sec, d.tv_nsec);
+ result = 1;
+ }
+ }
+ }
+
+ if (kill (child, SIGKILL) != 0)
+ {
+ perror ("kill");
+ result = 2;
+ goto done;
+ }
+
+ /* Wait long enough to let the child finish dying. */
+
+ sleeptime.tv_nsec = 200000000;
+ nanosleep (&sleeptime, NULL);
+
+ struct timespec dead;
+ if (clock_gettime (child_clock, &dead) < 0)
+ {
+ printf ("clock_gettime on dead PID %d clock %lx => %s\n",
+ child, (unsigned long int) child_clock, strerror (errno));
+ result = 1;
+ goto done;
+ }
+ printf ("dead PID %d => %lu.%.9lu\n",
+ child, dead.tv_sec, dead.tv_nsec);
+
+ diff.tv_sec = dead.tv_sec - after.tv_sec;
+ diff.tv_nsec = dead.tv_nsec - after.tv_nsec;
+ if (diff.tv_nsec < 0)
+ {
+ --diff.tv_sec;
+ diff.tv_nsec += 1000000000;
+ }
+ if (diff.tv_sec != 0 || diff.tv_nsec > 200000000)
+ {
+ printf ("dead - after %lu.%.9lu outside reasonable range\n",
+ diff.tv_sec, diff.tv_nsec);
+ result = 1;
+ }
+
+ /* Now reap the child and verify that its clock is no longer valid. */
+ {
+ int x;
+ if (waitpid (child, &x, 0) != child)
+ {
+ perror ("waitpid");
+ result = 1;
+ }
+ }
+
+ if (clock_gettime (child_clock, &dead) == 0)
+ {
+ printf ("clock_gettime on reaped PID %d clock %lx => %lu%.9lu\n",
+ child, (unsigned long int) child_clock,
+ dead.tv_sec, dead.tv_nsec);
+ result = 1;
+ }
+ else
+ {
+ if (errno != EINVAL)
+ result = 1;
+ printf ("clock_gettime on reaped PID %d clock %lx => %s\n",
+ child, (unsigned long int) child_clock, strerror (errno));
+ }
+
+ if (clock_getres (child_clock, &dead) == 0)
+ {
+ printf ("clock_getres on reaped PID %d clock %lx => %lu%.9lu\n",
+ child, (unsigned long int) child_clock,
+ dead.tv_sec, dead.tv_nsec);
+ result = 1;
+ }
+ else
+ {
+ if (errno != EINVAL)
+ result = 1;
+ printf ("clock_getres on reaped PID %d clock %lx => %s\n",
+ child, (unsigned long int) child_clock, strerror (errno));
+ }
+
+ return result;
+
+ done:
+ {
+ if (kill (child, SIGKILL) != 0 && errno != ESRCH)
+ {
+ perror ("kill");
+ return 2;
+ }
+ int x;
+ if (waitpid (child, &x, 0) != child && errno != ECHILD)
+ {
+ perror ("waitpid");
+ return 2;
+ }
+ }
+
+ return result;
+}
+
+
+#define TIMEOUT 5
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
generated by cgit v1.1 at 2024-11-07 04:07:51 +0000