stress2: Added a regression test

tools/test/stress2/misc/fork2.sh

@@ -0,0 +1,135 @@
+#!/bin/sh
+
+#
+# SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+#
+# Copyright (c) 2022 Peter Holm
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+#
+
+# Regression test for D36069
+# thread_create(): call cpu_copy_thread() after td_pflags is zeroed
+
+# Seen before fix:
+# cc: error: unable to execute command: Segmentation fault (core dumped)
+# cc: error: linker command failed due to signal (use -v to see invocation)
+# Aug  9 18:27:47 freebsd-vm kernel: pid 32094 (ld.lld), jid 0, uid 0: exited on signal 11 (core dumped)
+
+. ../default.cfg
+[ `id -u` -ne 0 ] && echo "Must be root!" && exit 1
+
+dir=/tmp
+odir=`pwd`
+cd $dir
+sed '1,/^EOF/d' < $odir/$0 > $dir/fork2.c
+mycc -o fork2 -Wall -Wextra -O0 -g fork2.c || exit 1
+cd $odir
+
+set -e
+mount | grep "on $mntpoint " | grep -q /dev/md && umount -f $mntpoint
+[ -c /dev/md$mdstart ] &&  mdconfig -d -u $mdstart
+mdconfig -a -t swap -s 2g -u $mdstart
+bsdlabel -w md$mdstart auto
+newfs $newfs_flags md${mdstart}$part > /dev/null
+mount /dev/md${mdstart}$part $mntpoint
+set +e
+
+cd $mntpoint
+$dir/fork2
+s=$?
+pkill fork2
+[ -f fork2.core -a $s -eq 0 ] &&
+    { ls -l fork2.core; mv fork2.core $dir; s=1; }
+cd $odir
+
+for i in `jot 6`; do
+	mount | grep -q "on $mntpoint " || break
+	umount $mntpoint && break || sleep 10
+	[ $i -eq 6 ] &&
+	    { echo FATAL; fstat -mf $mntpoint; exit 1; }
+done
+mdconfig -d -u $mdstart
+cd $dir
+mycc -o $dir/fork2 -Wall -Wextra -O0 -g $dir/fork2.c; s=$?
+rm -rf $dir/fork2 $dir/fork2.c
+exit $s
+
+EOF
+#include <sys/param.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+
+#include <machine/atomic.h>
+
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <unistd.h>
+
+static volatile u_int *share;
+
+#define MX 5000
+#define RUNTIME (1 * 60)
+#define SYNC 0
+
+int
+main(void)
+{
+	pid_t pid;
+	size_t len;
+	time_t start;
+	int n;
+
+	len = PAGE_SIZE;
+	if ((share = mmap(NULL, len, PROT_READ | PROT_WRITE,
+	    MAP_ANON | MAP_SHARED, -1, 0)) == MAP_FAILED)
+		err(1, "mmap");
+
+	n = 0;
+	signal(SIGCHLD, SIG_IGN);
+	start = time(NULL);
+	while ((time(NULL) - start) < RUNTIME) {
+		while ((atomic_load_int(&share[SYNC])) > MX)
+			usleep(100);
+		n++;
+		pid = fork();
+		if (pid == -1)
+			err(1, "fork)");
+		if (pid == 0) {
+			atomic_add_int(&share[SYNC], 1);
+			while (atomic_load_int(&share[SYNC]) <= MX)
+				usleep(10000);
+			usleep(arc4random() % 1000);
+			atomic_add_int(&share[SYNC], -1);
+			raise(SIGHUP);
+			_exit(0);
+		}
+	}
+	atomic_add_int(&share[SYNC], MX * 2);
+	fprintf(stderr, "%d fork() calls\n", n);
+}